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Model specific boards => Golf mk3 => Topic started by: GolfGTI8v on 09 September 2010, 16:23

Title: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 09 September 2010, 16:23
Hi All,

I'm new here, my name is Andy.  I've got a MK3 8v GTI which ive owned for a couple of years now.  I've maintained the car to a high standard and imo its a good clean MK3 with low miles so im looking to keep what Ive got and go for more power.   I've got my heart set on the 1.8T 20v conversion and from what ive seen/read online its been done before without too much hassle.  Im not looking for mega power etc.

Apologies if this has been asked several times before but im after some specific answers regarding the conversion. 

Can this been done for around £2000?

Are the engine mounts in the same location i.e. just use uprated mounts? i.e bolt straight up? Any welding/fab required?

Which gearbox/flywheel/clutch/linkage... Im guessing my standard 020 box wont take the power hike? Will it even bolt up?

With regards to wiring is it a nightmare? Could this be done by a competent mechanically minded diyer?

Do I have to run aftermarket management and if so what happens with regards to the Speedo etc can I retain mk3 clocks?


Any information at all would be greatly appreciated  :grin:

Many thanks 

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 09 September 2010, 16:28
Andy,

Not sure if you have, but read the first 2-3 pages of this thread...as we've been discussing it today:
http://www.golfgtiforum.co.uk/index.php?topic=166121.0
...before it went off topic. Sorry folks.

On top of all in that thread...you have the 'wrong' pedal box so you'll need to go to a hydraulic one to run a 16v/1.8T O2A/O2J gearbox as your O2O will go bang.
Can it be done for £2000...yes.
Can it be done properlyusing a good 1.8T, gearbox, pedal box, better brakes, better suspension...for £2000?
Not sure. Probably...if you do your homework.


Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 09 September 2010, 17:15
DOH  :embarassed: Sorry

yep just read through some great info!

ive just noticed this on qpeng http://www.qpeng.com/conversion_guide.html 

they used the mk2 gearbox?  020?  and suggesting a plug in and play wiring harness??  is this a good route to go?

Would it be possible/good idea to get a whole MK4 golf gti lump (with ancillaries) and box,  Fit the lump with my 020 box use their harness to sort the wring side and do the box change etc at a later date?   my box was recon'd about 2k mikes ago and id perfer to do the engine change as straight forward as possible and uprgrade box etc at a later date rater than in one hit if that makes sense ??  :huh:

Many Thanks

Andy



Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Dan_GTi8v on 09 September 2010, 18:08
I havn't read the linked thread, as tbh I cant be arsed :P but you dont need to use the 1.8t box, and you dont need to convert to a hydro clutch

what you need to do is get an 02a box from a 16v gti and use the seat ibiza clutch cable setup, (the reaon they use a mk2 box in the qpeng guide is because there putting it into a mk2!) this will allow you to keep a cable clucth and save messing about with pedal boxes. you cannot however use the 8v gti box as it is too weak and will break

In regards to the qpeng route, its been covered many many times, but general census seems to be qpeng is easier but more expensive and some people dont think its worth the risk of running the engine without a knock sensor (again info on this can be found using the search function, or for general info just google 'knock sensor')

The plug and play harness is handy to have and saves a bit of work but the engine management qpeng uses is far inferior to running oe management.

I'll be doing my conversion for around £2000, but im doing all the work myself and have also managed to get some good deals (AUM ecu plus remap for £300!)

First thing you really need to decide is which engine you want to run, as there are a fair few different 1.8t's that are compatable. Im using an AUM from a mk4 gti which runs a ko3s turbo, and is a fairly straight forward swap. I know others on the forums have used other engines though so it would be good to hunt around for info on all the variants and see which is right for what you want
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 06:05
I havn't read the linked thread, as tbh I cant be arsed :P but you dont need to use the 1.8t box, and you dont need to convert to a hydro clutch

what you need to do is get an 02a box from a 16v gti and use the seat ibiza clutch cable setup, (the reaon they use a mk2 box in the qpeng guide is because there putting it into a mk2!) this will allow you to keep a cable clucth and save messing about with pedal boxes. you cannot however use the 8v gti box as it is too weak and will break

O2A from a Mk3 16v, or an O2J from a Mk4 will do.
You say you don't need to use the 1.8T 'box which is correct...but if the engine has one bolted on, why bother looking for a Mk3 16v 'box? They are the same (bar minor gearing changes).

The lashed up cable conversion on a Cupra Sport is awful...the cable soon gets sticky and the clutch gets heavy. Add an uprated clutch to the box, which may well be required when the boost gets turned up. Going to a hydraulic clutch is a better solution, in my view.
Certainly not essential, but a better solution.

It's only a 30 minute job to change the pedal box from a 8v cable type to a 16v/VR6 hydraulic type, if the engine is out anyway.

Either way will work...
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 08:54
OMG, why is everyone putting a 20VT into there Mk3 now!

Sorry bud, just your the millionth person to post up about. Having a read through my thread and have a look on clubgti, look at the setup people run and see whats what.

Cable clutch conversion is fine, I have no problems so far. O2J has different mountings to the O2J, although yes the internals are the same.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: dom on 10 September 2010, 09:06
OMG, why is everyone putting a 20VT into there Mk3 now!

Sorry bud, just your the millionth person to post up about. Having a read through my thread and have a look on clubgti, look at the setup people run and see whats what.

Cable clutch conversion is fine, I have no problems so far. O2J has different mountings to the O2J, although yes the internals are the same.

Someone needs to compile all of the info that has been passed around over the last few days and then sticky it! Then if people still ask the same question, we can send them that way before we shoot them  :grin:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 09:21
I need to put something together really. They can ignore the QPeng stuff if they want go down another route but there would be lots of other useful info. Just can't be a$$ed :D
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 09:23
 :undecided: Sorry guys i didn't realise it was such a popular topic when i googled this i didn't get many results, however ive now acquainted myself with the search function some great info to be found!

Question though what's the best box to use with the 1.8 20v Turbo? and by that i mean i want to get away from crunching into second gear with fast changes i know its common on the MK 1, 2 & 3's but do the more modern boxes cure this? i was speaking to a friend who has a MK4 gti and still suffers the same crunch with fast changes up into 2nd,  i don't want to go to all that effort and still be crunching on fast changes.  I know there's allot of advise out there to change to thinner oil,  will this REALLY cure the crunch on any or more modern box?

If run the O2A from a Mk3 16v box, what's the limits this box will take?  as i understand its torque that kills boxes not hp?
is the hydraulic pedal box a straight swap or is there fab work involved?

Sorry for all the questions guys im continuing my research.   HOW many engine codes did VW use ffs  :rolleyes:

Thanks

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 09:31
OK I will put something together.

O2A diesel box, code CTN or ASD, all the other O2A boxes are too short. I have a 16v box. I get no crunching, just gotta make sure you keep the clutch in when you shift! Gearbox can handle it.

I would stick a cable clutch conversion on the O2A, but up to you. Its very easy to do.

20VT bolts in using Mk3 16v engine mounts.






Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 09:46
Thanks allot for all your help mate,  :cool:

Do the 1.8ts run the reverse clutch like the 8v? what's a good updated clutch u recommend? does the 1.8t retain its flywheel and clutch with the 16v box?

Cheers

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 10:08
Run the 16v/G60 flywheel and a sachs VR6 clutch. You will need a few bolts to convert to a single mass flywheel. I will put this info in the thread that I'm making.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 10:26
great thanks mate  :grin:


Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 10:31
I need to put something together really. They can ignore the QPeng stuff if they want go down another route but there would be lots of other useful info. Just can't be a$$ed :D

...as will many who want a hassle free install, and don't mind paying.
The more info, the more options there are to suit more budgets.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 10:39
OK I will put something together.

O2A diesel box, code CTN or ASD, all the other O2A boxes are too short. I have a 16v box. I get no crunching, just gotta make sure you keep the clutch in when you shift! Gearbox can handle it.

Differing view:
There is no way I'd run a diesel 'box...I'd want a 16v 'box at the very least, with the standard 3.67 FD...
If it were me, I'd fit a 3.94 to 16v ratios.
I can't see the point of having something high geared...but, that's down to the roads it'll be driven on.

Currently, I'm running 190+ BHP with a 4.2 FD on 16v ratios!

Different strokes for different folks...
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 10:47
I find the 16v box too short for me. Especially 1st, 2nd and 5th. The diesel box ratios look like they would suit me better
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: kells on 10 September 2010, 13:43
I find the 16v box too short for me. Especially 1st, 2nd and 5th. The diesel box ratios look like they would suit me better

Alot of folk i talk to about my conversion say go Derv box too mate...
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 14:31
Hi kells, 

Is the derv box option better that the box fitted to the AGU in the MK4? from reading on here the hydro clutch conversion doesnt look too hard and i guess it would be best to retain the MK4 box.  Does this bolt up ok with 16v mounts?


Have you competed your conversion?, if so how did you find the wiring?  I'm quite put off the qpeng stuff after reading about the lack of knock sensor.  Im keen to keep the original AGU management but totally lost in regards to the clocks, immobilizer, keys and the wiring/combining looms in general.

 :huh:

Thanks

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 14:39
Mk4 box won't bolt straight in I don't think, hence why using the Mk3 box makes sense as the internals are the same and you can still run hydro clutch if you want.

Knock sensors can suck my balls. The main reason OEM management is better is you can still plug it in to vag com. Bear in mind its not an easy task wiring it in!
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Dan_GTi8v on 10 September 2010, 14:49
as said by LL the reason ppl go for the 16v box is the mounts are already there, the mk4 box etc need a different bell housing.

regarding the 2nd gear crunching etc, this is a common problem with the 8v boxes as they are pretty weak, but the 16v boxes dont suffer from this

and regarding the oe management being hard to wire, meh i'll cross that bridge when I come to it :P how hard can it be its just a load of wires! :grin: there are a few quides that cover it if you search around, think its only 4 or 5 wires you need to splice together, most of the work is removing crap you dont need :)

Im done with this topic now, thinking about my engine just reminds me how poor i am :P
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:03

regarding the 2nd gear crunching etc, this is a common problem with the 8v boxes as they are pretty weak, but the 16v boxes dont suffer from this

Which 16v 'boxes?
O2A sure as hell do...2nd to 3rd synchros go. I've had mine re-built so solve that exact problem...
All VAG gearboxes are crap in that respect. My S3's O2M had the same synchro start to go.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 15:06
Cheers Guys,

Im likeing the sound of 5 wires :grin: anyone got anymore specific info??????,  I chuck my 8v ecu, use AGU engine loom and ecu and try and marry up AGU  loom to the 8v loom ?  ive got a mate who is quite handy with wiring and has wired alot of ford engine conversion but never VAG stuff im hoping he can help.  

Id like to keep VAG com if i can,  wont i lose the ABS etc with aftermarket? or is that seperate to the ecu?

ive got my eyes on an AGU lump hoping to pick up mid next week

 :smiley:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 15:10
@ Ess_Three

Is this a syncro problem? i had my 8v box recon'd 2k ago and from the word go it crunched with fast changes (Only up into 2nd)  when i challenged the company that rebuilt the box i was told im being to "aggressive" and there is nothing itself wrong with the box?  Must be VWs as no other cars ive ever owned have had crunching issues  :rolleyes:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:15
Cheers Guys,

I chuck my 8v ecu, use AGU engine loom and ecu and try and marry up AGU  loom to the 8v loom ?  ive got a mate who is quite handy with wiring and has wired alot of ford engine conversion but never VAG stuff im hoping he can help.  

Use the full AGU loom back to the fusebox...
Keep the Golf loom for heating, lights etc.


Quote
Id like to keep VAG com if i can,  wont i lose the ABS etc with aftermarket? or is that seperate to the ecu?

No, you keep the ABS...it's different wiring and a different controller.

Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:19
@ Ess_Three

Is this a syncro problem? i had my 8v box recon'd 2k ago and from the word go it crunched with fast changes (Only up into 2nd)  when i challenged the company that rebuilt the box i was told im being to "aggressive" and there is nothing itself wrong with the box?  Must be VWs as no other cars ive ever owned have had crunching issues  :rolleyes:


It's a soft-as-sh!te synchro material problem.
My old 8v O2O did it, 2nd to 3rd...
As did my pre-rebuild O2A 16v 'box...
As did my S3 O2M 'box.
Even my Fabia vRS was showing the signs as I sold it.
Funny that my old Nova, XR2, ITR & 911 didn't, all driven in the same manner by the same driver.

I think being 'aggressive' is the problem. Go forward, accross, forward...and it's fine. It'll last forever.
Go diagonally accross the gate and it'll end up crunching.
Diagonally may be fine on long ratio diesel gearboxes...but it's no use on a close ratio, short geared 'box.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: kells on 10 September 2010, 15:20
Hi kells, 

Is the derv box option better that the box fitted to the AGU in the MK4? from reading on here the hydro clutch conversion doesnt look too hard and i guess it would be best to retain the MK4 box.  Does this bolt up ok with 16v mounts?


Have you competed your conversion?, if so how did you find the wiring?  I'm quite put off the qpeng stuff after reading about the lack of knock sensor.  Im keen to keep the original AGU management but totally lost in regards to the clocks, immobilizer, keys and the wiring/combining looms in general.

 :huh:

Thanks

Andy

alright matey,

doing mine around dec/jan time, ill be using the OEM management, as thats just how i like to roll but i know LL has not had no issues with his qpeng set up, the knock sensor isnt a reason id not use it either.

as for the Gearbox, not sure which way im gonna go now, i really want to run the S3 6 speed box if im honest
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 15:26
S3 6 speed box Sounds good buddy!  is this the same fitment as the mk4 golf AGU box and thus requires mounts to be fabricated?

 :sad:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:28

as for the Gearbox, not sure which way im gonna go now, i really want to run the S3 6 speed box if im honest

Jeez...it's massive.
Heavy as hell, and huge.

If you want a 6 speed why not look for a Mk4 FWD 6 speed 'box?
O2S I think...easier to make fit than a O2M.

If you really want to go O2M, don't Dutchdub do a set of mounting bits?

The other option would be a 6 speed gear kit for your O2A?
Not cheap mind...but you can pick the ratios/FD.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:32
S3 6 speed box Sounds good buddy!  is this the same fitment as the mk4 golf AGU box and thus requires mounts to be fabricated?

 :sad:

Oh no...it's physically about twice the size and has completely different mounts.
O2A-O2J-O2S are all basically the same casing - and much as it's been said that an O2J won't fit...it will with minimal mods. There are holes that may need tapping / drilling out...but it'll go if you want it to.
Same, I believe, with O2S....although never had an O2S out of the car to comapre.

O2M (S3/TT) is a completely different design...and is so big you'll have to limit yiour steering lock or you'll risk hitting the O2M casing.
It'll fit the engine...but not so easily the engine bay.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 15:32
hi Ess_Three 

soft syncro metal ?  would a reputable gearbox company not replace all syncro as part of a rebuild,  i was told they threw the contents of my old 8v box in the bin when i took it in as it had 'destroyed itself'  ?? it cruched in to 2nd before and after the rebuild??  could it be they reused old syncros ?????  :angry:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 15:38
hi Ess_Three 

soft syncro metal ?  would a reputable gearbox company not replace all syncro as part of a rebuild,  i was told they threw the contents of my old 8v box in the bin when i took it in as it had 'destroyed itself'  ?? it cruched in to 2nd before and after the rebuild??  could it be they reused old syncros ?????  :angry:

Yeah, just the design...a soft alloy.
My new 'box (3rd evolution!) has modified synchros, which I think are a 3rd-4th or 4th-5th part modified to fit...they are made of a different metal and don't go Pete Tong so quickly...can't say for sure though, as I don't know...and it all seems a bit hush-hush!!
Special tweaks and all that, by the men who know. And I don't.

Let's just say, I'll not be breaking this gearbox any time soon...and the ratios are optimised for the engine!

Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 15:54
 :shocked: sounds like i should have used the man building your box

So the 8v and 16v Mk3 boxes are different?........ so much different in strength that the 16v Mk3 boxes can take 200+ bhp

and the MK2 8v box is again totally different from the MK3 8v box ?

taken from the qpeng site
"I notice the Mk2 AGU in your guide uses a standard 8v 'box, is that strong enough? 
Our original development Mk2 has now covered 30k miles with an ’AGU‘ engine on its original 150k mile 8v 020 ‘rod shift’ gearbox without any problems. However, the clutch had to be uprated and we have found the Sachs ‘sporting’ unit works well. While it greatly simplifies the conversion and keeps costs down, it has to be said the gearing is rather short for the power available. "

makes me wonder why so my differnce between MK2 8v and MK3 8v boxes?
 
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 16:01

So the 8v and 16v Mk3 boxes are different?........ so much different in strength that the 16v Mk3 boxes can take 200+ bhp

Hell yeah...Mk 3 8v uses the rod change (better feel), cable clutch, smaller casing (weaker) O2O gearbox like the Mk2 did.
Mk3 16v uses the cable change, hydraulic clutch (easier to operate), bigger casing (stronger) O2A - bigger (heavier) flywheel too.

Power doesn't kill gearboxes...don't forget that...not at around the 200 BHP mark anyway...it's torque that does.
I've been putting just under 200 BHP through my 16v O2A 'box for years...but it's relatively low on torque, and the torque curve is gentle.
It may not take 350 lb-ft and 300 BHP quite so readily.

Quote
and the MK2 8v box is again totally different from the MK3 8v box ?

The same basic 'box as far as I know...both O2Os.


Quote
makes me wonder why so my differnce between MK2 8v and MK3 8v boxes?
 

Gearing?
Drive flange diameter?
Don't know to be honest...
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 16:21
so running the AGU on the 8v box will last no time at all but the 16v box should in theory be up the the task? at the torque a 200+ bhp AGU lump will make

the reason i ask the difference between MK2 8v and MK3 8v boxes as someone mentioned earlier on this thread the MK3 8v will go bang in no time yet the qpeng guys got 30k outta the mk2 8v box

id like to fit the best box i can with the least hassle tapping holes for the MK4 box or making mounts id rather not.  I want to start hunting for a box but need to know 100% which box to go for  :embarassed:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Len on 10 September 2010, 16:24
Thought the flywheel had to be lightened?
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 16:25
flywheel had to be lightened ?? how come ?
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 16:32
Thought the flywheel had to be lightened?

Which flywheel?
The silly dual-mass 1.8T thing?
Best thing to do with that is unbolt it and bin it...didn't LL say a G60 flywheel fits?

A lightened flywheel will help I guess...but on a turbo engine, off boost...I'd have thought a low inertia engine will little flywheel effect could bog down more easily?

Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 10 September 2010, 16:42
so running the AGU on the 8v box will last no time at all but the 16v box should in theory be up the the task? at the torque a 200+ bhp AGU lump will make

the reason i ask the difference between MK2 8v and MK3 8v boxes as someone mentioned earlier on this thread the MK3 8v will go bang in no time yet the qpeng guys got 30k outta the mk2 8v box

id like to fit the best box i can with the least hassle tapping holes for the MK4 box or making mounts id rather not.  I want to start hunting for a box but need to know 100% which box to go for  :embarassed:


I'd not even consider an O2O...I'm not exactly kind to gearboxes and wouldn't want to nanny it.
If you are a smooth driver who looks after things, then an O2O may last a lifetime. I'm not. I'd want the strongest sensibly available 'box in there...so a O2A/J.

Put it this way...iv VW thought it required to engineer a new gearbox for cars with over 150BHP (G60, ABF, VR6) I'm guessing it wasn't because they felt like it.
If they thought it required...it's probably because the older, smaller O2O can't handle the sustained abuse.

It's your car...you go with what you want...
Personally, I'd want an O2A with my choice of ratios in, and at the very least a set of the uprated diff bolts in place of the stupid rivets...and whilst the crownwheel is off, it'd be churlish not to fit an LSD...
And new bearings...
And new synchros...
Probably change the FD...
Fit uprated selector pins and bushes...
A billet lower tower support bearing...
Oh, and an uprated upper tower support bearing too.
Maybe fit an uprated set of 5 gears too.
Or 6.

Then you end up with a bullet-proof O2A... how far do you want to go / want to spend?  :wink:


O2A is an easy sawp....the driveshafts fit, but the gearchange is crap.
O2J is a harder physical fit, the drive flanges need swapping from 108mm to 100mm, but the gear selector tower is FAR better - especially if you fit a Mk4 Golf lefer mech...and the OEM VAG short shift from a TT.

Pros vs cons...
Do your homework. There is an easy way...a harder way...and a far harder way again that gives big rewards and the ultimate bombproof ways.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 10 September 2010, 17:02
GREAT info there thanks mate  :smiley:

The more i read into this conversion the more i lean towards the 'do it once do it right' after all if im spending the money and going to the effort i might as well go the extra mile.   I don't really have a budget so to speak as i will spend month to month,  i'll get an engine and box this month and look to upgrade the box and collect other required parts come next pay day
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 10 September 2010, 19:44
Use an 02A box and the Mk4/A3 shift tower (yes it fits, just make sure you get the right one, 5 speed!). So you get a much better feel. DMonday on here with his VR has fitted an A3 one and he says its miles better. I have one lying around, just need to find time to fit it; need to take my downpipe off and the four bolts holding it on are the most awkward bolts to get too, so really I just CBA :D

Yes a G60 flywheel works, its the same as the 16v flywheel and run a Sach's VR6 clutch with it :)

No need to lighten the flywheel, I wouldn't do it either, the weight you lose by converting to single mass is plenty.

Totally agree with the "Do it right first time", I kinda of did, but got it on the road and didn't finish it properly, hence why the engine bay looks a little ratty. I didn't cut corners on the conversion though!
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Dan_GTi8v on 10 September 2010, 19:48
agu engine with a 16v gti 02a gearbox, abf flywheel, and a vr6 clutch. sorted :)
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: jonnypolish on 10 September 2010, 20:27
I assume the same setup can  applied to the BAM/AMK?
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Dan_GTi8v on 10 September 2010, 21:29
yeah afaik all the transverse fitted (as opposed to Longitudinal) are the same fitting wise, only differences are the port sizes and the turbos, and drive by wire or not

I meant aum above btw not agu :P though it still applys to agu, im just not using it :) I think LL used an agu.
 
Difference between those 2 are agu has bigger ports is not dbw and has a k03 turbo, whereas the aum has the smaller ports but is dbw and has the k03s turbo. Both have the same bhp (150) but them aum can get a bit more out if there both mapped.
I believe the k03s turbo can be fitted to the agu though which would make it more powerfull than the aum, but thats a bit of fannying about for not much gain :P
I think the amk and bam engines are also the same as the aum but just run the bigger k04 turbo (may be wrong about this)
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 11 September 2010, 05:59
Use an 02A box and the Mk4/A3 shift tower (yes it fits, just make sure you get the right one, 5 speed!). So you get a much better feel. DMonday on here with his VR has fitted an A3 one and he says its miles better. I have one lying around, just need to find time to fit it; need to take my downpipe off and the four bolts holding it on are the most awkward bolts to get too, so really I just CBA :D


The shift tower that bolts into the gearbox is pretty much the same, O2A to O2J...the linkage attachment points, leverage ratios and adjustments differ and can only match the correct O2A/O2J shift cables and lever assemblies.

Fitting a O2J gearbox shift tower to an O2A does nothing...especially as you can't get the cables working correctly...however, fitting the complete Mk4 gear lever assembly, shift cables and gearbox shift tower will improve feel and shorten the throw.

It's something I've been working on of late so have all the bits stripped to compare...
O2A cables can be improved, as can the O2A lever mech (throw shortened, as mine has been) so gains become less and less...but just to make people aware...it's not just the gearbox shift tower bit you need...it's the lot. You will need:

The shift tower assembly complete with cable attachment points (bolts straight into the O2A casing)
The 02J shift cables
The O2J gear lever assembly (does not bolt straight into the Mk3 'shell...but guides are on the interweb on how to do it).

Would I do the conversion?
Probably, if you have the whole front end stripped to swap the engine and you can access the shift cables easily.
I can see LLs point...doing the swap with the engine in, is a nightmare!
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: LazyLunatic on 11 September 2010, 15:18
Yer that's what I meant, all the cables and shifter too.

I have an AUM Dan. I just swapped the TB for a Mk3 GTi 8v one.

Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 11 September 2010, 15:37
Yer that's what I meant, all the cables and shifter too.

Just making sure the OP knew it's not just the gearbox bit that needs changing.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Wayne on 11 September 2010, 20:46
1) http://www.golfgtiforum.co.uk/index.php?topic=124485.0 :afro:

2) think long and hard before running qpeng it would not be my choice.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 13 September 2010, 10:56
Excellent, thanks again for all the info :smiley:

Im going to use the 02a gearbox but to confirm can i retain my 8v driveshaft's with this box? also i will need to convert to cable change? or can i modify it to run my 8v linkage ?

I want to get the 02a rebuilt and rivets replaced with bolts but what else can i get done to improve it whilst its apart?..... without spending thousands that is ?


Thanks

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 13 September 2010, 11:37

Im going to use the 02a gearbox but to confirm can i retain my 8v driveshaft's with this box?

I believe so...as far as I recall, all 5 stud Mk3s had the same hubs/driveshafts...so you'll be fine.


Quote
also i will need to convert to cable change? or can i modify it to run my 8v linkage ?

You'll need to convert to cable change.
You can go with a clutch cable...but if you have the front end stripped down, engine out etc...it's no big deal to do cable change lever assembly and hydraulic pedal box, if you choose to.


Quote
I want to get the 02a rebuilt and rivets replaced with bolts but what else can i get done to improve it whilst its apart?..... without spending thousands that is ?

New synchros 2nd/3rd? If you are having it rebuilt then bearings, seals and synchros should be included.
LSD? You'll struggle for traction with turbo torque...a decent Diff will help out.
Change the FD if you want the gearing lower/higher?

The budget becomes the limit...

Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Dan_GTi8v on 13 September 2010, 12:27
Im going to use the 02a gearbox but to confirm can i retain my 8v driveshaft's with this box? also i will need to convert to cable change? or can i modify it to run my 8v linkage ?

just a quick search but I found a few of posts with info about fitting a cable clutch to the 02a box.

http://clubgti.co.uk/forum/showthread.php?p=962070
http://www.clubgti.com/forum/showthread.php?t=48287&highlight=clutch
http://forums.vwvortex.com/showthread.php?1060826
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 13 September 2010, 12:34

just a quick search but I found a few of posts with info about fitting a cable clutch to the 02a box.


I assumed the 'cable change' bit was referring to the gear selectors?
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 13 September 2010, 15:20
Yes i was referring to the cable change, i know i will have to convert to a hydro clutch but was wondering if u can change the 02a to a rod linkage?

ive not driven a cable gear selector is the feel really allot worse?  I also read u can use a VR6 box if change the bell housing and its a big improvement? any truth in that?   :undecided:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 13 September 2010, 15:36
Yes i was referring to the cable change, i know i will have to convert to a hydro clutch but was wondering if u can change the 02a to a rod linkage?

No, not that I know of.
The only conversion I know of goes the other way...to allow cables to be used with a CAE Motorsports shifter, on an O2O gearbox.
Nothing to run rod change on an O2A.


Quote
ive not driven a cable gear selector is the feel really allot worse? 

I don't find so.
It's a long throw...something rectified fairly easy by making/buying a quickshifter.
I don't have any issues getting gears, or suffer from lack of feel.


Quote
I also read u can use a VR6 box if change the bell housing and its a big improvement? any truth in that?   :undecided:

No, none.
VR6 is just an O2A...
Doesn't matter which O2A it is, they all feel the same...they all use cables to change, most have the same ratios inside (16v / VR6) just different FD ratios to suit.
No sense whatsoever finding a VR6 'box and swapping the bellhousing...unless you really want the longer gearing of the VR6. The feel of the gearchange won't be affected in any way.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 13 September 2010, 15:58
Cheers Ess_Three!  my knowledge of gearboxes is rather limited :embarassed:
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 13 September 2010, 16:02
Cheers Ess_Three!  my knowledge of gearboxes is rather limited :embarassed:

My pleasure...
I'd rather you ask and satisfy yourself what's what, than buy crap and be stuck with something that doesn't work.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 13 September 2010, 16:28
Thanks!

Are you able to recommend anyone whose good with these boxes?

Ive heard good things about http://www.gearboxman.co.uk/  but only from the ford scene?
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 13 September 2010, 17:01
Thanks!

Are you able to recommend anyone whose good with these boxes?

Ive heard good things about http://www.gearboxman.co.uk/  but only from the ford scene?


I'm sure they will be fine. A gearbox is a gearbox...nothing special in a VW 5 speed unit.
I'm lucky to have a mate who does mine.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 16 September 2010, 09:50
Update!  Soooooooooo yesterday i aquired an AGU engine and box which came with a free car  :grin:  Runs and drives great but @ 120k miles i think i will get the engine refreshed i.e rings, valve seals and bearings etc to be on the safe side as im want to run 230hp ish.  Got a great deal on it so im v happy :tongue:

(http://i805.photobucket.com/albums/yy339/AndyGolfGTI8v/photo9.jpg)
(http://i805.photobucket.com/albums/yy339/AndyGolfGTI8v/photo3.jpg)

Questions though.. these engines suffer from failure of the plastic impellers on the water pump do they not?

Also can anyone recommend a good head gasket or is the OEM good enough?

Can i send my A3 ecu off to anyone to get the immobilizer removed?

Thanks

Andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Rare OEM on 16 September 2010, 09:56
Yes i was referring to the cable change, i know i will have to convert to a hydro clutch but was wondering if u can change the 02a to a rod linkage?

No, not that I know of.
The only conversion I know of goes the other way...to allow cables to be used with a CAE Motorsports shifter, on an O2O gearbox.
Nothing to run rod change on an O2A.


Quote
ive not driven a cable gear selector is the feel really allot worse? 

I don't find so.
It's a long throw...something rectified fairly easy by making/buying a quickshifter.
I don't have any issues getting gears, or suffer from lack of feel.


Quote
I also read u can use a VR6 box if change the bell housing and its a big improvement? any truth in that?   :undecided:

No, none.
VR6 is just an O2A...
Doesn't matter which O2A it is, they all feel the same...they all use cables to change, most have the same ratios inside (16v / VR6) just different FD ratios to suit.
No sense whatsoever finding a VR6 'box and swapping the bellhousing...unless you really want the longer gearing of the VR6. The feel of the gearchange won't be affected in any way.

+1
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: Ess_Three on 16 September 2010, 10:39
Questions though.. these engines suffer from failure of the plastic impellers on the water pump do they not?

Yes. Just fit a new water pump...I believe the part was revised during it's life anyway.


Quote
Also can anyone recommend a good head gasket or is the OEM good enough?

OEM is fine.


Quote
Can i send my A3 ecu off to anyone to get the immobilizer removed?

I think Custom Code or REVO will be able to remove the immobiliser whilst re-mapping.
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: GolfGTI8v on 16 September 2010, 11:49
im going to wire it up with the help of a friend on the driveway and get it up and running on standard map.  Will get it remapped once ive done a few miles in it. So i need to get the immobiliser removed else it wont run??? as im hoping to keep original mk3 clocks and keys etc.

Ive emailed a couple of places asking if they can simply remove the immobiliser from the ecu for the time being  :huh:

thanks

andy
Title: Re: New Member looking to convert MK3 8v to 1.8 20v Turbo
Post by: popleyruss on 29 January 2012, 15:32
How is this build going ????