supercharging an 8v gti

[Khare]

Was talking to DH last night and the cable change gearbox is my the best upgrade, from the 16v seats.
He also said I should invest in wideband lambda as it would offer better tuning options, and use the crossflow head, which he has and will be for sale at some point in the future 
He said it's gonna cost more than a grand though...He said a grand is what I'll spend on the wiring alone, and then another grand will go towards the engine preparation and fabricating. I'm gonna buy an used 8v gti engine, strip it, clean it, rebuild it with ARP bolts and new seals and gaskets all over and then stick the cable change gearbox on it, that way the engine is ready to be put on the car as a whole rather than in bits. All that's left is fabricate brackets for charger and plug it into the MS loom. That MS loom will make engine transplants plug and play pretty much, so after the 8v charged unit I can stick a 1.8T or a 16vT in easy.
I think that is the best option, as I will have a strong engine and wiring that won't catch fire as he said  Will be pricey though, but it will be done at some point 

[Wayne]

So all in all you could up knocking a hole in nearly £3k is it worth it.

[Khare]

So all in all you could up knocking a hole in nearly £3k is it worth it.

hmmm.....that is the big question, is it worth it? As I say I was looking to spend about 1 grand, basically bolting on a charger and running low boost, a starter project and a base. With time upgrade the bottom end for a forged counterpart and the head to a fully loaded spec.
As DH said though, do I want an engine that will blow after 1000 miles or wiring that will catch fire? I have to seriously think about what I do, find out how much psi I need to run to keep the stock internals and see what my options are.

[VeeDubGTI16v]

your looking at 2 corrado g60's for the money now 

[Horney]

your looking at 2 corrado g60's for the money now 

Indeed for £3K you could get a G60 lump, the loom, the ECU, get it chipped and pullied for that!

nick

[axewielder]

you could do the MS at greatly reduced prices if you DIY it but you have to be a bit competant with electronics, all the info is open source so you can get all the circuit diagrams+ just buy the componants separately.

[Wayne]

£1500 http://cgi.ebay.co.uk/AUDI-A3-VW-GOLF-1-8T-20V-ENGINE-CONVERSION-AGU-CODE-70K_W0QQitemZ260498146715QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item3ca6e6459b

[bored_Welsh_lad]

As you all know i have been in the process of building up the charged 8v lump for the last 2yrs through time. .

I would like to highlight a few points here.

1.Lets start with the M45/M62 charger... The M45 charger is good up to 10psi but then the compressor map becomes unstable due to the charge temps, i know of people who are running 45's with 16psi and aquamist to lower charge temps. The m62 obviously is a bigger compressor unit and thus will be able to provide more power..

2.X-Flow heads. If you are going to run the x-flow head then you might run into issues with the space at the front of the bay. The standard head polished and ported with a decent cam will provide plenty of flow for what you require. I have spoken to a few people on this point and they say that the standard head has quite poor flow but with a bit of work is suitable for FI applications.

3.Management. If you are going to be mapping this yourself then i would suggest you get megasquirt simply because of the amount of people who have worked on it. The standard management even with a MAP sensor provides issues with mapping as Badger5 found when he mapped an charged 8v on ClubGTI.

4. Compression. I spoke to the person who provided my brackets about this issue and found that you can run quite easily on standard compression at 5psi (standard charger pulley on m45) as long as its mapped correctly. As soon as you start looking to go over this and run smaller pulleys then stacked gaskets are the way forward. To the point of spacers and arp bolts etc.. I honestly wouldn't bother. Toyotec on CGTi has a 16vt running stacked gaskets on the original bolts and has had no issues with them at all..

5. Brackets. Do you have a/c. I do on mine and the bracket is the simpliest thing in the world to have made up. I dropped mine off to a mate and he made them for me and it runs true with no issues for mounting...I can bolt my charger on in about 5 mins.

6.Fuelling. Standard fuel pump is fine, injectors will need uprating. I have gone for g60 injectors and had them bench tested. Theres people out there running 440's but that as discussed on CGTi is overkill.

7. Wideband. Is a must in my mind just so you can keep an eye on what the car is doing incase you have any issues with fuelling... Can be picked up quite cheaply..

8. Cooling. At 5psi you wont need much cooling, as soon as you start to get over this you might come across a few issues. I have a small charge cooler at the moment as it limits the pipework i require.

9. Setup.. As per the diagram below, i suggest you relocate the tb to in front of the charger and run a recirc. This will allow you the best throttle in terms of drivability and not snappy as some people have confirmed when ran in the typical setup.



10. Headache... Enjoy it..

[axewielder]

What type of recirculating valve do you suggest using+ for cams look @ welsh's thread, minimal overlap is required

[bored_Welsh_lad]

I have managed to get hold of the inlet pipe for the charger as its an oval shape, this contains the recirc valve that recircs from between the charger and tb back to the outlet of the charger..

I honestly couldnt quote the best recirc to use, maybe get hold of a forge that you can change the spring in and work through the various spring grades to suit your application.