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Model specific boards => Golf mk4 => Topic started by: jonrandom on 11 January 2013, 20:13

Title: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 20:13
Ive got a Agu and im getting it sorted to run a big turbo, at the mo ive got the standard injectors on along with the standard sized diameter maf housing.

My question, can I put on the bigger injectors as long as I scale up the maf diameter as well? can the ecu take that into account and run ok? or should I wait until the tuners fit them?

Ideally id like to fit them both now but dont want to do damage and get bore wash or anything like that as the engine has now only done about 100 miles since rebuild and slowly breaking it in to get mapped.
Title: Re: Big turbo/fueling/mapping?
Post by: Chris. on 11 January 2013, 20:20
Chuck em in when you get mapped.

What turbo?
Title: Re: Big turbo/fueling/mapping?
Post by: Dave_IOW on 11 January 2013, 20:36
He has a TD05 16g from an evo.
Title: Re: Big turbo/fueling/mapping?
Post by: barrym381 on 11 January 2013, 20:37
Chuck em in when you get mapped.

What turbo?
sure its a td05 he has stuck on it  :evil:
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 20:38
Fair play, just wanted to get them in there and get it all sorted.

Turbo the TD05 big16G

Just want to get everything ready
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 20:39
Chuck em in when you get mapped.

What turbo?
sure its a td05 he has stuck on it  :evil:
He has a TD05 16g from an evo.

Yep :smiley:
Title: Re: Big turbo/fueling/mapping?
Post by: Dave_IOW on 11 January 2013, 20:40
I read somewhere that if you kept the proportions right with MAF housing and injectors, it was relatively safe to do, however going from 2.5 ID to 2.75 ID (vr6 housing) doesn't give you much scope for larger injectors anyway, until it's mapped of course.
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 20:48
I read somewhere that if you kept the proportions right with MAF housing and injectors, it was relatively safe to do, however going from 2.5 ID to 2.75 ID (vr6 housing) doesn't give you much scope for larger injectors anyway, until it's mapped of course.

I read that some where as well which is why I'm asking, ive got a 3.25 intake and either 440 bosch and adjustable fpr or siemens 630, to get the max out of the setup
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 20:52
But as dave said if you keep in the scale between them both is it ok?
Title: Re: Big turbo/fueling/mapping?
Post by: Dave_IOW on 11 January 2013, 20:56
I believe it is as they correct themselves out, aslong as you could get them pretty damn close, I think you'll be OK.

Disclaimer: I will take no responsibilty for any engine damage caused by this   :grin:
Title: Re: Big turbo/fueling/mapping?
Post by: topher on 11 January 2013, 21:00
it'll run, and be okay for running in if you're staying off boost. Last time i dyno'd a car with a similar maf/injector setup was only fuelling at about 0.95 lambda under boost. Its a bodge to keep the fuel trims in check but the ecu will have a hard time figuring out what is really going on with the engine load.
Title: Re: Big turbo/fueling/mapping?
Post by: Dave_IOW on 11 January 2013, 21:08
There you go mate, the proper answer  :afro:
Title: Re: Big turbo/fueling/mapping?
Post by: topher on 11 January 2013, 21:11
the proper answer would take several pages of text, i summarised :grin:
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 21:26
Nice one thats good to know, at the mo it won't boost properly at all, get to about 3.5k revs, starts to really boost then it starts to judder. Havent pushed it as breaking it in but pretty sure it is down to a leak in the intercooler pipe work mixed with no N75.

Instead of running the n75 I'm running a electronic boost controller but can the ecu take that in to account also? or as its not plugged in is it going to keep going into limp?
Title: Re: Big turbo/fueling/mapping?
Post by: topher on 11 January 2013, 21:39
the judder is probably fuel cut. on a setup like that you would really benefit from an AFR/lambda gauge.. i know they're not cheap but it could save you a lot of money in the long run. i'd plug the n75 in (not plumbed in to the pipework obviously), set the mbc to about 12 psi and see what happens
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 21:51
It the HKS EVC 6 boost controller so not a mbc, lots of settings of which I don't much yet but hoped it would help. Will plug the n75 back in, cheers

Is the AFR/lamba gauge to do with changing it to wide band? read some bits about that but didn't understand it properly.

Title: Re: Big turbo/fueling/mapping?
Post by: topher on 11 January 2013, 21:57
no need to do the me7/wideband upgrade, just a standalone wideband such as innovate. it'll mean adding another boss in to your downpipe for another o2 sensor. It won't be used for any kind of fuel control, its just so you can keep an eye on the air/fuel ratio
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 11 January 2013, 22:42
no need to do the me7/wideband upgrade, just a standalone wideband such as innovate. it'll mean adding another boss in to your downpipe for another o2 sensor. It won't be used for any kind of fuel control, its just so you can keep an eye on the air/fuel ratio

Cheers have pm'ed you about this, want to get the max out of my setup, is there anything else ive over looked?

Cheers
Title: Re: Big turbo/fueling/mapping?
Post by: Chris. on 12 January 2013, 00:03
I ran yellows and VR6 maf with no fuelling changes in map and overfuelled causing fuel to get into the oil.

Nixxy good!
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 12 January 2013, 00:53
Something like that is my worry which is why ive put the standard ones back on and standard maf for now, not that it will run with the maf plugged in at the mo anyways
Title: Re: Big turbo/fueling/mapping?
Post by: tshirt2k on 12 January 2013, 11:40
A other vote for a wideband gauge. I've found a wideband very useful to know what the fuelling is doing.
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 12 January 2013, 18:19
So is this what I want?

http://www.ebay.co.uk/itm/INNOVATE-MTX-AFR-Wideband-Air-Fuel-Ratio-Gauge-/160952913809?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item25798a8f91

cheers
Title: Re: Big turbo/fueling/mapping?
Post by: tshirt2k on 13 January 2013, 15:51
That would work. Not sure I'd trust the uego sensor was in good condition. May end up spending that again to get a new one.

Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 13 January 2013, 16:35
Ok cheers will look at getting a new one then. Ive been looking at them and there are so many out there with mixed reviews.

I cant afford to spend to much but willing to spend a few hundred. So is that MTX-L a good one to go for its seems to get good reviews for that price bracket? Read about the AEM ones being quite good?

Like this?
http://www.ebay.co.uk/itm/300733137728?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Is that worth it?

Any help and advice would be appreciated.
Title: Re: Big turbo/fueling/mapping?
Post by: marcos on 13 January 2013, 18:27
this is the one i have good piece of kit, i was recommended by another user to get it aswel

http://www.ebay.co.uk/itm/AEM-GAUGE-6-in-1-TYPE-WIDEBAND-UEGO-CONTROLLER-30-4100-/300454336182?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item45f47956b6
Title: Re: Big turbo/fueling/mapping?
Post by: tshirt2k on 13 January 2013, 19:17
Aem are good too. Stick to a known brand plx, innovate etc.

I like the idea of boost gauge in the middle.
Title: Re: Big turbo/fueling/mapping?
Post by: asboGTI on 13 January 2013, 19:18
*cough three way boost panel above headunit  cough*
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 13 January 2013, 20:38
this is the one i have good piece of kit, i was recommended by another user to get it aswel

http://www.ebay.co.uk/itm/AEM-GAUGE-6-in-1-TYPE-WIDEBAND-UEGO-CONTROLLER-30-4100-/300454336182?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item45f47956b6

Nice one that looks good, how have you found it, how often does it need recalibration?

*cough three way boost panel above headunit  cough*

Ive got the EBC up top with boost readings, so won't get another boost gauge

(http://i1138.photobucket.com/albums/n521/jonrandom/IMAG0331.jpg)

Just need to make up a surround.

Was thinking about putting the gauge instead of the ashtray but could get a few more and make a nice 3 gauge mounting!  :laugh:
Title: Re: Big turbo/fueling/mapping?
Post by: Prawny on 14 January 2013, 18:18
you'd be far better off running N75 control rather than a boost controller, a boost controller only controls peak boost, it has no idea what you're doing on part throttle, and as such, it'll make the car feel sh!te when trying to drive normally.

I wouldn't bother fitting the larger injectors and trying to bodge it to run, just leave the stock injectors and MAF in place for now and DO NOT let it boost at all, that judder you're hitting when it spools up is either fuel cut or a lean misfire, and it's very unsafe either way. Avoid.

Drive it off boost, don't floor it at all, take it to the mappers and have them fit the MAF and injectors when you arrive.

If you havn't got a wideband in the car, you're risking everything the instant you allow that turbo to spool up.

even 12psi on a td05 is going to be 260bhp+ easily, so well beyond the AGU injector capabilities.
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 14 January 2013, 20:59
Cheers for the info Prawny, I haven't got to 4k rpm if its judded always straight away back off and tried to keep off boost, glad I did that now!

This boost controller is wired in to the rpm and tps whether that makes a difference or not or do you think it would still be better just running the n75?

Wideband wise after a bit of reading think im going to get the innovate mtx-l one. From what ive read it seem more accurate than the aem one with the recalibrations, it got good reviews.

Well if I get rid of the EBC then I would have to get a few gauges and one for boost.  :smiley:
Title: Re: Big turbo/fueling/mapping?
Post by: Prawny on 15 January 2013, 10:56
hmmmmmmmmmm, if it's wired into TPS as well then it might not be so bad, I've not seen boost controllers wired up to TPS as well, but be pretty complex setting it up to deliver boost smoothly.

usually boost controllers are great at controlling peak boost, but do nothing for part throttle, so on a big turbo they're constantly trying to spool up to full boost as nothing is stopping it.

Having a TPS input could well fix this issue, although to be perfectly honest, if it's being mapped by someone competent then it's still not really needed, using the N75 gives the ECU full control over boost in all conditions, as well as the ability to cut boost if something goes wrong, which of course you can't do with the EbC.
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 15 January 2013, 16:50
Its a HKS EVC 6 and yes its seems seriously complex the manuel is about 1cm thick! I dont understand most of it yet and it take some time setting up with lots of fiddling and reading.

I got it really so that once its mapped I didnt have to run and max all the time. Will be taking to Rtech so think then im just going to plumb the N75 back in and leave it like that for mapping. One less thing to go wrong.

 
Title: Re: Big turbo/fueling/mapping?
Post by: Prawny on 15 January 2013, 17:41
What about wiring in an N75 switch?

I had exactly the same thoughts as you when I did my build, and I spent £200 on a gizzmo MS-IBC and wired that in.

I gave Niki the option of using that or the N75, and he tried the boost controller, but said that on the road it just didn't feel right on part throttle, strangely also, even when set to 0 duty cycle, the boost level still remained slightly above actuator pressure so you couldn't get power as low as you wanted.

On something like a td05 I'd guess you've got a fairly strong actuator, you may find that actuator pressure still makes pretty impressive figures and is nice and tame to drive for more normal use.

I wired a switch into my N75 and installed it on the dash here:

(http://i1218.photobucket.com/albums/dd408/prawn16/60d81ef2.jpg)

With the circuit broken the N75 valve remains open and the car runs on actuator pressure, which in my case is 15psi. With the switch on the N75 controls boost as normal and the car runs 21psi

Difference in power curves can be seen here:

(http://i1218.photobucket.com/albums/dd408/prawn16/IMG_7286.jpg)

It's insanely smooth on actuator pressure, yet still really quick.
Title: Re: Big turbo/fueling/mapping?
Post by: jonrandom on 15 January 2013, 18:50
Thats not a bad idea I like it, will defo do that if I can't get the EBC working. Yeah I've got a forge actuator with a spring kit for whatever one is needed in mapping, so guessing ill get pretty similar differences in maps like yours.

Well will try to get the EBC working and Nikki can always swap back to the N75 if it wont work.

Ordering the innovate tomorrow so hopefully that will help then lots of reading about EBC and tinkering.
Title: Re: Big turbo/fueling/mapping?
Post by: Wazzzer on 15 January 2013, 20:49
Nick which wire on the N75 valve did you connect the switch to? Just bought a "wife" switch for mine lol
Title: Re: Big turbo/fueling/mapping?
Post by: rio_gti on 15 January 2013, 22:33
Nick which wire on the N75 valve did you connect the switch to? Just bought a "wife" switch for mine lol

Haaaaaa
Title: Re: Big turbo/fueling/mapping?
Post by: Prawny on 15 January 2013, 23:01
Nick which wire on the N75 valve did you connect the switch to? Just bought a "wife" switch for mine lol

Either mate, it doesn't matter which, as you're just trying to break the circuit.

Well worth doing. On a ko3s it takes you back to about 150bhp
Title: Re: Big turbo/fueling/mapping?
Post by: asboGTI on 16 January 2013, 07:19
Nick which wire on the N75 valve did you connect the switch to? Just bought a "wife" switch for mine lol

Either mate, it doesn't matter which, as you're just trying to break the circuit.

Well worth doing. On a ko3s it takes you back to about 150bhp

Sorry to rob this quick but prawn you got a link to your build thread
Title: Re: Big turbo/fueling/mapping?
Post by: Prawny on 16 January 2013, 11:12
Orange link in my sig mate, also found here: http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/109831-prawn-bigals-a3-track-car.html

Might take you a while though! it's a bit long!
Title: Re: Big turbo/fueling/mapping?
Post by: asboGTI on 16 January 2013, 12:42
better than sittiing on lunch doing nothhing  :whistle: