View Full Version : Tuning advice required
New poster! (less than 10 posts)
Hi all
I have recently bought a great little phase 2 GTT. The car has been off the road having various jobs done to bring her back to mint. I bought the car with piper 285 cam, vernier pulley, ported and polished head, lightened and balanced flywheel and bottom end, low compression pistons, Grp A carb, Turbo Technics MD84 STG 4 Turbo, straight through exhaust and downpipe, twin grp a dump valves, water injection and an apexi boost control.
The garage I have commissioned to do mainly cosmetic work have taken the Grp A Carb off and used a std venturi de chocked new gasket set and altered the 1st and 2nd stage jet stating that the car made need a smaller jet. None of this means anything to me. This garage has also removed the apexi boost controller. I have now been given the car back on low boost and been told to go and find someone with a rolling road to tune it. I have no mechanical knowledge and need someone to finish the car's tuning off for me for a reasonable price.
Recommendations please for someone who can refit the Apexi for me, sort the carb situation out and rolling road the car? Local to Dorset, Surrey or Sittingbourne if possible.
All advice welcome
Cheers
Speak to scoff, long drive but he will get it right. Getting rid of the group A carb was a good idea. You can now get it set up running spot on, get an AFR gauge and you could fiddle your self.
I'm on Sheppey these days, or frequently up near the Surrey meet. If you want a cuppa
michael tierney
21-11-2015, 19:07
See
http://www.rtoc.org/contacts/?id=3
or even
http://www.rtoc.org/contacts/?id=1
turbo ted
21-11-2015, 22:27
No need for rolling road to setup carb just need AFR gauge and someone who knows what there doing bring it to mike at gt-turbo-spares.co.uk based in Southampton :)
New poster! (less than 10 posts)
Cheers for the comments gents.
I have an AFR gauge fitted.
The car previously had the option to switch from low boost to a 30psi when required. To get this back, surely I need to do a bit more than get the carb set up?
I'm making the assumption that the car was not running correctly when you took it in (i.e. it had been off the road for a while etc)? If so, who was the garage that did that work for you? They should be commended and recommended! They have probably saved you a lot of money.
A carb (without any additional fuel injection), can only be truly set-up to work properly at one boost level (through the adjustment of the various jets). With a boost controller that switches between 30psi for high boost and say 10psi for low boost, one of those boost settings will have resulted in the car running completely off.
If you are new to GTT's and carbs then honestly, starting from a good basis (as the garage have tried to do for you), is the best bet.
There are endless threads on here with information that can help you use your AFR gauge and alter the carb jets to get the car running well, then you can start out on a journey of tuning it and increasing the power to make the most of the mods on the car. In this instance I would start by disconnecting the water injection before tuning the carb as that's a real unknown currently.
Alternatively, take the car directly to Scoff. Your car has a lot of modifications that need someone with experience to really make the most of (cam timing, turbo map/capabilities, water injection activation etc).
Whatever you do, will you start a project thread on here with pics so we can track your progress and offer some support? :)
Matt Cole
22-11-2015, 12:08
30psi is crazy boost and difficult to fuel for. Also switchable boost setting is not ideal for a carb setup. I would set boost and fueling and leave it at that.
Matt Cole
22-11-2015, 12:12
New poster! (less than 10 posts)
Hi all
I have recently bought a great little phase 2 GTT. The car has been off the road having various jobs done to bring her back to mint. I bought the car with piper 285 cam, vernier pulley, ported and polished head, lightened and balanced flywheel and bottom end, low compression pistons, Grp A carb, Turbo Technics MD84 STG 4 Turbo, straight through exhaust and downpipe, twin grp a dump valves, water injection and an apexi boost control.
The garage I have commissioned to do mainly cosmetic work have taken the Grp A Carb off and used a std venturi de chocked new gasket set and altered the 1st and 2nd stage jet stating that the car made need a smaller jet. None of this means anything to me. This garage has also removed the apexi boost controller. I have now been given the car back on low boost and been told to go and find someone with a rolling road to tune it. I have no mechanical knowledge and need someone to finish the car's tuning off for me for a reasonable price.
Recommendations please for someone who can refit the Apexi for me, sort the carb situation out and rolling road the car? Local to Dorset, Surrey or Sittingbourne if possible.
All advice welcome
Cheers
Reading the above again this sounds like a good garage. They may have saved your engine!;)
francob80
22-11-2015, 15:56
30 psi = kaboom.
Take all the advice above and do away with the boost adjuster. Fuel for one boost level and do it right first time.
New poster! (less than 10 posts)
All comments gratefully received.
I'ill get a build thread up shortly:)
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