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Discussion Starter · #1 · (Edited)
I have an R32GTR. Standard turbos & stock internals. Good strong engine with NO breathing thru' the oil filler cap, no smoke, no misfires etc...
It has had a stage one upgrade (Apexi induction with standard AFMs, Mines ECU, Trust Downpipes, 4" titanium exhaust & decat pipe).
But it is definately down on power.

The story so far:
Very shortly after I got the car, I took it to a well known tuners for a check up. We discovered that the Crank Angle Sensor was set quite retarded, and in fact was u/s. We fitted a new one and set it at 20 degrees before TDC.
Everything then was great, good pick-up in all gears - no problems whatsoever.
I then changed the engine covers for polished ones, and of course had to remove & replace the CAS. I did my best to get the position right, but the car was somewhat down on pulling power. It was very noticable, especially in second, which always gave me a mighty shove in the back before. I assumed I had not correctly replaced the CAS.
I found a local Scooby specialist who had a timing light, and when we checked the CAS, the position was still 20 degrees before TDC. So we put it on his dyno.
This revealed that I was only getting 312 bhp at the flywheel.
We moved the CAS 4 degrees (advance) and gave it a run, but it started to det, so we put it back. He could do no more as he didn't have the kit for it.
It also revealed that although my Greddy Boost Controller said my maximum setting was at 1 bar, and my Defi gauge said exactly the same (both reputable makes), I was only actually getting 0.9 bar of boost.
So, the question is really; where do I go from here ??
1) Do I book it in for a full engine remap as there may be other issues that I am not aware of ?
2) Can I turn up the boost to give me the 1 bar that I thought I already had ? Is it safe to do that ? What extra BHP will another 10% of boost give me ?
3) Take it back to the tuners, with a possible open cheque book, and say, please sort it out for me ?
4) Another course of action that I haven't even thought about ?
I understand that there is a cost, and I accept that, but I don't really want to be going down any more dead ends. The dyno cost £88 (not a fortune, I know), but that just ended up giving more questions and no real answers to the problem. You could go on like that for ever........

ANY thoughts, opinions, advice, or answers to the above would be greatly appreciated.
Many thanks for your time.
 

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My guess is that you've got a split in a boost pipe somewhere and it's leaking air under boost. Under vac the split may be sealed by the vacuum contracting the pipe so you get no missing or irregular idling but under boost is leaking. That would give you the loss in power you're experiencing.

Just my 2p.
 

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taking it to a tuner could actually save money in the long run, due to the fact that they know what they are doing/looking for which will resolve the issue quicker and more precise.Spending less money on un-needed items.
just my 2p
 

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Totally agree with Car Killer. Take it to a tuner AFTER checking as many parts as YOU can. This will potentially reduce the costs.
As I've said before I'd rather spend 1.5 hours @ £80/hour at a Skyline specialist than 4 hours at £50/hour

TT
 

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Dont mess about with it. Give it the once over if you cant spot anything get it looked at by A skyline expert. Its not worth the risk of leaving it and causing a rebuild. Hopefully its a lose/ damaged pipe as stated above.
 

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Discussion Starter · #7 ·
Took it to RB Motorsports & it's all sorted.
Fine tuning on the CAS was required - but not something to be attempted without the right experience methinks.
Thanks to Rod & Steve, and all the above for the advice.
 
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