Dyno Chart Full Of Fail - Please Help

[djr81]

Just fixed a boost control issue and then had my car run up on a dyno. See attached. Brilliant if it was an RB20 but it is a 26. Cant even begin to explain how frustrated I am. Where should I go looking first?

Current plan is to set it on fire.

[r32-25t]

What is fitted to it?

[Roy]

Collapsed mufflers, cat....plug gaps and of course the quality of the tune itself

[djr81]

Well it doesn't matter so much as why the hell is it only putting out 400hp on 20lb.

But:

80mm afm's.
-5 turbros.

PWR intercooler.

256 degree inlet cam, 252 exhaust

Cleaned up head.

forged internals with new crank, carillo rods.

stock exhaust manifolds, ported.

Tomei dumps and whatever you call the pipes after that.

3.5" exhaust.

Generally stuff and done properly.

Edited July 31, 2015 by djr81

[r32-25t]

I take it that its been tuned and etc

Japanese branded against? If so did you remove the restrictor?

Good quality cat or even better gone?

The other thing that seems to be coming up a lot is crank angle sensors on the blink

[GTRPSI]

Run out of injectors and pump?

Or a really conservative tune.....

[djr81]

Prior to the rebuild at one point it ran 450rwhp on 15lb with the same exhaust but different cams (Poncam B's which suck)

Was expecting something like 480rwhp. AFR's are 11 and a bit. Doesn't drive like its lacking ignition advance.

Cas was replaced 12 months ago.

Injector duty is well below 100%

Edited July 31, 2015 by djr81

[mr skidz]

HP should say KW

[r32-25t]

Did you cut the valve seats? And what valve springs did you use? Did you check the seat pressure?

[Dose Pipe Sutututu]

what's the timing like? does it ramp up after max torque is reached or is it flat all the way through the RPM range?

[djr81]

Well row 18 on the PFC reads 12 12 12 12 12. 12 13 14 15 16. 16 16 16 16 16. 16 16 16 16 16.

Give or take its add 2 degrees for each cell in row 17 and add 2 for each row after 18.

So pretty well flat.

Edited July 31, 2015 by djr81

[djr81]

Did you cut the valve seats? And what valve springs did you use? Did you check the seat pressure?

I know where you are going with that and the answers are tomei and dunno. So does the output show float?

[r32-25t]

The way it flattens out and goes wavy is a sign that maybe the case

[KiwiRS4T]

Did you ask the tuner if he found any problems? You don't mention adjustable cam gears. RB26s respond well to adjustment of cams.

And don't be shy - who was the tuner and how long did the tune take?

What fuel pump do you have and how old is it?

[Roy]

Same exhaust.... Still. If it's 10 years old and had been bumped on-off the car I would want to be sure that a baffle hasn't corroded and come loose etc. Easy enough to drop it snd check. Ditto rag in cooler pipe.

I wouldn't jump to the conclusion that head and springs are a problem until you have done basic checks.

Tuner can't guide you based on how engine responded to fuel and ignition numbers?

[djr81]

Same exhaust.... Still. If it's 10 years old and had been bumped on-off the car I would want to be sure that a baffle hasn't corroded and come loose etc. Easy enough to drop it snd check. Ditto rag in cooler pipe.

I wouldn't jump to the conclusion that head and springs are a problem until you have done basic checks.

Tuner can't guide you based on how engine responded to fuel and ignition numbers?

Yeah I think I will have to start with the exhaust and cat and then pull the timing belt cover off it to see where the cams are at.

I only asked the local bloke to stick it on the dyno and see that it was ok rather than to tune it. He didnt do the tune that is in the car, that was done in Perth and I am starting to suspect it is less than complete. He pulled a bit of fuel out and said it gained eight or so horsepower. Didnt ask about ignition as the fail was doing my head in. But 70-80hp is alot to explain away by tune or strapping it down fairly hard (his other throwaway comment) or any other thing.

It makes good torque or atleast as good as it ever has just after the knee point in the curve when the boost flattens out it doesnt keep making power.

The previous number was 408 hp on a hub dyno with 16lb.

It has a Nismo fuel pump and the afrs are in the11's.

[Dose Pipe Sutututu]

my point of view get another opinion on the tune. I personally wouldn't have a timing map like that, but that's my personal choice.

[KiwiRS4T]

So you have a fully forged engine but won't pay $1000 for a proper tune!

If it had a decent tune last time it my not take that much to bring it up to speed but 70 - 80 hp difference in tune is entirely possible - even more. And if you haven't got adjustable cam gears put a set on first so that your cams can be adjusted.

[djr81]

I never said that at all.

The point is that Perth tuners are a 2.5 hour drive from home and then I need a bus ride to get home. So there is the best part of a full day gone and its repeated to collect the car. Two days off work costs me $2k before I start with the mechanics bill. Plus the favours I need to get the thing dropped off/picked up etc.

The last time it was tuned it was supposedly done properly by a supposedly good workshop in Perth but they couldn't diagnose a stuffed boost control solenoid and gave it back to me with low boost and 409rwhp on a hub dyno. The time before that with a different Perth workshop was even more of a train wreck.

I fixed the boost controlelr and the purpose of getting run up on a local dyno was to check it over on the assumption it was otherwise ok, not to tune it. But it made four more horsepower for four more pounds boost. Dyno disparities aside that isn't exactly winning.

Its got adjustable cam gears but I always viewed them as a nice to have for a few more hp, not a 20% gain. Nor do I really expect to find 80hp from some more ignition timing. Hence the thread asking for likely candidates.

For now it is:
Pull the exhaust and have a look.

Put it back on the dyno with the front cover off the motor and look at the tune.

But I don't have great hopes.

Johnnilicite: What would you expect the timing map to look like?

Edited August 1, 2015 by djr81

[Hadouken]

fark, can I have your salary?!

If you are on that much do then just get a limo back from the tuner.

Back to seriousness, go and get a tune.