New Setup Not Making Enough Power

[Toasty]

hey everyone

for those who read this post i am grateful for the time you take and hopefully you will have an answer for me.

i have recently installed a precision high flow turbo and have added supporting mods such as sard 550cc injectors, walbro fuel pump, intercooler, 3inch exhaust, running a greddy profec spec b and remap of the stock ecu.

my car is only making 184 kw atw. it should be making at least 200kw. first of all my car is running 16psi and dropping back to 14psi and i would like some helpful hints to find that problem. all hoses have been checked and tightened. what else could it be?

but my main question is about the dyno sheet of the air fuel ratios. there is a dip in graph, i cant work out what it is. could you please help me out with this. tonight i will be hooking up my consult software and checking a few things and will have more info tomorrow.

thanks

aaron

[TTT]

that graph is the "after tuning" graph?

*crosses another workshop off the list*

[Toasty]

yes

[TTT]

mate that is crap.

don't worry about the power figure so much.

all dyno's will read different.

but that A:F graph is crap.

[Guilt-Toy]

There may be issues that are causing that dip with the ECU or the way it is able to be tuned etc etc....

With a power fc it would be easy to remove that dip.

Its not really fair to go blaming the tuner and give them a bad wrap for something thats probly not even his fault.

Yes it is running pretty rich at 5,500 rpm and he would never blow that engine up. but there could be issues that are causing this that the tuner had to compensate for.

anyone got any other afr graphs for remapped rb20 computers?

[mad082]

well it is a rb20, so there is the first problem, LOL.

i assume you are running a manual boost controller? if yes, then there is the cause of the boost drop.

the afr's could be a fair bit leaner. they are close to 11 but could be up around 12.

it also depends on how much timing they put into the car, what compression you are running (how strong your motor is), etc.

[Blitz]

  mad082 said:

well it is a rb20, so there is the first problem, LOL.

i assume you are running a manual boost controller? if yes, then there is the cause of the boost drop.

Actually the first post says he is using a Profec B Spec II

[Toasty]

its using a greddy profec spec b and its a drift car so they have tuned to run rich. timing i will check tonight. it was running 15psi and dropping back to 12psi on the bleed tap style and made 174kw.

[mad082]

  Quote

Actually the first post says he is using a Profec B Spec II

yep, my bad

[TTT]

see it helps that you mention it's a drift car.

Then I wouldn't have said it's crap because it's tuned and still rich.

Speak with CEFFIE from these forums.

he burns his own remaps so he may be of some assistance here and may have come across it before.

[CEF11E]

hehe

I can offer a bit of advice,

The dip in the AFR's have been put there for a reason however they are a bit over emphasized. I will explain...

The dip to 10.5:1 happens at exactly 4000rpm, this is where you are hitting full boost. with a turbocharged engine you will be at peak volumetric efficancy at full boost and peak torque almost instantly after. you are most likely to suffer detonation at this point so adding fuel (to a certain extent) will reduce the possibility of detonation.

this is what has been done.

also just by looking at the power curve you can see that timing has been reduced between 4200 and 5600 rpm. seeming as you are running 16psi as a rule of thumb with 98 octane BP ultimate you should be running around 18deg at peak torque and then 19 and 20 deg in the following cells.

this is due to the engine becoming less volumetrically efficant at higher RPM (that combined with the fact that boost is tapering off)

I would be happy to have a look at the remap for you and see what needs doing to correct it.

(QUICK EDIT)... you should be able to safely run more boost. looking at the way boost is ramping up you are only just in the efficacy of your compressor. 17psi would make a lot more power especially if you were able to hold it to redline

[Toasty]

if i can get the boost drop sorted i will definately go for 17psi. but a quick list of things to check would be good. could it be the stock actuator?

[mad082]

it could be the stock actuator, it could be a restriction caused by the intercooler, the dump pipe, the cat or a muffler. some intercoolers, dump pipes, mufflers, cats flow better than others, but it does just seem to flatten out at about 14psi from 5600 onwards so it may be be in the settings of the controller. it only holds 16psi for for 100 or 200rpm.

[TTT]

man.. he must have sensed his name mentioned.. hahahaha

[TTT]

you say 3 inch exhaust.

what exhaust?

what dump pipe?

what cat?

[Toasty]

i am not sure what cat is on there. the dump pipe isnt split however it does make more room for the wastegate. its all mild steel.

[mad082]

the cat could be the problem, but the boost doesn't seem to taper of much as the rpm rises. after 5600rpm it doesn't really drop much.

[CEF11E]

the boost tapering off is not a restriction it is related to the controller setup and I am betting the controller is getting its boost reading from a nipple on the front of the compressor housing. if placed past the elbow by about 30cm you will get the most stable reading

[Toasty]

could the boost drop be solved by increasing the gain on the boost controller?

cef11e your are right about the nipple on the compressor housing.

Edited August 6, 2007 by Toasty

[GTAAAH]

Is it a highflowed 32 or 33 turbo?