Getting Next Tune

[SkyDragon]

Going in for a tune in the next month or so after a dissapointing result last year.

Car is R33 gtst S2. My mod list includes;

RB25 Stock internals

HKS 2835 pro s

HKS FMIC

HKS pod

3 " turbo back exhaust

hi flo cat

Sard bov

Wolf V500 ecu (using as boost control)

With this setup I made 227rwkw. Expected at least 260rwkw. Boost is hitting 1.1 bar

The difference in the next tune is I will have Nismo 555cc injectors. However I am debating on whether I should get some cam gears to allow for finer advancement/retarding of timing? If so should I get both intake and exhaust? Or just one or the other

From reading the forums joeyjoeyjojo is making 270rwkw with a very similar (if not the same setup - except he uses exhaust cam gears). I do not want to return from the tuners this time with the same kw and waste more $$$.

Info appreciated.

[allthewaytotheskyline]

ya know...im having the same/similar issue at the moment.

but im getting 250rwkw but supposidly have hit a wall with flow of intercooler so ive changed my intercooler.

who is doing your tuning by the way??

btw i think joeyjoejoe has it boosted to about 18 psi.

[R31Nismoid]

So what trouble shooting have you performed?

ie...

Do you know the exhaust/dump/cat isnt a restriction?

Sure the BOV isnt slightly leaking, piping etc?

Current cam timing is correct? (cam belt isnt a tooth out)

Tune is decent? Perhaps not enough fuel?

just because you aren't making "x" power doesn't neccesarily mean much.

Remember you have VCT on the intake... I ran a stock head, cams etc to well over 300rwkw. I bet there is something else wrong

[SiR_RB]

you'l need to upgrade your fuel pump

[SkyDragon]

r31nismoid,

I know there is no restriction with exhaust/dump/cat. This has been checked on a couple of ocassions now.

Cant confirm 100% but I am pretty sure the bov is not leaking

Cam timing is something I cannot confirm and this is the reason why I am considering cam gears as at least while the cover is off we can see if there is a tooth out or cam gears are worn.

For the tune I need to trust the tuner and I didn't have 100% confidence in my last tuner, hence the reason for going somewhere else. The only feedback I got was that the car began to ping when putting more timing into the tune, hence no more than 227rwkw could be reached without risk of detonation. They told me it was either a timing issue (cams) or bad fuel.

Based on this I guess cam gears may be a worthwhile investment?

alltheway, my tuner is in WA. I am using a different tuner this time round

[SkyDragon]

you'l need to upgrade your fuel pump

Opps forgot to mention that - I DO have an upgraded intank fuel pump

[R31Nismoid]

Cam gears wont be causing you to be magically down 40rwkw.

So no.

Best cam gears are going to do its alter the power curve and maybe net a little bit of power in some instances.

[Dose Pipe Sutututu]

saying that 227rwkws from a RB25DET running only 1.1Bar is quite decent, remember also different dynos read different values.

Would be good if you posted up your dyno results too!

A/F vs RPM, Boost vs RPM, Power vs RPM

[SkyDragon]

Dyno chart attached

20090715163644.pdf

[Adriano]

Im assuming the injectors were limiting the power, why it is running 1.1 bar to max out the injectors is the real question.

You need to remember that setting up the cam gears is a bit of a time consuming process in an rb, as the cas need to be removed every time you want to adjust, so it will cost you a bit in dyno time.

[Dose Pipe Sutututu]

do you have a a dyno sheet with the A/F?

That power curve look good, as in the person who tuned your car knows what they're doing.

What is the MAX injector duty cycle registered on the powerFC?

[R31Nismoid]

As do 555's limit power?

[SkyDragon]

Im assuming the injectors were limiting the power, why it is running 1.1 bar to max out the injectors is the real question.

You need to remember that setting up the cam gears is a bit of a time consuming process in an rb, as the cas need to be removed every time you want to adjust, so it will cost you a bit in dyno time.

Apparently the stock injectors were in the mid 80% for duty cycle. The tuner said this was not the problem. He kept stating that the car began to ping when putting more timing into the tune indicating bad fuel (I was running BP 98) or bad compression?

I did not get much in the way of feedback hence the reason I am not going back. I have had others point out that I should do a fuel injector upgrade which is what I am doing now, however tuner does not think this was the issue. I am just thinking if the timing was an issue then maybe cam gears, a new belt and resetting the timing may fix?

However I dont really know what prob I am trying to fix! Thats the frustrating part!! Just looking for more power from the 2835.

johnnilicte, I do not have a dyno graph with AFR's.

Any other comments/suggestions?

[Flecher]

i reckon replace new coil packs?

[R31Nismoid]

^ based on what exactly?

[Dose Pipe Sutututu]

i reckon replace new coil packs?

R31Nismoid, I sense KB warrior that doesn't know anythibg

If his coil packs are/were fcked you will see ripples in the dyno graph.

1.1 bar and making that power figure is completely normal, I'm running 1.3 on a tiny turbo and only make 223rwkWs, but saying that on a different dyno clocked up 247rwkWs

[SkyDragon]

i reckon replace new coil packs?

Already done - I have split fires

Dunnno how that would be related. If ignition was not occurring correctly I would see inconsistency in boost/power levels. The car holds boost and power fine, just wont go above 227rwkw with current mods/tune

[SkyDragon]

R31Nismoid, I sense KB warrior that doesn't know anythibg

If his coil packs are/were fcked you will see ripples in the dyno graph.

1.1 bar and making that power figure is completely normal, I'm running 1.3 on a tiny turbo and only make 223rwkWs, but saying that on a different dyno clocked up 247rwkWs

johnnilicte, Interestingly I was getting 229rwkw with a HKS 2530 from 11 psi! I had the same mods excluding the wolf (I had piggy back ecu)

Now I have a 2835 and wolf ecu and lost 2rwkw!

[Dose Pipe Sutututu]

was this on the same dyno? if you could, ask for the boost vs rpm a/f vs rpm from your tuner, that way we all can work out what's going on.

[EliSun]

around 4750rpm is where your curve starts to fall

it's definately some kind of flow limitation

always start with the cheapest and easiest possible solutions:

if you've got a 2835, surely you'd have the full 3" exhaust from the turbo back, high flow or no cat, straight as possible.

check your fuel pump and ensure that it's grounded properly and is getting the correct voltage.

check your sensors etc.

does the Wolf V500 an AFM type ecu?

limits of the stock rb25 afm are around around 230rwkw, alot of people upgrade to a z32 using a power fc at this stage.

1.1 bar should be enough boost, once you've got your 550cc injectors in, get an adjustable fuel pressure regulator and up the fuel pressure a bit.

Edit: oh yea, also what type of "aftermarket fuel pump do you have?"

bosch 044s are much much better than their 040 brothers.

Edited July 16, 2009 by EliSun