Weakest Link

[Kaido_RR]

Hi,

I have an r33 gts-t with a hks gt2835 pro s and all supporting hardward, run by an apexi power fc

at the moment im making

320rwhp @ 12psi

and

337.7rwhp @ 16psi

now i am happy with my tune but not happy with the overall hp figure, ive done a search and found other people are making much more power with the same power and same mods.

my question will be is, im running a custom fmic and piping

now i know for a fact my piping has been cut and rewelded to fix my car, and the overall design of the piping looks average, also im using a china cooler. could this be casuing a flow issue and therefore giving me a lower power?

also i have a feeling that one section of the piping, may not be complete smooth on the inside possible causing turbulent flow

-michael

[R31Nismoid]

To see if the cooler is the problem.

Just measure the pressure before the I/C and then after it.

If there is a drop, then you have a problem

[Kaido_RR]

To see if the cooler is the problem.

Just measure the pressure before the I/C and then after it.

If there is a drop, then you have a problem

Would this have to be done on the dyno? and im guessing my tuner should have the tools to measure this?

thanks for the reply

[paulr33]

what exhaust

can u post up the dyno sheet

[Kaido_RR]

what exhaust

can u post up the dyno sheet

will post up dyno sheet asap!

im running HKS split dump (which come with the turbo kit) Trust front pipe (im guessing its 3 or 3, 1/2inch), and HKS cat-back (again guessing size 3 or 3, 1/2inch)

[Kaido_RR]

dyno sheet

[paulr33]

id be interested to see the IGN and INJ maps

also afr on the dyno plot would have been helpful

[Kaido_RR]

id be interested to see the IGN and INJ maps

also afr on the dyno plot would have been helpful

is it possible to get a print out from my tuner of the IGN and INJ maps ? i have been meaning to get a printout with the afr, i may do that this week if it will help find out wat the possible problem could be

[paulr33]

you can just view them yourself and write them down

setting, ign map

write them down into a 20x20 excel sheet

takes about 15 minutes

[R31Nismoid]

' date='3 Sep 2006, 11:29 PM' post='2459745']

Would this have to be done on the dyno? and im guessing my tuner should have the tools to measure this?

thanks for the reply

Yep, they should be able to do it without to much of a drama

[Kaido_RR]

hmm,

im getting abit worried about my result

the other day my mate how has a s2 r33 with a highflow turbo got 240kw @ 16/17psi and he had issues with the turbo itself (needs to be reported or something)

this is something like 10hp less than me :S and im pretty sure the 2835 is bigger than a highflow

[Kaido_RR]

Also,

i've been thinking about the issue with my I/C piping and Cheap Cooler.

the friction lose in the pipe itself could be causing an increase in the TOTAL HEAD, resulting in a drop in overall pressure. How great would the pressure drop need to be to affect power?

[paulr33]

well i think it goes that if you are running 10psi and the guage and actuator read from the compressor outlet or before the intercooler and intercooler core causes a 3psi pressure drop then there will be 7psi pressure in the manifold past the intercooler, which means less "boost".

[Kaido_RR]

well i think it goes that if you are running 10psi and the guage and actuator read from the compressor outlet or before the intercooler and intercooler core causes a 3psi pressure drop then there will be 7psi pressure in the manifold past the intercooler, which means less "boost".

thanks for that info paul,

i think im going to have to look into this issue more, as i can see its the only issue why my power figure is lower

[paulr33]

a few rwkw lower would be acceptable but not 20rwkw to 30rwkw from pressure drop. it doesnt sound right, its too much. try a dyno run with the exhaust dropped.

[Kaido_RR]

got the AF printout today

was a constant 11:1

[Adriano]

Was it the same mixturs at both boost levels?, I doubt it is the intercooler and piping, it would have to be pretty bad to lose that sort of power, i would be looking at the ign table, you could do a run on 12psi on the street, datalog the load cells, then do one at 16psi,look at how much timing has been removed to allow for the extra boost, should only be about 4deg, you can measure pressure drop in the intercooler system with a boost gauge, hook it up to the manifold and see how high it goes, then connect it to the compressor housing, should only see 1 psi difference. oh and its a bit rich, 12.2 should be fine for that power level.

[BHDave]

There's nothing too wrong with the power you are making considering the boost run and the a/f ratio. I'm assuming stock cams?

Get cams, watch as the car spits out another 25-30rwkw at the same boost and should just scrape 300rwkw with a bit more boost.

Ive seen a stock cammed rb25 with 2835proS make 269rwkw with more boost and a bottle of octane booster, but the same car is only making 256 on 16psi and pump fuel. It also uses a china intercooler.