Low on power - ideas?

[Guest]

Any ideas on what could be the problem? Link to the car is in my sig. Just got dyno sheet today and its 226.4kw at fly. Its running 20psi with following mods. V7 sti shortie, sti gaskets, v6 sti heads, vf22, 440cc injecs, twisted, fmic, 3" turbo back, walbro, external reg and g4. Most cars run 220-230 atw some on lower boost with this set up.

Will upload pic of dyno soon.

[lachlan]

that is about the limits of 440cc injectors bro .

crappy exhaust manifold ? crappy intake ? crappy intercooler ? crappy tune ? what kinda dyno all of those things = more boost and less power

[Marky]

Was gonna say the same about injectors, 440\'s on anything else means around 300hp crank (normally)

Sure yr sure he does flywheel hp? Do you have anything else to compare to on the same dyno?

Its a pretty inaccurate guess - torque you can be pretty accurate with flywheel figures but HP just means "pluck a figure out your ass and muliply wheel hp by this"

Hell if I use the 30%ish drivetrain loss the net reckons is fair for a 4wd on my car I get the same flywheel power as you and we know that isn\'t accurate haha

[Guest]

440cc p1 injectors max 200-210kw atw. P2 at 230kw atw ish.

V5 stock mani no issues there and ej25 headers which gave a gain untuned.

Other dyno sheets from him all say power at engine. On virtual dyno it comes out around the 180kw atw mark with correct rolling od/weight and so forth.

[B4 2000]

Post sheet up?

[lachlan]

im highly dubious of 440s making 230 kw . not on a respectable dyno anyway

[titian]

What was ambient temp when dyno was done?..It is very hot around the country now with lowish humidity. This can cause percieved low power due to less dense air in our current Highs of around 1020 to 1030 Mbar.

Maybe? ???

[titian]

 lachlan said:

im highly dubious of 440s making 230 kw . not on a respectable dyno anyway

Easy to get 250 or 260 on 440 injectors Just increase the FPR a bit Say around 60 psi (4Bar)

[Guest]

 lachlan said:

im highly dubious of 440s making 230 kw . not on a respectable dyno anyway

Im not going to dispute that youre entitled to your opinion, Ive got sheets that say otherwise.

Trying to scan atm fucker aint working hold fire.

[Guest]

Virtual done tonight anywhere between 10-20deg would have to check but cbf.

[titian]

Top chart in 4th (Gary Capper) Other chart in 3rd. Therefore difference. Also Are they both Power runs? or Check tune? ???

Also time taken to "run up" can give these differences. Both charts reveal good power though.

What is your concern? Is your bumo meter detecting a difference? Sometimes thats also a better indication of performance.Usually better than a dyno! ;D

[titian]

Nb Garys dyno correction factor for Crank power is not accurate either. Hasnt been for years!

[lachlan]

yeah thats the concern . those graps are stated on them @ engine . id be worried too if i did all that and got 10 kw more than stock

also the boost/afr graph leaves a bit to be desired

yeah crank the fuel pressure true .

the bathurst gtr ran nismo 555cc injectors. at 115 psi base rail pressure lol . add on the nearly 30 psi boost to that and shes getting up there

[Marky]

ok, does he have a chart for a stock car on hand to compare with? would give you an idea over stock since youd have a more accurate starting point of 205kw fly for example to work back from in an approximate way

as has been said a few times the fly figure is 100% just an arbitrary multiplier, does he multiply by 20%, 50%, its just a random (well, educated) guess what the losses are.

whens the next auckland dyno day? haha

ive seen literally 50kw differences between different dynos, car itself keeps the same pace so its not losing power (even jokers gtb did this i think?) take the figure with a grain of salt, let a 1/4 time speak for itself until you get an apples with apples comparison at a dyno day or something

[Guest]

Most stock stis are approx 170-180kw atw tmic etc. There isnt really a difference between the two dynos other than ones at the wheels ones engine. I dont think it matters that its in third I set up the gear ratios and the final drive so it calculates it along with weight and everything else and roughly its pretty similar.

Its a massive diff when similar mod cars run 220-230kw atw on all manner of dyno which is compared to the same figure at fly. Thats my concern.

Its faster than it was but I wasnt shocked when I first drove it. I thought it wasnt a hell of a lot faster than old libero which was 160kw atw. Not as fast as mates legy which was 234kw atw on same set up vf22/fmic/boost but p1 gtb heads not sti.

Would explain why I cant utilise launch control and pull second it just doesnt have the power to pull it through even with 10psi.

[fbssub1]

ok what fpr pressure set at, what the duty cycle of injectors, and your also considering a larger turbo correct, launch control with a vf22 now they a laggy turbo better top end than bottom end and you want slow top end for economy,Clint you cant have power at both ends you set up for one or the other, the other thing IC piping diameter from turbo to cooler and cooler to intake and intake size all these diamensions will affect lag, check for exhaust leaks pre turbo as that will also slow spool up time, pi gtb heads any head work cam work, all need to know information to compare apple to apples and lets face it GCP is good not great but if thats all you have up there to use you use, but I would drive to Detech Tauranga for a quik run up on there dyno and see if it cant be tweaked

[Stoffa]

It makes me stop wondering why my $20K rebuild was making less power than yours.

[Marky]

Just idle thinking while work was quiet, you\'re right - somethings got to be hinky with it

The virtual dyno things are a good ballpark figure (not like exact but gives you a reasonable idea, same as a drag calculator I guess), and as the 226kw flywheel figure is multiplied by whatever figure - so say about 180kW wheels (once divided by the 1.2 or whatever he uses for driveline loss) so the two match up more or less

Without any faulty components to point the finger at it could be well worth a second opinion on the tune etc I suppose - realistically should be seeing around 200 ATW regardless of all the guff with injectors etc etc - there\'s a million examples of what a similarly modified sti will make on stock ECU let alone with a custom tune like yours.

If it was just the one dyno I\'d be saying "it just reads low" but backing it up with the virtual thing "kind of" discounts that argument a bit for me

[Guest]

 fbssub1 said:

ok what fpr pressure set at, what the duty cycle of injectors, and your also considering a larger turbo correct, launch control with a vf22 now they a laggy turbo better top end than bottom end and you want slow top end for economy,Clint you cant have power at both ends you set up for one or the other, the other thing IC piping diameter from turbo to cooler and cooler to intake and intake size all these diamensions will affect lag, check for exhaust leaks pre turbo as that will also slow spool up time, pi gtb heads any head work cam work, all need to know information to compare apple to apples and lets face it GCP is good not great but if thats all you have up there to use you use, but I would drive to Detech Tauranga for a quik run up on there dyno and see if it cant be tweaked

Unsure on fpr removed guage. Need to check d/c will do tonight. Id like to find out where the power is before upgrading turbo. Piping is 2.5" with 12" of 2" off turbo. I chopped a lot of piping out with the flip/twist wouldnt think thats an issue. 3" Intake and good intake temps. Its got low power all over its not laggy imo. I would rather power later in rev I can drive around lag its a road car.

Chris people make 220-230kw atw on tweaked stock stis just need a g4 thats my point this setup works just not this one lol. Yours was done properly in every aspect but most of the money went into reliability didnt it? Cars vary all the time but this power isnt uncommon on various dynos at the axles.

[Guest]

Yea marky my point exactly thats why I wanted to do the virtual dyno its freakishly close and people swear by it compared to rolling roads.

[ADIKT]

I pulled 227 atw with 440s. peaked at 89% inj duty lol that was vf30 also.

Talk to garry and explain your not happy with it? and see if he can revise?

[Pappu1]

 ADIKT said:

I pulled 227 atw with 440s. peaked at 89% inj duty lol that was vf30 also.

Talk to garry and explain your not happy with it? and see if he can revise?

WhT AFR were u tuning to?

I maxed my 565cc inj on 235kw and running low 11afr

But had good power curve peaking at round 5.5k and almost table flat till 8k

Have to dig out plot to confirm

Anyway I Wud say come to the next dyno day and have a comparison

I have never been eased with gcp tune and had same issues when had mine done there a long time back

Never seen a car back his claimed result on any dyno day always falls a lot short and there is always a race excuse to back up the pathetic show lol

Even members here on cs dyno day had same differences Inc the times I had it done there and wen on a dyno day on his own dyno the car made a lot less

[ADIKT]

 SP00N']

[quote name='ADIKT said:

I pulled 227 atw with 440s. peaked at 89% inj duty lol that was vf30 also.

Talk to garry and explain your not happy with it? and see if he can revise?

/quote]

WhT AFR were u tuning to?

I maxed my 565cc inj on 235kw and running low 11afr

But had good power curve peaking at round 5.5k and almost table flat till 8k

Have to dig out plot to confirm

Anyway I Wud say come to the next dyno day and have a comparison

I have never been eased with gcp tune and had same issues when had mine done there a long time back

Never seen a car back his claimed result on any dyno day always falls a lot short and there is always a race excuse to back up the pathetic show lol

Even members here on cs dyno day had same differences Inc the times I had it done there and wen on a dyno day on his own dyno the car made a lot less

Will dig my plot out and get back to ya

EDIT: Found my plot from TP dyno day. 11.5 AFR full boost

[titian]

You could get dwight to tune it He the best there is with the subaru ;)

[Pappu1]

Any chance to post up the plot

Sounds like a nice setup!!

Wat Ecu was it?

Also if he were to get it retuned Wud gcp be refundin him for the lacking tune?

 ADIKT']

[quote name='ADIKT said:

I pulled 227 atw with 440s. peaked at 89% inj duty lol that was vf30 also.

Talk to garry and explain your not happy with it? and see if he can revise?

/quote]

WhT AFR were u tuning to?

I maxed my 565cc inj on 235kw and running low 11afr

But had good power curve peaking at round 5.5k and almost table flat till 8k

Have to dig out plot to confirm

Anyway I Wud say come to the next dyno day and have a comparison

I have never been eased with gcp tune and had same issues when had mine done there a long time back

Never seen a car back his claimed result on any dyno day always falls a lot short and there is always a race excuse to back up the pathetic show lol

Even members here on cs dyno day had same differences Inc the times I had it done there and wen on a dyno day on his own dyno the car made a lot less

Will dig my plot out and get back to ya

EDIT: Found my plot from TP dyno day. 11.5 AFR full boost