dissapointing dyno numbers.....

[stk6bngr]

So i dynoed my car on thursday the temp in the shop was 97.8 degrees 1 percent humidity.

my car dynoed at 391 hp with 458 ft lbs of torque at 19.8 psi 21 degrees of timing on 100 octane.

my set up is pt54 with .63 housing. 3'' thdp, brian h. tranny full billet rollerized trans brake with a 2800 stall 9.5 inch ptc converter from dusty, walbro fuel pump, 3 inch ss atr dual exhuast, hot wire kit, ported stock iron heads, 60lb mototron inj. with tt chip.

the dyno graph shows i was running way to lean up top 14.3 to 1 so i tried to add 10% still to lean. 3rd pull i added 20% a/f didnt change. bumped up fuel pressure and it was good till about 5500 rpm and the fuel pressure dropped about 20 psi....

do i need to get a bigger fuel supply line?

 

[bmackinnon]

sounds like the walbro is going weak.... factory fuel lines can support alot more than that....

 

[stk6bngr]

do you think i should get a double pump setup?

 

[bmackinnon]

I'm no genius, but perhaps the Supra TT Denso pump would be a better option at your level? Double pumper would be plenty, but probably overkill.... Denso pump has plenty of capacity... something on the order of 700-800 hp..... neither is a straight plug and play, but the denso install would be cheaper and easier.... harness is available from racetronix and the install itself requires very little (if any) modification... plenty of info here with a search... :smile: First one I came across... there's alot more, too.... search 'denso install'...

http://www.turbobuick.com/forums/ge...2481-280-lph-supra-fuel-pump-installed-8.html

 

[JDSfastGN]

Those numbers are actually pretty good imo. 20 psi and stock cam? was it a dynojet? mustang? superflow? Hell I only put down 427/458 on a superflow and went 122 the next weekend in warm air. (was my old combo with a 204/214 and PT61)

 

[bmackinnon]

Those numbers are actually pretty good imo.

I thought so too, but the fp is dropping, so something's amiss....

 

[JDSfastGN]

I thought so too, but the fp is dropping, so something's amiss....

he does need to fix that , but hell with a stock cam it probably is on the down slope of power anyways at 5500.

 

[we4Mateo]

Numbers don't soundbad to me either. I need 25lbs of squeeze with my TE44 to get 380hp. And every dyno is different. My stock cam stops making more power at 4400rpm.

 

[salvageV6]

With ported heads I'd want 30 more HP at that boost at least.

Any timing retard, logging tools etc.?

Lean shoulda been mean if it wasn't detonating.

 

[JDSfastGN]

With ported heads I'd want 30 more HP at that boost at least.

Any timing retard, logging tools etc.?

Lean shoulda been mean if it wasn't detonating.

Not sure how you can expect more with a stock cam and a turbo that would rather be a 25 psi. You need more usable rpm for more power with the current setup, plus without knowing what type of dyno it's all a guessing game. Were these big valve heads?

 

[salvageV6]

I dunno I made those numbers with a stock 150K motor no heads, at 23psi. on pump gas and alky. timing at 21 degrees.

With a TA62 very similar to the 54.

With ported heads I would expect a bit more even with a stock cam. and yes the type of dyno., any timing retard, and what timing was run, how good the port job was, would all be important to know.

With ported heads that turbo should be working just fine at 20psi.

I agree the stock cam. wouldn't need to be spinning at 5500 max. HP would be a bit lower.

They're not bad numbers by any means just not so good either.

 

[JDSfastGN]

I dunno I made those numbers with a stock 150K motor no heads, at 23psi. on pump gas and alky. timing at 21 degrees.

With a TA62 very similar to the 54.

With ported heads I would expect a bit more even with a stock cam. and yes the type of dyno., any timing retard, and what timing was run, how good the port job was, would all be important to know.

With ported heads that turbo should be working just fine at 20psi.

I agree the stock cam. wouldn't need to be spinning at 5500 max. HP would be a bit lower.

They're not bad numbers by any means just not so good either.

Do you have track times to correspond those numbers to though? Im not trying to be rude at all, and trust me I believe the numbers you got, but most dynos Ive seen are very optimistic. The 86 in our sig made 448 hp converter locked on a mustang dyno and ran 126 mph full weight with no changes. I bet most would have thought it would put down at least 480-500 to run the mph.

 

[salvageV6]

Seemed to correlate well with the mph and weight in the TCI calculator, I think it was even closer when I used IJames formulas.

I see he was on the same timing and 100 octane.

I locked my Vigilante converter so maybe that was the difference.

With a 100 degree testing area that could be a problem as well if a big fan wasn't in use.

I usually test a bit cooler.

At the last dynojet number of 425HP it ran 113.5 mph at 3900lbs with the 70 on it.

It was running about 110mph with the 62 at the 388HP level at 3900lbs.

I thought that was close enough to most calculators.

Hopefully more information regarding the testing and any datalogging will be forthcoming.

 

[stk6bngr]

the dyno used was a dynojet and yes it had a big fan in front of my car. no track times yet this was the first time the car was on a dyno, i had my powerlogger logging the runs but stupid me forgot to save them.....

i belive the intake valves r bigger but im not sure. only reason i put the car on the dyno was to get some actual numbers so i can get my car dialed in.

i have the fuel pressure set at 43 psi with vaccum line off like eric says to do and the thing does not want to idle in gear. then itll fall flat on its face and wants to stall when i get into the throttle off idle and spits out tons of smoke but when i mash the pedal and im in the power band it runs to lean and the fuel pressure drops 20 psi.


my car has basically stock everything except for what i have listed and stock intercooler. suspention is all stock... my goal is to be capable of high 9's but that costs lots of money so im slowly building it.

 

[aminga]

sounds like the walbro is going weak.... factory fuel lines can support alot more than that....

What he said.

If the FP is dropping you'd better get good at changing head gaskets.

 

[krom]

The dyno HP and torque numbers mean nothing, fix the fuel issue and go to race. I like beating dyno warriors at the track. My car will never see a dyno. Tune your car on the street, that is why they made freeway access ramps 1/4 mile or longer.

 

[jasjamz]

Do not trust a dyno wideband. Get your own. Test and tune at the track. Then put it on the dyno to see what the power comes out to be.

 

[Rebel]

Dyno's are good tune-up tools but not good tuning tools. Go to the track.

 

[stk6bngr]

well going to the track to tune will be hard because our track is only open on the weekends and i work weekends.. so i guess ill have to be creative hehehe

 

[G NASTY]

About what RWHP does a STOCK GN make?