dyno numbers with GN-1's and roller cam DISSAPOINTMENT

[forzfed]

My buddy's fully loaded stage II GN ran a 10.1@132mph on 9psi with a T-76 and a 1.53 60ft, it went 9.7@146 with 14psi and hanging the front tires off the ground for 500ft. The car revved to 8500rpm, with a huge cam, 620 lift.

 

[norbs]

Doing some math here 600rwhp@3700 lbs means your car will run 10.0@133 mph @14 psi boost on pump gas is this what your car runs? I can believe forzfed but your numbers are just too amazing for unported heads, please enlighten us on this combination.

"My stock stroke (but bottom end) with GN1's out of the box 212/212 roller 91 octane @14 psi made 593rwhp and 730@ 26 psi."

 

[smoke20]

Looks like poor Slim is missing 200 hp+@14 psi. I find those numbers awfully high for 14 psi. What size turbo are you running? UNported heads even?

My buddy's fully loaded stage II GN ran a 10.1@132mph on 9psi with a T-76 and a 1.53 60ft, it went 9.7@146 with 14psi and hanging the front tires off the ground for 500ft. The car revved to 8500rpm, with a huge cam, 620 lift.

I call bs on this too

 

[smoke20]

Going to disagree here, and, agree with Bison. My stock stroke (but bottom end) with GN1's out of the box 212/212 roller 91 octane @14 psi made 593rwhp and 730@ 26 psi. You need to work on your tune and get a dual nozzle kit from Julio, you'll be good to go after that.

think dyno added 200 HP for you. what a gift.

Most I made was 548 at 27 psi with a 218 218 rollor and fully ported heads and intake on e85

 

[bison]

My buddy's fully loaded stage II GN ran a 10.1@132mph on 9psi with a T-76 and a 1.53 60ft, it went 9.7@146 with 14psi and hanging the front tires off the ground for 500ft. The car revved to 8500rpm, with a huge cam, 620 lift.

This is highly unlikely. Chances are the boost was in the 17-19psi range on the 132mph pass and run for all it was worth (what ever amount of boost it would make with new wastegate closed off) on the 146mph pass. Making power to 8500 with a single 76 compressor on a 250ci engine isnt plausible either. Do you have any logs of this performance?

 

[bison]

think dyno added 200 HP for you. what a gift.

Most I made was 548 at 27 psi with a 218 218 rollor and fully ported heads and intake on e85

Insteads of looking at dyno hp numbers its easier to make conclusions car to car dyno to dyno knowing the fuel consumption. If a engine is using 300lb/hr of fuel (gasoline) its fairly safe to say its making 550-600hp. Dyno numbers vary day to day, climate changes, correction factors change numbers, but the fuel consumption per hp on a given engine or similar engine doesnt vary too much. Fwiw i made a little under 700whp@24-25psi on a decent stock stroke engine and on another decent one with lower compression ratio and 2* less timing with a different cam made about 625whp. The funny thing is the fuel consumption variance between the two was about 4%. Id bet if they could be run back to back on the same day they would be within 4% whp and not the 8% variance in peak whp. The average road hp would be even closer. If that 2* timing and the CR was bumped in the lower one they would probably be within 1%. If two engines running the same heads mor very similar heads and cam are using the same amount of fuel they are making about the same hp. There are things that will effect it but its not going to be a 100hp difference using the same parts and fuel consumption.

 

[forzfed]

This is highly unlikely. Chances are the boost was in the 17-19psi range on the 132mph pass and run for all it was worth (what ever amount of boost it would make with new wastegate closed off) on the 146mph pass. Making power to 8500 with a single 76 compressor on a 250ci engine isnt plausible either. Do you have any logs of this performance?

It's a 274, not 250. I've seen the logs. This was on a cold day, passes are usually in the 142mph range on that boost. As far as I know it's the fastest Stage car in Canada. The heads flowed 335 cfm on 500 lift, so at 620 I would think it would be more.

 

[forzfed]

Doing some math here 600rwhp@3700 lbs means your car will run 10.0@133 mph @14 psi boost on pump gas is this what your car runs? I can believe forzfed but your numbers are just too amazing for unported heads, please enlighten us on this combination.

"My stock stroke (but bottom end) with GN1's out of the box 212/212 roller 91 octane @14 psi made 593rwhp and 730@ 26 psi."

You probably know who built the motor. Well known guy in TO, and he believes in lots of cam.

 

[turbojosh]

with those 120's, I'd jump into e85 if you have the pumping capability. I got tired of jacking around with alky systems and the price of C16. Something to think about.

. Could of not agree any better! Def try that route since you already have a right size injectors !

 

[norbs]

Well, Slim I hope you get things together and get better numbers. This has been a very interesting thread, we have stage 2 cars running 9s @9 psi boost, unported gn-1 headed cars making the same power as stage 2 cars and no one believing anything at this point....

 

[SCOOBY DOO]

Well, Slim I hope you get things together and get better numbers. This has been a very interesting thread, we have stage 2 cars running 9s @9 psi boost, unported gn-1 headed cars making the same power as stage 2 cars and no one believing anything at this point....

If you're pounding your junk up and down the 1320 on a regular basis...you know what's possible...and what isn't.

 

[SCOOBY DOO]

Haterade PM'd me and said these HP and ET numbers aren't possible.

 

[Adrian87]

Lmao

 

[norbs]

Being Serious, Slim has to get back to the dyno and track and figure this out.

 

[slimtastic]

well at this point ive been doing some digging on the motor and at this point the ive verified proper valve spring installed height
(1.800). checked all compression (125-135 psi on cold motor with 5 compression strokes-throttle closed)

push come to shove i might go back and degree the camshaft just to verify the "straight up" setting

i did run across one injector that wouldnt drop the idle to crap nearly as much as the others when unplugged...it has solid positive and a good pulsed ground. shortly ill be running down this path and see if i have gunk or somthing clogging up the spray pattern. ive checked the plug and the piston top, finding no signs of knock and the plug looks to be washed down a little from fuel....i sure hope im not getting trash from the stock fuel liness into my 120s.

kinda thought with the over kill sizing that the 120's would be able to pass light debris but i guess not. ill let yall know if i find anything more

 

[forzfed]

Well, Slim I hope you get things together and get better numbers. This has been a very interesting thread, we have stage 2 cars running 9s @9 psi boost, unported gn-1 headed cars making the same power as stage 2 cars and no one believing anything at this point....

I said 14psi to run 9's, 9psi to run low 10's. On 18psi it tore the rearend out of it.

 

[norbs]

I said 14psi to run 9's, 9psi to run low 10's. On 18psi it tore the rearend out of it.

OK I got carried away, but that car still sounds like a beast...........

 

[EVIL]

Any update?

D

 

[L8TRH8R]

He is talking about straight pump gas, not running alky. Great numbers though! What size turbo were you running?

billet 6765

 

[L8TRH8R]

think dyno added 200 HP for you. what a gift.

Most I made was 548 at 27 psi with a 218 218 rollor and fully ported heads and intake on e85

This car has been on two different dyno's both dyno jet last time made 680 @ 21.5 psi. Stock bottom = stock stroke NOT STOCK GM PIECES. It will be featured in GM High Perf this winter.