jptaylor2

you can read my sig and determine what you want. im trying to figure out how much power my stock LO3 chip is robbing from me. my dyno #s from HESCO in birmingham are 311 rear wheel hp.

jptaylor

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1989 formula
jasper 350 (punched to 397ci)
trick flow twisted wedge heads
jacobs omni magnum ignition
isky cam
flowtech jethot coated headers
mufflex 4" mandrel stainless exhaust
no cat
holley 670
open element
custom fixed headlights
97 formula interior
macewen white faced gauges
3.42 posi rear end
baer racing 4 piston calipers front and rear
underdrive pullies
hard wired cooling fans
http://www.geocities.com/jptaylor2/FIREBIRD.html

Pablo

iTrader: (1)

JEEZ thats a big number
and on the stock chip!? that isnt conducive to performance i bet you are going way lean.
If it were mine id get a gm injector pod on there with 454 injectors with an external regulator, and DEFINATELY A CUSTOM CHIP
i wouldnt be surprised if you saw more than 50 hp more out of a custom chip andthe right injectors etc

jptaylor2

pablo

the power is in the heads. no kidding. before the trick flows my rear wheel was 265 hp. thats 46 rear wheel hp. as for the injectors im running the holley 670 with the 65lbs injectors. fuel pressure is set at 13lbs. i do know that the stock chip is killing me and i figured that someone on here has a similar setup with a chip and could give me a good reason to come off the money. also ive tried to find someone to burn a chip but no luck.

jptaylor

------------------
1989 formula
jasper 350 (punched to 397ci)
trick flow twisted wedge heads
jacobs omni magnum ignition
isky cam
flowtech jethot coated headers
mufflex 4" mandrel stainless exhaust
no cat
holley 670
open element
custom fixed headlights
97 formula interior
macewen white faced gauges
3.42 posi rear end
baer racing 4 piston calipers front and rear
underdrive pullies
hard wired cooling fans
http://www.geocities.com/jptaylor2/FIREBIRD.html

Pablo

iTrader: (1)

I dont see how you havent melted a piston yet, i cannot believe you managed to get that much hp out of 65 (actually less since you have it set lower than 15 psi) injectors. For that kind of HP you NEED some big block injectors and alot of fuel pressure. Id be carefull if i were you
but IMPRESSIVE numbers! more fuel + tuning should put you through the roof with that setup

Tas

what intake you got on that engine? and how is it a 397 now?
Tas

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AOL IM: superGRtaz
ICQ: 82881207

[This message has been edited by Tas (edited October 01, 2000).]

jptaylor2

first pablo

i know the #s seem high for the injectors but the guys at hesco said because the motor was lean it made more power(ran hot as hell before the constant dual fans)i quote
"lean = horsepower" i know thats a little cliche but its what they said. i thought about the 454 tbi but kinda shyed away because of a rich condition everyone was talking about. by the by i forgot to put that the heads have been worked(by me ) and sport 2.02 intake and 1.72 exhaust. i cant say enough about these heads. what fuel pressure should i put these inj. on.

second tas,

the intake is a '72 camaro 4bbl intake with the adapter. went to a site one time that said that it was the best by far and i found one(actually the whole motor) on ebay. i sold the block and heads separate and kept the intake and still made 15.00. as for the 397 that is what this program im running gives me when i plug in all the paramaters. when it was built the speed shop said it was 412.34 ci but i thought that sounded a bit large. i do know that the the block is a .090 over 350 as i have the paperwork from jasper(i didnt think you could do it either but they did) and it has been stroked and has a 400 crank. the 397 may not be exact but i figure its closer than the 412.

jptaylor

------------------
1989 formula
jasper 350 (punched to 397ci)
trick flow twisted wedge heads
jacobs omni magnum ignition
isky cam
flowtech jethot coated headers
mufflex 4" mandrel stainless exhaust
no cat
holley 670
open element
custom fixed headlights
97 formula interior
macewen white faced gauges
3.42 posi rear end
baer racing 4 piston calipers front and rear
underdrive pullies
hard wired cooling fans
http://www.geocities.com/jptaylor2/FIREBIRD.html

Pablo

iTrader: (1)

lean= melted pistons


i wouldnt go by what most speed shop guys tell you. The only reason youd run rich with bigger injectors is because your idle and part throttle programming is wrong. Your WOT programming is wrong too but it wont be so rich

91Bird305

Hey Pablo, those 454 injectors your talking about, what are they off of and i heard that the GM injectors on any engine are off set or something. SOmething about them not being very flow matched and I heard that injectors being flowmatched are very important on our kind of cars

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Eric Natzke
91 Firebird 305 TBI (dropping in a 355 summer of "01")
ASCD Ram Air Hood-3" custom exaust-Flowmaster 80 Series-No Cat-Edelbrock TES Headers (coated)-March Pulleys-TBI Spacer-K&N Open ELement-TransGo Shift Kit-B&M Supercooler 28,000 GVW-Hypertech Thermomaster-160 Stat-3:42 GM Gears-Auburn Posi Unit-Edlebrock Strut Tower Brace-MSD Superconducters-Accel Cap & Rotor
-Rapidfire Plugs-Pablo's Free Mods-265/50/R15 Tires-Emmison's all Gone

http://hometown.aol.com/J007Golden/index2.html

Dan W

Some math: (I made a mistake on the formula for displacement, here is the correct one... oops.)

(bore/2)*(bore/2)*3.14*stroke*#cylinders=displacement


A .090 over 350 with a 3.75" crank displaces 394 cubes.

I'd be talking with jasper if I were you to find out exactly whats going on and what parts were used. You are going to want a custom chip before you break something... you need to know your displacement to get a custom chip.

Exactly what cam are you using... lift and duration at .050 pls. Whats your compression ratio?

[This message has been edited by Dan W (edited October 03, 2000).]

[This message has been edited by Dan W (edited October 04, 2000).]

jptaylor2

dan thanks for clearing up the ci issue. i spoke with kelly at jasper on monday and he said that the 412 was a miscue like i suspected.he said that the actual ci displacement on my motor is 395.6 ci. i absolutely no good at displacement math and you seem adept at it so what breaks on the ci that i was just given. the cam is an iskedarian that has the same grind as the LT4 hot cam. the compression ratio according to jasper is 9 3/4 to 1. ive been spinning the hell out of this setup for nearly a year and havent broken anything major(knock on wood) but your saying that a chip would help to balance out the motor. any idea on the power im losing due to this setup. once i put in an L05 computer and it ran like a YUGO.

thanks

jptaylor

Dan W

Just guesswork here... but I'll give it a shot. I'll assume your motor should make 1.1-1.2 or so hp / cubic inch at the crank with those trick flows and the hot cam. I'd guess from 425 to 485 hp. (I dont know much about that intake so I could be way off)

You dynoed at 311 rear wheel... or 388 crank hp (assuming 20% drive train loss) So I'd bet you are loosing at least 35 (crank) hp but more likely 50 to 75 hp, maybe even a little more.

What is your base timing set at?

I think you are doing ok now because those heads are very efficant. (Your Brake Specific Fuel Consumption is low)... but still I think you are very under fueled.

I dont have the math to work from with me but I'm guessing that you would need 2-90# GM injectors (in your stock injector pod) at 15-20 psi to ultimatly see your full power potential.

That intake may also be holding you back some on top so it also depends on that unknown...

jptaylor2

dan i had the base timing set at spec 0 deg. I bumped it up to 12 and you wouldnt believe the difference. after the timing bump i tested the tps and it was off a little so i calibrated it to spec and again another big performance jump still for all the inches,heads and cam i still feel way short. by the by ive always run accel ignition coils and parts until a buddy of mine with a speed shop gave me this jacobs electronic omni magnum setup and it gave me an honest to GOD 850 more rpm and the throttle response is now instant.

jptaylor