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1974 gto 04-08-2004 10:30 AM

how much hp and how fast
I am 17 and have a 1974 GTo that I bought 3 years ago.
Just rebulit the motor and was wondering how much hp I would have and how fast it will be in the 1/4?
The motor is a pontiac 350 bore .030. !969 #46 400 heads, 9.5:1 compression, hardened seats, manley stainless steel valves, 1.5 roller rockers. Comp cams blueprinted ram air III cam "S". Cast pistons with 4 valve reliefs. Edelbrock performer intake. 800 cfm quadrajet. 1 5/8 full lenght headers. 2 1/2 in w/ flowmasters. 3.73 open rearend.
thanks for any help

killerformula 04-08-2004 12:26 PM

take it to the track and run it. YOu can calculate your HP by the 1/4 time or ET. you can even have it done for you for free online.


Croz 04-08-2004 04:11 PM

Someone with a desktop dyno may be able to figure out an estimate for your flywheel horsepower, and with the weight of the car and an idea of drive train loss you can find 1/4 mile times on the internet. However, the best way to know for sure would be to take it to the track or a dyno and find out. Much more fun that way as well.

tm454 04-08-2004 06:42 PM

can you spell N-E-W-B-I-E?
How much HP does the stock engine put out? You add on HP for duel exhaust and a mild cam and porting and polishing the heads helps a lot, did you flow the heads? I would guesstimate 350hp give or take a few. Probably 14 in the quarter with those gears. Go to the track with it and tell us what you run. Make at least 5 passes then get back to us with the results.


Rat Rods Rule!

1974 gto 04-09-2004 09:26 PM

the motor originally had 200 at the rear wheels

the motor is in my garage because i am still doing the body work on the car.

With the stock motor and a shift kit and the dual exhaust and 3.08 gears it ran a 15.67 @ 86 mph.

the tranny is a turbo 350 with a shift kit and now has a 2000 stall.

thanks for the replies and anybody with a desktop dyno i would really appreciate it

killerformula 04-09-2004 11:35 PM

can you really get a 373 open rear?


Ghetto Jet 04-10-2004 01:53 PM

Sure you can Killer, it's usually not a common practice. A posi unit just probably wasn't in his budget.


Beenaway2long 04-20-2004 11:16 AM

Close to 325 horse at the crank. I just built one using the 1968 #62 head (72 cc)/ .043 head gasket / zero deck height / cast pistons and comp ratio is 9.00 /1
Expect mid 14 passes. That motor weighs a TON.

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