Thread: small block

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i have a chevy 350 small block bored 60 over floating rods double humps heads 1.5 roller rockers 517/543 lift mechanical cam and a holley single plane intake with a 700 holley double pumper its not making no power the motor is in a pontiac grandprix 1986 it had a v6 in it do u all think it could be the rearend it have the v6 backend in it and it one tire but i think it should still burn the tire off of it what do u all think that i have a wrong combanation

What gears are you running in the rear? With that set up you should be"burning rubber" with a set up high gears like 2:73 and with low gears of 4:11 you shouldn't have any tire left.

i dont know but its just not making no power what do u thinkit might be

What pistons are you running, and what cc heads? What ignition? The V-6 metric cars all came with anemic rear end gears, usually in the 2.73 range. Is the engine running rich, lean? What do you have the timing set at? Need a bit more information to decipher the problem....

silv-o-lite hypereutectic pistons with two valve relief 64cc heads double humps head hei ingnition and how do i now if my push rods are to short

Originally Posted by demetrice askew

i have a chevy 350 small block bored 60 over floating rods double humps heads 1.5 roller rockers 517/543 lift mechanical cam and a holley single plane intake with a 700 holley double pumper its not making no power the motor is in a pontiac grandprix 1986 it had a v6 in it do u all think it could be the rearend it have the v6 backend in it and it one tire but i think it should still burn the tire off of it what do u all think that i have a wrong combanation

How much stall speed do you have?

cam duration is adv.278/288

stall speed is 3000

Originally Posted by demetrice askew

cam duration is adv.278/288

What is the duration at .050?

Pull all the plugs and do a compression test. That's the info I want to know.

Originally Posted by techinspector1

Pull all the plugs and do a compression test. That's the info I want to know.

I guess I "assumed" he had already done this.You know what they say about people who assume.

Swell.....

This is just some stuff to think about...
Your cam has about the same specs as a Performer Camshaft. This is intended more towards low to mid-range torque. The single plane intake isn't helping lowend performance matters. Same issue with the double pumper carb. A dual plane intake and vacuum secondary carb would be better matched to your cam. What distributer are you running? I hope it isn't a computer controlled version.
What tranny do you have? The stock 200-4R?
I wouldn't be surprised to see that your rear gears are around 2:56's... A boggy motor will have lots of issues spinnin those tall gears...
Mark

Originally Posted by astroracer

This is just some stuff to think about...
Your cam has about the same specs as a Performer Camshaft. This is intended more towards low to mid-range torque. The single plane intake isn't helping lowend performance matters. Same issue with the double pumper carb. A dual plane intake and vacuum secondary carb would be better matched to your cam. What distributer are you running? I hope it isn't a computer controlled version.
What tranny do you have? The stock 200-4R?
I wouldn't be surprised to see that your rear gears are around 2:56's... A boggy motor will have lots of issues spinnin those tall gears...
Mark

"Your cam has about the same specs. as a Perfomer camshaft".
With .517/.543 lift I highly doubt it.Plus it is a mech. stick.

Originally Posted by erik erikson

"Your cam has about the same specs. as a Perfomer camshaft".
With .517/.543 lift I highly doubt it.Plus it is a mech. stick.

Ahhh... skipped right over that... Thanks. That makes a BIG difference. The cam you have is your problem (along with the steep gears). Your engine is WAY over cammed for any decent street performance. The cam you have right now doesn't even start to work until the motor gets above 3000 RPM.

Here is the description for a cam similar to yours from the Crane website...
"PERFORMANCE USAGE, GOOD MID-RANGE TORQUE AND HP, BRACKET RACING; HEAVY, PRO ET, SUPER ET, ETC., AUTO TRANS W/3000+ CONVERTER, 10.5 TO 12.0 COMPRESSION RATIO ADV. BASIC RPM 3200-6800"

Not a good combo for a heavy, undergeared car. Combine that with the single plane intake and big carb and you have no bottom end work with. No low end torque is the culprit and that is why you say it feels "under-powered".
If you want a fast, drivable car on the street you need to build lowend torque and maintain high fuel velocities. You need a new cam, intake and carb to get you there.
What exhaust are you running? Headers and a good 2 1/4 to 2 1/2" dual exhaust with an "X" pipe. That would be another step in the right direction.
Mark