the next thing im working on is my drivetrain but i dont just wanna jump on that without knowing what hp. and tq. im making or atleast a rough estimate. the engines already rebuilt and on the road daily and what i was shooting for was about the 300hp 350tq range. but to have an idea id like to ask you guys to get some opinions on what i might be making while i look for a transmission to rebuild. i should be able to give you all the information you need. its a 69' sbc 350 out of either a camaro, chevelle or, nova. stock crankshaft and heads. flat top pistons 2 valve reliefs. bored .030 over. comp cam part# 12-305-2 429int. 438ex. lift. edelbrock performer rpm manifold. probably 9:5.1 comp. maybe 10:1 but probably not. anything else i should be able to tell you.
horsepower guess
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the head casting numbers are either 3927185 or 3986339. its the backwards L. for cam specs I have a hydraulic flat tappet cam with a basic operating range of 1200 to 5200 rpm. Duration at 050 inch Lift 203 int./212 exh... Advertised Duration 246 int./263 exh...Valve Lift with Factory Rocker Arm Ratio 0.429 int./0.438 exh... Lobe Separation (degrees) 110..Grind Number 246PE. sorry it took so long to get this just been a little busy.
anyone wanna just throw some numbers out there? im not trying to get dead on numbers just an estimate number.
What CC are your heads? A good way to figure out what your block is from is the VIN number at the cylinder head pad on the right from passanger side of the block. But as you mentioned you have flat top pistions with 2 valve reliefs your looking at 10 to 10.5 to 1 depending on the chamber size.
If your heads a the 3986339 then you need to ditch them. They are 307 heads which are junk. 1.72 intake valves 1.50 exhaust small ports and such.
The 3927185 call for 68-73 307,350 heads but they also call for 69 327 heads same size valves as mention above on the 307 heads. Your heads are your biggest restriction right now. Everything on your engine sounds like a nice matched street engine but your heads are killing you big time. At the crank your probably looking at maybe 275?
Swap your heads for double humps or Vortecs and your probably knocking on the door of around 320 to 330. A stock rebuild with a shift kit will hold your transmission up nice to atleast 400 hp. My dad and I used to drag race a 1964 Chevelle Malibu SS with a built up 350 bored 60 over running low 11's full interior car with a stock rebuilt transmission and a nice shift kit. transmission was a turbo 350
If your heads a the 3986339 then you need to ditch them. They are 307 heads which are junk. 1.72 intake valves 1.50 exhaust small ports and such.
The 3927185 call for 68-73 307,350 heads but they also call for 69 327 heads same size valves as mention above on the 307 heads. Your heads are your biggest restriction right now. Everything on your engine sounds like a nice matched street engine but your heads are killing you big time. At the crank your probably looking at maybe 275?
Swap your heads for double humps or Vortecs and your probably knocking on the door of around 320 to 330. A stock rebuild with a shift kit will hold your transmission up nice to atleast 400 hp. My dad and I used to drag race a 1964 Chevelle Malibu SS with a built up 350 bored 60 over running low 11's full interior car with a stock rebuilt transmission and a nice shift kit. transmission was a turbo 350
MPac said:
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With Vortec heads the flattops will be right around 10:1. Edelbrock Vortec EPS manifold and a 600 Holley would be a great combo with that cam. Should be decent mileage too. That's a 330hp/370 tq combo I bet.
If you're on a budget, try to scare up some decent heads at least, like a 441 or 882 casting
thanks alot ill definitley invest in some better heads soon since im not in a rush i can save up money and go for something good. any other tips would be greatly appreciated. and hah i didnt wanna buy desktop dyno or any dyno simulators just cause i knew i could get some good answers on here instead.
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