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Discussion Starter #1
Hi everyone, I have my 68' 302 block at the machinist with the stroker kit and that will be done within a week, but funds are low I was wondering would it be feasible to run stock heads with a stock cam and a 600CFM carb in the mean time while i save up for AFR 185's and a new cam?
 

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Shouldn't be a problem, considering what you're basically gonna have is a slightly de-stroked 351W, and they run fine with stock heads, cam and a 600 vac sec carb... Just make sure your heads have the proper combustion size for your new pistons. With a stock cam and heads, you shouldn't have any PTV clearance issues.
 

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do your research get your cam now! you will be happy you did
 

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Like jk69cat said, get the cam now and install it if at all possible. If not, you'll end up cussing yourself when you have to pull the radiator, front accessories, water pump, timing chain and cover etc. to get the cam out once the engine is in. Chances are a cam is going to run you $100-250 depending on the grind and how thrifty you are. Then, later you can install the heads, which isn't exactly pleasant while the engine is installed, although is only a single day job (1/2 day on carb'd cars) and doesn't require full removal of everything like a cam does.
 

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^^^ what they said ^^^ re: am now

Better to wait a bit and do it right the first time vs throwing more $$$ at it later (and redoing much of the work you did...)

IF you can swing it, go with an aftermarket retrofit hydraulic roller cam setup. You'll be glad you did for a number of reasons.

1. No worries about camshaft wiping out during break-in.
2. No worries about camshaft premature failure due to today's lower ZDDP oils. Flat tappet cams need that additive package to survive!
3. Less rotating friction = less wasted power
4. Better cam profiles for more power in the first place!
5. Did I mention MORE POWER???

When I had initially built my 9.5:1 393W stroker, I used a Comp Cams X4262H hydraulic flat tappet cam and 1.7:1 rockers to give me a relatively high lift/short duration cam for emissions compliance reasons. I later switched to a retrofit hydraulic roller cam Comp Cams XR276RF-HR with the same lift and gained an instant 80+ horsepower with no other engine changes! Oh, and it still passed Ohio's emissions sniffer test!

Based on that experience, I'll never use another flat tappet cam in any of my engine rebuilds!
 

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Discussion Starter #6
Thanks for the advice, you all rock!

Since im moving soon and buying a bike the project will be put on hold. However since the car was cursed with the "vinyl top of death" I decided to save up and get all of the body work, new roof install, done while i save to build the engine. that way when the car comes together it will be done, probably not but here's hopping.

My cam choice came down to one question: do I want 10 miles per gallon or 4?

The cam im going with is a hydraulic with around a 282° duration and AFR 205cc heads with a 750CFM Holley double pumper overall CR should be around 10.4-10.8:1
 

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AFR 205s will be overkill for a 331-inch motor unless you plan to rev it well over 7000rpm. Likewise the 750DP. 600 or 650 would be a much better choice. Vacuum secondary if mostly street.

BTW, with my 393W with that aforementioned XR-276RF-HR cam, a 3200 converter and 3.55 rear gears, I'm still getting 14-15mpg. Of course with an AOD automatic!

BTW, I tried a 750DP on my 393 and it stumbled and bogged terribly off the line, with no better power at top end. Just too much fuel at low rpms - more than the engine could handle. I also tried a old OEM 3310 780 vac sec Holley and the lower rpm throttle response went away with no increase in power. Same ET/MPH. The 670 Holley Street avenger works perfectly for my motor.
 
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