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Old 01-02-2013, 06:06 PM
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Originally Posted by Rmatt87 View Post
Hey HotRodders,
I was on here earlier looking up how to build the cheap made in mexico 350 V8 and seen how big the gain in horsepower was with the ported Vortec heads, intake, and Holley carb. I realized that i have a Vortec engine thats in great shape so ive decided to build this block for my S10 V8 conversion. I was wanting to know if anyone can give me an estimate in horsepower if i use a Big Mutha Thumpr Cam from COMP Cams, ported Vortec heads, big long tube headers, Flowmaster 44 mufflers, Edelbrock Performer RPM intake manifold (Dual-plane, High rise), and a 750 CFM Edelbrock Performer Carb (calibrated for performance). The camshaft has an RPM range of 2600 to 6800 and the valve lash is listed below:

Intake Exhaust

Duration 291 311

Duration@.050" Lift 235 249

Valve Lift 0.573 0.558

Lobe Lift 0.338 0.329

I will be using the recommended kit from COMP Cams and the compression ratio recommendation of 9.5:1. I haven't decided on the type of ignition system as far as the distributor goes so if anyone has any suggestions that may work with this application feel free to let me know. I apologize for writing so much for the first time.

What year v8 is it you mean genII? I think gen III is LS motor.

Also note it says atleast 9.5:1 you may want to hit a little more cr with that cam. You may also want to think about the smaller one unless you are going for some big power. Have you checked the drc with the bmt. Ots very low with less than 11:1 compression. Intake closes at 71 degrees @ .06" so its a big cam and will act like one. Not that i am agaist it got one my self going into my next build but i am realizing its going to have a dcr in the low 7:1 area. So i had to make some changes in my build to hit a much higher compression number. It will surely run at 9.5:1 but if you want it to really pop off you may need some more cr.

What type of heads are you running. Bmt is a big breather crappy heads even ported will not flow enough. Unless you have the good vortech castings you may not get the results you want. Cam is peaky if heads are low rpm they will miss each other. If your going to run the bmt you at least want the big end punch. I think there is only one vortec head that is any good comes in two casting numbers 906 i am not sure of the other. There is also a bowtie head that is very good.
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