Thread: right combo?

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Looks like a horrendous mis-match of parts to me.

First off, the heads are stock replacement heads that will flow about the same as any Chevy cast iron production head, just over 200 CFM at 0.400" valve lift, so they will not support the grind of camshaft or intake manifold or torque converter that you intend to use. Those little 170cc intake runners will be all done and gasping for air at the converter stall point, just as the motor is "gettin' up on the cam" and just as the intake manifold is beginning to flow some decent numbers. You didn't post the volume of the combustion chambers, it could be 58cc's or 67cc's or 76cc's, so I can't figure the static compression ratio for you to match up a cam grind. The carb is too small to make any serious hp, although you may save this combo with the planned nitrous. I don't know, I never used nitrous. I'm suspecting that the "roller rockers" you refer to are actually CompCams Magnums, possibly the worst rocker you could have chosen because of the sliding ball fulcrum. I've seen 'em generate so much friction that they turn the entire rocker body blue from the heat. If you're going to invest money in "roller rockers", then invest in a serious rocker that utilizes a roller bearing at the fulcrum, such as Scorpion.
http://www.summitracing.com/parts/scc-scp1000/overview/

The Victor Jr will only make things worse, it was designed to make power from 3500 to 8000 with a strong set of heads and a minimum of 750 CFM.

I don't mean to be condescending to you at all, but it appears that you haven't a clue. First and foremost, the heads are junk for what you're trying to do with 'em. Sling 'em over the fence and invest in a set of Pro-Filer aluminum 195cc intake runner heads that'll flow 260+ out of the box and build from there. You're trying to build a serious RPM motor and the heads you have just simply will not work for that combo.
SBC 23 Degree Cylinder Heads
You can have a set of these heads, fully assembled and ready to bolt on, delivered to your door for under $1100.

The cam that's in it now....
Elgin Industries : Online Catalog

The cam that you're planning to use.....
http://www.summitracing.com/parts/sum-1107/overview/

The World website....
http://www.pbm-erson.com/UserFiles/D...g-Download.pdf

Here's a tutorial that I wrote on another forum that will explain what cam timing to use with what static compression ratio.
http://www.crankshaftcoalition.com/w..._compatibility

The other thing to consider is that current pump gas quality limits iron heads to about 9.5:1 static compression ratio. Cylinder pressures generated by higher static compression ratios can result in detonation. Aluminum heads will support 10.5:1 on current fuel quality.

And finally, you didn't share any details about the headers with us, but what I would use with a high-revving small block with N2O would be 1 3/4" x 30" equal-length primaries with minimum 3/8" flange thickness. Thinner flanges will curl up from the heat and spit out the gaskets.

You other fellows reading this would do well to begin with a proven combination of parts as published by one of the leading automotive magazines such as Car Craft, Hot Rod, Rod and Custom, Chevy Hi-Performance, Street Rodder or other popular magazine.

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