-- 1970 4 bolt 350 block .030 over
-- 3973370 64cc heads 1.94/1.50 (all ports and casting flashes smoothed out by me)
-- Speed pro .100 dome hyper pistons (P/N H618P)
-- Felpro .041 head gaskets
-- New Eagle cast crankshaft (good for 500hp they say)
-- Quadrajet (well tuned)
-- Performer intake
-- 1 5/8" Flowtech full length headers, 2.25 pipes through Summit turbo mufflers. No H-pipe.
-- GM factory grind 350/350hp cam
-- HEI ignition (Pertronix flame thrower coil)
-- Elec fan. Serpentine belt P/S, W/P and alt.
-- Tranny is a TH350/2000 stall, 3.08 rear gears

There may also be plans for a 100-150 NO2 shot in the future.

I guess what I'm asking is if there a better cam for this 90% street driven Chevelle? I'm changing the lifters, so I might as well change the cam while I'm in there.

TIA for any comments you have to offer.

Your CR is approximatly 10.34 with a .066" quench. If you get the quench down to .040" the CR goes to 11.1. I suggest you use a flat top piston unless the domes are already installed. With a flat top the CR is 10.27 with a .040" quench. A .035-.045" quench is very advantageous. There are a lot of cam that will work well with pump gas and 10.2-10.3 CR. An 11.1 CR will require a pretty big cam for pump gas. If you have and want to use the dome pistons, you'll either have to run a very wide quench or run a big cam (which will not like your gears and need a high stall canverter). I don't know the 350/350 cam specs. I know a lot of performance builders are not fond of it.

I like everything except your cam choice. The old factory cams are hopelessly outdated compared to modern aftermarket grinds.

Thanks for the replies...I don't like that cam either. It just doesn't work as well as the newer ones. I already have everything in the list, except new valves, and the rings.

I'm looking for a cam that will keep the duration low for lower rpm power range, but still be workable with the CR. (Running on 92 octane would be nice also.)

I have no objections to going with 1.6 rocker ratio (I can trade in the new Crane 1.5's with no issues), what I'm thinking here is that I need more lift to make this combo to work properly. :confused:

If this is a way around it, that'd be a nice easy fix.

Cams are a little tricky, I'd like to hear advice from people who have more experience than myself when it comes to cam "Magic"

Am I way off track here? :confused:

Don, take a look at the DCR page linked in my sig. Some useful information on matching cam to compression. It usually takes an increase in duration to bleed off a high CR. Can you return the pistons for flat tops?

Don't know what it would cost, but a competent machinist could mill the domes off of your pistons. My uncle had that done on a factory LT1 shortblock years ago because the class rules he was racing under required flattop pistons. It worked fine.

Thanks for all the help guys!

I've taken a new direction with this one.

I'm sending the domes back in for flat-tops. Just too much trouble making this work properly.

This way I can work with a cam that will work with the CR.

Take the combo above, change the pistons to flats.

-- Daily driver in the summer
-- Weekend strip runs.
-- Rpm range target starting at about 2000, never reved over 6000.

Any thoughts on the best make and PN cam for me?

With your combination of parts;
2000 Stall,308 gear,Performer intake,and 10.2 compression I would go with something like

Crane Energizer 272H10
216 272 454 110

The cam and lifter kit is PT#100052

$99 From Summit http://store.summitracing.com/

With a 10.2 compression you could go a bit longer with the .050 duration,something like 222-225.
However I can't help but think that with the weight of the Chevelle combined with the 3.08 gear you will be happier with the milder 216 .050 duration.

Thanks for the replies, I'm sending the domes back for flats on Monday.

You guys really helped me out. graemlins/thumbsup.gif graemlins/thumbsup.gif

I have your same motor in my Nova. I have a comp cams xtreme energy 268 and I love it. I'm running mid 13's on street tires and 3.42 gears and the same stall. Engine pulls good from 2500-5800rpm. I think it's your gears that are killing you. If you still want good street gears and average strip gears, 3.42's are the way to go. I'm at about 2800rpm @ 75 with 26.5in tires. You chevelle guys can run taller tires than a Nova. I'd go with the 3.42 gears and 275/60/15 tires. You'll still get decent gas milage and with the 268, and enough torque to get you moving at the track.

I have your same motor in my Nova. I have a comp cams xtreme energy 268 and I love it. Funny you should post that...before I checked in here, I had just finished running some numbers and used the 268H cam for a comparison. (I was looking for a 216*/218* cam like thrasher posted)

It seems like it would work well with the setup I have.

EDIT: I just realized you said Xtreme Energy 268. I was using the High Energy 268. There is quite a difference in the cams.

I'll have to run the numbers again to see what I come up with.

Thanks a lot for the "real world" info on how that cam is working for you. graemlins/thumbsup.gif

I only suggested the 272 because it will bleed off just a touch of cylinder pressure compared to the 268.