The Stovebolt Site Forums The Shop Area Engine Shop Looking for opinions on an engine build-up

Well, after a few years of neglect, the '65 is finally getting some much needed attention. The engine is out and the truck is undergoing re-wiring and bodywork. I am planning the engine build right now, and would like to run it past you for opinions.

The engine is a '68 307 with a '72 TH350 behind it. The truck is a '65 C20 with 4.11 gears and power brakes.

The engine is going to be bored and completely rebuilt this time around. I haven't decided yet if I will keep the 307 block and just rebuild that, or find a 350 block and make a 327 using my 307 crank, rods, and new 327 pistons. We covered this combination a few years ago on this forum. I don't really want a 350--too common for me and there is something special about a 327 I was running a set of '65 Power Pak heads with 1.94 intakes and whatever the stock exhaust valve size was (1.5 or 1.6 on these, I can't seem to remember off hand) and 58 cc chambers, these are in good shape and will be re-used, but I will go through them again to make sure they are up to snuff. I want this engine to make in the neighborhood of 9.5:1 compression when done and make about 300 hp or a little more would be good. I want to get good low-end torque, but I want a good strong mid-range too. Very top end doesn't concern me much.

I have a brand new Holley Street Dominator dual-plane intake with a new 600 cfm 4160 carb for this engine. I will also be installing block hugger headers on it. I know I will lose a little low end with these over a full-length header, but that is a sacrifice I am willing to make in the name of changing spark plugs

My main concern is camshaft selection. I want to have a little lope to the idle, but this will be an engine that would be pretty easy to put too much cam into as well it seems. I need enough vacuum for power brakes and distributor advance too. Also, I don't know any specs on the torque converter that is in it, but I have no problem replacing that with something compatible with my set-up. This will be a driver, not a race truck.

I am looking at a Crane single-pattern cam with 216 degrees duration at .050, and .454 lift. Would this possibly be a little too much, I think they also have one around 212 or 214 duration as well. There are also some dual-pattern with similar specs, what are the advantages/disadvantages?

Any opinions/advice? Thanks.

Aaron

The best thing to do IMO when one has a cam selection question is to present to the cam manufacturers the same info you offered to us. Crane (and Comp too) have online forms and they can offer the very best setup for what you are looking for. This is much better than reading some catalog and "point and shoot" selection.

www.cranecams.com

I've been building smallblock engines for several years, from mildly warmed-over to full race roundtrack engines. You're pretty much on the right track, except for the cam. I think your selection is a bit too radical, and will probably give it a little more lope than you expect. My "go-to" cam for a street performance engine has been the Comp Cams High Energy 260 for quite some time. While it doesn't quite have a lope, it sounds like a stock engine that needs a tune-up. Combined with a torque converter that has about a 1,800 RPM lockup speed, it will perform very well, and still be useable with power accessories, power steering, air conditioning, etc. The next step up in performance, and idle roughness is a 268 High Energy, which works best with a 2,000 RPM converter, and a larger-than-standard vacuum reservoir if you're using power brakes. Consider using a set of ram's-horn exhaust manifolds, unless you want the headers just for looks. They won't give any noticeable improvement in performance below about 4,000 RPM, and you'll get tired of burned-out gaskets and plug wires awfully soon!
Jerry

Look at the Compcam XE262. I agree, call the cam manufacturers and talk with their tech. The can do far better than any of us.

One change I would make is to go with rams horn exhaust manifolds instead of headers. Performance is almost as good, better if you can locate a set off a vette with 2.5" outlets. And you don't have the plug or heat problems.

Thanks for the help guys. I'll see what the cam manufacturers come up with.

I just finished tearing down the rest of the engine yesterday. I don't see any surprises yet. Now I just need to talk to the machine shop about what I want to do. I'm leaning towards just staying with the 307 right now, as long as they don't find any problems with my block.

Speaking of machine shops, since we haven't had very good luck with the local guys, I am planning on going somewhere else. I often see an ad in the local paper for Autohaus Engine Rebuilding located in Shawano, Wisconsin. They claim to specialize in classic and performance building. I will definitely be contacting them to go over this. Anybody have any experience with them?

Does anyone know of some other shops in the northern Wisconsin/Michigan area that I should try? Thanks.

Aaron