I really loved my old school GK C1M-308R. I went from the 140 cam to this in my LT-1 and it was noticeably stronger in the mid range. It was hard on the valvetrain though. It also barely had enough vacuum for the brakes but man what a rush at 3500. This was with stock heads and the dual plane manifold. 4:10 gears and the M-21.

Are your planning to leave the rest of the valve train stock? It seems like a good idea to update the rockers, maybe like these Comp Cam rollers. It wont keep me up at night without the O stamped originals on there.

The press in studs do create some anxiety though. They are original and cool but it seems worth the 'loss' to keep my original 302 in one piece. Am I worrying about nothing here??

I'm likely going with the Comp Cam 12-107-3 (3849346 replacement). My '69 has an M21 and 4.10 gears. Both of these have updated internals.

:wink:

I'm in the same boat with the car I have now. I was thinking about roller rockers but then it usually mushrooms into removing the heads, doing a set of screw in studs, guides and likely more when I get to that stage.

I'm not planning to buzz my stock 302 beyond 6500 when hammering it through a few gears, and it's not like I'll be doing it that often so I then relented to leaving the stock valve train alone. Just my 2 bits...and just so you know, that 12-107-3 cam choice makes "excellent" vacuum for the brakes. Mine are fantastic right down to 900 idle and brakes work awesome.

For the studs you can always do the old trick of pinning them. It's hard to see once done and keeps them from backing out.

The best running BBC's I've owned for the street, always had three things in common: 4:56-4:88 gears, high compression, and high performance GM cam (l-88 ZL1).
Can't say if it's the same for sbc, but I agree with Sam.

I'm a huge fan of the LT-1 cam. I've used it in a few different 327's. 11:1 and 9:1 pistons. Still makes good vacuum to run the brakes and easier to tune. I have one in a 62 F.I. Corvette right now and it runs HARD.

Hell, I'd put that cam in my garden tractor if I thought I could get it to fit!

Here is Tim's garden tractor come next summer...:3gears:

https://i.pinimg.com/originals/e4/6c...2e644c6c69.jpg

I have these 492 heads also but currently into the Day 1 thing. They do have screw in studs already though :) Would a cam choice here be any different or perhaps make the 140 happier?


Attachment 149498

I went with a Comp Cams grind selection that was based on my engine displacement, compression, and rear ratio. When done with modifications roller rockers , headers and bored 40 over, the engine put out 409hp @ 7050rpm and 373lb-ft of torque. It's a flat tappet cam. The modern dual pattern and aggressive ramp cam allow for both HP & Torque. I have the grind card and will send it to you. It has a nice lope but I could care less about the idle sound, the drivability & performance is what I care about.

It really depends on what your looking for. I purchased a 71 Z It was all original but indy cylinders heads built the engine, stroked it to 383 and used a Hydraulic :( XE 268H 224-230 110 cam. it had super strong low and midrange with 373 gears and the Four speed. but at 10.5 to 1 and California fuel. Boy did she rattle. So to bleed off cylinder pressure and get back to solid lifters. I installed the Nostalgia Pluss 12-673-4 247-254 112 .012Lash.. Best Sounding cam Ever.. Lost all its torque and dead on the top. And this was a 383.. I figured it would hate the stock exhaust.. But no more knocking.. I installed shorty headers and a low restriction transverse system. Now she had Killer mid and top end power.

When I was building my 69 Z engine I was planning on Dropping the compression to 10to1 and using this Comp XS 274S-10 236 242 110 .500 This would of made that little engine run much better than its high compression big cam factory setup. And been pump gas friendly, still sound great. But after tearing down the engine and seeing every factory part still there, I didn't have the heart to change it. and rebuilt it all original.