You guessed it...I need a cam recommendation from you. Here's what I've got. 388" smallblock, 10.3 compression, pro-topline 200cc iron heads, 750 vac sec carb, 1 3/4" full length headers, 2 1/2" exhaust, 3500 stall ATI convertor, 3.73 posi, approx. 26" tall rear tires, all in an approx. 3500 pound '77 nova. I was running a weiand 7530 single plane intake (similar to a vic jr.), but will be switching to a holley 300-36 dual plane. I was running a comp 294s solid, and was pretty happy with it, but since I had to go thru the engine again, I am looking for something even stronger...especially in the 3000-6000 rpm range. Looking at shifting under 6500 rpms. Idle quality isn't too important, but I do have power brakes (but I love a lumpy idle). Looking for a solid flat tappet.

Also, I just installed a comp cams 260ah-8 in my 8.2-1 compression 355 and dropped it into my 3/4 ton truck. Did you design this cam? It was one of the "other grinds" in the back of the catalog. It is 212/218@.050, .444/.444 lift, on a 108 lsa. I have run the 260H and 268H high energy cams in a bunch of other vehicles, and this cam does not sound the same...it really barks when you step on the gas.

Thanks!

Travis,

Sorry to jump in on your post but I have a question about your truck / cam combo.

I am in the process of planning a motor rebuild for my C20 84 Suburban.

I have a 400 SB that I plan on rebuilding and was wondering about the cam you are using. I am looking for maximun grunt down low and won't take it any higher than 4500 rpms. I was looking at something similar to what you are using (maybe a little smaller) and was curious about the driveablity of the 260ah-8.
What is the idle like? What about low speed (less than 2000 rpm) operation? I was thinking about the 252ah-8 (206/212 @.050") but was concerned with the 108 lobe separation and low speed driving.
My Suburban has the 700R4 and 3.73 gears. During most normal driving, the rpms rarely goes above 2000rpms. I would like to try a 108 lobe sep, but I don't know if this would be a good idea with the fact of my LOW rpm operation most of the time.

Thanks in advance.

is it just me or did every one miss the post by harold explaining that he was busy with some project at his work and recomended calling lunati and talking to one of his guys that used to be with ultradyne or calling him directly.

Harold said he would not hear the phone ring, so dont call him at work....ask for one of his guys if you want cam help or to order...he left his regular email address and said he would check it twice a day, and try to respond when he could. He made no mention of not asking questions here.

Hear tell at those slight 200+ durations 108 is fine. Maybe 69LS1 ( Al ) or someone who has used/installed a very short 108 cam can chime in. If it was slow to build torque below 1800 ( which I can't imagine), you could always bring in the carbs enrichment circuit in early or the timing curve in quick right there and cover it.

Darren, I haven't put many miles on this thing yet as I just fired it up and broke it in 3 days ago. I haven't finished fine tuning the idle but as it sits, it pulls 15" vac ad 600 rpms...I know I can get at least 2" more out of it. I installed the cam 4* advanced on a 104 icl. This engine came out of my nova when I bought it. It was a low mileage rebuilt 4 bolt 350 with a lot of good parts, but it has cast rebuilder type flat tops at a whopping .051-.053 in the hole. With my .041 heads gaskets, I have no quench whatsoever. It pulls good right off idle, but really sings in the 2000-4000 rpms range. I probably have too big of an exhaust system too (1 5/8" headers and 2 1/2" duals with turbo mufflers) but I had originally planned on dropping a 400sbc in there. The truck has a beefed 700r4 and 3.23 gears, and pretty tall 265/85-16.5's on it. Once I get it tuned in, I'll let you know more. I originally bought it to use in the 8.5-1 400...I think it would work great especially with your 3.73's.

Travis G,

For a solid lifter to work power brakes in a 388 SBC, about as big as I would go is a Lunati 40199 (this means it is a Small Block Chevy custom grind) grind # 01-UF18-UF01-10-A01. This is 280/288 at .020, 247/255 at .050, 159/167 at .200, .525/.540 valve lift, and 110 LSA. A wider LSA would give a little more vacuum, but mild it down some. My 280 is about the same, only unsymmetrically, at .020 and .050 as the 294S, but it is 6° fatter at .200. It makes more power across the board than the 294S, and the 288F exhaust will pick up the power over 3500...
I did not design the 260AH, it's one of McWhirter's, I believe.
However, any cam with 50° or less of overlap generally gives OK vacuum signals. This is my figures, at .0045". A cam figured at .006" would have a smaller number. A single-pattern 266 should give about 50° on a 108 LSA, and anything smaller will have less overlap, and more vacuum.

UDHarold

Thanks Travis. smile.gif