Some of Comp's basic cam grinds. Comp STILL doesn't have many Nailhead listings, but the same grinds are offered for different engine families.... These were listed for AMC's which have the same 1.6 rocker ratio as our Nailheads. Old's uses 1.6 ratio as well. Comp can put these grinds on one of their Nailhead cam cores. Their entry-level 'High Energy' series offers a improved lobe design with near-stock duration and lift specs..... The '260H' grind has 212 degrees duration, 0.447" lift and 110 degree lobe separation. It's a close match to Buick's dual quad, 'Super Wildcat' cam (you listening Doc??) Stock Buick cam specs are: 209 degrees duration. 0.439/0.441" lift and 109 degree lobe separation.
Next step up is their 'Extreme Energy' series. (These are Olds listings) The XE 250H, XE256H, XE262H should fit without valve-piston clearance issues. The XE268H gets tighter, but may fit with thick head gaskets. I like the XE274H grind....it's comparable to TA's 413-401 grind, but with more low -end. I want to test some hybrid cams, like a 218-230, 224-236, or even a 230-240 design on the 'Dyno 2003' software.....most of the Comp cams are already in the camfiles, so you can pull the exact specs from the program files!:grin:
Unfortunately no one lists what the ramp rise is per degree of camshaft rotation. Performance can be TOTALLY different with slower rising ramp speeds given ALL other specs are close or close to the same. I don't understand why ALL manufacturers leave out this vital piece of info out or unlisted.
Comp also has a master Lobe Catalog online! In it, you'll find 'duration @ 0.200" lobe lift' specs. With those numbers, you can get some idea if it's a slow-ramp, or fast-ramp design. Another useful spec is the 'lift @ TDC'....it'll give you some idea of v-p clearance. CompCams has the most info online I've seen so far.:TU:
Walt, I found another Comp catalog, it even has the Thumpr data listed. I'm trying to upload it but it won't let me. Want me to email it you? Not sure if it's the same catalog you already have. PM me your email address if you want. Also, not too sure how much you've played around with Dyno 2003, but the program will calculate the lifter acceleration rate if you plug in all the cam data (the advertised, @ .050, and valve lift specs). The XFI lobes I refered to earlier had a pretty stout ramp rate compared to a lot of the other cams we've been talking about.
You can get just about ANY lobe listed for any motor for the nailhead but why did you add the thing about wide lobe spacing and lift? First it is duration that causes PTV Issues(not lift) so if anyone does get cams and stays with stock pistons get the PTV measurement and list it so fellow members know what will work. Guys adding cams without the full build are asking for trouble and a full build soon down the road. Get NOTCHED pistons Then consider the heads. If you cannot afford the better valve train/porting remember tnat the cam can help coverup some of the valve/flow issues. Cams are only a small part and Comp can do about anything you want but just make it easy and stay with the XFI/EX-TREME ENERGY lobes. Tony PS: by the way, if the Buick guys actually bought some parts they might be listed but bench racing does not get the engine in the catalogs or magazines. No offence intended but Tom is in the 10's but nobody sends that to a magazine? Why not? Look at that 322" article, not much there but considering the magazine it is comparable. Heck, highlight the entire forum, 'Da nailhead. Show that the motor can be a go fast without being like every other chevy. Show the race car type like TT's, the steret type of GSGTX, the showcar of________________________-you guys know some of the rest, fill them in and contact the primo mags! Imagine a 600+HP turbo 425!
