The Stovebolt Site Forums The Shop Area Engine Shop clifford cams for 292

Hey guys, any one of you running the clifford 264 cam in your 292's? the specs are .518 lift, [email protected] and 110* lobe sep. I was thinking something with a bit more duration maybe in the 212-218 range for a bit more top end? its going in my 53' panel with a T5, 3:73 diff and 28" tires?

oh yeah and an offy 4bbl,holley 390 and Langdon headers.

What are you prepared to sacrifice?

I hope he's prepared to sacrifice a head if I pooch it while proving out CNC toolpath for bolt boss removal,lump prep/port surfacing(from T.Lowe), NPT threadmilling, and port floor spotfacing . The head's already in my hands so next gen experimentation is underway. Gonna hafta have at least a limited amount of street manners I guess.

come on Curt, I've got more confidence in you than that!!!....sacrifice?, not really sure, I can tell you what I'm hoping for, not concerned about fuel milage(its an old truck, they are supposed to be thirsty)just wanting a nice "sweet spot" that will perform well with my drivetrain selection,good low to mid range TQ, and HP to about 4500 revs.is that out of the question? HP of 250-275 range would keep me smiling.

Just my guess? 275 @ 4,500 is 320 ft/lbs., should be possible.

First pick up this book by Leo Santucci!
http://www.ebay.com/itm/NEW-Chevrol...k&hash=item53feb1f080#ht_2271wt_1193

yes, got the book. its a great read with a good amount of info,helped me make some decisions, now I just need to refine them.

I got Leo's book with the head a couple weeks ago and have been studying both closely. The pattern machine shown removing bolt bosses in the book is about as high tech as an 8 track player in as far as machine and cutting tool technology have advanced since then. So far I think some custom extended length NPT plugs that allow for port roof blending after being torqued with a hex head/washer flange to mimic the original head bolt may be in order.

That profile machine your referring used by Sissell Automotive is used to only rough the profile of the lumps once they have been brazed into the head, the bolt bosses have already been removed at that point so the brass can be fully installed and covers the entire intake port floor. For using bolt-in lumps, the process is even simpler. The bolt bosses can be removed by a much simpler method, a Bridgeport can be handy and usually by drilling through the bolt bosses from the top down to a depth equal to where the new bolt seating surface will be with a drill bit the same size as the tap drill for the pipe plugs. This makes the bosses paper thin and they can be easily knocked out of the casting with a hammer, and the new bolt seat surface can be spot faced. Tom Lowe even uses a sawzall to remove his bolt bosses. CNC is nice, I use one too all day, but many times they add a cost and complexity factor to things that can simply be done better by other means. I know your just playing and this is likely the only head you'll ever do, but I wouldn't consider devoting the time to remove the bosses in this manner, and I do quite a few of these heads myself. IMHO

Hey Scott, been a while since we chatted or I had any playtime with this stuff. No doubt what I'm going to do is possible with more primitive methods but I'm in it simply for the experience so cost or complexity are not factors in this case. Got any input on the port roof? It looks like the casting is thicker than a standard NPT plug so I would assume the usual method is to slightly overtap it so the plug comes flush on the inside? Sharing your experience on this topic is appreciated.

Hey Curt, the port roof does present some challenges for sure. Its also slanted as well as being thin. I usually just tap it deep enough so the plug can get a few threads of engagement and you don't have to get it too tight to seal up either. Then I mark each plug and dedicate them to their respective locations, tighten them up and blend them to the roof contour with a grinder. That way when you tighten them for real, they don't protrude awkwardly into the port and upset the airflow too much. Sounds like a cool project, but yours always are. Look forward to see how it turns out.

Well it looks like ill be going with the turbo cam from tlowe, I ordered a bunch of head stuff from him as well so hopefully my selections all work well together. Should have some goodies in the next few weeks.