Got another question for you all Is there any way you can fit sbc cal custom finned valve covers staggered bolt holes on straight bolt holes heads off a 1970 307 cause thats what i got and its a hardcore budget project
I'm sure you could fabricate some sort of adapter like they sell to mount old school SBC covers on center bolt heads. Might be a bitch to do, but it could be done.
A guy could probably modify a pair of those adapters to work with the early covers. You would have to cut out the webs for the center bolts. drill out and counter sink two of the holes for the straight across covers ( to use a counter sunk machine screw) and drill and tap two holes for studs for the offset covers you would probably have to drill out the other holes in the opposite side rails to allow the bolts or studs to go through both the covers and adapter and both gaskets. To me it looks like a leak hunting for a place to happen but it would get the job done.
sell the staggered ones and get new ones that fit. Obviously with a 307 you are not concerned with "perfect" period correct bs. $140 link
Could you just braze a couple nuts in the correct place on the head and screw into them or even use studs?
Why not pick up set of damaged/cheap straight bolt valve covers and cut the flange off the bottom, drill and tap to fit and use these for adaptors?
Ditto. Why make yourself crazy trying to adapt those, further delaying your project, and they still won't fit.
Sell 'em. Staggered bolt covers seem to bring big bucks on evil-bay. Should get more than enough to buy what you neeed.
The old staggered Vette covers are everywhere and the straight ones are a little expensive. I have seen the staggered ones on the later heads but it was either an expensive fix or a butchered up bad job. The expensive fix consisted of a set of valve cover spacers. The ones that you can use if you are running roller rockers. They were made into adapters by some welding and re drilling etc. That requires someone that can weld aluminum and some machine work. Sorry there is no easy way.
Kinda pricey, but I just found these on Ebay. Maybe you could just get ideas from these and make your own. Or, like the other guys said, just sell them and buy the right covers... http://cgi.ebay.com/ebaymotors/55-89-Chevy-327-350-Valve-Cover-Spacers-+-Adapters-_W0QQitemZ160314830450QQcmdZViewItem .
I have a similar issue, I have a set of canadian "pontiac" sbc valve covers that I want to put on a 350 that is in my OT TA. they are stamped steel. Would a set of those spacers that they sell for highlift valvetrains work?
Years ago in one of the car mags they showed how to do this easy. Just drill & carefully tap the heads to match the staggered cover pattern and epoxy the studs in. If yer careful, no one will know. Have to be careful because there isn't enough meat there to drill a good hole (only catch 2 sides), that's where the epoxy comes in. Boom, done.
Oops, I somehow missed the Low buck part when I posted. In that case I think I'd have to sell or .trade the ones I had to get some that bolted on. The other option if you need to rebuild the engine or it needs a valve job anyhow is to get a set of early powerpack heads with the staggered bolt pattern and have those redone. The 307 tends to like the power pack heads especially with a mid/late 70's Z28 cam. I think I'd look at Pastlane's suggestion. Maybe even build up the inside rail with epoxy or jb weld first then drill and tap. It would have to be super clean though.
I think low tech installation with studs would work, but would require some kludging to seal. It's been a while since I've looked at iron lopo Chevy heads, but the ridge that seals to gasket is very inadequate. I think you would have to build up the ridge including the old bolt hole a little. Hole could be filled with a cutoff bolt filed to suit, and then area built up with some kind of Devcon...welding seems off the dollar and difficulty scale here. Part of the war against leaks then could be a really good steel core/silicon gasket, carefully notched to clear new hole, glued in place. These heads are hard to seal stock, and I think will require some Mickey Mousing something like the above to keep the oil on the inside if modified.
thanks for all the suggestions guys really helped me out , sorry about the hardcore delay on replying but very rare i am on the computer and family member was very sick for a while but i still have not decided what to do yet i posted the valve covers up for trade or sale but guess no one was down so heres a pick of the covers want the same style finns and cover, do the straight hole covers have the same style cause thats what i want the most these look the best i even polished them and painted them
These ones puzzled me: the 'staggered' holes do not look in line with the 'straight' ones, and I'm sure the pile of spare SBC valve cover gaskets I moved the other day had the two sets of holes together?
I built a set of adapter plates for the '32 in my avatar a while back out of 1/4" X 1/2" steel strap. I used countersunk screws to hold the oddly spaced side of the plate to the head and used studs (welded from the bottom of the plate) to mount the valve cover to the adapter. The normally spaced side just gets the studs from the head thru the adapter and the valve cover. You then use a gasket on each side of the adapter and there you are. It took a couple of tries to get them to seal due to slight warpage from welding the strap together into a rectangle, but they have been on my truck for almost 13 years with good results. They arent that noticible if you trim away the excess gasket material. Why did I do it? I was given a beautiful set of early Edelbrock staggered bolt valve covers and was trying to build a "period" piece on a tight budget. Would I do it again? Probably not, but if I did I might try milling them out of plate instead of welding them together to keep them flat. On the up side, I do see a lot of people scratch their heads wondering if early camel hump heads ever came with the staggered valve cover bolt pattern? I do enjoy going that extra mile to make people think!
find someone with a waterjet and have them make you a spacer using an early gasket. drill holes for taperhead screws.....
Lets clarify........as I'm possibly confused.......are you saying you have staggered bolt holes on the heads or on the valve covers? I thought your question was do the straight across valve covers by Cal Custom look the same.......mine are straight across holes (heads and valve covers) on a late 70's 400 cui sbc.......
The Jalopy Journal
