I tried to search , but zippo. What should ring gaps be on a .030 over 454 with a 671 blower ? Figured I'll go to the experts ! Thanks , Mike
Depends on your application. If you are looking for a hot street motor with a 6-71 go with the standard BBChevvie ring gaps. The blower won't make any diffrence. Remember, ring end gap might be specific to your piston manufaturer. Hyperutectic pistons have a different gap than a cast or forged as a general rule, but to be on the safe side ask the guys who make your piston. Tell us more about what you are building. -Abone.
By the way, 69Fury...Judging by your avitar, I don't know if you should be giving out engine advise... (just kidding, of course!!) -Abone.
Read a article that stated blown motors create more heat and ring gaps should be wider but didn't say how much. Its a forged GM crank ,**** rods speed pro forged 7.5 pistons , Mag , iron square port heads .Have'nt got a cam yet , looking at Comp 284 hyd roller. This is for my 48 Anglia g***er,sorry about the poor pic. Hope to have an update soon Thanks , Mike
lol!!! I'd be proud to be involved with that car! The Majic Muffler Toppolino driving over the pan and crank is epic! I've heard that the photo is covering one entire wall of the Peterson publication photo archives room. I want one that big, too.
Like he said, for a typical street motor you can run normal gaps. If you are running a lot of boost then you might want to open them up just a little bit, maybe .020 or so, but don't go crazy. Sounds like you're running blower pistons, which usually put the ring down a ways further than normal pistons.
Talk to a cam grinder about a specific grind for your engine/application. Don't use an off the shelf cam... my .02 cents.
On a mild street blown big block, a normal cam grind (such as the 284 comp cams) is gonna be very close to what they'd recommend for a blower motor. I think the one Comp recommended for me is this one: http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=453&sb=2 been a few years, but it sounds familiar. pretty much anything with a sort of wide lobe separation will do. A low lift cam like this lets you run mild springs and they and the valve job will last a long time
http://www.rlengines.com/tech/speedprorings.pdf I filed end gaps with a point file, towards the inside to not chip edge. Check it often as a couple extra strokes can put you .002 too big.
.004 per inch is what i used. so .016 or so . Mines a .040 over 454, w8:71@ 8psi.Forget cam specs but it's a crane hydro w/560? lift. real mellow but tons of power down low. supposed to be 700hp by specs of local dragboat builder.
Majic Muffler Toppolino Hell ya, This is standard minimum required information in hot rodding isn't it. It's a legend ! Gene
If you want to be safe, put .032 on the top ring. If you **** the ends, it will kill a cylinder instantly. There's alot of variables in this so I can tell you that this will work.
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