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-   -   max lift on stock BBC heads (http://www.chevelles.com/forums/showthread.php?t=158228)

SoCalRat Jan 7th, 07 2:53 AM

max lift on stock BBC heads
 
What is the maximum lift that can be safely obtained using the 063 heads?
Seems .600 is what I recall but the flow numbers posted in Car Crafts head data section lists flow to .750

Junkyard Dawg Jan 7th, 07 8:26 AM

Re: max lift on stock BBC heads
 
I've asked this question before and have been told to just have the heads checked....

mr 4 speed Jan 7th, 07 8:30 AM

Re: max lift on stock BBC heads
 
I have used the GM L88 cam and long slot rockers with stock closed chamber heads before.
Lift was .540/.560

92Camaro Jan 7th, 07 3:39 PM

Re: max lift on stock BBC heads
 
If the heads are apart then this will be easy to measure. With the seal on the guide, valve's installed both intake/exhaust, keeper's and a retainer. Measure the bottom of the retainer (near the lock part of the retainer) to the top of the valve seal using a dial caliper. Get you're number then subtract .060 form that number and that will be the total lift.

Ron Miller 92Camaro:beers:

SWHEATON Jan 7th, 07 5:01 PM

Re: max lift on stock BBC heads
 
Dont forget that max lift also has a very important componant to that mix which is piston to valve clearance.

063 heads may in fact be able to handle .600 lift but maybe not if the heads & block are decked,if using high comp/high domed pistons,and a long duartion large overlap high perf cam so keep that in mind too.

Scott

Bob West Jan 7th, 07 5:38 PM

Re: max lift on stock BBC heads
 
I think Ed is over .700 lift with his 215's. I guess it all depends on how much work is done to them.

Pro67Chevy Jan 7th, 07 9:05 PM

Re: max lift on stock BBC heads
 
This is only the 4th engine I've put together so I'm no expert but, if you ask me, valve lift goes far beyond just what head you are using. That is just the beginning.
What pistons are you using? What kind of reliefs? What size valves? How much cam duration? What springs are you using? What's the installed height? What kind of head gasket?

I'm also using the 215s and if I'm not mistaken the 063s are the same closed chamber design. I have 2.19" valves and i'm using a .647" lift SR and I have plenty of room with TRW # 2399 small dome pistons and decent reliefs.

SoCalRat Jan 8th, 07 12:56 AM

Re: max lift on stock BBC heads
 
Thanks for all the replies, Looking at the Voodoo 60212 roller. Pocket ported stock heads with stock valves for now.

Looking at the same piston. Currently using the .022 steel shm but can change to meet the need. Want 9.5 -10.0 on the compression

Mike Feudo Jan 8th, 07 11:11 AM

Re: max lift on stock BBC heads
 
I have never raced with an oval port head but the big port closed chamber heads really don't gain alot much over .650 lift because of the shrouding of the chamber wall. Is there is reason you want to use the most lift you can? It will cause you many maintenance problems that can be a real pain.

SoCalRat Jan 8th, 07 5:40 PM

Re: max lift on stock BBC heads
 
Mike, The roller cam I was considering has lift of .619 so I needed to see of the heads would work or if I should go to a smaller lift cam

cstraub Jan 8th, 07 6:24 PM

Re: max lift on stock BBC heads
 
Bottom of the retainer to the top of the guide including the seal. This measurement is your max cam lift possible. The measurement will also very on every engine because of guides, retainers, seals used.

Measure this area and you will know for sure.

Pro67Chevy Jan 8th, 07 10:04 PM

Re: max lift on stock BBC heads
 
Garry,

Maybe you could post a subject:Voodoo 60212.

With reguard to springs, keep in mind...

1) Regardless of the lift your current springs yield, piston-to-valve clearance will ultimately decide what lift/duration you can get away with.

2) Your new cam will be matched up with a new set of springs that you should be using. This will ensure you have the proper lift requirements and spring pressure.

Jim


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