Engine HP question
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Joined: Jul 2004
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From: Charlotte North Carolina
Engine HP question
Years ago I blew the bottom on my 79 L-82, I purchased a short block from Jaspers and re-installed the original 2.02/1.60 heads, intake, carb and manifold. The blown original motor was .30 over and was no turtle. The new engine just is not as strong even with the larger bore. I'm guessing it's the cam that Jaspers installed. I would like to pep up the hp on a budget and retain the stock appearance.
This is what I know about the short block I have:
350 4 bolt
.40 over
Flat piston
500 +-miles
Unknown cam
Runs great w/no smoke
I would like to:
Reinstall the original L-82 cam
New heads or rework exsisting
re-use manifold and carb
Add 60's style 2-1/2" manifolds w/matching exhaust
My questions are:
1)Is the L-82 cam worth reinstalling?
2)Can I do any tricks with gaskets/porting with these smog heads?
3)What are a good set of heads (besides AFR $$) with accessory holes to add with that cam?
The AFRs and Comp Cam are what I like but, I'm also budgeting for the 200r4 swap.
Thanks in advance.
This is what I know about the short block I have:
350 4 bolt
.40 over
Flat piston
500 +-miles
Unknown cam
Runs great w/no smoke
I would like to:
Reinstall the original L-82 cam
New heads or rework exsisting
re-use manifold and carb
Add 60's style 2-1/2" manifolds w/matching exhaust
My questions are:
1)Is the L-82 cam worth reinstalling?
2)Can I do any tricks with gaskets/porting with these smog heads?
3)What are a good set of heads (besides AFR $$) with accessory holes to add with that cam?
The AFRs and Comp Cam are what I like but, I'm also budgeting for the 200r4 swap.
Thanks in advance.
Instructor
Joined: Mar 2010
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From: lafayette indiana
dont reuse old cam not worth taking a chance with it for the price of a new one go to comps web site and u can download their cam program for free its easy to use and fun to play with. afr heads are good ones and i have had real good luck with rhs cast heads in our pulling truck big blocks(800+ hsp)
Team Owner
Joined: Jan 2006
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From: Crossville TN
If you change the heads, select the cam which will best match with the new heads. Don't go the L82 cam route and just add different heads. If you decide to keep the existing heads, then getting a new L82 [grind] cam would work.
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From: Charlotte North Carolina
Thanks, I'm going to the Auto Fair this weekend in Charlotte and will be looking around for some good heads etc..If I find something. I'm sure I'll post it, for some thoughts.
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Your pistons are likely a little lower in the block than stock due to *rebuilder* type pistons. That will kill some compression. If your heads have 76cc you're not even at 9.0 with the flat tops....you're down in the 8.7 or so range on compression.
If you change heads I'd go for some 64cc chambers. That will get you up in high 9's...close to 10.0 compression and use some thin head gaskets. FelPro makes a .015" one that works with aluminum heads.
Once you have heads and compression figured out...then you can select cam. Having better heads and compression will really allow a good cam to work.
If you decide to stay with current setup and you don't pull heads (that .015" gasket would even help the iron heads!), then I'd look for a relatively short duration cam with a tighter LSA to help wake up that low compression.
If you can do the port work on stock heads...then go for it. But no way would I spend the $$$ to pay someone to mess with them. Not worth it. It's cheaper to just buy something better.
What trans and gears do you have?
JIM
If you change heads I'd go for some 64cc chambers. That will get you up in high 9's...close to 10.0 compression and use some thin head gaskets. FelPro makes a .015" one that works with aluminum heads.
Once you have heads and compression figured out...then you can select cam. Having better heads and compression will really allow a good cam to work.
If you decide to stay with current setup and you don't pull heads (that .015" gasket would even help the iron heads!), then I'd look for a relatively short duration cam with a tighter LSA to help wake up that low compression.
If you can do the port work on stock heads...then go for it. But no way would I spend the $$$ to pay someone to mess with them. Not worth it. It's cheaper to just buy something better.
What trans and gears do you have?
JIM
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Melting Slicks
Joined: Dec 2000
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From: Carmichael CA
Don't use the old cam...get a new or reground cam. Cam bearings are just aluminum sleeves and both the bearings and cam get severe wear from even light use. If it's just had 500 miles on the cam bearings then I don't think you need to change them, but definitely don't put a cam in there that has more than 15,000 miles on it.
I believe the 268H from Comp Cams is identical to the original L82.
I believe the 268H from Comp Cams is identical to the original L82.
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From: Charlotte North Carolina
Thanks for the advice. My son didn't have the patients to let me look at the Auto Fair, so I didn't see much as far as parts. Jim, I have a 350 turbo for a tranny and 3;55 rear gears. For the money, I like the idea of a shorter duration cam, tighter LSA and new gaskets. Just to see if it helps, new heads would be ideal but, I’m trying to avoid a couple of extra paper weights. "Rock n Roll" mentioned the 268H from Comp would that be a good consideration? Before I "put the buggy infront of the horse" Should I find out the compression first?
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Yes...if it's 70 psi of a cranking compression....we now know why it has little power. Something ain't right. Go ahead and check all of them to see if there are any burnt valves or leaking head gaskets.
The 268H is a decent cam but it's not a copy of the L-82. It's a single pattern cam with assymetrical lobes. It's a good solid design that runs well in mild motors. But we need to figure out the compression issue first.
JIM
The 268H is a decent cam but it's not a copy of the L-82. It's a single pattern cam with assymetrical lobes. It's a good solid design that runs well in mild motors. But we need to figure out the compression issue first.
JIM
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St. Jude Donor '08-'09
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From: Charlotte North Carolina
I borrowed a neighbor’s gauge; the threads seem long so I didn’t want to tighten the treads too far in the cylinder. So it's either the tool or the user, I will get another gauge with a shorter thread and check again. Thanks for the replies
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From: Charlotte North Carolina
Prevuios gauge was bad, Bought a new one from NAPA. I have 145-150#. 6 out of the 8. Assuming checking each plug one by one is o.k. Or should I remove all the plugs then check?
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From: Charlotte North Carolina
Thanks, I'll start from the beginning. All plugs out, Throttle/choke wide open. I believe I'm off the HP question, trend should have been how to check compression., I'll start a new trend when I get a chance to start over. (kids,sports=busy week)Thanks again.
