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Need Cam + Heads Advice

Rob79er

Well-known member
Joined
Apr 13, 2005
Messages
60
Location
Dallas, Tx.
I am a newbie so I don't really know all of the jargon yet as far as engine talk goes. Here is what I want to do:
I have a '79 L-82 that I have pulled. So far it has only been cleaned and checked by the machine shop. The shop recommends .020 over bore based upon what they saw. I would like to rebuild it as cheap as possible but with a little more pep than stock. I've heard that the stock #624 heads are junk so I was thinking of Vortecs or the Dart Iron Eagles. What Cam and/or Heads do you guys recommend as a combo that will achieve this. I want it to be 100% streetable without a lumpy idle---but fairly quick at the same time.....
I am open to suggestions...thanks
 
This thread should receive a lot of good ideas. I'll just start with 1. If you are boring the block, you are buying new pistons. If you are willing to use premium gas, consider raising the compression ratio. The size of the combustion chamber in the heads you decide on will have to be considered. I have a 350hp 327 with 11.25 to 1 comp. and it runs fine on pump premium. You may not want to go that high, but I would want at least 10.5. I'm anxious to hear other suggestions, there is a lot to consider. Just$.02 worth. Good luck

Mike
 
i would go with 0.030" over pistons, more common and a few bucks cheaper. what's your budget?? and how much power do you want?? a good set of heads will really wake up your motor. Vortecs are alright, but with the added cost of required new style intake, you can get a better set of heads that re-use your old manifold. your L-82 cam is pretty good for a daily ground pounder without a lope. bumping the compression to 9.5:1 with iron heads or 10.5:1 with aluminum heads will liven her up. a good exhaust is also key. you're good with stock rotating assembly to 375hp, more than that you should poney up and get the good stuff.

bottom line, i would bore it 0.030", zero deck block, balance the rotating assembly, invest in some AFR 180 heads and get a new cam. you should be able to get a solid 300-325 hp for $3000 when it's all said and done.
 
What about Edelbrock heads? I don't hear much about their heads, mostly hear about their intake manifolds and carbs.

Wouldn't some 1.6 roller rockers give him some more hp?
 
Edelbrock sells more heads than pretty much every other

non-auto mfg combined. Surprised you haven't seen more on them. All the entry level heads are decent. AFR's are kinda the favorite at the moment, TF got some bad press a few years ago with some QC probs on the final assy.

I have a set of Edel Perf - some of the least expensive. I have so many probs (and mine are highly modded) I can't be a source of recommendation for or against. Most of the big names are fine though. The Edelbrocks helicoil EVERY hole - I've never broken threads on one. You can't go much over 1.5 ratio on those without some minor mods.

Ditto on the .030 pistons - much more choice and cheaper. Go forged - cheapy forged budget claimer type aren't $100-150 more than nice hypereutectics, but are simply tougher. I would also go wiht forged rods and crank - cheaper ones won't go $300-500 over the best cast and you should be safe for anything. The factory cranks and the high end cast cranks are decent though - probably safe enough for 375-400hp, especially with billet caps and good fasteners on mains & rods.

Hyd roll setup costs you $800 over a hyd and only gives you so much more - on a budget it's not worth it at all. A lower priced set of at least name brand roller rockers is not a bad idea at all though. Do go with the highest dollar/highest strength anme brand timing set you can get - like cloyes, etc. You have some options like true roller, double roller, etc., but don't save $50 on that part whatever you choose.

Nearly everyone raves about the edel rpm air gap intake - me too.

I'm pretty freaky on distributors, having had a series of problems with them after decades without. Go with a really high end product or at least a new GM one. MSD Pro Billet are like another animal they are so solid. My cheapy Mallory blew up my last engine when the shaft developed a problem, ate the cap and ccaused one last crossfire between 5&7 at speed....my van destroyed its factory GM the same way with no other damage. Both are obviously good manufacturers - but the MSD probillet is just incredible it's so superior.
 
I would go for Edelbrock too. An Edelbrock street-performer cam with matching heads. Of course...roller rockers. In the future, you could always get the matching intake and carb. I guess it depends if you want your engine to look stock or not.

I would go with 0.30 over bore as well.
 
Flat-top pistons, 64cc-chambered cylinder heads, a hydraulic cam in the .450" lift/218* @ .050" lift/114* LSA range, a 'decent' dual-plane intake and 650 Holley carb, headers and exhaust (no cat ) should give you what you desire on AMOCO-93 or SUNOCO-94, without killing fuel-mileage, and provide good street manners (vacuum for brakes and lights), without the 'rump-rump'.....


Has similar set-up in my '79 Z28, using the OEM LM-1 as the foundation, and it ran mid/low 14s at 97 MPH, knocking-down 18+ MPG on highway trips with 3.42:1 gears on the OEM 225/70R15 Uniroyals.
 
From what I've seen, Edelbrock heads seem to be in the mid price range whereas AFR's are almost $2000!:W

What about having the stock heads worked on? Would aluminum heads from the L98 work on the Sharks?
 
Remember fellas: I am on a serious budget so no $2K heads for me.....
I'm not looking to build a monster but just something a little better than stock- say 275-325 HP....thanks for the tips so far...
 
That is why I'm suggesting the right pistons for a good compression ratio. It's too hard to do later. You can add heads, manifolds, carbs, roller rockers, and distributors easily later. But pistons, cams, oil pumps, and timing gears are much more expensive to do later. Find out what size combustion chamber is in your stock heads and buy pistons that will give you respectable comp. Consider that later you may change heads and get smaller combustion chamber heads to raise the compression even more. I recommend cast pistons also. Forged are stronger but they expand more so they must be fit looser often causing piston knock when cold. Buy a good oil pump, timing chain assem. and a roller hydraulic cam if it's in budget. If not a good regular hydraulic cam. Build a good short block, from the heads on up is all add ons. Again just my opinion.

Mike
 
Why not just get a crate engine?

For your stated HP goal and minimal budget, here is a NEW, WARRANTED, 290 HP GM engine for $1700. Or a 330 HP for $2400. Hard to beat the performance for the money, even though I tried. I spent over $3500 in rebuilding my engine just because I wanted to say "Yeah, I built it myself." I'll bet I'm not putting out anywhere close to the HP these are...

http://www.sdpc2000.com/catalog/120/GM-Performance-Parts-Crate-Engines.htm
 
I had a 350 engine from a '70 Impala built at D & K Motorsports in Helena, Montana. I had it decked, balanced, hypereutectic .030 pistons, and pocket ported the heads. I bought an Edelbrock cam, timing set and valve springs. They supplied the flywheel, balancer, Scat crank, tanking and machining. I have about $2500 in my 383 stroker.

They wanted $1500 for a standard 350 rebuild (with 12K/12 month warranty), $1650 with balancing. When I asked about a 383 upgrade, he said he would build it for $2000. He indicated interest in putting my combo (Performer cam and intake) on the dyno and we struck a deal-$200. 344 hp/434 ft. lbs. I put it in my '70 Chevelle wagon last June. Car idles smooth, good vacuum. It's on the dolly now and going into the 'Vette, since the Corvette's original engine broke-dropped a valve.

I suggest calling around to local engine builders in your area and try working a deal. Another good cam (in my '71 Nova w/355) is a Comp Cams 260. Also smooth and good vacuum. The other suggestions posted earlier were good as well. Remember-if you deck the block-you lose the numbers.

Rick
:w
 
Edmond said:
What about having the stock heads worked on?
Would aluminum heads from the L98 work on the Sharks?
" Generally-speaking ", the OEM heads from the late-'70s are small-valve, large-chamber, thin-wall casting 'junk', and (in my opinion ) spending any real-money on these would be just wasted:
I also believe the L98 aluminum heads are (or were ) the hot/budget set-up for some decent builds, including guys who build Cross-Fire Injection cars.....

maybe Twin Turbo can offer insight.....
 
Also interested

I've been watching this informative thread also. Man, 3K for a 383 stroker w/425 hp, 3 yr. warranty and free freight is hard to beat! I just had a local shop quote me $2800 to rebuild and balance my SHORT BLOCK ONLY! That's if I deliver it to him.

Bill
 
The stock cam in your L82 is the old 350 350HP cam and is a good choice for your goals. I would mill the heads .030 to get the Compression up a bit. A good true dual exhaust of like 2.5" will help alot on your car. With the CR between 9.5:1-10:1 and a good state of tune you can achieve your goals. The factory left some HP untapped in that engine stock because of emissions. A good recurve of the Distributor and richer secondary rod in the QJet carb will help alot also along with the bump in Compression and free flowing exhaust. One other thing that will help that car especially seeing it is an L82 would be a 2500 stall converter in the trans. That will make alot of differnece in the off the line punch. Keep us posted.

:beer
 
AFR's are not $2k, they run about $1100. Edlebrocks are about the same price, unless you find a smoking deal plan on $950-$1100. the AFR's are fare better heads. Edelbrock just copies GM's Vortec design anyway. the stock heads on your motor are thin casting big chamber heads that will crack if you port them. the GM perforamance 330 HO runs $2400 and comes with a warrenty. but remember that the new GM crate motors require a Vortec bolt pattern intake and different flywheel/flexplate.
machine work on an old block for decking, boring and honing usually runs $7-800. $1200 for heads, $300 for pistons and rings, $150 for gaskets, $120 for timing chain, $200 for cam in lifters, $50 for rockers, $50 for bearings and $150 for new distributor puts you near $3k. a set of Trickflow heads will save you about $500 and still work for your build. any way you slice it, a warmed over rebuild or crate motor will set you back about $3k.
now re-using your heads and just running some higher compression pistons and better cam with get you 250hp for about $2k.
 
275-325HP keep it simple

Rob79er said:
I am a newbie so I don't really know all of the jargon yet as far as engine talk goes. Here is what I want to do:
I have a '79 L-82 that I have pulled. So far it has only been cleaned and checked by the machine shop. The shop recommends .020 over bore based upon what they saw. I would like to rebuild it as cheap as possible but with a little more pep than stock. I've heard that the stock #624 heads are junk so I was thinking of Vortecs or the Dart Iron Eagles. What Cam and/or Heads do you guys recommend as a combo that will achieve this. I want it to be 100% streetable without a lumpy idle---but fairly quick at the same time.....
I am open to suggestions...thanks

Remember fellas: I am on a serious budget so no $2K heads for me.....
I'm not looking to build a monster but just something a little better than stock- say 275-325 HP....thanks for the tips so far...
You're not asking for a lot ... you don't need a lot ... you don't need to spend a lot. The $1700 290HP crate is a good choice ... may make best sense for your purposes. But if you're gonna build ... consider two approaches:

GM Iron Vortec heads and either of these 3 Speed-Pro Hypereutectic pistons: Flattop P/N H669CP (about 9.8 CR w/Vortecs) or Flattop P/N H345NCP (about 9.4 CR w/Vortecs) or Dished P/N H670CP (about 9.2 CR w/ Vortecs). Use your cam or a similar grind. The iron Vortecs are great performing heads but you'll also need a different intake manifold and valve covers to fit Vortecs.

If your 624 heads are structurally OK and don't need surface milling/decking, simply have the 624s' valves reseated & serviced w/ a $25/set of new "Z28" springs and run your intake & w/Speed-Pro Hyper low-dome P/N H618CP (about 9.4 CR w/ 624) & similar cam choice as above.

All the Speed-Pro Hyper pistons mentioned are available new w/ rings for under $225/set. New Iron Vortec heads around $500/pr. New Vortec-type intakes run $120-$250. Install $45/set ARP rod bolts in your rods & have your rods' big ends resized/checked for size ... or buy a new $225 set of Scat/Eagle rods. The L82 cam is pretty good, but wide variety of newer profile hydraulic flat tappet cams available w/ new lifters for under $100. For cam, Don't exceed 235* duration @ 0.050" and stay under .500" valve lift. Good hyper pistons are plenty for your HP range ... forged pistons wouldn't add a thing but cost. These choices can get you into your 275-325HP target range and hold up quite well. G'luck!
JACK:gap
 

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