Just dreamin, dont know if I could afford to do this at this point but figured I'd ask...  My 81 has the trans and rear done (3:55s).  Im dreaming or thinking about ETs now..  My car is street driven, it will never see a track.  But, my Moms Camry will take it..  LOL...  Do I change the heads and cam or should I just think of a crate motor? 

Compared to what is available as "crate" these days, a head/cam swap on a low compression engine doesn't look like a money saver. It may be cheaper to go with a top end swap, but I don't think the performance gain would make it comparable to a crater in the end. Just my .02

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Joel Adams
C3VR Lifetime Member #56    
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

On a dollar for dollar basis, a crate engine is the way to go. You can buy them in many power levels, plus they have a warranty on them.

I'm not saying you can't get a 385hp engine for $3200, but that's probably a lowball figure, unless you do your own work and have access to a machine shop.

The entire engine is no stronger than its weakest parts. If you add new heads and a cam, your lower rotating assembly is still old and has some wear, so you won't get the maximum potential out of the buildup, unless you rebuild the entire engine.

You have to assume your block needs to be bored out...lots of machine time and labor plus new pistons...not cheap for quality work. New heads are a good idea either way you decide to go...a lot of money spent on your existing heads is better spent on new aluminum ones. Your crank would have to be polished...more shop time and labor.

A new crate engine also takes advantage of modern casting techniques and is very high quality, not that your original engine isn't. The new castings are generally somewhat lighter in weight. You can either save your original engine, or sell it to help offset the costs of the new engine.

You still have to remember that more horsepower creates more heat...you still might have to upgrade your new cooling system.

Also, and I know this adds significantly to the overall investment...think fuel injection. It's not a necessity by far, but you won't regret it in the long run.

Go get yourself one of those Camry engines....Your Vette is lighter weight so i'll bet you can take her

WoW ! Sure can't beat those prices.

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Jimmy B.
Just can't wait to get on the road again.

 
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KeBo:

Crate engine

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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.

Gurtz, Darryl; My motor is actually in great shape.  I have 65k on it.  My main reason for the change is only to improve performance.

Kevin,

Octavio, Oh yeah, NOTHING ever goes as planned!  My rear went from 2500.00 to 4200.00.  I hear rthe budget, add 25% and pray..  LOL...

I have a question concerning crate motors.  gmpartsdirect.com lists the LM1 350 engine at 250hp/304ftlb for $1,292, and the HP 290/350 with 290hp/326ftlbs for $1652.  Both need intake, carb, distributor, starter, waterpump, ect.  Anyone know what the difference is in these two engines which accounts fo the 16% increase in HP.  Is it just a different cam, or are the heads different?  Would it be better to buy the LM1 and use the $360 difference to replace the cam, and pocket the difference.

Same head specs...same compression ratio...different camshaft...different crankshaft. Both have 4-bolt mains on the crank. The 290hp has a nodular iron crankshaft (stronger) where the other has a cast crank.

If you buy the LM1 and change the cam, you'll lose the warranty since you modified it.

Depending on your finances, give thought to the 350HO/330hp engine. It gives the most bang for the buck.

I'd gotten my zz4 from Jeg's ... complete engine minus starter/carb/exhaust/etc.... best i recall, was around $3800, but that was 4 years ago...or was it 5?... anyhow i'll paste the specs

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StingrayJim
NCM Lifetime Member #1936

Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94

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I bought 2 out of 3 of my vettes for less than the price of a ZZ4, but one can't help but lust for an extra 100 + horses under the hood. I'm hoping to go there myself some day, but that much money would buy a lot of improvements on the other cars.

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Jimmy B.
Just can't wait to get on the road again.

 
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well guys im in the same boat To start off with the good point, my dad gave me the 80 4speed vette. It has 80,000 miles on the rebuilt motor. I took off the intake to have it polished and looked inside the heads and saw build up around the bottom of the valves, now I want a new motor. Scared to bye allum heads, dont know  if seals will blow. The motor is not smoking or burning oil. should I just ride out the waves untile Im really able to afford a good motor?  

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