Your guess of 425 hp and 450 lb-ft may be a little on the high side. The 425 hp may be attainable if you switch to a more current design on the inlet manifold, but your 450 lb-ft is definitely high. You're probably in the 410-420 range. This should move your little Vette with ease. Enjoy the power and top-down motoring!
LG4 RunnersQ I was very interested in the question from Bill Wivel and your response to him concerning swapping a 350 for his 305 ("Tired Monte," PQA, Nov. '06). I have a similar situation: an '87 IROC-Z with a Quadrajet carb 305, engine code H, LG4.
I want to upgrade to a 350, and all the crate engines I see in the catalogs refer to earlier years than mine. I also live in Arizona and am concerned with passing emissions. I was wondering if the same solution you offered to Bill would apply to me? I am concerned that the long-block may not fit my engine compartment without some modifications. If this would work for me, I was thinking of ordering the engine without the stock heads and cam.
I have the Edelbrock intake manifold currently on my IROC 305. I also have a Holley fuel pump, Pacesetter shorty headers, an MSD ignition, a Flowmaster exhaust, ram air, a K&N Filtercharger, and a high-performance chip. It runs great, but I probably have 50,000 miles of life left on the engine (so says my mechanic).
Anyway, if the same prescription you gave Bill would apply to my situation, I would substitute the heads with Chevy S/R Torquer heads, 76cc, '87-and-up, and of course use the same cam you recommended, with the new 350 long-block you suggested. What do you think?Edward FiliksMesa, AZ
A Bill Wivel's LG4-equipped Monte Carlo sparked more than a few questions. We got a question similar to yours from John Davies of Reno, Nevada. It seems the smog police are cracking down everywhere, and you need smog-legal engine packages for both your cars. You've got a Camaro, and John has an '87 El Camino. Let's briefly go over the original answer and add some new info to match your questions.
When replacing either an '82-87 LG4 or L69 in any of the Camaros, Impalas, Montes, El Caminos, or trucks, the base Goodwrench engine is a great one to start with; it's sold under PN 10067353. The upgrade components of an Edelbrock PN 3701 manifold and camshaft, PN 3702, will give you a great-performing, emissions-legal engine. As in Bill's case, I recommended he also install the Edelbrock TES system in his Monte. Ed, you said you already had headers on your Camaro. John, the TES system, PN 68793, will also fit your '87. El Cam. You will need to upgrade to a four-bolt, high-flow catalytic converter from either an '85 Camaro or an '85-86 Corvette.
Now let's talk about some new developments. Ed, if you would like to purchase the GM Goodwrench short-block, this is the foundation that the complete long-block is built from. You need to pick up short-block PN 12601517, which comes as a rotating assembly with no camshaft, lifters, timing chain and gears, or tin (pan and front cover). This is where you run into a little problem. In '86 GM changed the design of the small-block to a one-piece rear main seal. With this GM changed the oil pan and front cover, and they went to a one-piece oil-pan gasket. You wouldn't be able to use any of your tin on this engine. Ken at Burt Chevy says the short-block is only $300 less than the complete. You might be better off buying the complete long-block and selling off the heads to recoup some money. With the complete engine you would have a new oil pump, timing-chain set, good GM lifters that you could use on the new Edelbrock camshaft, pushrods, rockers, and tin.