snb73

I have a 73 L-82. Should I rebuild it? I want to get about 400 flywheel horse-power. I want the benifits of keeping the forged crank, can I re-use the rods? I know I need to buy new pistons. I want to use Comps 268XE, Trick Flows, and an RPM.

My other option would be to buy the Gm Goodwrench 350. I'm taking about the LM1 motor, cast crank and cast pistons. I'd add the cam, heads and imtake to this block.

My delemma is this, do I rebuild my stock motor: $1000 labor for blockwork, $350 for rods, $350 for pistons. Keeping the internals forged. Or do I go with the brand new cast crank/piston motor for $1400.

Like I said, either choices will recieve trick-flows and an RPM intake.

Should I go forged or cast? I want to be able to take the motor to 6000 safely. 5500 routinely, 5800 occationally and 6000 rarely.

Thanks, Steve.


[Modified by snb73, 10:58 PM 10/6/2001]

tnt76vette

Sounds like you already got your game plan....but I dont think an RPM manifold is gonna fit under your hood....it be too tall :nonod: :flag

yosshimura

If you do go Crate...please keep your original motor, so you still have the matching #'s engine :yesnod:

I would probably rebuild the original a little more stout than stock :D

Vetterodder

It sounds like you only want a short block and it also sounds like you're not afraid to turn a wrench. I'd go for a rebuild of what you have or buy a rebuilt short block. That way you won't be paying for pieces you don't use and you can reuse more of what you aleady have. You'll also be able to select EXACTLY what you want and won't have to upgrade later (or wish you had to begin with). Performance 4 bolt 350 short blocks are routinely advertised for $1100 - $2000, depending on components, and 383's are about $300 more. At the power level/rpm range you seek forged pistons and crank aren't required but, if they help you sleep better, may be worth the extra cost. Unless you want to go with a longer rod, your stock rods are good to re-use with re-sizing and new bolts. Just take them to your machinist with the new pistons and they'll take care of the rest.

Dave68

I personally have never heard of a rebuilt small block going over 50,000 miles without major problems. I've had my 327 rebuilt twice and after the second time, I realized that thre aren't many people out there who know how to build engines so that they will last. For this reason, I purchased a ZZ3 (back quite a few years ago). That engine is brutally strong and will last a long time if taken care of.

Go with the crate; you'll have far fewer worries in the long run.

Gordonm

I have seen many rebuilds last a long time. I got my short block brand new from GM. I took it to my shop who builds race engines. He showed me the sloopy work GM does. The tolerances were way off. OK for a daily driver but if you are going to turn any rpm they better be right or parts will fly. Gm builds many motors an hour. This guy takes hours to rebuild one motor. I'll take my chances with a good machine shop any time. I stress good shop. There are a lot of sub par rebuilders out there. Choose wisely. The cheapest is not always the best. Speed costs money. Choose good parts and have them setup properly and the motor will give you many miles of fun.

snb73

Thanks guys. I was planning on goeing with the GM Goodwrench Universal 350 as my base for the engine. I'm still conserned about durability with the cast crank and pistons.

Steve

xfactor974

Think about this too. If you use cast pistons in your engine any rpm's over 3000 will wear them down. So if you are routinly shifting at about 5500 you willl definitly kill them cast pistons. I would go forged and give yourself the peace of mind that comes along with it. As for the cast crank, the stock GM crank and cast rods are good to 6500. That's plenty. And they should be able to handle around 450hp with no problem.

tsw71

I vote for the rebuild of what you alredy have. Since you already have a 4 bolt main and forged crank, the only thing you will really need are some new pistons for the overbore. I would go with the hyperuetectic pistons. From what I have heard, these will work up to 7000 rpm. As far as rods go, what you have will work fine. If it would make you feel better, then you can have them reworked or just get new ones. Replace the rod and main bolts with ARP fasteners. For the RPM range you are planning for, these parts will be more than enough. Be sure to have the rotating assembly balanced too.
For the record, I shift at 5700-6000 with my 385 gross hp 355 using 2 bolt main, cast crank, and forged pistons. The only thing I did was to replace the rod bolts with ARP bolts. It has stayed together for many years, which is pretty good considering I beat on the motor regularly. The only week link in my motor is the stock rods, but they have not caused me any problems yet. I must say that 6500 would make me nervous though. I may be wrong, but I believe that your L-82 rods are stronger than mine, so I wouldn't worry about them.

Tom

Dave68

I forgot to mention that the shop that rebuilt my 327 (the second time) was a nationally-known shop that was featured in "Chevy" magazine, "Hot Rod" and others. They said the same thing about sloppy build quality, but I can guarantee you that my ZZ3 would've blown away the original 327, even with Engle cam, headers, etc (recommended by the famous shop).

Remember too, that that "sloppy" GM makes the LS6 and LS1 blocks by the thousands every year. This is 2001 - times have changed!