Hey guys. I've got an 8.1 vortec big block:grinpimp out of a '01 2500hd and i'm going to put it in my '83 gmc K25. I want to run a manual tranny and was wondering if a nv4500 would work with this motor? If so What would my clutch options be?

i'd go with the sm465 over the nv4500

What is the horse power rating of your big block? I had a SM465 in my truck, and swapped in a NV4500. I have a 383 stroker pushing 550/550 @ 4400 dyno at the rear wheel, and the NV4500 holds up just fine. I love the overdrive as it brings my RPM's to 1850 @ 65 mph. Can't beat the toughness and the fuel savings.

What is the horse power rating of your big block? I had a SM465 in my truck, and swapped in a NV4500. I have a 383 stroker pushing 550/550 @ 4400 dyno at the rear wheel, and the NV4500 holds up just fine. I love the overdrive as it brings my RPM's to 1850 @ 65 mph. Can't beat the toughness and the fuel savings.

Not to hi-jack the thread, how is that 383 set up that allows that kind of power at that RPM?

To the OP, I would look into running the ZF-6 since I do think that was an option for that engine.

[QUOTE=axisT6;9809013]Not to hi-jack the thread, how is that 383 set up that allows that kind of power at that RPM?
QUOTE]
the guy who used to build my dads motors ran a circle track car with a 383 in it and he would run close to grand all day claimed he had it to 5800 one time

i'd go with the sm465 over the nv4500

Explain?

Im very familiar with sm465s, and have a bunch. Very little experiance with nv4500s other than driving them and I'm sure that if I was taking the time to put in a 8.1, I'd buy an nv4500(even though they're and easy grand around here)

Not to hi-jack the thread, how is that 383 set up that allows that kind of power at that RPM?

To the OP, I would look into running the ZF-6 since I do think that was an option for that engine.

My 383 Stroker was professionally built by Mr. Janke of Janke Engines of San Antonio, TX. Its a true 383, Forged crank, racing pistons, 11:1 compression, Dart Pro 1 Aluminum CRC heads, roller rockers working a Competition Cams aggressive cam. That's all I know. He put a lot more into it. Trade secrets. Mr. Janke knows his stuff. My engine was specifically built to put out that HP/Torque ratings because I'm a mudder and need the tire spin down low.

Mr. Janke has been building engines for over 40 years from Nascar to dirt track to street. I've seen him build 454's dynoed at over 900 HP and 750 ft/lbs of torque. That's not the biggest he's ever built.

Just to answer his question. Sorry 'bout the HJ. Back on topic. :D

The NV4500 should be just as strong if not stronger than the SM465 plus you get an overdrive.

I would stay away from the ZF-6 because they barely hold up to the horsepower of a stock 8.1L whereas the NV4500 can handle the power and then some with future power mods.