1LowC-body

I'm currently building a 1991 C1500. I just replaced my 4.3 with a factory 350. I'm getting ready to stroke out the motor now 383 and adding vortec heads, mild cam, and intake with a carb. Planning on about 400 HP. I have a NV3500 trans and have read on some other sites that people have had this trans hold up to 400 HP with no prob (i find it hard to believe). I know my trans needs rebuilt anyways because some of the bearings are going bad but i was just wondering if anyone out there has ran this trans on a motor with more than 300 HP and had any success? They don't make any rebuild kits to beef up this trans, only factory stuff. Money is tight right now, or i would be putting in a T56. I'm going to do that later on but i have almost everything i need to build the motor up and build the trans i have now so if i can get away with it i want to give it a shot.

Also, this truck has the 10 bolt rear end with the open diff. Anyone out there have a posi trac for this they want to get rid of? I might be setting myself up for failure , but i'm gonna give this a shot. Tell me what yall think.

Also, has anyone ran caltracs on a truck simular to this? How well do they work? My truck is slammed 5" in front and 7" in the rear and has BAD wheel hop. Someone from caltracs told me this would eliminate it and also stiffen up my rear end (which is exactly what i need).

Thanks for everyones help.

jamespeek

i have a '91 sierra with nv3500, too. do you have the hurst shifter or have you considered buying it? i think you have to do some simple mods for it to work on our year, just make a spacer really, but i think that would be the one best improvement in my truck right now.

how did you drop yours, front and rear?

i did belltech 2" spindles and 1" springs in front, but it only dropped it 2", but am putting the stock spindles back on next week, and the stock leafs in the rear with a few removed and some 2" shackles, for a 1/3 drop until i get things figured out. tires are stuck way out, belltech sucks for 88-98. i used belltech 4" leaf springs in the rear, and it rides smoother, but it does hop when i apply the brakes to slow down for a light or slow down quickly for something. is that the type of hop your talking about?

do you have any aftermarket shocks? i want to get the billstein monotubes once i figure out how to properly drop this thing, they are made for a 4/6 drop, but your not far from it. i'd imagine those would be better for controlling axle hop.

get an atlanta advertiser to find the posi trac, if your in decatur, ga that is...

jamespeek

oh, and no i only have a stock 350 in front of my nv3500, but want to put an LT1 in soon... so i hope it can take 300hp. otherwise, i'll do the t56 swap too

1LowC-body

For the front i used 2" drop spindles and 3" springs. I need to get it aligned too tho. The rear i used the flip kit with the c notch and the 1-2" adjustable hangers on the rear and the kit gives you a 6" drop and 1" with the hangers. Its really TOO low i don't recomend going any lower than the 4/6 because i had to cut my bed out for the rear diff it was pounding the bottom of my bed. And yes i got the toxic drop shocks they are nitro filled. The truck rides smoother now than it did when it was stock, not to mention handles a hell of a lot better. I just need to stiffen up my rear end because it has too much weight transfer when launching and get a rear sway bar and a better front sway bar. I'm prolly getting a set of caltracs i heard those were pretty god. All my drop stuff is DJM bought from stylintrucks.com. Its good quality stuff for the price, but i have seen belltech and it seems to be even better but you do pay for the difference. I havn't had a problem out of mine yet other than bolts coming lose because i was too lazy to re torque them after a few miles.

I want one of those shifters, i saw them on jegs for a little less than $300. I'm definitely goin to get one once i find out if this trans will hold up. Next week i plan on pullin the motor and trans and having my machine work done on the block and getting my trans rebuilt. Also going to spray my engine bay to match my truck and try to wire tuck a lot of my wires. I'm going carbureted so ill be doing away with most of them anyway.

jamespeek

the DJM spindles are actually better. you went the best route as far as maintaining original dimensions, the belltech spindles for our model trucks push the tires out 1-1.5", so just past the fender wells, not tucked in, doesn't look good.

i dropped my old 85 1/2ton 5/7 and had the same problem with the rear axle and bed. as far as sway bars go: i got a belltech sway bar for the front of it, but it didn't make much difference, but there was a subtle difference between stock and belltech sway bars. i was planning on getting a rear one, but after the front one made little difference, i didn't get it and wound up selling the truck later on. i had the belltech drop shocks with eibach drop springs and belltech spindles. the progressive rate eibach springs made the best difference in the handling and went well with the twin tube belltech shocks. have fun getting a sway bar under the rear of that truck with 7" of drop.

i don't know how much a pair of caltracs are, but you might want to see if 2500 light duty springs will fit your truck if money is an issue, then just readjust your shackle to 2" if it raises the truck, or remove a leaf or two from the 2500 springs. but, it sounds like you don't have any room left for shackle adjustments

1LowC-body

thats good to hear. If the belltech makes the tires stick out some that wouldn't be good because i already had to cut the lip off the bottom of the fender on the inside because of tire rub.

Those springs aren't a bad idea, ill have to check into that some more. Now i just need to figure something out about the my trans. Guess I'll be figuring it out for myself