Suspension lift with SBC conversion?

[ECKSJAY]

Hey all, didn't see any references to this while searching...

Have a customer interested in doing a SBC swap (please don't give the old 'just put a 4.3L in' deal, he's doing the SBC) and we need to know which lift to sell him. It's our understanding that there are some clearance issues, but we're thinking that it's the rear portion of the upper control arms. Would a kit like RE 5.5" with drop brackets be used for this? Who has done the swap who can answer this question? Need to know as many specifics as you can provide.

Thanks a ton, appreciate it!

Phil

 

[xjbubba]

The main issue, other than the need for at least 3" of lift, is clearance between the UCA frame mounts and exhaust manifold collector/down pipe. Using the stock truck manifolds required extensive butchering of the mounts on both sides, and the use of drop brackets, to get clearance. Even then, it was a bear to R&R the crossover pipe. Using center dump manifolds, like the early Vettes and trucks, or 84-86 truck manifolds will give adequate clearance.
Here's a couple shots of mods required to the UCA brackets when using stock '92(?)-'95 truck manifolds.

 

[ECKSJAY]

Nice explanation man. Appreciate the pics, they confirm what we suspected. Any particular reason that you used the stock 92-95 truck manifolds? Going by the rest of your drivetrain description, it didn't appear that you were short of any cash, but I'm assuming.

If I understand you correctly, you're saying that if he were to use tight center dump manis then you don't have to worry about control arm clearance? Just need maybe a 3.5" RE Superflex?

 

[xjbubba]

Calif smog laws required I use a truck engine because I wanted to use the NV4500 tranny, which was only available in a truck. They wouldn't let me use any other manifolds but those that came on a post '88 truck. Using early car/truck manifolds that collect above the spark plugs, and "hug" the engine give the required clearances, both for the frame and for the UCA. But you do need 3-4" of lift, minimum, to clear the arms themselves, when compressing the suspension. The 3.5 lift should be OK. Others have used the "rams horn" exhaust manifolds, and say clearances are good. The center dump may be a little tight on the passenger side, if you move the engine over the same as stock (I did). I've read that some one installing the 2.5" Vette manifolds had to grind a little(1/4") off of the down-pipe flange to clear the frame. I recently installed '84 350 truck manifolds. The clearance is great on the driver's side, and close on the passenger side, but totally acceptable. Manifolds off an early low performance Camaro are also supposed to work. Just stay away from the newer truck of car manifolds that collect below the spark plugs.
What I'm currently using:

 

[myjeepsbigger]

Any better shots of the steering box clearance? Factory steering box? What did you use for a radiator?

I'm getting ready to do an LT1 soon.

 

[xjbubba]

I used a Howe radiator (from Summit Racing), and a WJ steering box, as well as seriously modified the front frame horns to get it all to fit. The stock fan on the 350 just hit the stock XJ box, pluss there was no way to put a "real" radiator (defined as a radiator with total square frontal area equal to the engine cubic inches + 50) between the stock box and the stock frame. So since I was into "whacking and hacking" because of the manifold issues, I decided to get serious. Moving the stock box is difficult because there is an internal web that keeps the steering box bolts from crushing the frame. This web is welded from the exterior as well as on the inside of the frame! Pluss, I found the steering shaft angles got too severe, and hit the frame. So, after crawling arround under a neighbor's WJ, trying to figure out how they stuffed a 5.9L V8 in there, and cooled it too, I decided to make the WJ box work. I also extended the frame horns ~1.5inches, the max I could go without modifying my after-market bumper. I used 3/16x2x6 tubing, sculptured to slid back into the frame rails as far as possible. I cut the inside and bottom out of the stock frame rails, and fit the tubing into the opening. I also drilled out the spot welds on the front cross member, and latter attached it to a new front cross member made from 1/8x1x1 tubing. The passenger-side frame was also notched to fit the radiator.
Here's a couple of shots:

Here' acouple more:

 

[myjeepsbigger]

I used a Howe radiator (from Summit Racing), and a WJ steering box, as well as seriously modified the front frame horns to get it all to fit. The stock fan on the 350 just hit the stock XJ box, pluss there was no way to put a "real" radiator (defined as a radiator with total square frontal area equal to the engine cubic inches + 50) between the stock box and the stock frame. So since I was into "whacking and hacking" because of the manifold issues, I decided to get serious. Moving the stock box is difficult because there is an internal web that keeps the steering box bolts from crushing the frame. This web is welded from the exterior as well as on the inside of the frame! Pluss, I found the steering shaft angles got too severe, and hit the frame. So, after crawling arround under a neighbor's WJ, trying to figure out how they stuffed a 5.9L V8 in there, and cooled it too, I decided to make the WJ box work. I also extended the frame horns ~1.5inches, the max I could go without modifying my after-market bumper. I used 3/16x2x6 tubing, sculptured to slid back into the frame rails as far as possible. I cut the inside and bottom out of the stock frame rails, and fit the tubing into the opening. I also drilled out the spot welds on the front cross member, and latter attached it to a new front cross member made from 1/8x1x1 tubing. The passenger-side frame was also notched to fit the radiator.

VERY nice work. I like the WJ box idea. I've already chopped the front of mine and shortened it....hopefully I can get away with it the way it is (LT1 doesn't run a mechanical fan) because I love the approach angle that I have right now.

This is about the only shot I have with me that kind of shows the approach angle.

 

[NSW Sparky]

I am a total Idot for asking was SBC stands for?
I am guessing its some sort of motor swap.

 

[98POSXJ]

Small Block Chevy

 

[whompinxj]

sSeet buggy.
Air shocks on the rear?

 

[whompinxj]

*Sweet*

 

[xjbubba]

Small block Chevy (SBC) install complete (almoast)!

 

[myjeepsbigger]

Air shocks on the rear?

Yep. Fox 2.0's.

Small block Chevy (SBC) install complete (almoast)!

REEEEALLY Clean!!! Very cool.