Hey guy's already posted in racing section but does anyone know of a company or place that makes or modifys single plane carb intakes for lt1 (besides hogan).


Thanks ,
Kevin

 

I haven't looked at a GMPP catalog for a while, but they used to sell a 4bbl, single plane LT1 intake.

 

Yes GM makes a 4bbl intake but it's a dual plane..... both the LT1 and LT4 versions.

You'll need to find a compotent machinist to modify an older gen single plane intake. It shouldn't be too difficult for someone with the right equipment. The center hole pairs need to be plugged/welded and the new holes need to be drilled at the right locations and at the correct angle.
Chances are, any race engine shop could do the work...... even better are the chances that they've never specifically done this but if you explain to them what you're trying to do I'm sure they could help.

Good luck.

-Mindgame

 

Well, like I said, I haven't seen a GMPP catalog for a while, but I'm pretty sure that there was one.

If you have a standard SBC manifold that you want to use, it really isn't _that_ hard (easier then going the other way). All you need to do is fill the stock center bolt holes (I'd recommend epoxy/jbweld over welding, if ou weld it you're guaranteed that you'll get some warping), and then just drill new ones in the correct locations (use an LT1 intake gasket to locate them).

You shouldn't have to do aything with the coolant passages... in the manifold since the LT1 just won't use them.

 

Nah, you can stay away from warpage by using wet rags and working opposite holes. Even better if you use 7/16" aluminum round-stock as plugs and chamfer the top side for weld penetration. Then you don't need to do as much weld-filling. I've done this on other manifolds with good results. But yeah, I'd still have the manifold faces cut (clean up) for safe measure.

The other problem with doing this is the fact that the hole pattern (LT1) is further apart, which usually puts a hole(s) in a scalloped-out section of the manifold. Looked at this option a bit when I was making up my mind with my build. So, you'd need to add an aluminum flange to those scalloped sections for the bolt to clamp.
May be able to find a manifold that doesn't have that problem but I have a Brodix, Victor Jr and Team G..... all would have required a flange.

Good luck.

-Mindgame

 

Huh... sounds like a similar approach to what I actually do. I've got some 1/2" aluminum rod sitting in the basement and a 1/2-13 tap and die. I'll thread a piece of the aluminum and tap the hole, thread it and the hole and cut it off. I make it permanent by either coating the threads with JB weld or sweating in some aluminum solder/brazing rod. What's nice is that even if you leave it bare, either one of these is fairly hard to see in a machined surface, just looks like some casting porosity... Works great for plugging things like severly overbored TB castings that broke into something like a ported vacuume port...

But from what I've seen, most people just tape off the flange side and pack it full of JB weld, and I've never heard of it popping out. I just don't trust that as much as a threaded aluminum plug.

I'm not sure what you mean by "scalloped-out," maybe because I've only done this the other way around (LT1 manifold on a SBC), which puts puts the new bolt holes in a location where you have to trim off some of the wierd casting stuff on the LT1's flange.

You're only moving the bolt holes a fraction of an inch, and I wonder how important it really is, since SBC guys running '87 and up heads always seem to get away with just slotting the center bolt holes and not even using the correct angled washers, and later GM just completely eliminated the inside bolts on the vortec/fastburn style stuff.

 

Hey if you do find somebody who makes one please let me know. I am runing the duel plane intake from gm on my 383 lt1 stroker and am running 11.4 at 120mph. I belive that i can get some more out of it if i had a single plane.

 

If I remember correctly it was Kinsler fuel injection offers a single plan high rise cast alumn. intake for the higher horsepower/higher rpm setups for either carb or throttle body with or without injector bungs.

Call Wade at ARE he was the person that told me about it. I know he can get you taken care of. If not Kinsler I know he is getting them from somebody because I seen one on a LT1 he built and converted to throttle body application.

 

If you can get in touch with Chuck Riddeck (criddeck@hotmail.com), he'd be the guy to talk to. I know he has modified a Super Vic for 4bbl throttle body use (injector bungs and modified center bolt pattern) and I'm sure he could do the same to other manifolds.

-Mindgame

 

i have a single plane 4 barrel style with the bungs already welded in from Accel. But you do have to machine the correct bolt holes etc as is being discussed.

 

The intake ports on an LT-1 head are very similar to a cast iron Vortec head. In other words, the roof of the intake port is about 3/16" taller than a typical "old-style" Chevy SBC head. While the bolt pattern can always be modified it might be better to start with an intake that has RUNNERS designed to fit the taller Vortec-style ports. Intakes that fit older style heads don't always have enough "meat" in the roof to match them up against the taller Vortec-style intake ports.

The bolt pattern on an LT-1 head, while similar to a Vortec head is specific only to the LT-1/4- nothing else shares the LT-1/4 intake bolt pattern to my knowlege. Boy, did I learn that the hard way a while back!

 

You guys that have done the conversion and are still FI, what have you done about the vacuume fittings, the MAP sensor etc?

What type of ducting have you used for the TB?

 

JWINN, Kinsler just makes the 4-barrel throttle bodies, not the intakes. An Edelbrock intake was used, however it was converted from a carb style intake.

 

The vortec ports are like the LT4 ports, the LT1’s pretty much match up to a standard SBC port. I’ve got a few sets of each in the garage…