Who knows of a multiport intake (87 and above, or a 400 sbc) single plane or dual plane manifold that will fit under the hood? I want to stick a throttle body on top of it or a custom made box like the stealth ram (no dont' want a stealth ram). Don't want to use a carb type filter setup, thinking about using a 90 degree elbo like on newer TBI setups. I know i can get a regular carb intake converted to multiport for $$ Don't want to spend $1K+ for the holley setup since i already have a throttle body/fuel rails and 28Lbs LS1 injectors. Can you buy the holley mutliport intake manifold by itself? Will stock fuel rails fit on it? Thanks.

 

I went to Mr Gasket's website a while ago, (parent company of Accel) and they have a separate part number for just the intake, as well as all the components in the whole kit. This is for a 4 bbl style TB or use an adapter for TPI style I guess. I then tried the part number at Summit's site and it was valid, and showed a price. Dont remember how much, and I dont know if it would be a problem actually ordering it but I guess it can be done.

 

Do a search on here... I'm in the middle of building them specifically to fit C4's. I've been using single planes converted to EFI for many years and can tell you A LOT has to be done in order for one to work nicely under a stock C4 hood...
-Jeb

 

At last look the search wasn't working very well and all i found before was carbs, anything specific you can point me too, i know space is tight. I'll check out that part number as well, thanks. Trying to do something different.

 

Found what your talking about, i'm more interested in the intake, not the plenum. I'll probably go with a throttle body on top of it if i can make it fit, a plenum box of some kind would be secondary and i'd probably weld one up myself. I take it there's no mods needed for the intake manifold? Seems a few guys here are running carbs and if it's modeled after the jr. then fitting should be no problem?? Thanks.

 

My original combination used a single plane I converted with a 4v throttle body. The problem you run into is that you have 9.10" from the front block rail to the bottom of the hood; a Super Victor intake is 5.6" and a 4v t.b. is 2.75" which leaves you right at an inch for an air filter. No conventional carb style one will work, not even a drop base. I fabricated a pretty killer aluminum airbox that used to K&N cone filters up where the factory filter assembly once was. It was nice, did a good job of filtering and looked killer but it also cost me between 40-60 hp (manifested in a 4-7 mph loss in the 1/4); this was on a 570 hp 396...

So, my conclusion here (and it's a VERY educated one) is that unless you plan on running a cowl hood forget a 4v t.b. if you're making any kind of power. I spent a lot of time and effort in building a single plane conversion for the C4's that works well and fits under the stock hood; I've also run every other combination you can think of for an intake and the single plane is by far the best. It just requires a considerable amount of work to do properly.

For bases (the intake itself) I would avoid the production castings put out by Holley and Edelbrock if you're planning on making any kind of power. The reason is that they cast the injector bungs down in the intake port and they restrict the air flow and you can forget cutting them out because the injectors will no longer seal. The only single plane out there that isn't built this way is the Accel 74041 manifold which is essentially an Edelbrock Super Victor (p/n 2925) with the bungs cast in it; you can certainly use this one. However if you follow my advice and don't use the 4v T.B. and go with the adapter plenum you will find a considerable amount of fabrication work remaining in order to fit a water neck and thermostat.
-Jeb

 

I can do the throttle body directly at 2", but still doesn't leave me much for a 90 degree elbo for the intake (not talking metal plenum box, talking the plastic intake duct). I can get a carb intake at about 3.x inches but don't know the performance numbers on that (plus have to fab a TB adapter).

Intake plumbing i'm talking about is similiar to this:



This one is my wifes 4.3L

 

Won't work man... Been there-done that. There simply isn't the room necessary. I'll get some pics posted of the different systems I used.
-Jeb