Here are some side by side pictures of the Edelbrock Vortec air gap intake manifold with adapter & 454 TBI and a stock GM TBIintake with a 305 TBI:
Top View comparison

 

Front view:

 

This setup should fit on the engine with a stock hood, if not then I will just have to go with a smaller (height wise) air cleaner.

 

Rear view:

 

Height of aftermarket intake manifold w/454 TBI:

 

ya think that will fit under the hood?

 

ya think that will fit under the hood?

 

The air gap manifold is not recommended due to it decreasing the temperature of the manifold. This causes the TBI to have fuel condense on the walls which can lead to detonation and other issues. TBI is designed to work with a fully heated intake manifold, the air gap is definitely not fully heated.

 

Don't think fuel puddling will cause detonation, but it does cause some funky tuning issues. Once you get in the throttle and air velocity picks up it starts atomizing the puddled fuel and in effect acts like a pump shot that you didn't want. So once you tune around this problem, your pump shot will all be messed up when you get in the throttle when there isn't this puddled fuel to act like a pump shot. I think thats whats causeing some of my tuning issues with my RPM intake, non air gap, and 454 TBI and a slightly lumpy cam. Velociy gets pretty slow with all these combined parts, just one of the tuning issues of TBI.

That thing is pretty tall. You need to go see how much more room there is above your stock setup. You could be pretty close to sticking the injector pod into the hood with that thick of an adapter plate. I know with my RPM intake and thick adapter plate I'm brushing the hood on my monte with a 3" fliter, and I have a ton more room than you guys.

 

Well I have a 650 carb set up with distributor as a back up. I would prefer to stay with the EFI setup but if things don't work out, then will swap induction system. I am still keeping my finger cross.

 

what adapter plate is that??? that sucker's massive!!

 

That's a pretty sexy intake.

 

If I were planning to use the Airgap intake and I was worried about hood clearance, I'd ditch the adapter plate and have the intake modified (welded) so that the adapter plate wasn't needed.

With that said, I never noticed how steep the runner entry angle is on the Airgap manifold (which is good for performance) versus the much poorer runner entry angles on the stock intake.

 

Holley 2" TBI to square bore carb

 

the holley plate that I'm selling is only .5 inch thick and it has a dual bolt pattern so it can be mounted offset front or back

if anyone's interested I can get the Holley part number for it.

 

Are you sure it's for 2" bore TBI AND square bore, not spread bore? I ask this because if you look, it takes more than just a 1/2" to get the 2" TBI to fit on a square bore manifold. Z28 boy had to modify his intake when it was using a turbocity 1/2" adaptor or else the throttle blades would hit and not open 100%

 

Purchased the adapter plate at http://www.cfm-tech.com/GMTBIPerformanceParts.htm for $60.00 plus shipped to my door. Here is a closer shot with the adapter plate on teh intake manifold.

 

2" TBI but it fits spreadbore-both front and back

 

http://www.holley.com/HiOctn/ProdLin...FIA/17-45.html
Bought this unit from Summit 4 years ago for $45.

 

86z, how much did you have to hog out the manifold to avoid having a lip under the the adapter plate?

Steve

 

I did not "hog out" anything from the intake manifold.

 

I guess I didn't notice that the adapter plate had the correct taper.

Steve

 

Awesome!

Sweet pics.

 

I will be assembling the motor this Saturday. This will be my first motor assembly but have books as well as mechanics on hand to give advice. For those have used ARP bolts on there engine, what are the torque specs for them. (About 90% of the bolts for the engine are ARP's)

 

Real quick... is that set up going to pass inspection in CA?

 

Nope, no egr.

 

Don't know if one is available for the Vortec heads or not, but a low rise single plane may have been a better choice.

I tried an RPM Air Gap manifold and had icing of the throttle blades on a 50 degree day.

TBI works well with single planes; it also likes a heated plenum.

 

Your going to have some fun hooking up the tbi. That adapter plate looks like one of those that locates the tbi in such a way that the throttle shaft is in the same location that one in a carbeurator would be. In other words, its going to sit farther forward with that then the stock intake.

 

Car is a MI car so no worry about smog tests. This is my project car that has been in the works for the past 2 years. I know I still have a lot of work ahead of me. I will have the car towed home from the auto hobby shop once the engine and tranny is installed this Wednesday. (Fingers crossed). Still need to get pushrods and new timing tape for the damper since the damper I have has the TDC located closer to the driver side rather than on the center. (I specifically told the sales person I needed the one for a 92 Camaro) I will be installing all new Earl's steel braided fuel line w/fittings, fuel pressure gauge, and afpr.

 

yea i had a similer adapter i was gonna install on my caprice ,but i got everything on and ther ewas no way the throttle cable and tv cable was gonna reach that far forward,i would thing about an adapter plate that locates the TB farther back.