ericjon262

I haven't removed the TB from the adapter yet, but here are several pics of what I think is one of the better adapters available (TBI to Q-jet) the only downside to the adapter, is that it is 1.25 inches thick, and our cars don't have alot of hood clearance. the casting number on the body is 14100837, the spacer is fully heated, but this could easily be stopped by plugging the coolant lines that go to the adapter on the front and back of the body.











the next few pictures show the distribution vanes in the bore of the adapter, I would probably remove all of the top one, and some of the bottom one. I do not know how thick the casting is, and thus how far it could be ported before hitting water, if you bypass the coolant heating feature, it's not as critical (JB weld) if you plan to heat the TB, then you need to be careful.

UnderCover89TBI

iTrader: (25)

So you are showing this for exactly what reason? For people wanting to put a 454 TB on a 4 bbl intake for a quadrajet? Sorry just not sure what this post is about.

ericjon262

it should fit any spread bore manifold, and it's heated, which my understanding is a plus on a tbi motor, esp when some of the best flowing manifolds (IE the edlebrock performer airgap) are not heated it also can be found at junk yards pretty cheap, which is a plus for someone on a budget, also, the adapter itself appears to be very well made, and thought out, not just a piece of plate aluminum with a few holes in it.

UnderCover89TBI

iTrader: (25)

I thought the goal of any engine was to get the fuel as cool as possible going into the motor? I dunno. A regular adapter looks better than that bulky thing in my opinion.

ericjon262

Everything I've heard about TBI motors says they don't like the airgap style intakes, I'm not sure exactly why, but I think it may have something to do with fuel puddling, and atomization issues.

RFmaster

Eric

I think you have an answer - cold intake manifold walls will cause fuel droplets to fall out from intake mixture and puddle. This is why when using AIR gap intakes a MTS (manifold temperature sensor) is needed to keep mixture under control - especially under acceleration. There are couple of threads dealing with this problem in DIY PROM section.

As for TBI adapter - it is a bit too tall for stock third gen hood line. Pre-heating TBI on top of cold intake intake is just asking for trouble. IMHO, since TBI is a wet flow intake system a fully heated intake works best over wide range of operating conditions. Now - for performance applications that's a different story all together.

//RF

thomas1976

If I remember correct, adding a spacer is used to help increase velocity of the incoming air, a bit like the longer TPI runner.
This would happen if the bore has a rather regular in and out diameter.
The one in the pics appers to mainly add plenum volume, wonder if that would give a snappier feeling.

ericjon262

what I'm looking at is 2 things, one it allows for a 2 inch bore TB with no modding to the intake at all, two, it's a fairly long smooth transition (if you remove the distribution fins), not just and abrupt sharp edge.

UnderCover89TBI

iTrader: (25)

but putting it onto a stock tbi manifold is out of the question. so if your doing an tb and intake swap getting a different intake and using this on could be an option. but if you do not have a cowl or hood scoop then it will not clear

ericjon262

Definitely out of the question for a stock TBI manifold, it's not the right bolt pattern.

thomas1976

Apperently not, http://www.castheads.com/faqs_intake_manifold.php


"Radius blended into the bottom" would probably be better then "increasing plenum volume".

Hood clearence aside, it would be interesting to do a comparison test with a performance spacer.