Opinions on TBI to Quadrajet manifold adapter...

Anyone use one of these things?

See it here: http://69.20.110.81/index.asp?PageAction=VIEWPROD&ProdID=126093 It appears to line up the blades on the throttle body with the secondaries on the Quadrajet intake manifold. Using one would be easier than changing the manifold obviously, but I'm wondering if anyone's tried this and can give feedback one way or another.

Thanks, ~jp

Reply to
Jon Pickens
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It should work, They use secondary bores because primarys are too small for TBI unit.

Reply to
TheSnoMan

Reply to
David Johnson

My thoughts as well I would be worried about lean mix on the front cylinders. under light loads and idling,

Whitelightning

Reply to
Whitelightning

If you don't want to use a TBI manifold, use the GM 454 Adapter. Their is no Small block vs Big Block carb mounting differences. Only Spread bore (Q-jet intakes) and Sqaure Bore (Real Mans Intakes). GM used Adapters on 88 and up 454 TBI engines with a old carbureted intake manifold on them.

I have one such adapter and I aint coming off it. it's off a 93 3500 Cab & Chassis with Dual Real Wheels. Had a 454 TBI engine, a 4L80E transmission, still has a Dana 70 rear axle. Charles

Reply to
Charles Bendig

How do you figure that? They are all on a common phlenum and the 4bbl manifold will flow better than the TBI one that is pretty retrictive. I would use 4bbl manifold and a oversized TBI unit too because a bigger TBI will add little flow to a stock TBI intake.

Reply to
TheSnoMan

I'm actually watching a throttle body w/ adapter from an '89 GMC 454 on eBay right now.

My only concern was that it doesn't split into 4 distinct holes for the manifold, it just mirrors the outer shape of the carb's bore pattern. Wouldn't air flowing straight down and hitting that 'wall' in the center of the bore cause some sort of problem?

My manifold has 4 holes, 2 smaller ones for the primaries, and 2 biggers ones for the secondaries, which is the way all the Quadrajet manifolds I've seen are.

When I was shopping for the adapter to put the Edelbrock (AFB) on the manifold, I found 2 different types. The 'open' type, which takes the square bore and opened it up to match the Quad pattern, was cheaper and that's what I bought. Then after I bought it I found one that in my mind was better. It actually had 4 holes in it that smoothly angled away and got bigger to perfectly match the Quadrajet pattern. The second type would have to be better for smooth, turbulence free airflow, although I don't know how much of a difference it'd make at my RPM range (rarely above 3000 I'm guessing, haven't hooked up the tach yet). I suppose it might not really be a problem unless I was racing, but you probably know better than me.

~jp

Reply to
Jon Pickens

I did find this:

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Scroll down to the 4BBL and Quadrajet-style throttle bodies this guy is making. Very cool.

~jp

Reply to
Jon Pickens

Get a Torqurer II Intake use the 454 adapter, install, enjoy. You will thank me later. Charles

Reply to
Charles Bendig

I just checked one out. Looks like what you referred to as a "Real Mans Intake" :-)

I trust your opinion, but I'm curious as to why it says "Not for heavy vehicles (trucks, vans etc.); use Performer EPS #2701" on the description. I checked both manifolds, and the Performer is supposed to be good from Idle to 5500rpm whereas the Torker II is rated to make most its power from 2500 to 6500rpm.

Never heard of an intake not being used for heavy vehicles...

~jp

Reply to
Jon R. Pickens

Manifolds like Torkers are not the best choice for heavy vehicle because they lack low speed response and power because of their design. You want a manifold that has a lower RPM range for better power and responce in a heavy vehicle.

Reply to
TheSnoMan

supposed

Lots of times. The key is the Idle to 5500 vs. the 2500 to 6500 The first is going to give you power at the bottom end though out the mid range where a heavy truck or any vehicle towing needs, it but limit upper rpm. The second is designed for drag racing with a high stall torque converter.

Whitelightning

Reply to
Whitelightning

Yeah, I kinda answered my own statement after reading what I typed, LOL...

This head cold is making me loopy.

~jp

Reply to
Jon R. Pickens

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