A thought about the plenum
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From: Key West, Florida!
Car: 89RSconvtZZ4TPI
Engine: ZZ4TPI
Transmission: 700R4 TRIPP TRANNY
A thought about the plenum
Would there be any benefit to adding an extention to the top of the stock plenum? I know this sounds far-fetched but would this help? I'm talking about cutting the top off the plenum and adding a box to the top for more air capacity in the plenum. Probably a very stupid idea but wasn't that all the SLP T-Ram was, other then different runner lenght and intake? Thoughts?
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Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
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Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
You know Ive thought about the same thing but instead of cutting the top out, I thought about adding a spacer between the TB and plenum. Kinda like a carb spacer except much thicker adding more volume to the plenum.
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From: Key West, Florida!
Car: 89RSconvtZZ4TPI
Engine: ZZ4TPI
Transmission: 700R4 TRIPP TRANNY
I thought about the spacer (keep heat away from the TB) but that would throw off the throttle cable/TV/cruise cable lengths, though there may be enought play to stretch.
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Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
------------------
Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
Thread Starter
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Joined: Jul 1999
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From: Key West, Florida!
Car: 89RSconvtZZ4TPI
Engine: ZZ4TPI
Transmission: 700R4 TRIPP TRANNY
The only spacer for TPI tb's that I have seen is a nitrous plate. There are plates for the regular variety TBi (L03).
------------------
Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
------------------
Rob P
89RSconvtZZ4TPI
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
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Joined: Jul 1999
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From: Shelby Twp., Mi., USA
Car: '84 Fiero ('01 GA interior)
Engine: '96 4.0 Aurora
Transmission: '96 4T80E
I don't think a TB spacer would do much, volume wise. The difference in volume would be small because of the large volume already present. You'd probably get more from porting the heck out of the plenum. Without changing runner length, I don't think you'll see much improvement.
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In the new Summit catalog (pg 74) There is a spacer you can buy for TPI TB. It doesn't say for camaros or firebirds but you can get the one for the chevy pickups it'll work on our 48mm TB.
There are other companies that sell the same thing but charge double the price!
There are other companies that sell the same thing but charge double the price!
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From: Readsboro, VT
Car: 85 IROC-Z / 88 GTA
Engine: 403 LSx (Pending) / 355 Tuned Port
Transmission: T56 Magnum (Pending) / T5
Axle/Gears: 3.42 / ?
When did chevy trucks ever use a 48mm tb? I thought they went from tbi right to the vortec multiport system that used a single blade throttle body?
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The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah
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The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah
No, the picture shows it for TPI Throttle Bodies. May be different year, say the 93-95 pickups? You can call them to check it out and they will try to help as much as they can. 
I didn't order one so I can't say proof positive but ... call and ask.

I didn't order one so I can't say proof positive but ... call and ask.
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From: Readsboro, VT
Car: 85 IROC-Z / 88 GTA
Engine: 403 LSx (Pending) / 355 Tuned Port
Transmission: T56 Magnum (Pending) / T5
Axle/Gears: 3.42 / ?
I looked in my Summit catalog last night and the only spacer I saw was an orange-ish spacer that's designed for the TBI trucks. There was never a GM truck that used the double butterfly 48mm throttle body, therefore it stands to reason that there isn't a spacer for it, because people don't make add-on products for devices that don't exist. Well, maybe the government, but they don't count.
------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah
------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah
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