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Discussion Starter #1
The Accufab 8500 series 4-barrel throttle body.

We are pretty pumped about this one. It's been our contention that in race applications, the available intake air on naturally aspirated and/or nitrous equipped engines is too restricted. It takes about 12 times as much air as gasoline to create "fuel". Recent tests have shown significant horsepower gains with larger inlet air supply. We have seen this on the dyno and on the track with Accufab's dual-barrel "split Dominator" style throttle bodies, like the ones on Pat Musi's engine, and the ones on the new Sonny's engines, Dennis Ramsey's, Coughlin's, etc. Four of our dual-barrels will flow 7,396 cfm.

In many race classes, the racers are limited to a single 4-barrel carb or a single throttle body. We used a clean sheet of paper for this one and came to the conclusion that the standard intake manifold opening for the largest carbs available (the 4500 series) was just not adequate. Our goal was to develope a better 4-barrel throttle body, not to try and squeeze it into the existing 4500 series intake manifold inlet opening (an inlet opening that was originally designed in 1969). Our concept was to design a new 4-barrel throttle body, with a 50% larger inlet area at the base, and let the racers (or the intake manifold manufacturers) come up with better intakes to match the increased airflow. Racers are creative, they will figure out how to modify their existing 4500 series intakes to accept the 8500 throttle body (the bolt pattern is slightly larger) or better yet, use a sheet metal plenum style intake manifold.

Like everything we offer, the 8500 series 4-barrel throttle body is machined from 6061-T6 billet alluminum (and polished) and has the same size throttle bores (2.75-inches) as our "split Dominator" dual bore units. It flows 3,600 cfm @ 28-inches. If that's not enough, mount two of them together for double the volume.

Each throttle body weighs 3.5-pounds, compared to up to 13-pounds for a big 4500 series carburetor. The 8500's are actually smaller in overall size, too.

More air flow, more horsepower, less cost, less weight, what's not to like?











Orders are being taken now and they will start shipping by the end of next week. Call me for details and pricing, (909) 930-1751.
 

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My question has always been why havn't the sheetmetal intake companie's havn't wide'n the Carb top placment, I understand the math of lenght in runners and where there place'd , but is there a major difference on the width part?
 

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Looks good. Now to mount them on my car???? LOL!
 

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Discussion Starter #8
My question has always been why havn't the sheetmetal intake companie's havn't wide'n the Carb top placment, I understand the math of lenght in runners and where there place'd , but is there a major difference on the width part?
From what I've learned from discussions with Tim Hogan, carburetor placement on a sheet metal plenum-style intake is much more critical than throttle body placement. With the carb, air and gasoline is the final product and it needs to be nearer the runners. With fuel injection, the plenum fills up with air (assuming that the throttle body or bodies are large enough) and the gasoline is injected almost directly into the port. Big throttle bodies can be mounted almost anywhere on the plenum. With the dual-barrel throttle body units, they are typically "staggard" over the runners but there in on actual reason to do it that way. Most guys do it that way because that's where the split Dominators were mounted, and that's where the holes are in their intakes. The four dual-barrel throttle bodies could be mounted pretty much anywhere on the plenum and it won't make any real difference.


Here is a photo of our dual-barrel throttle bodies on Musi's engine. They are "staggard", just because "everyone mounts 'em that way", from what I can tell.
 

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George,

Than is one very nice work of art. I may think of removing my 104mm for one.

Glenn
 

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Professor
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Those look GREAT G. Good luck with them.
 

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damn it man! I called three times before five! No answer. Guess I'll wait til Monday to order. I have to have one of these.
 

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Discussion Starter #18
:) KINSLER MAKES A NICE ONE TOO :)


LOOKS NICE GEORGE
What everyone seems to have down in the past is to squeeze the openings down to fit into the 4500 style intake manifolds. Our first decision was to not do that. The manifold plenum opening under the carb on a 4500 intake is 4 3/4" by 4 3/4" (with rounded corners). Our 8500 requires a 5 3/4" by 5 3/4" opening (with rounded corners). 4.75" x 4.75" = 22 square inches of opening. 5.75" x 5.75" = 33 square inches of opening, and increase of 50%. The bolt pattern for the 8500 is only about 1/8th-inch larger, but the opening required is huge. The throttle body itself measures about 7-inches square and is 3-inches top to bottom. Our big Holley 4500 Dominator measures 12.5-inches by 7.75 inches and is 3.5-inches tall. Smaller on the outside and MUCH bigger on the inside. Each throttle bore (1 of 4) flows just under 925 cfm.
 

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What everyone seems to have down in the past is to squeeze the openings down to fit into the 4500 style intake manifolds. Our first decision was to not do that. The manifold plenum opening under the carb on a 4500 intake is 4 3/4" by 4 3/4" (with rounded corners). Our 8500 requires a 5 3/4" by 5 3/4" opening (with rounded corners). 4.75" x 4.75" = 22 square inches of opening. 5.75" x 5.75" = 33 square inches of opening, and increase of 50%. The bolt pattern for the 8500 is only about 1/8th-inch larger, but the opening required is huge. The throttle body itself measures about 7-inches square and is 3-inches top to bottom. Our big Holley 4500 Dominator measures 12.5-inches by 7.75 inches and is 3.5-inches tall. Smaller on the outside and MUCH bigger on the inside. Each throttle bore (1 of 4) flows just under 925 cfm.
Thats alot of freakin air there, I'm going to be building a(460 Ford .060 over bore) With descent heads and some turbos, have any suggestions.
 

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Ice Cream Wolfpack
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So if I buy one of these throttle bodies, you ship it out to me, and I call my credit card and cancel the payment, you will agree that you were not a victim of my crimes against you, you were accountable for your decision, and you were a volunteer?

Fucking retard. Hopefully these are better than the fucked up ones you guys have sold in the past.:smt083
 
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