TBI to BBD adapter plate

[Grand_Wag_85]

Anybody know of an economical adapter plate to mount the GM TBI on a stock 258 BBD intake?

[tgreese]

I just made one. Definitely the cheapest option.



http://fsjnetwork.com/forum/viewtopic.php?f=35&t=2468

Another possibility is to use the Ford CFI throttle body instead of the GM TBI. The CFI has a Holley 2V pattern. Matching the GM TBI pattern is a pain. I'm sure there are other throttle bodies out there with friendlier patterns than the GM, but less well documented.

[Grand_Wag_85]

Does the CFI use the small venturi pattern? I'm going the GM route just because I already have the parts but the adapter plates all appear to be in the $160+ range. What type of setup did you use to make the big holes?

[FSJ Guy]

Welcome to the dark side!!!!

Might want to inquire at a machine shop to see how much it would cost to punch two big holes. You can use the gasket as a template for the other three, but heck, while it's there, have the machine shop punch and thread the other three, too.

[Bill usn-1]

My prototype is being developed at the CNC shop right now.
It should be just like my others at $80.

The 2 big holes need to taper in to allow the transition from the 1 11/16 TBI to the 1 1/2 BBD bore size.
The 4 mounting holes are very close to the bores.
I have 1 that's 3/4' thick but I'm trying to keep all of mine at 1/2" for hood clearance in different vehicles.

[tgreese]

Does the CFI use the small venturi pattern? I'm going the GM route just because I already have the parts but the adapter plates all appear to be in the $160+ range. What type of setup did you use to make the big holes?

AFAIK the CFI throttle body is the same pattern as the Motorcraft 2Vs that the AMC V8s use, and same as the Holley 2V. I'm just relying on the info from Will Marsh's series about putting one on the manifold of his Travelall. http://www.binderplanet.com/forums/show ... hp?t=53524

Discussion at the link above covers what I did to make the adapter. I was given the aluminum, and I used my sawzall to cut it to the approximate size. I cleaned up the edges of the adapter with my stationary disk sander. The pattern was laid out using the gaskets for the manifold and the TB.

We have some large drill bits at work, and I drilled the largest hole I could (7/8"? don't recall) through the area overlapping the two patterns. Then I used my die grinder and a non-ferrous metal bit to enlarge the holes asymmetrically to match the pattern on each side.

The burr I used - http://www.amazon.com/gp/product/B00385 ... UTF8&psc=1

There is some more discussion on the thread I linked above.

[tgreese]

...
The 4 mounting holes are very close to the bores.
I have 1 that's 3/4' thick but I'm trying to keep all of mine at 1/2" for hood clearance in different vehicles.

Yes. The bolt holes partly overlap the TB bore. To anyone that makes their own adapter, I suggest you do not use the fancy countersunk bolts that I used, and instead use socket cap screws like the Howell adapter.

My adapter is 1" thick ... but that's the material I had. We'll see how it works re hood clearance. I did some rough measuring at the time, but I don't recall how it came out. I'll look at it again this weekend.

[Grand_Wag_85]

Sorry Tim I just briefly buzzed thru your thread and musta missed those parts. My head is still spinning from all the reading on BP.

Ethan, dark side indeed! My goal is to do the speed limit on 70, that's it really...LOL!

Bill, any idea on when it'll be ready? Don't think hood clearance will be much of an issue for my J10. I can stick a camera in there and shut the hood if you need. There's a 32/36 on there right now.

[Bill usn-1]

My CNC shop said about 2 weeks.
Keep in mind I design to work on many applications. The AMC 6 was also used by IH and used in passenger cars.
So I have to keep all applications in mind as I design them.

[carnuck]

I've been looking into using a throttle body from a Grand Cherokee 5.2L on my stroker 4.7L motor.

[Grand_Wag_85]

I've been looking into using a throttle body from a Grand Cherokee 5.2L on my stroker 4.7L motor.

Is that one for the Comanche or the Eagle?

[carnuck]

My '84 J10

[Bill usn-1]

Isn't the TBI an offset 4 bolt pattern?
I did a dodge TBI on a 4bbl manifold adapter for a guy with a 5.2l when he changed to an aftermarket manifold.
There is also a small and large TBI bore just like the GMs.
My BBD prototype is in the mail from my CNC shop so I should have it soon.

[carnuck]

Mopar throttle body top view

JGC-TBI.JPG

Mopar throttle body bottom view (haven't compared to the BBD pattern yet)

52TBI.jpg

Mopar TBI to 4 bbl adapter (I had a Clifford intake to put it on)

tbody.gif

[Bill usn-1]

That looks like the MPFI throttle body like I showed in the MPFI conversion using the 7427 PCM with 4l80e.
That is different from the Mopar TBI throttle body with the injectors like the GM TBI.
Are you talking TBI or MPFI.
I have done adapters for both.

http://www.binderplanet.com/forums/show ... p?t=102689

[carnuck]

Sorry. I meant just MPFI throttle body. Soooo tired this past couple months

[Grand_Wag_85]

Any updates on the adapter plates Bill?

[Bill usn-1]

Just got the first batch in this week.

HFI 2-1 - Copy.jpg

HFI 2-1 (3) - Copy.jpg