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Author:  FrankRaso [ Tue Sep 28, 2004 8:03 pm ]
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I don't believe that Offy and Clifford use the same adapter plate bolt pattern. The Offy uses the small Rochester carb pattern of 3-7/8" x 3-3/4". I don't know what pattern Clifford uses but my understanding is that it is square so you can mount the adapter in any orientation. I have not made any provision for attaching a Lokar bracket. I see from your photos that is hangs down quite low and would probably hit the manifold the way I have it laid out.

I was holding off to fabricate these adapters until I got some feedback with the design. Now I know I should make a provision for a kickdown bracket. Are you using Lokar PN SRK-4000? From the Lokar web site, it looks like you could bend the bracket up a bit for some extra clearance. How low does the bracket hang below its mount?

I could make the adapter taller but I think hood clearance might be a problem. Would you be able to stick some Play Dough on your air cleaner lid to find out how much hood clearance you have? Another option would be to make an extended bracket mounting base to raise up the bracket.

I'm surprised that Clifford put a divot in their carburetor base. It looks like it should be for mounting the exhaust manifold. Is there any chance you could measure it up for me or, better yet, make pencil rubbing of it and send me a scan?

About the TBI to square-bore adapter you drilled out: the holes at the corners seem to be for mounting the adapter onto the intake. This would be the Holley 4bbl carb bolt pattern, wouldn't it?

Finally, after looking at the Lokar kickdown cable and bracket, doesn't it work backwards to what a Chrysler needs? When you open the throttle, you should be pushing back on the kickdown rod but the Lokar cable would be pulling. Am I missing something? Lokar makes another throttle & kickdown for the 904 transmission (PN KD-2904HT) but it doesn't look like yours.

I was expecting someone using the Rochester TBI to also use the throttle cable bracket, throttle cable, and gas pedal. The transmission kickdown would be connected to the transmission cable pin opposite to the throttle cable on the TBI throttle lever. The kickdown would work opposite to how GM kickdown works by being pushed rather than pulled.

Frank
Author:  Pierre [ Tue Sep 28, 2004 9:01 pm ]
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Tell me what you want measured, as long as it doesn't require me to take off the TBI from the manifold I will gladly do it. I haven't measured air cleaner <-> hood clearence, but it is tight. I'd estimate 1" give or take. I think the divit is part of the casting process, because as you see there is also a matching circular chunk of aluminum sticking up between the #3/4 runners. I may be able to find an old used gasket to measure the divit. I'll have to look tomorrow if I remember.

Yes, the clifford pattern is square. I was told it was the old smaller holley 4 barrel pattern?

The throttle cable is the top one. It pulls the linkage towards the rear of the car, making the kickdown cable go towards the front. The kickdown cable extends towards the rear of the car, (sorry, not familiar with trannys, so I may be using wrong terms?), a bracket included with the cable holds it to the transmission via one of the bellhousing/main body bolts, and it does a 180 then back to the kickdown lever. So when the cable goes forward at the linkage on the throttle body, the kickdown lever gets pulled backwards, instead of where the original design "pushed" the lever backwards.

The adapter came with my howell kit, that had 4 untapped holes for the current holley 4 barrel pattern (like the one on my holely 390cfm 4160 model 0-8007 carb) and 3 tapped holes for the throttle body. I drilled the 4 holes in the clifford square pattern. These screws - two of which you can see in the top picture I posted in the other linked thread, are flush with the adapter. They have to be, otherwise the other 2 screws that you don't see would hit the throttle body.

That is the SRK-4000 bracket, and the KD-2904HT kickdown cable.
Author:  FrankRaso [ Wed Sep 29, 2004 8:04 am ]
Post subject: 
I don't blame you for not wanting to take your TBI unit apart. Maybe someone has an intake sitting on a shelf that he could measure for me.

Anyway, if you have a chance you could measure the following for me:
* adapter plate thickness.
* height of the top of adapter above the intake manifold.
* vertical distance between the top of the adapter and the bottom of the kickdown bracket.
* horizontal distance between the center of the bracket hold-down bolt and the part of the bracket holding the cables.
* horizontal distance between the throttle shaft and the bracket hold-down bolt. Does this distance matter with the adjustability of the cables?

For hood clearance, take some soft putty like children's Play Dough and put a few lumps around the air cleaner lid where it looks like the clearance might be tight. Close the hood and start you engine. Put the car in Drive and with one foot hard on the brake, rev the engine as much you can safely do. Then stop the engine and measure the thickness of the thinnest piece of putty. That is your hood clearance. BTW, what kind of air cleaner are you using?

If you can find a used gasket, the simplest thing to do would be to take a photocopy of it and mail it to me. A gray-scale scan (~ 1 MB size) would be better. You can find my address at: http://cars.rasoenterprises.com.

I have designed the adapter plate so that the front of the TBI faces away from the engine. The easiest way to gain the clearance you need for the throttle cable bracket (SRK-4000) would be to mount the TBI so that it faces the engine. For the Clifford intake and its open plenum, there is a lot more flexibility in mounting the adapter on the adapter. The amount of plate and machining required would be slightly greater with the need for a Lokar bracket so the price would be a bit higher.

Frank
Author:  Pierre [ Wed Sep 29, 2004 1:50 pm ]
Post subject: 
Adapter thickness - 1/2"

Height of top of adapter above intake manifold: This varies, because clifford sloped their plenum relative to the intake so whatever you use above the adapter will be parallel to the ground (my guess is to keep carb bowl fuel even and not slanted with the engine because when car is on a level ground, the back of the engine points into the ground) Thickest part is at rear right, thinnest at front left.

Vertical distance between top of adapter and bottom of kickdown bracket: 1 5/8" (Note bracket thickness is approx 1/8" by itself)

Horizontal distance between center of bracket holddown bolt and centerline of cable: ~2 3/4" (Give or take a 1/16th, I was eyeballing centers)

Horizontal distance between throttle shaft center and bracket holddown bolt center: 2 3/4" (again, eyeballing centers). This distance does not matter with cable adjustment. Infact this distance has nothing to do with the cable or bracket, it is dictated strictly by the adapter.

Note, when throttle cable is actuated the adapter will want to pull itself forward and pivot towards the right on the mounting bolt. That is why they include provisions in the bracket for a phillips screw to put pressure against the adapter and keep the bracket from turning. I put a red arrow pointing at the screw in this picture: http://home.inreach.com/pierre/tbi_kit/ ... _arrow.JPG

I used a summit 14" aircleaner with 2" tall element. It rises about 3/4" or so at the base. I'm pretty sure this is the one: http://store.summitracing.com/default.a ... M%2D239421

With only a 1/2" thick bracket, the only orientation you can put the throttle body in is the way I have it, otherwise the dark goldish halfmoon linkage attached to the throttle shaft will hit the manifold.

No playdough handy, sorry.
Author:  FrankRaso [ Wed Sep 29, 2004 8:27 pm ]
Post subject: 
Thanks for making all those measurements.

* About the height of the adapter above the intake. I should have asked for the mininum height as I know it varies. Sorry.

* Did the goldfish-shaped part come with the Lokar kit or with the Howell kit? I am looking at my junkyard throttle body and the throttle lever doesn't look like yours. Also, it hangs 1" below the bottom of the throttle body. How low is yours?

* Would you still have the original 2bbl or 4bbl adapter for your intake? You could measure it instead of the gasket.

Frank
Author:  Pierre [ Wed Sep 29, 2004 10:13 pm ]
Post subject: 
The goldfish part is not part of the lokar kit. It came attached to the throttle body, a stock GM part. I wasn't aware there were different linkage attachments. I think the throttle body part# is off an early 90's truck, so the linkage would be for that as well.

I have the original adapter, but problem is I don't know where it is. But I do know it is in the same place as the used gasket I'm looking for, so if I find one I'll find the other ;) I'll look for it and get the last minimum measurment for you off the intake as well.

Just an fyi, The outside edge of the barrels don't fall 100% within the plenum. I mean, if you open up the throttle all the way, you can see the sealing edge on both bores, maybe 1/8-3/16" ? That's the problem on the side with the divit, because the divit combined with the large barrel makes the sealing surface there a bit larger then a 1/16th.
Author:  ShivaDart [ Thu Mar 03, 2005 10:24 pm ]
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Does FrankRaso still make these adapters, I tried to contact him and his email doesn't work. Anyone know where I could get a Rochester TBI to offy manifold adapter, I tried my hand at making one and it looks pretty sloppy. If I can't find something I might try again using steel.
Author:  sandy in BC [ Fri Mar 04, 2005 7:26 am ]
Post subject: 
Try Turbo City . I have a TBI to carb adapter on a Performer intake and it was a nice piece of work,,,,cheap too. They have a section call "TBI Specialties" or some such...fast shipper,,,,good stuff. They have a lot of TBI adapters and electrical goodies for swapping.
Author:  FrankRaso [ Fri Mar 04, 2005 12:06 pm ]
Post subject: 
I just noticed that there was another posting on this topic and I'm surprised that you weren't able to reach me by email. Try to use the forum's PM feature if my email doesn't work
Author:  ShivaDart [ Fri Mar 04, 2005 11:01 pm ]
Post subject: 
Thanks for the Turbo City idea, I checked that out and that adapter is exactly what I need.

FrankRaso, are you sure you have the link on your site set up, I don't remember much from my HTML days but it seems like you have the email tags setup up wrong, when I tried to email you in the send box I got a message saying "mail to Frank Raso", it seems like it should have your email address in it.
Author:  FrankRaso [ Sat Mar 05, 2005 7:41 am ]
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If you clicked on my email address at the bottom of a page, it would show as fraso AT mergetel.com. I was hoping that anyone doing so would change the AT to a @. I did this try to minimise spam. I am now looking into getting my own domain that supports FrontPage extensions so I can make a better web site.
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