Yenko turbo 400 speedo adaptor

JBB · #1 03-02-2003, 03:00 PM

You are right Joe, it is to give the proper speed on the speedometer. But the only way to achieve this is the use of the Stewart Warner unit, as a 4.10 or bigger speedo gear could not fit in the casing. This info is per a transmisssion specialist, who has been rebuilding transmissions since the early 60's............

**copo69** · #2 03-04-2003, 02:53 AM

Well, do all 4:10 or lower geared cars use adaptors or only 14" tired cars? Auto's different from 4 speeds?

**COPO** · #3 03-04-2003, 11:36 AM

Believe it is all 4.10 and greater got the adapter regardless of trans type. My 70 Z-28 w/4.10 also has the adapter and it came with 15" wheels.

**Kurt S** · #4 03-05-2003, 03:05 AM

No, not all Muncies hooked to a 4.10 got the adaptor. Depended on which Muncie model it was, there were two different size speedo drive gears.

**copo69** · #5 03-05-2003, 12:53 PM

Should the 9737 Camaro with 4 speed have the adapter? 9737 with auto?

Ed Cunneen · #6 03-07-2003, 03:38 PM

Yes

Unreal · #7 03-08-2003, 12:06 PM

Is this the little 90 degree adapter that shows on the AIM? I have one, but was not sure if I should be using it.

**Kurt S** · #8 03-09-2003, 05:21 AM

[ QUOTE ]
Should the 9737 Camaro with 4 speed have the adapter?

[/ QUOTE ]
Maybe. Some 4.10 rears got them, some didn't. Depended on plant inventory. I have documentation on several Z's with 4.10's and no adapter. Tire size shouldn't be a factor, but Z's had 15x7's anyway.

JBB · #9 03-09-2003, 05:55 AM

This part:
Stewart Warner
GGGF X1 (or 666F X1)
1.300 J
Is specific to a solid lifter L-78,L-89,4.10 or higher w/TH400.
It is manditory for a COPO L-72 or ZL-1 w/TH400 in leiu of the fact a 4.10 was standard rear,with higher gears optional. I am not sure of the M-22 or M-21 4 speed application............

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