1227749 Service number?

[Scot Sealander]

Ludis Langens wrote:

> Doesn't seem to be.  1228707 was used with Q4's 1989-91.  1228708 is the
> underhood version (1990-91).
>
> What's inside the 8707?

The usual.  Very similar to the 1227749, less the A/D mux.  Some kind of small
SOIC added to the fuel logic.  Never did fire up the 'scope to see what it did.
Perhaps true alternating fuel firing....  like TBI.

>  Is it a different PCB?

Yes. 79A433

>  Perhaps a differently populated 730/749?

 No, not directly.  Just similar.

>  Perhaps the 8707 adds the quad driver back in.

No.  Still has the location unpopulated.

> I've only ever seen two Q4's in the junk yard, and they were both 88's
> with 749's.

I have seen a lot of them here....  Seem to have two different intake manifolds.
One almost looks like a set of headers, the other is more like a common plenum.
I really don't know anything about them though.

The tables are also set up to handle higher RPMs than the usual GM stuff.

Scot Sealander   Sealand @ clarityconnect.com