CARB PROBLEMS--67 MUSTANG with 76 250

[Anonymous]

Greetings Ford six enthusiasts,

We're running a '76 250 from a Granada in our '67 Mustang. The 250 has a Carter RBS (the way it came) that I beleive inhibits performance rather than promoting it. I'd like to switch to the Autolite 1101 like the earlier 250s from '69 to '70whenever.

I can't seem to find the spacer block that fits on top of the manifold part of the head. The block for the Carter is 2 3/4" between carb-mounting studs while I believe the Autolite 1101 requires a 3 5/8" gap between studs. Any help out there?

Any suggestions? Any other carbs that'll work? I don't really want to switch heads.

Thanks,
Rich

 

[CobraSix]

Rich,

Why not do this if you want to wake up the engine some. Buy a 2V adaptor from cliffordperformance.com or stovebolt.com. Then stick a Holley 350CFM 2v on top of it. Your 250 will love you for it.

Welcome to FSP.

Slade

 

[CZLN6]

Howdy Rich:

The Autolite 1101, rated at 210 cfm, was used on the 250 engines in the '69 model year only. After that the Carter RBS, rated at 215 cfm, was used til about '75. Sometime during the '75 model year a version of the Carter YF, rated at 195 cfm. All carbs had strengths and weakness. All are susceptible to degraded performance due to dirt, crude, wear and heat. All are easily rebuilt and kits are available and relatively cheap. All suffered from a weak, and too small accelerator pump system. Each succession was 'sposed to be an improvement over the previous. Most noticeable is the YF for improved idle transition and better economy with a slight loss in WOT on the top end.

All in all, I think I'd stay with the RBS. On the 1101, If you can't find an adaptor you can easily make one out of a flat piece of 1/2" aluminum. You can also slot the mounting holes in the carb base to accomodate a different bolt pattern. If you switch to the 1101 be sure to get the appropriate air cleaner base as it will be different that the RBS.

Also make sure you ignitions system is not the cause of "Carb problems".

Slades suggestion is also a good one, but an adaptor will lessen already tight hood clearance. If you're going the two barrel route plan to modify a head for direct mounting to the log.

Adios, David