3-1brl intake

[Anonymous]

hello

Im new here to the forum. Seems like alot of knowledge here hope you can give me a little advice on my project. Im building a 250 , i found a complete 3 carb intake manifold (offenhauser) ,it has 3 ibrls 2 holleys and 1 motorcraft . I also have hooker super comp headers for this set up. I plan on running a T-5 behind this in a 69 mustang coupe. What trans does everybody run? 4cyl. or V-8? Any help advise you can give me on this set-up would be greatly appreciated. Im especially looking to talk to people currently running a 3 carb set-up. Just came back from the 40th ann mustang show in Nashville and only seen 3 cars running anything other than stock , 1 with a 3 carb and 2 with 2 brl conversion.

 

[barroom hero]

from what ive seen, the 4cyl seems to be a fine choice because it has a better 1st gear ratio, but quite a few people seem to use the 8cyl. ive read about using an 8cyl and just changing the ratio on first. one plus to the 4cyl is that you should be able to find them easier. there are alot of posts on here on this topic, just search for it and there should be lots of help.

http://fordsix.com/forum/viewtopic.php?t=9708&highlight=summit+ram thats one post i have saved on the t5. hope it helped.

 

[CobraSix]

I ran the OFfy for a while until going to the aussie head.

I would get 3 identical carbs, otherwise syncronizing can be interesting.

The offy is a nice mod, definitely a show stopper. It does require patience and some fairly regular tuning to keep it running perfect.

Slade

 

[CZLN6]

Howdy Mark and All:

For a T5, consider your vehicle. A large/heavy car, with a relatively small/less torque engine with a high rear gear ratio, 3.25:1 or higher would benefit from the lower geared 1st & 2nd of the four cylinder T5. A lighter car with a larger, torquier engine, like a 250 and 3.25:1 or lower rear gear would do great with a V8 T5.

Make sure you match the input shaft to flywheel bushing to the trans you choose.

Check the chamber volume on the head you've found to determine your CR with your 250. Many of these 3 x 1 conversions were done on small chamber heads and are not suitable for use on a 250 because of high CR.

I'd start with the carbs that are on it, if they are in good shape. Slade makes a good point about trying to syncronize different carbs, but, in reality, you will be tuning the center carb as if it were a single, with choke, and at an idle. The end carbs will only be used past part throttle. That's assuming the set-up has progressive linkage.

It sounds like a great project.

Enjoy the trip.

Adios, David

 

[I66coupe]

Did you get the entire head with the Offy, or just the manifold plate and carbs?

Some of these Offys were made for the later, more square shaped intake log and some were for the earlier, more round intake. If you got just the manifold plate and carbs, you will need to find out which Offy you have to be sure it'll fit your engine's intake log.

Also consider a cam change to take full advantage of the new intake and exhaust capabilities.