offy tri-power ?

[Gene 64 2dr]

I just got my offy manifold and have a question on what carbs to use. The manifold is the later one that I'm putting on a "69" flat log head.
I've seen setups on the older manifold using three 1100's. The instructions say to use the stock carb for the center and use holley #1921-S or #2227-1A's on the ends.
The center hole opening is 1 3/4" and the ends have a 1 1/2" openings tapered down to 1 1/8". The bolt spacing is 2 5/8" on all three.
I know the earlier heads had a 1 1/2" opening so I don't think there shouldn't be a fit problem.
Are there any diferences in these carbs that should make a difference?

Gene

 

[CZLN6]

Howdy Gene;

I'm not familiar with those Holley #, but I'm guessing they are the list numbers for the early #1904, #1908 AND #1909 GLASS BOwLED ONE BARREL CArbs from 1960, '61 and '62.

Early Autolite 1100s from '63 170s and Fairlane 200, and later 200 to '68 all have the smaller throttle bores of 1.5"- actually 1 7/16th of an inch. many on this forum have used three 1100s

All of these carbs are encumbered with Spark Control Valves for the Load-a-matic distributor. What do the directions say about dealing with that?

Adios, David

 

[Javabean]

Unfortunatley the directions leave a lot to be desired on this setup. Couldn't you plug the spark control valves on the outer carbs? The SCV is more for the distributor than the carb operations correct?

A word of advice if you choose to use 1100s on the later model Offy. Try to find an 1100 from '63 - '64 with a manual choke for at least the center carb. The Offy for the later heads is not as long as the one for the earlier heads and the auto choke will stick out too far, making it impossible to fit the rear carb. At least from my experience that is, I haven't read anyone else posting about this issue but I know I ran into it when doing a mock up assembly on my bench.

Good luck,
Jay

 

[Gene 64 2dr]

Thanks for the replys. Your right about the instructions, it looks like they were printed 30 yrs ago and yes there not the greatest. But then again I've never been very good with instructions anyway.

They don't say anything about how to set up the distributor. I'm planning on upgrading mine and I guess I'll deal with that later unless anyone has any input on that subject now.

As far as the carbs being closer together I noticed that they were closer together than the older one and might be a problem. The pics I've seen with the older manifold puts the outer carbs pretty much in the middle of the outer to intakes where as the newer one puts the carbs almost in line with #2 and #5. I'm going to try to fine a carb wth a manual coke but if need be I'll just remove the chokes. I'ts not going to be a daily driver anyway and won't be driven in the winter so I don't yhink I'll have to much of a problem there.

If anyone would want some pics of the newer one let me know. So far I've only got as far as grinding the ends flat and yet to drill the holes.

Gene