What would be the differences on a carb designated for an automatic and one thats made for a manual transmission? Thanks

What would be the differences on a carb designated for an automatic and one thats made for a manual transmission? Thanks

There can be many differences. Some which may or may not be present:

(A) As a general rule, a carburetor for an automatic transmission is calibrated 1/2 size to 1 full size richer to compensate for losses in the fluid coupling. Hence lower fuel economy on vehicles with automatic transmissions.

(B) The presence of a "dashpot" (slow closing throttle control valve).

(C) The presence of a "hot idle compensation" valve.

(D) Vacuum ports for the distributor may be ported or non-ported.

(E) Throttle linkage may be different.

(F) A vacuum port may be present for transmission control.

These are general answers to a general question. Best to always know what characteristics are possessed by the correct carburtor, and then compare these to the characteristics of a different carburetor that you may wish to utilize.

Jon.

Thanks Jon, yes very general question.. Specifically I have a 17057202 Qjet on the car right now. Consulting one site that matches the car to carbs that will or should fit states that a 17057203 or 7204 would also be appropriate. The 7203 is for a manual tranny and I have a chance at getting one dirt cheap so I just wanted to make sure that it would suit my needs. Thanks for your time.

As a general rule (remember that generals make rules to be broken by us lower ranking personnel http://forums.performanceyears.com/g.../icon_wink.gif) carburetors designed for use with standard transmissions will have idle issues if placed on the identical engine with an automatic transmission (see "A" in my previous post); however, with your 1705 prefix, you are newer than my area of expertise.

Jon.

LOL I hear you, I figure it couldnt be any worse than what I have on there now and the way it idles. Thing needs a rebuild so bad its not funny. I ll probably try and get the 2 of them, practically being given to me anyways. Its only to put a carb on so I can rebuild the one on there at the moment.. Figure I ll give a rebuild on my own, if it doesnt work out right. Theres a place in Toronto that will rebuild it totally for 195 cdn including the recoloring and re-bushing.