stall convertor

[convertable67]

My 67 convertable  runs a 302c with c4 with shift kit fitted, 4bbl manifold with 475 holley elecronic dissie, goes well when its rolling  but doesnt get off line quick enuff to threaten hyundies or kias. ( i rely on the looks and note to   bluff them)It has been suggested i put a higer stall convertor (3500) in it to get the revs  at low speed. i dont know much about this so any thoughts would be apprecitated,  What difference would i notice as far as driving?? fuel is not an issue

[nassi]

Since fuel isnt an issue, have you considered another diff ratio?
nassi

[convertable67]

i briefly thought about it but dismissed it for some reason i cant remember, I have a 8 3/4 diff which i think is 3.5 ratio from memory on the data plate, I seem to remember it wasnt as str8 foward as a 9 inch ratio change  due to axles splines or something ,but will look into it again ,thanks for jogging my memory it may be a better cheaper option

[66ccode]

If you have a 3.5:1 you shouldnt have any problems leaving most cars behind at the lights. I think you probably have the 2.8:1. You can add a stall converter to bring your engine up into it's power band, however a stall converter combined with a tall diff ratio (such as the 2.8) is not particularly driver friendly. At speeds below 100, even when just accelerating lightly (ie from 70 to 80) the engine tends to rev up to the stall speed, which can become very tiresome, especially if you experience some exhaust drone.
I would recommend you check your diff ratio, and if it is  a 2.8, go down the path of a ratio change (3.25 or 3.5), and then if still not happy, perhaps a mild stall converter.

[2233]

Nassi and 66 are spot on the money.:(

Diff ratio best bang for buck.

3500 stall in a 302?? It must be a decent engine to run that much stall.

It would/will drive you bonkers !

[convertable67]

have spoke to local diff guy who  thinks 3.75  or 3.9 would make it launch  a lot better. He also thinks stall conv will be a pain to drive, He suggested i shop around for  parts maybe even USA  to save money as local  8/ 3/4 are hard to  find   nowdays, any links etc would be apprecitated

[convertable67]

update >> 66ccode  was spot on ,  I decoded the data plate and it comes up as a 2.8.1 ( never trust a expert with a beer  in his hand) Not that a lot changes but i will be looking for 3.5.1 or a tad lower now, still need to find the bits

[2233]

I was running 4.1's with a std 289 and a c4.

Sensational on launch, but hell on the freeway. 3500rpms at 65mph with 235/60/14's :*

3.7 or 3.9's will will be a little less painfull but still too much.

3.5's maximum unless you have a o/d.

[HEVEN67]

Try a trans lock! I heard thay are tric and you can cruise just jike standard!!!