Hey, I have an '84 Z28 w/ a regular (AFAIK) 700R4 tranny and 3.23 gears (changing soon .. anyway, prior to swapping out the 305 and changing the rearend I also want to give it a little bit of a stall converter as well... ~2k or therebouts.. a bit over stock but not too much for daily driving.. but there's 1 problem.. apparently in 84 Chevy made 700R4s with both 27 and 30 splines (at least this particular vender has potential converters claiming to fit ~84 F-bodies with both 27 or 30 splines) so I'm wondering if there's an easy way to tell which I have so that I can get the right converter for it... Anyone know of a good way to find out how many splines will fit my particular tranny? I gather the best way is probably checking #s off the tranny itself but.. anything else?

 

As far as i'm am aware, Gm did not change the splines untill 88 or 89. I will bet you have a 700r4 with 27 spline tranny. S omeone correct me if I'm wrong.

 

I think you're right... I probably misunderstood the description for these particular converters.. they probably have a 27 for the 84-86 or whatever and 30 for the rest.. Good to know, thanks

 

In mid 1984 they went from 27 to 30 spline.

 

Yeah, I found that out after posting lol.. checked #s on the tranny though and couldnt really make anything specific out but the manufacture date on the driver side door says 09/83 so I assume this is an '83 tranny (unless its been changed, but I doubt it has..) so would I be correct in assuming I should be safe getting a 27 spline converter?

 

Actually, you need to find the code on the transmission because it may have been swapped. There should be a number stamped right above the pan, towards the rear on the passenger side of the tranny.

 

Hm. Agreed that's the safe way to go
Do you know offhand what kind of # is stamped there? like.. # of digits, etc.. it's supposed to signify the year of the tranny, right?

there was a 4 around there.. but nothing else..

 

It should have about 8 digits/characters. It will be a number, 3 letters, three numbers then one letter like this: 4YDM086C

 

Ok, if the first number happens to be a 4, this means the tranny is an 84 and probably has how many input shaft splines? 27/30?

Also, if you dont mind about converters.. assuming the tranny is probably an 84 would it make much difference getting a lockup or a non-lockup converter? (including whether itll fit/work .. Btw, I think this year involves the computer controlling certain (but not as much as newer ones..) aspects of the car.. would it normally effect shiftpoints or might changing the converter effect it at all? To illustrate the point, simply flipping the air filter cover over (to let it breathe more...) and flooring it yielded horrible performance (it would stumble ~the 1st-2nd shiftpoint.. which is somewhat high.. like 6-7k.. either possibly chipped(?) or a shiftkit.. its obviously carb'd) but immediately stopping and flipping the cover back around resolved it.. so, I just thought I'd check to see whether any other seemingly minor changes may adversely effect it

thanks a lot