hey guys i ve been seaching here for like 2 hrs and cant seem to find a straight answer.

i have a 700r4 trans with 2.73 right now, i recently picked up a 9 bolt with 3.27 my question is what color drive and driven gears do i need, i was going to get a rear with 3.42 so i had bought a yellow driven and grey drive, upon some research i have found that i do not want to pull the tail shaft out right now, so can i just use the yellow driven gear, with the original drive gear in there right now? would that alone put me closer to my actual speed? also i read that if you use a 40 tooth driven gear you need a new housing is that true.


thanks

 

anybody

 

I found a chart someone made in a thread on here that will help you out. If I had a link to it, I would post it ... but fishing through some posts after a search should give you some results. That's how I figured mine out. Good luck!

 

Post your rear tire size, then I'll post you the GM part numbers.

 

295 35 18

 

THis site can help you: http://chevelleengineer.home.comcast...eer/speedo.htm

 

You have 2 choices. First, and more accurate, is to buy the red 17 tooth drive gear GM part number 8640517, and a purple 43 tooth driven gear, part number for cable speedometer is 1362196, for the later style it's 25513050. The other choice is the gray 15 tooth drive gear, PN 8642620, with the blue 38 tooth driven gear, PN 1359272 for cable or 25513045 for the other style.

 

wow thanks for the help i was just looking for the colors, but the part number to is awsome info thanks alot man