Finding the best ratio (cross posted in Off Road as well)

Bob Ingman · Post by **Bob Ingman** » Mon Feb 09, 2004 10:07 am

Randy I have noticed that when looking at ads in HVWs for trans rebuilders the pyramid is the one most often displayed. Take a look and you`ll see it. BOL. Bob Ingman

Mattt · Post by **Mattt** » Mon Feb 09, 2004 11:34 am

Bob Ingman wrote:Mattt you`re rirght about the 02s (72-73 1/2 3 rib). There were some 5 rib 02s w/5.37( 73 1/2-74) and some pryamid five rib in 75 with 4.86. By 76 we had the 091 6 rib. The pyramid case is sought after by rebuilders as the base for high performance transaxles. I`m using a T-1 starter on mine bit its the auto stick/thing variety without the pilot after the gear.
Last year Vince had a Thing transaxle freshly rebuilt and never installed that had a 4.37 R&P in it . It was available for $275 at that time. I do not know if Mike aquired it or not but if so would be a real good candidate for all round trans. Best of luck. Bob Ingman

All of the 73-74 002s I have seen were a 3 rib case. I had in the past a '75 5 rib 002 with 5.43 gearing. I called a tranny shop about it and they said it was an optional gear set that was put in at a later date. According to them all 5 rib bus trans came with the 4.86 ratio(7/34 teeth count) from the factory. The tooth count on the 5.43 Pyramid was 7/38.

Bob, what is it about the Pyramid 002 that makes it more desirable to high performance builders than an 091?

thats the same starter Im using on mine, the Thing/Auto stick self supported starter.

Mattt · Post by **Mattt** » Mon Feb 09, 2004 11:37 am

Kurt wrote:Bob,
Are all 5 rib trannys the same, or is it just the '75 model that is sought after?
Kurt

The Pyramid 5 rib trans was only available in 1975. No other year bus had a 5 rib case. Maybe, just maybe a very late 74 would, but thats esseentially a 75.

3 rib bus trans case 68-74
5 rib " " " 1975 ONLY
6 rib " " " 76-79

Bob Ingman · Post by **Bob Ingman** » Mon Feb 09, 2004 12:48 pm

Matt am i mistaken in that there are five rib and five rib pyramid configurations. If so sorry to spread bad info here. Best of luck. Bob Ingman

Mattt · Post by **Mattt** » Mon Feb 09, 2004 3:21 pm

Bob Ingman wrote:Matt am i mistaken in that there are five rib and five rib pyramid configurations. If so sorry to spread bad info here. Best of luck. Bob Ingman

To the best of my knowledge, there is only 1 5 rib trans. Some people call it a pyramid trans because thats the shape that the 5 ribs form. In any case, its all the same trans. A 1975 bus trans IRS.

5 ribs, the top two of which are shorter, so it looks like the 5 ribs form the shape of a pyramid.

Bob Ingman · Post by **Bob Ingman** » Mon Feb 09, 2004 3:23 pm

Thanks matt for clearing that up for me. I thought there was a 5-rib like the 3&6 rib and a 5-rib pyramid. Best of luck. Bob Ingman

Mattt · Post by **Mattt** » Mon Feb 09, 2004 3:27 pm

Bob Ingman wrote:Thanks matt for clearing that up for me. I thought there was a 5-rib like the 3&6 rib and a 5-rib pyramid. Best of luck. Bob Ingman

Not to say it doesnt exist, but Ive never seen one as you describe.