Quote:
Originally Posted by GregWeld
Not to cast any "dispersions" on your builder - but you don't turn a transmission into an over drive by changing out the rear end gears.... The Richmond 5 speeds that I know of - had 1:1 final drive ratios... THAT is not an overdrive... an overdrive has something LESS than a 1:1 ratio -- more like .70:1 or .49:1
What he's trying to say is that you could have acceptable highway cruising RPMS by changing the rear end ratio to the 3:23 or 3:08 gears... but that is not what you'd do if you want some performance AND acceptable highway RPMs... if you want that combo -- you need to buy a REAL OVERDRIVE transmission such as a Tremec 5 or 6 speed. Also note that with the Tremecs, you can place the gear shift in different locations.
Check out Keisler Transmission for some information on this kind of stuff. Placement of shifter and gear ratios etc and how they affect cruise rpms etc.
http://www.keislerauto.com/ |
The early plan for the '69 Firebird is to have an engine putting out maybe around 550 to 650 hp with high Pontiac torque. If I remember correctly (and I am probably saying this wrong) my builder said with this type of hp I may not like taking off in first gear or taking off in first gear would be difficult. That it would be difficult to drive in bumper to bumper traffic. This is why he likes the Richmond 5-Speed with the high hp application.
Like I said earlier, I am no gear head so please keep the info coming.
Thanks.