Has anyone swapped out the lower gear ratio 1-2 gears in a 904 trans? Hhow far apart do you have to take the transmission? Any special things to look for?
Thanks
Thanks
The low gear set came in later transmissions like a 998/999, and you will need to get deep into the trans to do it.
you will need to remove the front pump...the two clutch pacs . Then you will see what is called the drivetrain portion of the trans...that is where you change out the gear ratio....not hard...just make sure you have all the pieces that go tomorrow with the lower gear set.
Trying to keep it as stock as i can. Within reasonWhy wouldn't you just use the entire trans, case and all, I did.
How about low compression 273? If it can have a bit more get off the line id be happy espically with a highway ratio rear.
AJ/FormS
I wish I knew 1/2 of what you do. Thanks for the info. A TC would be much easier to do than the gears. The reason I am inquiring about gears is I'm in the process of building an 8 3/4 and could stay with the ~2.94 highway gears or step up one notch to ~3.23. So before I commit on a rear gear ratio (stock tire / wheel size) I figured I would investigate the other options. I have no plans to build out the engine, just want to be able to spin the tires without turning a corner on occasion. ;^) cheap thrills from a 51 year old daily driver.
You lost me hereIf you had the 2.74 low gear and the stock TC, you would have 105x2.74x2.94=846#
It would take 1476/105=a 14.06 starter gear to equal what the TC can do. This would be 14.06/2.74=5.13 rear gears with the A998.
You lost me here
Thanks for the clarification. crystal clear. Thanks
So what you are saying is now I just need a roots blower and some nitro-methane! (just kidding)
Have a good one
You believe there is 20 hp difference between a stock LOW compression 318 and a stock HIGH compression 318?? Sorry, I ain't buying it. There isn't but about half a point of difference in compression on any of them.Etor
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Here's the deal tho; the 318 has a pretty flat torque curve between 2500 and 3000. Imagine it makes 200ftlbs all the way. At 2500 this is 95hp. at 3000 this is 114. So that's 19hp between the marks.
If your 72 is the Hi-Compression model, imagine it makes 250ftlbs, then the numbers are 119 and 143hp; this is now a 24hp difference. These are maximums at WOT. You can of course get your 318 to deliver less than the maximum by not flooring it.lol.
At 65mph, your rpm might be about 3300, so either TC will be fine. It looks like a city car, so if I had only the two choices of 2500 and 3000 I would choose 3000,lol. but I really liked the 2800 with the 4bbl-low-C teener and about the same starter gear that you have.I'm at 3650 car and driver