Thread: Best tranny setup for FI..

Dre,

This conversation kinda got off topic a little bit. What I'm working with is a B15 SE 5spd LSD tranny, and my 98 SE-R 5spd tranny. Why would I buy another tranny when I would have these two?

As an aside, please provide me with the SR16VE/20VE/Etc 5spd gear ratios and FD ratios when you get around to it. I would like to add it to the worksheet so that all possible trannies for the FWD SR are listed. I can add the 6spd later on down the line.

V- I've got the file ready to go, just going to lock it down a little bit so that the user doesn't accidentally mess up the formulas.

Let me know if you want me to send it directly to you or if I should just upload it to a fileshare service.

There's only one thing I haven't quite figured out:

The Tire RPM/MPH Ratio. I'm not quite sure what the formula should be, because I'm not sure what exactly the old spreadsheet I've been looking at, is referring to. Could it be that this calculates the RPM/MPH correction given changing of the tire size? If so, I'm going to have to create some hidden cells that refer to the "OEM" tire size, so that when the user changes the blue cell he/she actually gets a correction factor in that Tire RPM/MPH Ratio block.

If you have the B15 trans, you could get the P11 gearstacks from a QG18 tranny, along with your 4.176FD, and swap the 5th gear over from the B15 SR stack to the QG stack. That would be cheap. Just make sure you use the QG stack with the 4.176FD or it won't work out very well.

With this, you will basically have a P11 tranny, but with a longer 5th gear for freeway cruising.

As Dre stated above, why would I get the entire stack from a P11? The only difference between a P11 and B15 gearstack is 5th gear and the FD.

Since I have a 98 tranny, the only thing I need to do is pull the FD from it and slap it into the B15 tranny. 5th gear on a B15 tranny is shorter than a 5th gear from a P11 or from my 98 tranny.

This is the break down with 4.176 FD from a 98 tranny given OEM tires on a 98 SE-R:

Gear: Ratio - MPH @ 8000RPM
1st: 3.063 - 43.61
2nd: 1.826 - 73.16
3rd: 1.286 - 103.88
4th: 0.975 - 137.01
5th: 0.756 - 176.71 - At 3000RPM in 5th - 66MPH.

B15 breakdown given 4.437 FD and OEM tires on 2000 SE:
1st: 3.333 - 38.96
2nd: 1.955 - 66.43
3rd: 1.286 - 100.98
4th: 0.926 - 140.24
5th: 0.733 - 177.16 - At 3000RPM in 5th - 66MPH.

Now, changing ONLY the final drive out on the B15 from the 4.4 to the 4.1 yields the following:
1st: 41mph
2nd: 71mph
3rd: 107mph
4th: 149mph
5th: 188mph - At 3000RPM in 5th - 71MPH.

IMO, this is by far better for a mid-frame turbo setup such as mine for highway and daily driving. I don't believe this will be beneficial for those of you running 1/4mi. tracks, since with a mid frame turbo and supporting mods, you'll end up shifting into 4th just before crossing the 1320.

Update: Vadim was nice enough to help me upload the file to my first post, so that all can grab the excel spreadsheet and use it.

Thanks V!!!

so does the b15 qr18 trans have the b15 5th gear. If so im definetly gonna put a trans together using that box.

Not sure, look in the fsm and see what the gear ratio is. They're saying the stack is identical so I don't see how it'd be different?

The only part you can use from the 98 trany is the Differential because the output shaft its not interchangeable with the B15 P11 trany you still need the output shaft from the P11 and swap all the gears from the B15 output shaft.. Remember the FD consist of 2 parts output shaft and ring gear..

Ah thank you for posting that. I'm just now starting to get into the whole transmission side of the house. I feel comfortable enough with the motor side, so I'm now expanding into other important issues

So then I need the FD from the P11. What about a FD from the P10? Or is the output shaft identical to the B13/B14 tranny?