Thought this might help those 5speed VE guys. Someone correct me if Im wrong?

1st= 3.285
2nd= 1.850
3rd= 1.272
4th= 0.954
5th= 0.795
Reverse= 3.429
Final Drive Ratio= 3.823

MPH=(engine RPM X Tire Radius) / (Final Gear Ratio X 168)

Engine rpm =6,550rpms

Tire Radius (inches): aspect ratio(205 X .65=133.25)X .0394 (mm to inch conv.) = 5.25in
5.25 + 15(rim size) X .5
5.25 + 7.5=12.75

Final Gear Ratio: gear ratio (3.285=1st gear) X final drive (3.823)=
12.558555

MPH = (6,550 x 12.75) / (12.558555 X 168)

MPH = 83512.5 / 2109.83724

MPH=39.58mph@6,550rpm in 1st gear

MPH/RPM= MPH / (rpm /1000)(about 6.04mph/1,000rpm)

Taking that same equation and use that for 2nd gear

MPH = 83512.5 / 1.85 X 3.823 X 168

MPH = 83512.5 / 1188.1884

MPH = 70.29mph@6,550rpm in 2nd gear(about 10.73mph / 1,000rpm)

Again for 3rd gear

MPH = 83512.5 / 1.272 X 3.823 X 168

MPH = 83512.5 / 816.959808

MPH = 102.22mph@6,550rpm(about 15.61mph / 1,000rpm)

4th gear

MPH = 83512.5 / .954 X 3.823 X 168

MPH = 83512.5 / 612.719856

MPH = 135.30mph@6,550rpm(about 20.66mph / 1,000rpm)

5th gear

MPH = 83512.5 / .795 X 3.823 X 168

MPH = 83512.5 / 510.59988

MPH = 163.56mph@6,550rpm(about 24.97mph / 1,000rpm)

Reverse

MPH=83512.5 / 3.429 X 3.823 X 168

MPH=83512.5 / 2202.323256

MPH = 37.92mph@6,550rpm(5.79mph / 1,000rpm)

 

RPM* =\


123

 

* = multiply ?

= \ ?

6,550 * = \

 

how long did you spend doing this? or did you find it somewhere?

 

This should stop all the how fast can I go threads. lol (My first post) Dude you must've been bored or found some internet calculator. Can you do this for the VG's also. The max speed should be around One Fitty.

 

but it doesn't take into account wind resistance which is the reason why you need more horsepower to go faster, not just RPMs

 

Ill do a search on VG auto VE auto VG 5speed gear ratio's and do them. It really didn't take me that long.

All I had to do was figure out Part A which would be a constant since overall tire diameter and rpm would not change in the equation and divided by Part B, which does change.

Keep in mind this is just the top speed in each gear, it does not mean you car will reach those speeds in 5th gear, or even 4th gear (for you VG guys )

Another purpose for this math is knowing how many MPH/1,000rpm. This could possible help you rev match down into whatever gear you choose to select. Not only that, but it could prevent you from dropping into a gear too low for certain conditions and overshoot your powerband, or worst, overshoot your rev limiter and blow up your engine. I could calculate optimal shift points since I know how many RPM each gear drops, but I would rather do it according to gear ratio's. More to come I guess? No Im not bored, I just found the need to contribute something useful every once in awhile.

 

It is RPM, not RPMs/RPM's/RPMS/anything with an S.

Just trying to save James/Michael/Randy/Mike/etc a big headache

 

corrected

 

http://www.geocities.com/z_design_st...nsmission.html

 

Thats the easy way out

 

VG auto's

Gear Ratio's
1st = 2.785
2nd = 1.545
3rd = 1.000
4th = 0.695
Reverse = 2.272
Final drive ratio = 3.642


MPH=(5,950rpm X 12.75) / (2.785 X 3.642 X 168)

MPH= 75862.5 / 1704.01896

MPH= 44.52mph@5,950rpm in 1st gear
MPH/1,000rpm= 7.48mph

MPH= 75862.5 / (1.545 X 3.642 X 168)

MPH= 75862.5 / 945.31752

MPH=80.25mph@5,950rpm in 2nd gear
MPH/1,000rpm=13.49mph

MPH=75862.5 / (1.00 X 3.642 X 168)

MPH=75862.5 / 611.856

MPH=123.99mph@5,950rpm in 3rd gear**
MPH/1,000rpm=20.84

MPH=75862.5 / (.695 X 3.642 X 168)

MPH=75862.5 / 425.24

MPH=178.40mph@5,950rpm in 4th gear ***
MPH/1,000rpm=29.98mph


**Does not take into account T/C lock-up
***DOES NOT MEAN YOU CAN REACH THEORETICAL TOP SPEED IN THIS GEAR

For the love of human-kind, don't try this on a public road

 

You know Revolutions Per Minutes S

 

what are the gear ratios for the VG 5-speed?

 

Gear Ratios:
1st= 3.285
2nd= 1.850
3rd= 1.272
4th= 0.954
5th= 0.795
Reverse= 3.429
Final Drive Ratio= 3.650

I worship the person who wrote this page http://www.geocities.com/jgadlage/maxspecs.html

Its hard to find 3rd gen specs

 

VG 5-speed @ 6,000 rpm:

1st - 38 mph
2nd - 67 mph
3rd - 98 mph
4th - 131 mph
5th - 157 mph

@ 7,000 rpm:

1st - 44 mph
2nd - 79 mph
3rd - 114 mph
4th - 152 mph
5th - 183 mph

60 mph @ 2,300 rpm in 5th
75 mph @ 2,875 rpm in 5th

 

As if a VG can go that fast

 

well... with just an intake and exhaust mine sure acted like it would top out 5th but i had no idea how fast i was going since i pegged the speedo in 4th and went a bit more, then shifted to 5th and had an extra 1,000 rpm. it kept climbing but so did my heart rate (my stupidity went down though) so i just stopped it there. with the turbo... the thing pulls insanely well in 5th. when passing people i constantly have to keep myself from going well over 100 in just a few seconds. with a bad exhaust leak, ****ty intake and exhaust, and low boost i couldn't imagine fixing all that and having even more power. i can't wait!

(note: said speeds were attempted on a race track)

 

major

 

hmm, I couldn't try for the life in me to reach 39mph in 1st gear. Indicated, it was about 37mph which would mean 6,100-6,200rpm bumping against the rev limiter. Second gear seems to be pretty darn accurate. I would rather not try out 3rd and 4th gear on public roads

 

now heres a question

heres the specs for a 2nd gen 5spd

Gear Ratio...............Transaxle Model...RS5F50A

1st 3.285
2nd 1.850
3rd 1.206
4th 0.911
5th 0.740
Rev. 3.428

Final Gear Ratio.......................3.429

Now all of the above is from the factory service manual...1986


do ya think the 5th gear and final drive from a second gen could be swaped into the VEs vlsd RE5F50V

if so it would help with the useless 1st in NA mode and usless 2nd and somtimes 3rd in power mode plus it would lower the 4krpms while crusing at 100mph BS

i alreaddy have the gutts of a 2nd gen 5spd in a box in my basement and 2 spare vlsds that need some attention

 

with that 86 gear box you'd have:

1st - 41 mph
2nd - 72 mph
3rd - 110 mph
4th - 146 mph
5th - 179 mph

100 mph would be 3,350 rpm in 5th

60 mph @ 2,000 rpm in 5th
75 mph @ 2,500 rpm in 5th

I think that'd actually hurt mileage a little bit since that's a bit below the peak torque on our engines (VG at least).

To really maximize fuel economy on the VG with that gear box you'd have to do ~84 mph.

 

are those mph numbers with the VG or VE redline

if for VG could you calculate for the VE with 7200rpm redline