3.73 Gears
6th Gear Member
Joined: Jun 2007
Posts: 16,182
From: PA to KY ('07) to IL ('09) to MS ('10) to FL ('11)
Stepping up to 3.73's from 3.31's will be worth it but not from 3.55's.
As far as your other mods, why the Steeda TB? Aftermarket TB's are useless for performance gains unless you intend to go FI. Plus, it's pretty ballsy to even ADMIT to having a TB spacer, let alone installing it. LOL!
As far as your other mods, why the Steeda TB? Aftermarket TB's are useless for performance gains unless you intend to go FI. Plus, it's pretty ballsy to even ADMIT to having a TB spacer, let alone installing it. LOL!
3rd Gear Member
Joined: Aug 2008
Posts: 761
From: Amarillo, TX
Stepping up to 3.73's from 3.31's will be worth it but not from 3.55's.
As far as your other mods, why the Steeda TB? Aftermarket TB's are useless for performance gains unless you intend to go FI. Plus, it's pretty ballsy to even ADMIT to having a TB spacer, let alone installing it. LOL!
As far as your other mods, why the Steeda TB? Aftermarket TB's are useless for performance gains unless you intend to go FI. Plus, it's pretty ballsy to even ADMIT to having a TB spacer, let alone installing it. LOL!
However, it seems he suffers from "Manufacture suggested power gains" syndrome. It's easy when you may not know much about what a part can do to a car. But according to a websites claims "OMFG! Bolt 55 RWHP with this part!!11!!one11 for cheap!" it can seem to be misleading. Anyways, I say scrap the TB spacer and get 4.10's.
4th Gear Member
Joined: Oct 2007
Posts: 1,778
From: Harrisburg PA
My gear history: bought the car with 3.55s. Installed the same BBK intake and a Brenspeed tune. Got caught up in all the "don't fear the grear" recommendations and had 4.10s installed. Install 1 = whine. Install 2 = whine. They finally got it right on # 3. At first I loved the 4.10s, it makes the car very snappy. But after a while that wore off and I started to miss first gear (its so low to be practically useless) Plus I got involved in AutoX and Track Days and found the 4.10s to be horrible - kept bouncing off the rev limiter. So one more install, 3.73s this time. Still there...for me they are the much better choice. YMMV.
5th Gear Member
Joined: Feb 2007
Posts: 2,211
From: Hawaii
go big or go home. you will really enjoy the 3.73 gears...but after a while you'll be wondering what 4.10 would be like
and finally, make sure you have good quality rubber out back...and at least a 275 width. my car came with 3.73 and I can light up my tires without even trying.
I'm running 275 out back. they are better than the 235 OEM's, but it still isn't much of a challenge to break them free.
other way around man
with a stick, you can slip the clutch a bit and don't need the deep gearing as much. rpm launches aren't an issue
with an auto, you need the deeper gears to offest the torque converter and it's losses at low RPM.
and like already mentioned, go with FRPP Gears. Ford makes some really good products. just avoid the FRPP motive gears. I believe they have a "M" on the end of the parts #. For some reason the Motive gears are noisy.
also, GEAR WHINE IS NOT ACCEPTABLE. It's indicative of a bad install, and/or shoddy parts.
also, GEAR WHINE IS NOT ACCEPTABLE. It's indicative of a bad install, and/or shoddy parts.
and finally, make sure you have good quality rubber out back...and at least a 275 width. my car came with 3.73 and I can light up my tires without even trying.
I'm running 275 out back. they are better than the 235 OEM's, but it still isn't much of a challenge to break them free.
with a stick, you can slip the clutch a bit and don't need the deep gearing as much. rpm launches aren't an issue
with an auto, you need the deeper gears to offest the torque converter and it's losses at low RPM.
6th Gear Member
Joined: Feb 2007
Posts: 7,635
From: state of confusion
OP - letting emotional statements like "don't fear the gear" or "go big or . . ." sway your choice is about the worst possible approach to choosing gears.
If you put a little thought into this, you're more apt to come out of it satisfied. A little "speeds in gears" math and deciding if you need to be in a certain gear (or avoiding upshifts) at particular speeds. Argonaut has given two of the more common situations where it is entirely possible to gear it too deep. There may be others.
If you "go big" for the right reasons - YOUR right reasons - that's fine.
Sorry. kings has it right.
The torque converter helps you off the line - it lets the engine slip up a bit and still multiplies the torque that's available there by almost 2. Stall ratios above 2 are possible, though I don't know if any are available for this tranny or whether they retain the lockup feature.
Slipping the clutch . . . if you really like to replace them frequently, it's one way to manage wheelspin. Pretty brutal though.
2nd and 3rd in the 5R55S AT are shorter than 2nd and 3rd in the TR3650 MT. So the AT needs LESS rear axle gear for those, not more.
At best, where the driving/racing uses 4th and 5th almost exclusively, the AT only needs the same gearing.
Norm
If you put a little thought into this, you're more apt to come out of it satisfied. A little "speeds in gears" math and deciding if you need to be in a certain gear (or avoiding upshifts) at particular speeds. Argonaut has given two of the more common situations where it is entirely possible to gear it too deep. There may be others.
If you "go big" for the right reasons - YOUR right reasons - that's fine.
The torque converter helps you off the line - it lets the engine slip up a bit and still multiplies the torque that's available there by almost 2. Stall ratios above 2 are possible, though I don't know if any are available for this tranny or whether they retain the lockup feature.
Slipping the clutch . . . if you really like to replace them frequently, it's one way to manage wheelspin. Pretty brutal though.
2nd and 3rd in the 5R55S AT are shorter than 2nd and 3rd in the TR3650 MT. So the AT needs LESS rear axle gear for those, not more.
At best, where the driving/racing uses 4th and 5th almost exclusively, the AT only needs the same gearing.
Norm
Last edited by Norm Peterson; Jan 24, 2010 at 06:28 PM.
5th Gear Member
Joined: Feb 2007
Posts: 2,211
From: Hawaii
Sorry. kings has it right.
The torque converter helps you off the line - it lets the engine slip up a bit and still multiplies the torque that's available there by almost 2. Stall ratios above 2 are possible, though I don't know if any are available for this tranny or whether they retain the lockup feature.
The torque converter helps you off the line - it lets the engine slip up a bit and still multiplies the torque that's available there by almost 2. Stall ratios above 2 are possible, though I don't know if any are available for this tranny or whether they retain the lockup feature.
so what happens when you are at a stop, and then nail the gas? roughly starting at 800 rpm's...and it will take a bit of time for the motor to "slip up a bit". that is lost performance and time
by running deeper gears, the tranny has more mechanical advantage from the very start...and if the torque converter is slipping, there is not a torque multiplication.
I don't know the stall ratio either, but if the motor spins say 2 revolutions for every 1 revolution of the tranny input shaft, that is a huge difference from a stick which has darn near always a 1:1 ratio.
Slipping the clutch . . . if you really like to replace them frequently, it's one way to manage wheelspin. Pretty brutal though.by running deeper gears, the tranny has more mechanical advantage from the very start...and if the torque converter is slipping, there is not a torque multiplication.
I don't know the stall ratio either, but if the motor spins say 2 revolutions for every 1 revolution of the tranny input shaft, that is a huge difference from a stick which has darn near always a 1:1 ratio.
on the strip yes, I agree somewhat
but for a daily driven car, where you are not staging, the 4.10 gears are better choice for a auto car.
the major disadvantage of auto's is their low end performance.
I wholly agree with you once they are rolling.
I wholly agree with you once they are rolling.
I wasn't very clear when I said "slip the clutch". Should have said you can hold the clutch in and rev up to 2,000-3,000 rpm and then launch. vice launching a auto at say 700-1,000 rpm
to get anything similar with an auto you'd need to do a brakestand or a line-lock.
and I think we can agree that doing that is incredibly hard on the tranny
I've done this exact mod before on my old Chevy truck. Initially had 3.03 gears and a 383 stroker motor. We did a 4.11 swap. Went from a pretty anemic 0-50 mph...to a rip roaring tire shredder. And that was before I put in the 1,800 stall.
With a stock TQ converter, 4.10 gears are perfect with an auto tranny...and for those wanting a bit more of the performance down low...4.30 gears are even better IMO