Fox T-Bird/Cougar Forums

Technical => Drivetrain Tech => Topic started by: Dougy_Fresh on September 11, 2010, 11:05:58 PM

Title: gear/diff swap
Post by: Dougy_Fresh on September 11, 2010, 11:05:58 PM
ok, so i grenaded the tracloc diff in my bird, apparently 7.5's dont like 6000rpm launches....i'm done racing though, just trying to get it back on the road so i can get back and forth to my new job....

i found a ranger rearend i am buying to get the gears and diff out of, it's a open diff with 4.10's, it's only temporary so i'm not worried about it not being a locking diff...i'm going to be picking up a 3.55 or 3.73 geared 8.8 in a few months, i just need my car driveable now...

my question is, what are the chances of being able to just pull the diff and gears out of the ranger case and put them in my housing using the shims from the ranger axle and everything be ok?
Title: gear/diff swap
Post by: no911forme on September 12, 2010, 12:18:08 AM
(shaking the dice)..... come on baby.... daddy needs some gears.... :rollin:

Seriously... you might get lucky ...

I swaped out a set of 4.10's a couple months ago from a ranger also... had to change the carrier shims... man those things have gotten pricey.....
Title: gear/diff swap
Post by: Beau on September 12, 2010, 04:25:03 AM
Unless it has a trac-loc, I wouldn't even bother.

Plenty of vehicles to get a trac-loc, 3.55 or 3.73 gear from...

There's a chart that explains what vehicles came with what gear ratio, and if said vehicle had or was available with the locker or not.

I thought I had it saved, but I cannot find it.

How's your google fu?
Title: gear/diff swap
Post by: Haystack on September 12, 2010, 06:29:43 AM
373's or higher are all trac loc
Title: gear/diff swap
Post by: Sick88Tbird on September 12, 2010, 01:46:49 PM
Quote from: Haystack;335327
373's or higher are all trac loc


Negative....my regular parts store had little ranger delivery trucks with a 4 cyl and open 4.10 rear
Title: gear/diff swap
Post by: Haystack on September 14, 2010, 11:46:41 PM
Sorry for the bad info, from what I have seen they have been. I have checked a couple of 4banger stangs in the junkyard, and they all were, as well as my mark 7 rear from a turbo diesel.
Title: gear/diff swap
Post by: Dougy_Fresh on September 19, 2010, 03:32:53 AM
well, 4.10's are in...used all the shims from the ranger rearend and everything seems to be good so far...

i cant tell ANY difference in acceleration though...i was expecting a big change, but NOPE...the gears are shorter, but it doesnt seem like it pulls any harder...
Title: gear/diff swap
Post by: Sick88Tbird on September 19, 2010, 04:02:52 PM
Quote from: Dougy_Fresh;336011

i cant tell ANY difference in acceleration though...i was expecting a big change, but NOPE...the gears are shorter, but it doesnt seem like it pulls any harder...


Probably because your SD computer is going WTF???!!!! with the B303 cam...I guarantee a MAF swap will wake it up...but you really need a good set of valve springs to keep the valves from floating past 4500rpm too.

I'm not even trying to break your balls here.  HO springs aren't even adequate for a stock cam.  The MAF swap will bring more power in across the board due to the ability to properly and accurately meter the changes to the incoming air.  I don't even know why people buy MAF ecu's used for $125+ on the 'net, when you can get a reman unit with a 1yr warranty from most parts stores for around $100 and no core charge.

For an investment of $250-$300 and an afternoon's worth of work and some specialty tools, you could really wake your car up.

Good luck,
Don
Title: gear/diff swap
Post by: Masejoer on September 19, 2010, 04:13:44 PM
Quote from: Sick88Tbird;336046

stuff


What does that have to do from going to 4.10's from...2.73's? He'd still have some 50% more torque at the wheels in all gears.

Was your old rearend stock/2.73? If it was anything less than 3.55's before, the difference would be drastic, open differential or not. You sure you have the 4.10 ratio? Count the teeth?
Title: gear/diff swap
Post by: Sick88Tbird on September 19, 2010, 05:02:29 PM
Quote from: Seek;336048
What does that have to do from going to 4.10's from...2.73's? He'd still have some 50% more torque at the wheels in all gears.

Was your old rearend stock/2.73? If it was anything less than 3.55's before, the difference would be drastic, open differential or not. You sure you have the 4.10 ratio? Count the teeth?


It makes a huge difference when you have shiznit for power and aren't increasing the rev range of the engine.

You could put 5.xx gears behind a stock SO and I bet you'd be slower.  It's about the total combination...so many people miss that little fact.
Title: gear/diff swap
Post by: Beau on September 19, 2010, 05:42:11 PM
Quote from: Seek;336048
You sure you have the 4.10 ratio? Count the teeth?


I'd probably have verified this before doing any work.
Just because the door code says it's one thing, it could be yet another....


And for the post regarding the reman EEC's...too right.

I'd pay no more than 110 shipped for an A9L.
Title: gear/diff swap
Post by: Masejoer on September 19, 2010, 06:06:04 PM
Quote from: Sick88Tbird;336054
It makes a huge difference when you have shiznit for power and aren't increasing the rev range of the engine.

That makes no sense - gearing is gearing. If you have to shift every second, sure it'll slow you down, but gearing will always speed you up in your engine's power band. Now if your motor runs out of steam at 4000 rpm's and you're already in your 1:1 transmission gear, yes you'll slow down above that but everything below will have a huge performance improvement with 4.10's over 2.73's.

Quote from: Sick88Tbird;336054
You could put 5.xx gears behind a stock SO and I bet you'd be slower.

It'd still be quicker (with traction) in all gears - you'll just run out of power sooner as you use up all the gearing.

Also, what are you claiming would be "slower"? Quarter mile? I would agree that with a stock 5.0 SO revving engine would only benefit from about 3.55's with an aod and 3.31's with a t5 - if I remember right, the stock SO 5.0 does die off at 4k, although with my old tired one, it felt like it fell apart at 3.5k.

In the 1/8, 4.10's would work much better, with traction.

His 4.10's should have a huge seat-of-pants feel improvement.
Title: gear/diff swap
Post by: hypostang on September 19, 2010, 07:34:06 PM
Quote from: Seek;336063
His 4.10's should have a huge seat-of-pants feel improvement.



+1 on this 
 With no other changes at all, a gear swap should make a huge difference in seat of the pants feel .
 Greater torque multiplication gets the car moving more quickly period.
 Of course we still dont know what he was running for gears before the swap
Title: gear/diff swap
Post by: Haystack on September 20, 2010, 12:42:55 AM
If you've ever driven a stick shift car, this should be obvious. try starting out in second, then start out in first. If you really ride the clutch, you might not be able to tell any difference, but if you get it to 5mph and let the clutch go, I am sure first gear would be quicker.
Title: gear/diff swap
Post by: Dougy_Fresh on September 20, 2010, 07:16:06 PM
i had 2.73/tracloc before, 4.10/open now...

it runs good and pulls hard up to 6000rpms, it just doesnt seem like it accelerates any faster than before....wierd thing is it still hooks up...i just launched it at 4000rpm's in first and it only spun for a split second and it hooked and took off...
Title: gear/diff swap
Post by: Beau on September 21, 2010, 02:09:15 AM
As mentioned before, going from 2.73's to 4.10's, you should notice a very definite difference. Sounds like you got f*cked...

Then again, you have one bad-ass car that can do what no other Thunderbird can.  :rolleyes:
Title: gear/diff swap
Post by: 347Thunder on September 21, 2010, 09:37:50 AM
Quote from: Seek;336063
That makes no sense - gearing is gearing. If you have to shift every second, sure it'll slow you down, but gearing will always speed you up in your engine's power band. Now if your motor runs out of steam at 4000 rpm's and you're already in your 1:1 transmission gear, yes you'll slow down above that but everything below will have a huge performance improvement with 4.10's over 2.73's.



It'd still be quicker (with traction) in all gears - you'll just run out of power sooner as you use up all the gearing.

Also, what are you claiming would be "slower"? Quarter mile? I would agree that with a stock 5.0 SO revving engine would only benefit from about 3.55's with an aod and 3.31's with a t5 - if I remember right, the stock SO 5.0 does die off at 4k, although with my old tired one, it felt like it fell apart at 3.5k.

In the 1/8, 4.10's would work much better, with traction.

His 4.10's should have a huge seat-of-pants feel improvement.


thank you for that reply, I can't believe people say  they have no experience with!!!! probably the #1 performance upgrade is GEARS!!!
Title: gear/diff swap
Post by: Sick88Tbird on September 25, 2010, 11:09:33 AM
347Blunder....I have plenty of experience with gears.  With his combination...redneck thinking like yours is why so many people have the "bigger is better" complex.

More gear is better, isn't always the case.

My old SD AOD with 3.73's ran the same quarter and 1/8 times as my current MAF 351 T5 with 3.73's....and the 351 makes a bit more power and a ton more torque.  The 351 hooks up better with the 3.73's than the AOD car would....the 60' difference is only about .1 at most and this car is a bit heavier than the old one.

A car can "feel" a lot quicker without actually being quicker....FEEL is totally and completely subjective...what may feel like a HUGE difference to some may feel like a negligible difference to others.


Good luck,
Don
Title: gear/diff swap
Post by: hypostang on September 25, 2010, 11:27:07 AM
Quote from: Sick88Tbird;336633
347Blunder....I have plenty of experience with gears.  With his combination...redneck thinking like yours is why so many people have the "bigger is better" complex.

More gear is better, isn't always the case.

My old SD AOD with 3.73's ran the same quarter and 1/8 times as my current MAF 351 T5 with 3.73's....and the 351 makes a bit more power and a ton more torque.  The 351 hooks up better with the 3.73's than the AOD car would....the 60' difference is only about .1 at most and this car is a bit heavier than the old one.

A car can "feel" a lot quicker without actually being quicker....FEEL is totally and completely subjective...what may feel like a HUGE difference to some may feel like a negligible difference to others.


Good luck,
Don


Just out of curiosity are you saying steeper gears wont make a car quicker out of the hole ?That torque multiplication is irrelevant?

I'm just trying to understand here

Or are you saying TOO much gear on a given combo can be detrimental?
 I have always been under the impression that the best "bang for the buck" modification someone could do to make a car quicker, say 0-60 was steeper gears.
 Now I suppose I could be mistaken , but if that is the case I know a ton of other people who would love to know they are also wrong .

Please clarify what you are saying , and  please try to refrain from name calling , I am seeking insight not insults .
Title: gear/diff swap
Post by: turbo_88_XR7 on September 25, 2010, 11:27:41 AM
Quote from: Dougy_Fresh;336176
i had 2.73/tracloc before, 4.10/open now...

it runs good and pulls hard up to 6000rpms, it just doesnt seem like it accelerates any faster than before....wierd thing is it still hooks up...i just launched it at 4000rpm's in first and it only spun for a split second and it hooked and took off...


4.10's will hook better than a numerically lower gear
Title: gear/diff swap
Post by: Masejoer on September 25, 2010, 12:51:44 PM
Quote from: Sick88Tbird;336633
My old SD AOD with 3.73's ran the same quarter and 1/8 times as my current MAF 351 T5 with 3.73's

I'm confused - are you trying to make a case FOR gears or against it? From what you're saying above, you're claiming that the weaker motor with lower gears (numerically higher) performs near your 351W - this right there shows that the gearing helped dramatically in the 1/8 and 1/4. What was the speed density 5.0 putting out in terms of torque and horsepower? While the stock SO would die at the top end with 4.10's in the quarter, the gears are still a huge improvement over 2.73's.

Of course the 351 would have more torque out of the hole and be more difficult to keep traction and be harder to feed up top so 4.10's very well could be detrimental. Only half of this is true with the stock SO motor.
Title: gear/diff swap
Post by: Beau on September 25, 2010, 01:51:47 PM
Quote from: turbo_88_XR7;336638
4.10's will hook better than a numerically lower gear


I thought tires hooked...not gears? ;)

My bet is still on that the OP does NOT have 4.10's.

I'll eat my words if he shows proof of those gear being in fact what he says though.


He's also said a lot of other  that really doesn't make sense, that defies what is known as utter truth in our world of FoxCatBirds. (anyone remember his posts/threads about a SO pulling past 4k rpm? lol)

With that, I'm out...
Title: gear/diff swap
Post by: Masejoer on September 25, 2010, 02:14:48 PM
Quote from: ThunderbirdSport302;336659
I thought tires hooked...not gears? ;)


Hah, yeah - that didn't make any sense to me either but I figured I'd just ignore it. Lower numerical gears would "hook better" if you just slam on the gas pedal as there's much less torque - higher numerical is just the opposite.
Title: gear/diff swap
Post by: Sick88Tbird on September 25, 2010, 03:05:42 PM
What I'm saying is that too much gear can be a bad thing.

My old SD 5.0 was a stock HO with LT headers and exhaust.  From 2.73's to 3.73's in that car was worth just under 4 tenths.  That's not a HUGE difference.  In a car with less power and torque(because his SD computer is confused about the B-cam) it would be even less dramatic...his car is most likely pig fat rich at low rpm and goes crazy lean after 2500-3000.

Like I said before...you need the right gear for the combination....or at least make sure you're getting what you pay for!  lol

Hey, we don't all have to agree....it's the internet...we just have to try to be civil about it.  That's what seperates us, as an internet community, from other forums.

-Don
Title: gear/diff swap
Post by: hypostang on September 25, 2010, 03:59:10 PM
Quote from: Sick88Tbird;336663
What I'm saying is that too much gear can be a bad thing.

My old SD 5.0 was a stock HO with LT headers and exhaust.  From 2.73's to 3.73's in that car was worth just under 4 tenths.  That's not a HUGE difference.  In a car with less power and torque(because his SD computer is confused about the B-cam) it would be even less dramatic...his car is most likely pig fat rich at low rpm and goes crazy lean after 2500-3000.

Like I said before...you need the right gear for the combination....or at least make sure you're getting what you pay for!  lol

Hey, we don't all have to agree....it's the internet...we just have to try to be civil about it.  That's what seperates us, as an internet community, from other forums.

-Don


Ok, now I understand what you are saying, and I agree, like any modification ...the combination is critical .
Kinda like dumping a 1050cfm Holley  dominator on a completely stock  255 ci 81 Granada  wouldn't work out very well  .
 But I do stick by my stance that with absolutely no other modifications  gears will give you the best "bang for the buck" 0-60 :D
Title: gear/diff swap
Post by: 347Thunder on September 25, 2010, 04:55:09 PM
Quote from: Sick88Tbird;336663
What I'm saying is that too much gear can be a bad thing.

My old SD 5.0 was a stock HO with LT headers and exhaust.  From 2.73's to 3.73's in that car was worth just under 4 tenths.  That's not a HUGE difference.  In a car with less power and torque(because his SD computer is confused about the B-cam) it would be even less dramatic...his car is most likely pig fat rich at low rpm and goes crazy lean after 2500-3000.

Like I said before...you need the right gear for the combination....or at least make sure you're getting what you pay for!  lol

Hey, we don't all have to agree....it's the internet...we just have to try to be civil about it.  That's what seperates us, as an internet community, from other forums.

-Don


so, being civil means name calling, why would you refer me to a redneck when I'm BLACK!! not cool. No since arguing with the only person right on this topic. You win :bowdown:LOL your right about one thing bigger isn't always better, or are you, I never herd that term come from anyone that made any sense:punchballs:
Title: gear/diff swap
Post by: Beau on September 25, 2010, 04:58:03 PM
Quote from: hypostang;336666
Ok, now I understand what you are saying, and I agree, like any modification ...the combination is critical .
Kinda like dumping a 1050cfm Holley  dominator on a completely stock  255 ci 81 Granada  wouldn't work out very well  .
 But I do stick by my stance that with absolutely no other modifications  gears will give you the best "bang for the buck" 0-60 :D


Within reason, yes, I'll bite.

Quote from: myself
My bet is still on that the OP does NOT have 4.10's.

What's that they say? Pics or GTFO...? :flip:
Title: gear/diff swap
Post by: 347Thunder on September 25, 2010, 05:09:40 PM
oh, I'm not really black :rollin::mullet:
Title: gear/diff swap
Post by: turbo_88_XR7 on September 25, 2010, 06:43:20 PM
Quote from: ThunderbirdSport302;336659
I thought tires hooked...not gears? ;)

alright, i failed at explaining lol.. ask any racer, not some guy crusing around on the streets.. 4.10's will hook the tires better than, say, 3.08's or something of that drastic difference
Title: gear/diff swap
Post by: Beau on September 25, 2010, 07:03:57 PM
I know, I were teasin lol. I went from 2.73's to 3.55's...I know what a "kick in the ass" that was.

If DougyFresh had a set of 4.10's in after some higher gears...I doubt he'd have posted here askin' wtf it didn't have a bit more..."git up and go" lol
Title: gear/diff swap
Post by: turbo_88_XR7 on September 25, 2010, 07:12:13 PM
yeah, but someone could have put a set of 3.73's in it at some point.. that would explain why there was no significant notice in acceleration gain

but a 6K RPM launch.. WTH!? no wonder his original rear went POOF lol
Title: gear/diff swap
Post by: Masejoer on September 25, 2010, 10:18:30 PM
Quote from: turbo_88_XR7;336696
alright, i failed at explaining lol.. ask any racer, not some guy crusing around on the streets.. 4.10's will hook the tires better than, say, 3.08's or something of that drastic difference


Maybe I'm dense or something but this still makes no sense? "Hooking" is having traction. Higher numerical gears will give you more torque multiplication, making traction a problem which is NOT "hooking". Unless you're meaning something else that isn't processing in my head?

Breaking the tires free != hooking. Of course, breaking the tires free on shifts is nice and all, especially if you have some nice fat ones, but also a hazard to everyone (on road) and a waste of power.

I agree on the 6k launches - doesn't seem very beneficial on anything but helping get out of the hole quicker with a lower performance motor. I like not having traction at times - it keeps the car from getting overly expensive.
Title: gear/diff swap
Post by: Beau on September 25, 2010, 11:39:44 PM
I'm just waiting on the OP's next post in regards to finding the next weak link.

Of all the cars I've had, only the Sport has my respect in regards to power. I've made it what it is (understandably, not much haha) and I'd be very hesitant about 6,000 rpm clutch drops...

All my other cars I ran the piss and vinegar out of, and truly, only three have survived. The Blue truck I drive now, my white Tbird, and my '92 F-150.
What killed the white car was me...under some chemical influence attempting to drive it home without checking the oil (horrendous rear main leak) and ended up with a ventilated pan, yadda yadda.


"If you drive it like you hate it, eventually you will."  :rollin:
Title: gear/diff swap
Post by: turbo_88_XR7 on September 26, 2010, 01:20:44 AM
Quote from: Seek;336719
Maybe I'm dense or something but this still makes no sense? "Hooking" is having traction. Higher numerical gears will give you more torque multiplication, making traction a problem which is NOT "hooking". Unless you're meaning something else that isn't processing in my head?

Breaking the tires free != hooking. Of course, breaking the tires free on shifts is nice and all, especially if you have some nice fat ones, but also a hazard to everyone (on road) and a waste of power.

I agree on the 6k launches - doesn't seem very beneficial on anything but helping get out of the hole quicker with a lower performance motor. I like not having traction at times - it keeps the car from getting overly expensive.



it has something to do with a lower(numerically lower) gear trying to turn the tires faster(speedwise, not acceleration wise).. i just know what was told to me and what i've witnessed. my camaro with low(numericaly) gears spun like crazy when launching at 3K, even with my locker.. when i put 4.11's in it, i was able to hook when launching at 3400, my converters breaking point(so to speak)
Title: gear/diff swap
Post by: turbo_88_XR7 on September 26, 2010, 01:22:07 AM
Quote from: ThunderbirdSport302;336730
"If you drive it like you hate it, eventually you will."  :rollin:



i like that motto hahah
Title: gear/diff swap
Post by: Masejoer on September 26, 2010, 11:30:03 AM
Quote from: turbo_88_XR7;336735
it has something to do with a lower(numerically lower) gear trying to turn the tires faster(speedwise, not acceleration wise).


3k rpm's in lower numerical gear would be at a higher speed than in a higher numerical gear, say 30mph versus 20mphso yes, although normally the lower numerical gears would just bog down unless you h ave extremely poor traction. I get what you're saying there though. It has nothing to do with "hooking" itself - it's hooking at the same engine rpm's that is the problem.
Title: gear/diff swap
Post by: turbo_88_XR7 on September 26, 2010, 03:31:15 PM
wheel speed is a problem as well when it comes to the tires gripping. but what happened to the thread starter? i think he ran away lol
Title: gear/diff swap
Post by: Masejoer on September 26, 2010, 03:45:40 PM
No idea - he was on 3 days ago.
Title: gear/diff swap
Post by: Dougy_Fresh on September 26, 2010, 10:43:40 PM
dont get on here much guys. my ring and pinion tooth count is 41 ring gear/10 pinion. i'm not pulling it back out to take pictures...

after driving it a while i can honestly say i my first impression of the gears was wrong...it accelerates a LOT harder now than it did before...only complaint i have is, well, i really dont have one....still getting 20+mpg and if i can get the occasional shiznitty running it has out of it, the mpg will get even better...
Title: gear/diff swap
Post by: turbo_88_XR7 on September 26, 2010, 10:55:43 PM
there's an easier way to get a ballpark number.. but you'd have to drop your driveshaft lol
Title: gear/diff swap
Post by: Beau on September 26, 2010, 11:24:34 PM
Quote from: turbo_88_XR7;336885
there's an easier way to get a ballpark number.. but you'd have to drop your driveshaft lol


Jack the rear, and neutral.

Turn the shaft by hand, watch the wheels and shaft, and count 'em.

Done deal :D
Title: gear/diff swap
Post by: turbo_88_XR7 on September 26, 2010, 11:30:17 PM
ah .. all this time and i never thought of it that way.. lmao.. 4.10's will be 4.1 rotations of the driveshaft to 1 turn of the axle
Title: gear/diff swap
Post by: Dougy_Fresh on September 26, 2010, 11:45:18 PM
OR, you simply divide the numbers that i KNOW, 41 teeth on the ring gear, divided by 10 teeth on the pinion equals 4.10...

i know for a fact that i put 4.10's in it, i even put the 4.10 axle tag on it...lol
Title: gear/diff swap
Post by: turbo_88_XR7 on September 27, 2010, 12:39:49 AM
that works too lol
Title: gear/diff swap
Post by: Sick88Tbird on September 28, 2010, 12:45:40 PM
I'm confused by your sig DougyFresh...SD HO conversion, then something about MAF?

Have you already converted, or just have to get the ECU and MAF harness?
Title: gear/diff swap
Post by: Dougy_Fresh on September 28, 2010, 06:32:40 PM
everything after the "..." is coming soon....

the car is running good as is SD...i'm going to do the heads, intake, TB, and MAF at the same time...because i know at that point my vacuum signal would be beyond screwed up which is why people say you cant run an aftermarket cam in a SD engine...
Title: gear/diff swap
Post by: Sick88Tbird on September 29, 2010, 07:57:48 AM
With a B cam the vacuum signal is already shot in the @$$...it may SEEM to run good.  I can assure you though, if you had a wideband O2 on it, you'd see that it is not.

Good luck,
Don
Title: gear/diff swap
Post by: turbo_88_XR7 on September 29, 2010, 10:36:31 AM
i was once told that the B303 is better suited for a manual car.. true or were they blowing smoke up my :shakeass:?
Title: gear/diff swap
Post by: Dougy_Fresh on September 29, 2010, 12:02:14 PM
i do have a 5 speed in my car....
Title: gear/diff swap
Post by: turbo_88_XR7 on September 29, 2010, 01:14:29 PM
i'm just asking a general question, because it's something i've heard a few times from different people
Title: gear/diff swap
Post by: Sick88Tbird on September 29, 2010, 05:43:09 PM
The B-cam is better suited to a 5-speed...in a MAF car.  It's down on low speed torque when compared to the E-cam...a lot of people just look at advertised duration and lift, but if I remember correctly, they have different LSA's, which will make a huge difference.
Title: gear/diff swap
Post by: turbo_88_XR7 on September 29, 2010, 06:06:39 PM
that's what i thought, good to know it's solid info
Title: gear/diff swap
Post by: Sick88Tbird on October 02, 2010, 08:26:47 PM
I think that, according to all of Dougy's posts, his seat-of-the-pants dyno needs to be recalibrated...regularly.

Good luck!
-Don
Title: gear/diff swap
Post by: Beau on October 03, 2010, 12:54:32 AM
Quote from: Sick88Tbird;337657
I think that, according to all of Dougy's posts, his seat-of-the-pants needs to be recalibrated by a steel-toed boot regularly.


Fixed, :evilgrin::rollin::D
Title: gear/diff swap
Post by: turbo_88_XR7 on October 03, 2010, 01:17:41 AM
:laughing: