Transmission & Gearing

whipped · Post by **whipped** » Mon Mar 06, 2006 11:10 pm

absolutely true... and then you've got problems with traction

I had to download a gear calculator to see where 2nd would drop me, and it's 3800 rpm at 40mph, shifting at 6600. (yes I'm lazy enough to d/l a calculator)

The Dark Side of Will · Mon Mar 06, 2006 11:31 pm

whipped wrote:I had to download a gear calculator to see where 2nd would drop me, and it's 3800 rpm at 40mph, shifting at 6600. (yes I'm lazy enough to d/l a calculator)

2nd with the 4T80E?
Even the 282 with its aweful 1-2 drop is better than that.

whipped · Post by **whipped** » Mon Mar 06, 2006 11:35 pm

The Dark Side of Will wrote:
whipped wrote:I had to download a gear calculator to see where 2nd would drop me, and it's 3800 rpm at 40mph, shifting at 6600. (yes I'm lazy enough to d/l a calculator)

2nd with the 4T80E?
Even the 282 with its aweful 1-2 drop is better than that.

yep, and that's with 3.73 final!

errr.... whoops, I might have missed a digit... hold up.
Nope, that's right. 2.96 1st, 1.63 2nd.

The Dark Side of Will · Mon Mar 06, 2006 11:37 pm

That doesn't affect the RPM drop

whipped · Post by **whipped** » Mon Mar 06, 2006 11:47 pm

The Dark Side of Will wrote:That doesn't affect the RPM drop

don't make fun of my leet transmission skillz

Series8217 · Post by **Series8217** » Mon Mar 06, 2006 11:50 pm

Why is GM so retarded when it comes to gear ratios in every damn transmission they make? Can't they make SOMETHING with decent ratios?

The Dark Side of Will · Mon Mar 06, 2006 11:51 pm

they do... It's called the T56 and it's only available in V8 powered RWD cars... IE a TINY fraction of the cars GM builds...

Series8217 · Post by **Series8217** » Mon Mar 06, 2006 11:53 pm

:cussing:

whipped · Post by **whipped** » Mon Mar 06, 2006 11:55 pm

what about the new transverse 6 speeds? both auto and manual... Or are they just for gas mileage again?

haha... someone should put in a longitudinal SBC with a T56, ditch the fuel tank and make it FWD... hahaha Stupid people always ask if it's FWD anyways

Aaron · Post by **Aaron** » Tue Mar 07, 2006 12:04 am

Series8217 wrote:Why is GM so retarded when it comes to gear ratios in every damn transmission they make? Can't they make SOMETHING with decent ratios?

As we've discussed a few times before, the 284 has amazing ratios, near perfect. Though a 6th would be nice to ease the 2-3 and 3-4. But that isn't their fault, it was mine. My motor would have done those much nicer with some tuning.

Overall I'm a fan of most GM gearing. Our LT1 6spd was great, I have no complaints on the Fiero 282, my buddy's Cavy Z24 is matched greatly to the stock 2.4 DOHC, etc. The only GM cars that I hated were their 3spd autos, but you can't do much with 3 or even 4 gears for that matter.

I think GM's 5-speeds are generally pretty nice.

The Dark Side of Will · Tue Mar 07, 2006 12:08 am

whipped wrote:what about the new transverse 6 speeds? both auto and manual... Or are they just for gas mileage again?

Dunno about the transverse 6 speed auto. I haven't seen ratios for it. The transverse 6 speed manual is el sucko. 3rd -6th look great, but 1st and 2nd are a fucking pile of shit. It has a bigger 1-2 RPM drop than the 282 does. WTF? And they call this a close ratio 6 speed?

The Dark Side of Will · Tue Mar 07, 2006 12:11 am

Aaron wrote:As we've discussed a few times before, the 284 has amazing ratios, near perfect. Though a 6th would be nice to ease the 2-3 and 3-4. But that isn't their fault, it was mine. My motor would have done those much nicer with some tuning.

Overall I'm a fan of most GM gearing. Our LT1 6spd was great, I have no complaints on the Fiero 282, my buddy's Cavy Z24 is matched greatly to the stock 2.4 DOHC, etc. The only GM cars that I hated were their 3spd autos, but you can't do much with 3 or even 4 gears for that matter.

I think GM's 5-speeds are generally pretty nice.

Your LT1 6 speed is indeed great.
The 284 is merely ok.
The 282 is atrocious. You lose 41% of your RPM on a 1-2 shift.

The T56 is nice because it has ratios similar to the old Muncie close ratio sets for 1st - 4th and then the spacing increases for 5th and 6th to give the car long legs on the highway.

The FWD transmissions are exactly the opposite... wider spacing in lower gears, closer spacing in higher gears. It's fucking ridiculous because that's bass-ackwards from the way the car is used.
I want the lower gears closely spaced so that I can have my fun up to 120 mph, then have a bigger gap so that I can have a nice tall 5th (and 6th) for good gas mileage.

Aaron · Post by **Aaron** » Tue Mar 07, 2006 12:29 am

The Dark Side of Will wrote:Your LT1 6 speed is indeed great.
The 284 is merely ok.
The 282 is atrocious. You lose 41% of your RPM on a 1-2 shift.

The 284 was as good as I could have hoped with the 3.4. Not perfect, but it was damn close. A 6th would have been nice, 5th was a little high RPm at 90+ mph.

I guess I don't notice it with the 282 cuz of the 2p8. I'm really not looking forward to it now though..

Ben, find better. The LT5 heads were better no doubt, and the LS7. The Quad 4 simply didn't flow as much, smaller all around. The only other possible heads are other DOHC heads. So N*, well they are smaller, don't flow as much (Made for lower RPM and midrange), so which are better?

Fastback86 · Post by **Fastback86** » Tue Mar 07, 2006 1:35 am

Slightly OT, but as I understand it, the 282 and 284 are Getrag 5spds, the Fiero one and the other FWD one. What is the general opinion on the gearing of the Muncie 4spds? I know the 4.10 is worthless for anything besides roasting tires, but what about the 3.63 and the 3.32? Just as bad as the Getrags? Better or worse? I also notice that no one seems to care about the Isuzus, but thats not surprising.

Aaron · Post by **Aaron** » Tue Mar 07, 2006 1:36 am

Fastback86 wrote:Slightly OT, but as I understand it, the 282 and 284 are Getrag 5spds, the Fiero one and the other FWD one.

The 282 was FWD and RWD. RWD only in the Fiero, FWD in Berettas and a bunch of other cars.

The 284 was only available FWD in the 3.4 DOHC W-bodies, and only from 91-93.

Fastback86 · Post by **Fastback86** » Tue Mar 07, 2006 2:13 am

The fact that the 282 was in the back of a Fiero doesn't make it a RWD transmission.

Aaron · Post by **Aaron** » Tue Mar 07, 2006 2:38 am

Fastback86 wrote:The fact that the 282 was in the back of a Fiero doesn't make it a RWD transmission.

How do you figure?

Last time I checked my Fiero was pretty RWD. I mean, the rears are the ones that are driven...

It was made with the intent to be a FWD trannsmission, but that doesn't mean it was never used in a RWD application.

Fastback86 · Post by **Fastback86** » Tue Mar 07, 2006 2:45 am

Its still a FWD transmission. Whens the last time you saw a transverse engine, RWD car? Hell, the whole Fiero drivetrain is a FWD drivetrain, its just in the back of the car. Funky application doesn't change the design of the trans.

Series8217 · Post by **Series8217** » Tue Mar 07, 2006 3:56 am

Aaron, you must be wrong. It drives the front my friend's W-body but the rear of my Fiero. It is an AWD transmission.

I've spent a lot of time looking at gear ratios for all of the available GM FWDtransmissions, and in my opinion the Isuzu holds the most potential because it has been used in so many applications that a wide variety of gear sets are available. There are sets that have decent 1 to 2 shifts. They are all interchangeable. 1 and 2 are a single part, 3 and 4 are a single part, 5 is seperate, final drive is seperate. Makes for a lot of gear ratio opportunities. The Isuzu also shifts more smoothly than the Getrag, and newer ones have triple synchros on second gear according to DreXter. Built properly and cryo treated I think the Isuzu is strong enough. It also doesn't have the diff carrier bearing wobble problem the Getrag's are so fond of producing after 50,000 miles.

The Dark Side of Will · Tue Mar 07, 2006 9:14 am

Hmm...

According to http://www.timken.com/industries/automo ... talog.aspx

Everything in the world uses Timken SET11 bearings on the diff (Getrag, Muncie, Pontiac 6000 AWD rear diff, Chrysler products, etc), but the Isuzu uses 32008XM bearings on the diff. Interesting.

I have been curious about the Isuzu, since it was used in Japanese cars. The story goes that the Japanese gearsets are stronger because GM was cheap and didn't want to pay for the extra heat treatment in an economy transmission.

Since it was used in SOOO many apps that I'm not familiar with, I hadn't tackled tracking down all the different ratios to see what would be nice. If you have that info, I'd be interested in seeing it. Start a new topic if you'd like.