Differences between Getrag 282 and 284?

[GrandPrixGTP95]

I know that the 282's were used with the 3.1L equipped wbodies, and the 284 was used with the 3.4L DOHC, but what exactly are the differences? What made the 284 stronger than the 282? I really need to know, so any help at all would be greatly appreciated!

[Robby1870]

The clutch mechanism is different (push vs. pull) and the its very hard to find parts to rebuild/beef up a 284 whereas they is plenty of stuff for the 282

[no1kicker]

Aren't the gear ratio's a little different too?

[Robby1870]

yeah, they are. 284 is suited for the top end power of the LQ1

[GrandPrixGTP95]

you guys said that there is an aftermarket for the 282 right? What site/sites has parts for the 282 to be built up a bit? Anything that would make the tranny even the littlest bit stronger would be great.

 

Thanks

[Robby1870]

I dont know specific sites off hand, but I know plenty of clutches are made to handle a lot of power. Ive heard of many 282's mated to 300+HP motors. Just search on the net, something should pop up

[brian89gp]

Whats different? About 50lbs, gears, differential, case, axels, clutch, hydraulic clutch system, shift cables, mounts, pressure plate and TOB.

 

The only thing that is the same is the bellhousing bolt pattern...

 

And everyone that quotes "the 282's hold fine in V8 fiero's" remember that the fiero is a much much lighter car.

 

For gearing, the only page on my site that gets traffic: http://www.brian89gp.com/other/transmission.htm

 

And what made the 284 stronger? The dry weight of the 282 being near 100lbs and the dry weight of the 284 being 150lbs is a big clue. Everything is much bigger, a 282 sitting next to a 284 looks kinda puny.

[skalor]

Whats different? About 50lbs, gears, differential, case, axels, clutch, hydraulic clutch system, shift cables, mounts, pressure plate and TOB.

 

The only thing that is the same is the bellhousing bolt pattern...

 

And everyone that quotes "the 282's hold fine in V8 fiero's" remember that the fiero is a much much lighter car.

 

For gearing, the only page on my site that gets traffic: http://www.brian89gp.com/other/transmission.htm

 

And what made the 284 stronger? The dry weight of the 282 being near 100lbs and the dry weight of the 284 being 150lbs is a big clue. Everything is much bigger, a 282 sitting next to a 284 looks kinda puny.

 

Exactly why I used a 284 instead of a 282 in my TGP. I don't really see the gearing being only usuable for the 3.4 TDC as everyone usually states. In fact first gear is lower in the 282 than in the 284. I just see it as the gears are all equally spaced. If I shift at 5500 rpms, it takes me to 4000 rpms exactly in every gear. The 284 is designed to take the engine back to the same exact rpm after every shift. That's why is "designed" for the 3.4 TDC, it takes it to the same point in the powerband everytime you shift. 8)

 

In fact I'm curious to see what rpms you 282 guys see after shifting. As stated above, I'm seeing 4000 almost exactly after every 5500 rpm shift.

[Canada]

As his disclaimer states, there ARE some disscrepencies in the gearing on Brian89gp's website.

 

For one, the listing he has for Quad 4 282 gearing is actually for J and L Body V6's.

 

Quad 4's (HO's anyway) got a total of 4 different gearsets for 89-94.

 

89:

 

1st 3.50

2nd 2.19

3rd 1.38

4th 1.03

5th 0.72

Axle 3.61

 

90:

 

1st 3.50

2nd 2.19

3rd 1.38

4th 1.03

5th 0.81 (shorter 5th gear for stronger top end accel)

Axle 3.61

 

91:

 

1st 3.77 (shorter 1st for launch)

2nd 2.19

3rd 1.38

4th 1.03

5th 0.81

Axle 3.61

 

(These BTW, are the same as all of the W Body 282 V6's)

 

92-94:

 

1st 3.50

2nd 2.05 (revamped 2-3 gear spacing to help the horrible rpm drop for that shift)

3rd 1.38

4th 1.03

5th 0.72 (back to the long 5th.......it's actually close to the same with the 3.94 axle ratio)

Axle 3.94

 

(These are the same as SCX gears except for having a longer 5th).

 

 

 

 

As for gear spacing, a 5500rpm 1-2 shift on a 284 does NOT drop you to 4000rpm. It drops you to ~3625rpm............it's simple math.............(2.28/3.46 = 0.65896)* 5500 = 3624.28.

 

Easy.

 

For figuring out rpm drop for each gear, on the W-Body 282 and 284's, take you shift rpm * the % in the chart below to figure out your rpm off of the shift:

 

HM-282 (W-Body gears):

 

1-2 62.6%

2-3 63.0%

3-4 74.6%

4-5 78.6%

 

HM-284

 

1-2 65.9%

2-3 64.9%

3-4 73.6%

4-5 66.1%

 

 

As you can see, the 284 has *barely* closer spacing for the 1-2 and 2-3 shifts, but is actually LESS performance oriented for 3-4 and ESPECIALLY for 4-5. But that only takes into account gear SPACING............add in the slightly longer axle ratio of the 282, and you'll find that 1st gear is virtually identical between the two but the 282 has a ~6% longer 2nd, ~9% longer 3rd and ~8% longer 4th.........but a 10% SHORTER 5th (which would certainly help out top speed for ungoverned cars).

 

*MY* advice is that those looking for a sheer 1/4 mile car, should use the 284, but those who want more highway flexibility (and maybe the occisonal top end blast) should use the 282...............

[Nick1234]

i really wish i could find a donor car with a 282 and put it in my lumina. I want a manual car so bad. That, and the cam from gm performance parts, the car would actually have some balls. They would be marble sized instead of beebee size

 

nick

[GrandPrixGTP95]

So nobody knows any sites that have aftermarket products for a 282 at all? And thanks guys, this site is sooo much more informational than clubgp is, maybe I should start posting here...i've been a member for 2 years and have like 5 posts Thanks again

[soccrplayrgtp]

clubgp is very helpful as well other than when you are talking about manuals.... Not many Gp's had em.. but when you go to a WHOLE w-body club it covers all of the cars therefore getting more fan base on the manuals. thanx for the info so far guys; could always use MORE than what I have

[skalor]

As for gear spacing, a 5500rpm 1-2 shift on a 284 does NOT drop you to 4000rpm. It drops you to ~3625rpm............it's simple math.............(2.28/3.46 = 0.65896)* 5500 = 3624.28.

 

Easy.

 

Calculate this!!!

 

http://fp.enter.net/~nicolette/TGPshift.mpg

[god910]

Skalor, I don't see the tach you are pointing at, just the factory guages You should trust that tach as much as an exgirlfriend that cheated on you w/ 4 of your best friends at once. Man, that thing revs pretty slow. J/K I had a video of mine, no sound, but I'll see if I can find it.

[BIGBULS]

Calculate this!!!

 

http://fp.enter.net/~nicolette/TGPshift.mpg

 

What? You don't believe math?

 

I should point out that there is a lag time between the actual shift, and when the tach drops back down.............and on a car that pulls as hard as yours, you can have already acclerated a few hundred rpm worth in that short time (400+ rpm would be EASY to do)............ESPECIALLY if you tires are spinning slightly into the next gear.

 

The top of 1st gear (5500rpm with 245/50R16 tires and an ACCURATE speedomter) is @32mph with the HM-284............now, try driving along at 32mph (or whatever your speedo indicates 1st gear redline is)............I'll make a bet it's right around 3625rpm in 2nd gear (assuming your tach is accurate..........or at least inaccurate in a linear fashion).

 

For instance..........my NX2000 when shifted at it's 7500rpm redline drops to only around 5K rpm (due to the lag)..............but if I drive at the SPEED that 1st gear tops out at (38mph), I'm at only 4500rpm in 2nd.

 

As I (and Canada said)...........you car drops to 3625rpm off the 1-2 shift (from 5500rpm).

 

You can't argue with mathematics.

[skalor]

Obviously if I'm shifting at 5500 rpms I'm not doing it to muck around with what rpms I should be dropping to when I shift into the next gear. So, why in the world would I want to max out first gear at a steady speed and shift into second?? If I'm revving to 5500 rpms, then I'm doing it to beat some other car, and not to get it to drop to the proper rpm.

 

I'm accelerating so fast that by the time I shift I'm already past the speed that I left the previous gear in. I've even seen as high as ~4250 on a 1-2 shift if I shift quicker. I didn't spin into second on that run, but believe me I can . I stated in my earlier post that I see 4000 rpms after a shift and Canada stated that I Don't. I'm just proving my point... There are too many variables in just about any real world situation that makes it easily or accurately predictable with "simple math".

 

I know how far off a factory tach can be, but my TGPs tach is pretty close. It's about 100 rpms off at 3000 rpms when it was auto and it had the park/neutral rev limiter. I've never hit the 5975 rpm rev limiter so I don't know how far off it is higher up. I'm sure the tach is further off at 5500 rpms than it is at 4000 rpms so my point is still valid.

 

 

My friend has a '91 NX2k, but it's an auto. He's only run a 16.0 in the car with pretty big list of mods. He also has a '91 Sentra SE-R that we swapped in a U13 DET into it (most people would say that I did the swap, but it's his car ). I did all the fabrication on the car from the custom front torque mount, intercooler piping, BPV flange, and and I mounted the FMIC. We just ran an A/F controller for the stock DE computer since his DET didn't come with the MAF and it ran pig rich with the DET computer. He ran a best of a 13.6 @ 106 with S3 cams, aluminum flywheel, FMIC, drag radial(forget the size), and stock boost(~7.5 psi). He has a JimWolf($$$) computer coming with bigger injectors since the 370s are almost maxed out as it sits now. Gotta Love SR20DETs...they make my TGP look slow. That's why I'm getting a '99 GP GTX, but he doesn't know that yet.

[EurosportZ34]

Hrmmm....the 282 is for the 3.1 and the 284 is for the 3.4

[cryptnix]

what one would be best for mating to a l67? i want 5 gears and less hp loss ... as we expect from an auto ... so i wanna know out of the 282 and 284 would be best ... is it worth wasting my time?

[BIGBULS]

I'm accelerating so fast that by the time I shift I'm already past the speed that I left the previous gear in. I've even seen as high as ~4250 on a 1-2 shift if I shift quicker. I didn't spin into second on that run, but believe me I can . I stated in my earlier post that I see 4000 rpms after a shift and Canada stated that I Don't. I'm just proving my point... There are too many variables in just about any real world situation that makes it easily or accurately predictable with "simple math".

 

I think you missunderstood my point slightly there.........

 

You DO actually drop to down to 3600ish rpm off of the shift. It's the TACH that is slow to react (not necessarily that inaccurate, just slower to react), so that by the time the tach needle has dropped down from 5500, you actually ARE at 4K+............but AT the time of the shift, you are going to drop to 3600. Make sense? This is also why it drops LESS when you shift faster.......because you've aleady accelerated more in the next gear by the time the tach needle has dropped back down.

 

Remember...........unlike autos which actually DO accelerate during the shift (because the TC never fully unlocks), a manual stops AS SOON as you let out of the gas and/or dissengage the clutch.

 

So..........what you are seeing is simply tach lag..........I think that's what I (and Canada) were trying to illustrate (hence me using the "cruise at X speed etc" example).

 

 

 

 

I just got rid of my 93 Sentra SE-R (it had a couple of bolt-ons and ran low 15's), and my 92 NX2K hardtop is now my little project...........it recieved the Hotshot Intake and Header from the SE-R (I have UDP's too, but not on yet) and a FULL suspension (GC coilovers, AGX's, ST front sway bar, Progress rear sway bar, ES master bushing kit etc)............sooner or later (funds being the limiting factor), it will get one of three things: 1) a BB or Avenier DET swap, 2) a JGY DET clone kit (T25, 370's, HS FMIC pipe kit, JWT ECU etc.), or 3) a JGY Disco Potato (GT28RS) Kit ($3K though). I'd like 200-210whp with one of the two T25 setups (7psi), or 250-260whp with the Potato kit (12psi).

[BIGBULS]

what one would be best for mating to a l67? i want 5 gears and less hp loss ... as we expect from an auto ... so i wanna know out of the 282 and 284 would be best ... is it worth wasting my time?

 

A 284 is the beefier of the two, and would last the longest behind a modded L67.

 

But, *I* would simply snag a 4T65-E.............Intense has now gotten pretty good at building them, and since the 3800 SC makes so much torque, the auto isn't that big of a handicap.