GutlessSupreme Posted April 1, 2008 Report Share Posted April 1, 2008 Ok, so I guess it's time we settle some things, since I'm bored and my 282 is sitting partially disassembled on my workbench. To the best of my knowledge, my 282 came out of an '89 Cutlass International. I'm 75% sure that w-body bolt-in 282s came ONLY in w-bodies; meaning that no other 282 case has the mounting provisions on the bottom for our subframe-tranny mount. As with all other W 282s, the slave cylinder is externally mounted with an internal arm/fork setup. The trans has the old style (pre-'91) differential, which has a cast finish, a larger diameter pinion shaft (chrome in appearance) small spider gears and a 34 tooth gear for the Hall Effect electronic speedo sensor. The '91+ 282/T550 differential has a machined finish, larger spider gears, a smaller, but hardened, black pinion shaft that lacks the groves the old ones do, and is much stronger. Thanks to Fierobsessed from fiero.nl for that info. The following numbers are tooth counts for each gear that I just went out and physically counted myself. Input shaft Input splines: 14 1st drive gear: 14 2nd drive gear: 20 3rd drive gear: 24 4th drive gear: 35 5th drive gear: 43 Output shaft FDR drive gear: 18 1st driven gear: 49 2nd driven gear: 41 3rd driven gear: 33 4th driven gear: 33 5th driven gear: 31 Reverse gear: 41 Carrier FDR driven gear: 65 VSS ring: 34 Reverse Idler Shaft Reverse idler gear: 29 The following numbers are from a 1987 "Muncie Getrag" 282 service guide from GM. 1st: 3.50:1 - drive: 14, driven: 49 2nd: 2.05:1 - drive: 20, driven: 41 3rd: 1.38:1 - drive: 24, driven: 33 4th: 0.94:1 - drive: 35, driven: 33 5th: 0.72:1 - drive: 43, driven: 31 R: 3.41:1 - drive: 12 FDR: 3.61:1 The only other listed options in this '87 guide was an alternate for 2nd: 2.19:1 - drive: 21, driven: 46, which went into the MG1 trans (4cyl - we have MG2 - V6) and the alternate VSS sensor rotor with 28 teeth. I wish I could find a newer guide to get some of the later gearing straightened out. But there you have it. W-body V6 Getrag 282 gearing is 3.50/2.05/1.38/0.94/0.72/3.61. This is the numerically lowest/longest gearing available for any 282 trans, so any hopes of swapping gears from other 282s to lower the revs a little are gone. I'm trying to get a full page together on all the Getrag/Muncie/NVG 282 information out there, but it could take some time. Quote Link to comment Share on other sites More sharing options...
ismellrealbad Posted April 1, 2008 Report Share Posted April 1, 2008 Is the stronger 282 diff possible to be swapped in. Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 1, 2008 Author Report Share Posted April 1, 2008 Yes, the 91+ diff is a direct swap. But, and I don't remember the exact info here at the moment, the diff must be reshimmed to the correct preload. There was a post on Pennock's I think that explained exactly how to check for the new shim size without using the Kent Moore tools, I'll find the link later. Quote Link to comment Share on other sites More sharing options...
93CutlassSupreme Posted April 1, 2008 Report Share Posted April 1, 2008 This needs to be stickied. Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted April 2, 2008 Report Share Posted April 2, 2008 This needs to be stickied. Here, AND on 60 deg forums (I think they already corrected it though). I had long thought that W-Car's with the V6/282 combo had the same gearing as 91 Q4 HO's in L and N cars (3.77, 2.19, 1.38. 1.03, .81 with a 3.61 FDR). But I am REALLY glad somebody got bored and counted (especially now that I can see gearing down to the thousandth.........I'm weird like that ). Either way, it appears that W, L and J cars with the OHV V6's ALL are geared the same (as are 5 speed Fiero's IIRC). Sucks for the turbo guys........... Quote Link to comment Share on other sites More sharing options...
ismellrealbad Posted April 2, 2008 Report Share Posted April 2, 2008 Curious, whats the top speed in 5th assuming you have the power? Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted April 2, 2008 Report Share Posted April 2, 2008 Curious, whats the top speed in 5th assuming you have the power? A LOT..... Lets see...........we'll go with a set of 225/60R16 tires..........how about some Goodyear Regatta II's (there is a set sitting in the parts department through the door behind me (I'm at work fucking off obviously ). Anyway, Regatta II's in that size are at 783 revolutions per mile according to Tirerack. Now, 5th gear is a .7209302:1 ratio. We'll just call that .721 FDR is a 3.611111:1. Again, we'll shorten that to a 3.611. So, total gear multiplication of 2.603531:1. Multiplied by 783 = 2038.56rpm at 60mph (1 mile per minute). So...........add in your redline and do the math Either way, a stock 6000rpm redline OHV engine would be able to pull to ~176.60 mph before the rev limiter called it quits. Rev higher and you go faster.......... I REALLY doubt a stock 3.1L MFI would go past 120mph though (4075ish rpm). And that's at BEST. Physics is a cold bitch (aerodynamic drag in this case). Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 2, 2008 Author Report Share Posted April 2, 2008 So at 5k RPM, you're moving 147 mph or so with 225/60s. 5500 RPM = 162 mph. Well faster than I'd ever feel safe in a W-body [rpm / (gear multiplication * tire rotations per mile)] * 60 = mph Now someone find the CD for each of our cars and CF for there tires against the road, so we can calculate the torque needed to reach that speed. The PDF from GM I have has the spin-loss in Nm vs RPMs for each gear for the 282... in other words, the loss in power due to friction from 2k to 4k RPMs for each gear. Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted April 2, 2008 Report Share Posted April 2, 2008 Now someone find the CD for each of our cars and CF for there tires against the road, so we can calculate the torque needed to reach that speed. The PDF from GM I have has the spin-loss in Nm vs RPMs for each gear for the 282... in other words, the loss in power due to friction from 2k to 4k RPMs for each gear. Don't forget frontal area..........CD is worthless without knowing how MUCH air you are moving aside, and vice-versa. An easier way (ok......maye not, but more fun at least) would be to do a top speed run (with no governor), GPS it to makes sure the speed is accurate and record the rpm. Then go dyno the car and see how much power it makes at said rpm..............then, knowing that, go from there. Just remember that the power needed to overcome aero drag cubes as speed increases (anlthough tire drag etc is linear). Eg: A 3.1L MFI car will pull to around 115mph (governor or not....they are DONE), spinning 5000ish rpm in 3rd. At this rpm an auto trannied LHO makes ~100whp. So.........to go 135mph (~17.5% more speed), will require just under 65% more power AT the rpm you would be at at said speed (~6K rpm). So..........if 100whp gets you 115mph, then 135mph will require something in the order of 162ish whp AT the said 6K.......... Make sense? Also, be sure to err on the high side as tire rolling resistance is also sneaking upward......... That's kinda generic, but it gets you pretty darn close (since aero drag is the BULK of what you have to overcome). Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 2, 2008 Author Report Share Posted April 2, 2008 I'm actually calculating it now.. it uses a lot of generic #s so I don't have to calculate the actual CRR of the tires and actual area of the front of the car, but it should be reasonably close. Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 2, 2008 Author Report Share Posted April 2, 2008 The net force required to maintain 150 mph (241.4 km/h) is roughly 800 N, which translates to just over 190 ft-lbs (~260 Nm) at the wheels (using 225/60R16 Goodyear Regatta II's ). This is assuming: the vehicle weighs 3600 lbs is at sea level ambient temp = 70*F frontal area of vehicle = 8.5 sqft coef. rolling resistance for tires = .01 pretty much the only known value I had was the CD for a grand prix (0.299) everything else is based on a lot of assumptions and rounding, but ah, such is the life of a young engineer So at 150: 150/60 * 2.604 * 783 = 5097 rpm (190 ft-lbs * 5097 rpm) / 5252 = 184 hp at the wheels to maintain 150 mph Quote Link to comment Share on other sites More sharing options...
ismellrealbad Posted April 3, 2008 Report Share Posted April 3, 2008 :exclaim:. Wow, I'm lost after the first response to my ?, but this is some awesome info once I ever understand it. I'm glad you guys know what ur talkin about. Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted April 3, 2008 Report Share Posted April 3, 2008 The net force required to maintain 150 mph (241.4 km/h) is roughly 800 N, which translates to just over 190 ft-lbs (~260 Nm) at the wheels (using 225/60R16 Goodyear Regatta II's ). This is assuming: the vehicle weighs 3600 lbs is at sea level ambient temp = 70*F frontal area of vehicle = 8.5 sqft coef. rolling resistance for tires = .01 pretty much the only known value I had was the CD for a grand prix (0.299) everything else is based on a lot of assumptions and rounding, but ah, such is the life of a young engineer So at 150: 150/60 * 2.604 * 783 = 5097 rpm (190 ft-lbs * 4354 rpm) / 5252 = 184 hp at the wheels to maintain 150 mph While I don't have a frontal area for a W Car, I *DO* know the frontal area for my NX is 19.7 sq/ft and my old SE-R was 20.2 or 20.4...........pretty sure a GP is closer to 24-25 sq ft Plus...........calculations aside......... I would bet $ that it takes closer to 220-225whp (as measured by a Dynojet at least) to run 150 (again........AT whatever engine rpm your gearing puts you at). So......... Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted April 3, 2008 Author Report Share Posted April 3, 2008 I had found some site that had a couple of figures for frontal area (prolly wikipedia ) it said something like 5.x sqft for an Insight, 20 something for a Hummer lol. Average large sedan was supposed to be around 8.5. Looking at the cars now I would say it's prolly higher than that by a few sqft. I would assume, though, that only the y-components of the actual area (perpedicular to plane of travel) would count for drag, at least for my theoretical purposes lol. Changing the frontal area would definitely make a pretty significant change in the force needed to overcome wind resistance, though. Quote Link to comment Share on other sites More sharing options...
PCGUY112887 Posted April 3, 2008 Report Share Posted April 3, 2008 I can easily max out my spedo Quote Link to comment Share on other sites More sharing options...
BIGBULS Posted April 3, 2008 Report Share Posted April 3, 2008 I can easily max out my spedo Yeah but it only goes to 115mph Now if you could bury the speedo on my Prelude or my NX (both go to 150mph), THEN I'd be a touch more impressed............. BTW........the farthest I have gotten the Prelude is 144mph indicated (138mph ACTUAL per my GPS), and the NX has gone to 145ish mph indicated (141-142 per the GPS). The NX had a light downhill grade on it's side when this happened though.......... Quote Link to comment Share on other sites More sharing options...
MonteCarloDude Posted April 3, 2008 Report Share Posted April 3, 2008 I can easily max out my spedo Yeah but it only goes to 115mph Quote Link to comment Share on other sites More sharing options...
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