NoCoast Grant Hughes Infallible Moderator Location: Whitefish, MT Join Date: 01/11/2006 Age: Midlife Crisis Posts: 6,818 Rally Car: BMW |
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danster Haggis Muncher Professional Moderator Location: Haggisland UK Join Date: 01/04/2013 Age: Possibly Wise Posts: 409 Rally Car: VWs (for my sins) |
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Dante Allan Dantes Super Moderator Location: Herman, MI Join Date: 01/27/2006 Age: Midlife Crisis Posts: 176 Rally Car: 87 Mazda LSRX-7 |
200% upgrade Owner, Driver, Head Mechanic, and Janitor at Tower City Race Team, headquartered near L'Anse. Michigan. Driver / CoDriver in Rally America, NASARallySport, ARA, AMS, UPMDA, Champ Off Road https://www.facebook.com/TowerCityRaceTeam/ https://www.instagram.com/towercityraceteam/ |
mekilljoydammit Elite Moderator Join Date: 09/22/2010 Age: Midlife Crisis Posts: 336 Rally Car: No rally car yet |
Sometimes, people with aftermarket diffs are talking in terms of deactivating some of the plates because the sucker can lock too hard for their circumstances; two inner plates then two outer plates next to each other instead of inner/outer/inner/outer for example. Dunno if that's relevant in rally where some people are going to spools but there it is.
Other times, people are dumb. |
DaveK Dave Kern Mega Moderator Location: Centennial Join Date: 07/11/2008 Age: Midlife Crisis Posts: 1,085 Rally Car: Compact M3 & Evo IX |
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Aaron Luptak Aaron Luptak Mega Moderator Location: SLC Join Date: 02/15/2008 Age: Midlife Crisis Posts: 776 Rally Car: Civic... |
You should totally get a stage 2 diff. way better than any of that percentage garbage.
KF7RWG http://www.utahrallygroup.com |
john vanlandingham John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
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NoCoast Grant Hughes Infallible Moderator Location: Whitefish, MT Join Date: 01/11/2006 Age: Midlife Crisis Posts: 6,818 Rally Car: BMW |
I guess I shoulda quoted the % upgrade part. I have two bins full of shit.
BUT, NEWS FLASH!!! As of today I will offer a 75% upgrade to ANY and ALL drivers with an open diff! Just send me a message and $5 and I will send you the secret. But really, WTF are they talking about? Grant Hughes |
john vanlandingham John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
maximum speed differential side to side..
A good modern clutch palte diff since early 90s may be a "90% lockup" never allowing more than 10% speed difference side to side. Old school early 70s thing might be ---(ZF uses usually will see a big S on the case and an S in the ID tag, that's Krautski talk for ''sperr" like in:) 25% and moving the plates to proper stack (rather than stacking the 2 of the same thing on top--making a fat driven and a fat driving per side) would bump that to 40%....or max 60% speed difference... As you see it's a German thing, so naturally you should look there for ''einlichtung"
English is just a variant of the North-western branch of German so this should be easy for you. John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
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danster Haggis Muncher Professional Moderator Location: Haggisland UK Join Date: 01/04/2013 Age: Possibly Wise Posts: 409 Rally Car: VWs (for my sins) |
What type of diff? A standard plate diff, a plate diff with ramps, an ATB diff, a viscous diff, ... etc. All of them will have different ways of tweaking. If the % is just marketing jargon it could mean anything. eg. X% increase in preload, X% increase in surface area of plates, X% decrease in ramp angles giving more bite or compressive load on the plates. What parts did the kit include? Some pics to compare the upgraded parts against the standard bits would help. Disappointingly not yet a Jackass |
NoCoast Grant Hughes Infallible Moderator Location: Whitefish, MT Join Date: 01/11/2006 Age: Midlife Crisis Posts: 6,818 Rally Car: BMW |
Man, tough crowd in here today...
1. Not from anything I'm looking at buying, just see it on occasion, for example, Matt Bradenenenburg or whatever his name is, on his BMW rally car ran at 100AW, he said, we upgraded with a 60% diff. See if on occasion on other shit where they talk about percentages on the diff... 2. I do not care about nor look at anything other than clutch pack style differentials. So how can the allowed speed difference be controlled? Friction material, number of plates, and installing discs backwards? I'm pretty certain this is one of those wanky wanky pavement pounding things where people can be all like, "well based on this track I should have at maximum a 40% speed difference on the tightest corner so I want a 40% diff from _______, here's $2000 and thanks." Grant Hughes |
danster Haggis Muncher Professional Moderator Location: Haggisland UK Join Date: 01/04/2013 Age: Possibly Wise Posts: 409 Rally Car: VWs (for my sins) |
This is why it is good to discuss and learn as much as we can from one another to make sure nobody has a few too many beers of an evening and accidentally purchases the wrong thing for their particular application.
If I woke up after a heavy night on the ales and found I had ordered this 80% upgrade for a VW 020 box that was going to miraculously transform my car and make me a Seb Loeb beating master behind the wheel, I think I would hang my head in shame and embarrasment when the hangover kicked in and the cold feeling of reality came back to my sober mind. Disappointingly not yet a Jackass |
john vanlandingham John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
rotsa ruck, round eye... John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
The percentage is relative to wheels speed as John mentioned (I htink, and from what little you can actually find on teh topic). This can be adjusted by shimming the plates and allowing more initial preload to the clutch pack. Alternating disk position will also alter the amount of torque the diff can allow side to side. Also, I'm not sure how teh spider gears preload the clutch pack, but input torque from the drive shaft can also have an impact on the amount of lock-up the dif can provide. |