BRM 4.08 rearend swap now available!
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#RealRiceGSR#
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q45denver
You need to update your e-mail in the forum control panel, your e-mail is invalid.Thanks
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HeavyDuty
- Posts: 1281
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- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
Michelin Pilot Sports are the shiznit AFAIC for this app, and yes, centrifugal force with respect to tire growth is one to be reckoned with. 
Make mine a 3.80, my trap speed will be the same in the 1/4, albeit 1/10th second off, <maybe> 2, but with less engine beating rpm's at highway speed, yet a streetlight to streetlight advantage I sorely need.
HD
Make mine a 3.80, my trap speed will be the same in the 1/4, albeit 1/10th second off, <maybe> 2, but with less engine beating rpm's at highway speed, yet a streetlight to streetlight advantage I sorely need.
HD
602-828-8908
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
Q45 Differential pics.
OK, so I took a couple of minutes to clean & inspect my new diff. I can pretty quickly see a couple of issues we're going to run into on a gear swap, but nothing that should require the services of a Shaman.
Diff cover removed,
Cover....blekk, covered in baked on Gra-Doo. Since the cover is aluminum & the fins are there to dissipate heat, any road grime or leaking gear oil gets baked on & reduces the cover's ability to cool the housing.
Close up of housing, note the almost nonexistent wear pattern on the teeth of the ring gear, nice, fresh, but inevitably stinky fluid is evenly coated on everything. The teeth are sharp and the drain plug magnet had a very light bit of material on it, was easily cleaned. See that cylinder shaped pin in the center of the carrier with the yellow marking on it? That pin must be removed in order to remove the axle stubs, in a subsequent pic I'll show you what will be required in order to reinstall that pin with the different gear set.
OK, see on the top of the pin that it's not round all the way around? That's because it has been machined in order for the flat side to clear the thickness of the ring gear teeth, then rotated once in the hole in order for the retainer bolt that secures the pin to be accessed. When we install numerically higher gears, the fewer teeth on the pinion will make it smaller, making the thickness of the ring gear thicker. Hope that makes sense. So, that pin will have to be machined even further in order to be installed with the taller (thicker) ring gear. This is a normal thing to do in a situation like this. Also, the thicker ring gear is what makes longer ring gear bolts necessary. I had a pic of the dial indicator that's used to measure backlash, but it didn't come out very well. This diff was well taken care of, backlash was only .004" (4 thousandths, perfect). Backlash is the amount of slop or movement where input is made at the pinion *without* any movement output to the stubs through the assembly. Make sense? Also, since I suspect the 4.08 or 4.11 gear is from an aplication that uses smaller axle stubs (as AZHitman already posted) then the need to machine shims of the appropriate (larger) inside diameter will be required because they were made for a carrier with smaller diameter axle stubs. Easy-cheesy.
This is a pic of the mocked-up reassembled unit after tedious hours of cleaning. See that little round stub sticking out of the top right of the cover? That is a vent. When things get hot in there, pressure builds up & must be allowed to escape. It's just a little tube with a cap that rides loosely to allow the venting. Don't ask me how I did it, but I checked to see if the vent was operational by...er....creating a vacuum around the outside of it & was unable to get it to draw air through. When it arrived from the junkyard, it was upside down & fluid had leaked out of the vent. It probably got some trash in it or got bent. I will replace this piece with a new one. It's easy to install & very important. If it is clogged or otherwise non-functional, pressure will build up in there and the fluid will be forced out at the seals. Messy & unnecessary.
Not to be overconfident, but if we were to have cores as nice as this one is, there would be no need to rebuild the diff in order to do gear swaps. I think the gears are available, the shims, bolts, and machining required is doable.
This unit is going in my car as-is. My diff is totally shot & I will experiment with that one on the gear upgrade. Since I have to go through it anyway, I might as well not fool with this perfect specimen.
Diff cover removed,
Cover....blekk, covered in baked on Gra-Doo. Since the cover is aluminum & the fins are there to dissipate heat, any road grime or leaking gear oil gets baked on & reduces the cover's ability to cool the housing.
Close up of housing, note the almost nonexistent wear pattern on the teeth of the ring gear, nice, fresh, but inevitably stinky fluid is evenly coated on everything. The teeth are sharp and the drain plug magnet had a very light bit of material on it, was easily cleaned. See that cylinder shaped pin in the center of the carrier with the yellow marking on it? That pin must be removed in order to remove the axle stubs, in a subsequent pic I'll show you what will be required in order to reinstall that pin with the different gear set.
OK, see on the top of the pin that it's not round all the way around? That's because it has been machined in order for the flat side to clear the thickness of the ring gear teeth, then rotated once in the hole in order for the retainer bolt that secures the pin to be accessed. When we install numerically higher gears, the fewer teeth on the pinion will make it smaller, making the thickness of the ring gear thicker. Hope that makes sense. So, that pin will have to be machined even further in order to be installed with the taller (thicker) ring gear. This is a normal thing to do in a situation like this. Also, the thicker ring gear is what makes longer ring gear bolts necessary. I had a pic of the dial indicator that's used to measure backlash, but it didn't come out very well. This diff was well taken care of, backlash was only .004" (4 thousandths, perfect). Backlash is the amount of slop or movement where input is made at the pinion *without* any movement output to the stubs through the assembly. Make sense? Also, since I suspect the 4.08 or 4.11 gear is from an aplication that uses smaller axle stubs (as AZHitman already posted) then the need to machine shims of the appropriate (larger) inside diameter will be required because they were made for a carrier with smaller diameter axle stubs. Easy-cheesy.
This is a pic of the mocked-up reassembled unit after tedious hours of cleaning. See that little round stub sticking out of the top right of the cover? That is a vent. When things get hot in there, pressure builds up & must be allowed to escape. It's just a little tube with a cap that rides loosely to allow the venting. Don't ask me how I did it, but I checked to see if the vent was operational by...er....creating a vacuum around the outside of it & was unable to get it to draw air through. When it arrived from the junkyard, it was upside down & fluid had leaked out of the vent. It probably got some trash in it or got bent. I will replace this piece with a new one. It's easy to install & very important. If it is clogged or otherwise non-functional, pressure will build up in there and the fluid will be forced out at the seals. Messy & unnecessary.
Not to be overconfident, but if we were to have cores as nice as this one is, there would be no need to rebuild the diff in order to do gear swaps. I think the gears are available, the shims, bolts, and machining required is doable.
This unit is going in my car as-is. My diff is totally shot & I will experiment with that one on the gear upgrade. Since I have to go through it anyway, I might as well not fool with this perfect specimen.
Great write up:) When I first purchased my Q I had a fair amount of chatter, I had the diff drained and filled with AMSOIL drove it for a little while then had it flushed again, no problems since, so Heavy when do think the first units will be ready? I will be ready to purchase within the next month or so, I have gone for a spin in a 92 with the gear change and it was really sweet, as a matter of fact his car had a good 2 car lenghts on me from a 1st gear roll to about 70 or so.
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
Thanks guys!
Two lengths is pretty impressive Qckser. I was talking to my tech last night & mentioned the third gear through the traps thing to him & he said: "HELLO! that means you're covering the same amount of ground quicker!" With my upcoming larger diameter, heavier wheels, and rear tire height to be determined, I'm going to need as much help as I can get. I'm still debating a 3.80 or 3.90, but after discussing it at length, it sounds like the 4.xx is going to be the way to go.
Remember, this is AZ's deal, he's fvcking the cat, I'm just trying to hold the legs. :pface
Two lengths is pretty impressive Qckser. I was talking to my tech last night & mentioned the third gear through the traps thing to him & he said: "HELLO! that means you're covering the same amount of ground quicker!" With my upcoming larger diameter, heavier wheels, and rear tire height to be determined, I'm going to need as much help as I can get. I'm still debating a 3.80 or 3.90, but after discussing it at length, it sounds like the 4.xx is going to be the way to go.
Remember, this is AZ's deal, he's fvcking the cat, I'm just trying to hold the legs. :pface
Quote »Remember, this is AZ's deal, he's fvcking the cat, I'm just trying to hold the legs[/quote]
Thats a classic quote if I ever heard one:D
Yeah 2 cars is good, he is the reson I want to do it, with his JWT and ECU the car is a real beast, the personality of the car has been transformed, I think the only thing missing is a converter, based on the advice of another list member I contacted Pro-Tourque in NJ and was quoted $450 for a 2500-2800 stall speed, we purchased one for a friends Volvo and it should be installed next week, i think after these few modes and the addition of a 100 shot the Q will really be sick.
Thats a classic quote if I ever heard one:D
Yeah 2 cars is good, he is the reson I want to do it, with his JWT and ECU the car is a real beast, the personality of the car has been transformed, I think the only thing missing is a converter, based on the advice of another list member I contacted Pro-Tourque in NJ and was quoted $450 for a 2500-2800 stall speed, we purchased one for a friends Volvo and it should be installed next week, i think after these few modes and the addition of a 100 shot the Q will really be sick.
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maxnix
- Posts: 22627
- Joined: Mon Jul 22, 2002 8:11 pm
- Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45
Thanks for the tour, Heavy Duty! Very informative.
Think of the Torque Converter as the hydraulic "clutch" that sits between engine and transmission and allows it to slip at idle without killing it. At highway speeds, modern ones will lockup in the top gear(s), thus eliminating slip and increasing efficiency.
Look at http://auto.howstuffworks.com/torque-converter.htm .
Think of the Torque Converter as the hydraulic "clutch" that sits between engine and transmission and allows it to slip at idle without killing it. At highway speeds, modern ones will lockup in the top gear(s), thus eliminating slip and increasing efficiency.
Look at http://auto.howstuffworks.com/torque-converter.htm .
Thanks Max, nice article. I cant remember who has the gear and converter combo already, but I do remeber him saying that it worked out really nice, dgoodno for your application a higher stall speed would probably work out good, it would help on getting you back into the power band a little quicker out of the turns as would the gear change.
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AZhitman
- Administrator
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- Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
- Location: Surprise, Arizona
- Contact:
GREAT pics and writeup Jason!
You may wind up being more involved in this "cat-humping" than you think. I'll be talking with the guy in CA this week to see what he's found out.
We should discuss the possibility of your shop doing some of these to expedite things for folks. I'll have a spare core in a week or so.
Seeing your diff cover gave me an idea - Time to break out the polishing tools - There's no reason it can't look better than a chromed Jag IRS unit!
Gimme a holler this week (or this evening)?
You may wind up being more involved in this "cat-humping" than you think. I'll be talking with the guy in CA this week to see what he's found out.
We should discuss the possibility of your shop doing some of these to expedite things for folks. I'll have a spare core in a week or so.
Seeing your diff cover gave me an idea - Time to break out the polishing tools - There's no reason it can't look better than a chromed Jag IRS unit!
Gimme a holler this week (or this evening)?
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
http://www.converter.com/dragon.htm
Precision Industries is the Caddill....Mer....uh...Lex...uh...INFINITI of converters. Speak to someone who's owned a cheapie converter & you'll understand.
A-Men on the polishing, I'd rather ceramic coat it though. My local guy has a coating machine large enough to coat most shop's coating machines. Polishing would get gnarly fast, the ceramic would stay looking better longer. It shouldn't be called "coating" anyway, the ceramic stuff soaks into the metal, not on top of it.
Precision Industries is the Caddill....Mer....uh...Lex...uh...INFINITI of converters. Speak to someone who's owned a cheapie converter & you'll understand.
A-Men on the polishing, I'd rather ceramic coat it though. My local guy has a coating machine large enough to coat most shop's coating machines. Polishing would get gnarly fast, the ceramic would stay looking better longer. It shouldn't be called "coating" anyway, the ceramic stuff soaks into the metal, not on top of it.
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maxnix
- Posts: 22627
- Joined: Mon Jul 22, 2002 8:11 pm
- Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45
Dgoodno and those interested in the forced induction upgrade, and even those in hot states, may want to consider how to add a differential cooler and the required pump. I think the Z32 had such an option, along with a PS cooler (attention dgoodno).__________________Brian1995 Q45 & Q45t & 2000 Q45
Discover the power of the button!
Discover the power of the button!
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HeavyDuty
- Posts: 1281
- Joined: Tue Sep 23, 2003 4:51 pm
- Car: 1995 Infiniti Q45
95 Nissan 240SX S14
96 Nissan D21
06 Nissan 350Z Z33
Michael's Auto Parts in Orlando, Florida has 2 or 3 more 94-96 rear diffs.
407-423-1695 x 207 ask for Vinnie. (Straight outta da Bronks Vinnie, you'll know if he answers the phone)
Also, I'm home so I can't look at my parts disc, but would someone please look to see if there's any differences in part numbers for the viscous assembly from a 90-93 and 94-96.
My FSM shows a viscous coupling for my 91. This 94 diff I have feels like it has a ratcheting type LSD.
I'll know more when I pull my original 91 apart, just curious now.
407-423-1695 x 207 ask for Vinnie. (Straight outta da Bronks Vinnie, you'll know if he answers the phone)
Also, I'm home so I can't look at my parts disc, but would someone please look to see if there's any differences in part numbers for the viscous assembly from a 90-93 and 94-96.
My FSM shows a viscous coupling for my 91. This 94 diff I have feels like it has a ratcheting type LSD.
I'll know more when I pull my original 91 apart, just curious now.
DKILL I have about $350 worth of stuff from yahoo jp, JDM headlights with clear markers (Max dont yell at me:) ), the factory bumper lights with the little bubble, and waiting for my grill to get shipped, even purchased a REAL NISMO oil cap, if you want the info you can either call me or I will call you, doesnt matter its just too much to explain by typing:)
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AZhitman
- Administrator
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- Joined: Mon Apr 29, 2002 2:04 am
- Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
- Location: Surprise, Arizona
- Contact:
1qck - Hit me up via cell as well - 602-828-8908. I have a question about a few goodies.
Jason, any idea what "Vinnie" will give us the diffs for if we buy all he can provide? If the price is right, I'll take 'em for the group buy.
Sorry I didn't call back later - Mama had lots of stuff to tell me. Had a good time rapping with you, gimme a holler this week when you're not too busy?
Jason, any idea what "Vinnie" will give us the diffs for if we buy all he can provide? If the price is right, I'll take 'em for the group buy.
Sorry I didn't call back later - Mama had lots of stuff to tell me. Had a good time rapping with you, gimme a holler this week when you're not too busy?
Oh, is the transmission the same for the 94 and 96? I have two 96, maybe I will just stock the rebuit 94 and find a core somewhere. I really need to get Tony back online. He had said he would be on early in the rear end discussion, but have not seen him -- nor heard yet his recommendation on what ratio to go with. I'm inclined to max it out.
Precision Industries (purple color) supply some Torque Converters to Level 10. I assumed that they also supplied the Torque Converter for the Q45 to level 10 who just painted it yellow and wacked on their %.
I asked Sam Ismail is this was the case and he said NO, Level 10 build there own in a workshop next door.
It may be worth ring and checking to see if you get the same info as me.
If level 10 do the whole transmission, including the Torque converter, it may make any warranty issues ect easier.
Regards
AGM
I asked Sam Ismail is this was the case and he said NO, Level 10 build there own in a workshop next door.
It may be worth ring and checking to see if you get the same info as me.
If level 10 do the whole transmission, including the Torque converter, it may make any warranty issues ect easier.
Regards
AGM