safest Forced Induction on a 5at?
#17
08-01-2006 | 01:09 PM
Originally Posted by Q45tech
ALL AT transmission are rated by TORQUE CAPACITY in the case of G35 it is 333 lb/ft peak. 333/260= 28%/6.8 [1.0psi equivalent] = ~~4.0 psi [temperature corrected to 60F] max at where ever torque peak rpm occurs [4400].
Normally a 6 psi radial supercharger creates no more than 1.5 -2.5 psi at 4400.........luckily some of the engine torque goes to drive the supercharger [20-25 lb/ft] so this provides additional safety.
Normally one would expect 150,000 miles from a well maintained averagely driven 5AT...........exceeding the torque standard frequently will of course reduce life by a 4 to 16 factor.
Because to always have a [ebay junkyard JDM] spare on hand as from the dealer the unit will run $3,500+
Normally a 6 psi radial supercharger creates no more than 1.5 -2.5 psi at 4400.........luckily some of the engine torque goes to drive the supercharger [20-25 lb/ft] so this provides additional safety.
Normally one would expect 150,000 miles from a well maintained averagely driven 5AT...........exceeding the torque standard frequently will of course reduce life by a 4 to 16 factor.
Because to always have a [ebay junkyard JDM] spare on hand as from the dealer the unit will run $3,500+
BTW, I noticed that you're in the same town as Forged Performance - you guys know each other or work together? Just curious...
#19
08-01-2006 | 02:53 PM
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Joined: Dec 2003
Posts: 2,514
Likes: 4
From: Marietta, Georgia
JATCO has it's own internal standards since they must now assume the cost of a failed AT [warrantywise] they warranty the part to Nissan.
You should find and read the English version of JATCO TransTechnology Review 2001 # 2 which covers the design and testing of the JR507E
As you see from the following the same tranny is used for V6 and V8 at least up to 4.5 liters thus the 333 lb/ft limit.
http://www.answers.com/topic/list-of...-transmissions
4-16 just a mechical engineering rule of thumb for overstress of rotating components................why would anyone bother the build an engine to see when a tranny explodes.
We do know from Nitrous experiments that a 75 hp [jet] [~~100-120 lb/ft] bump up trashed a few RE4R03A [rated at 292 lb/ft] in short order yet a mild 10% ....30 lb/ft/30 HP ecu mod with loud exhausts seem not to affect 100,000 mile life.
My guess is 10% ok but 20% increase could start to cause problems........why I chose 375 lb/ft as limit.
Modern finite analysis [super computer] has allowed engineers to shave weight and strength to increase mpg while cutting out excess strength without warranty concerns.
There is little safety in current designs unlike old make it stronger so it won't fail of the 1990's.
You should find and read the English version of JATCO TransTechnology Review 2001 # 2 which covers the design and testing of the JR507E
As you see from the following the same tranny is used for V6 and V8 at least up to 4.5 liters thus the 333 lb/ft limit.
http://www.answers.com/topic/list-of...-transmissions
4-16 just a mechical engineering rule of thumb for overstress of rotating components................why would anyone bother the build an engine to see when a tranny explodes.
We do know from Nitrous experiments that a 75 hp [jet] [~~100-120 lb/ft] bump up trashed a few RE4R03A [rated at 292 lb/ft] in short order yet a mild 10% ....30 lb/ft/30 HP ecu mod with loud exhausts seem not to affect 100,000 mile life.
My guess is 10% ok but 20% increase could start to cause problems........why I chose 375 lb/ft as limit.
Modern finite analysis [super computer] has allowed engineers to shave weight and strength to increase mpg while cutting out excess strength without warranty concerns.
There is little safety in current designs unlike old make it stronger so it won't fail of the 1990's.
Last edited by Q45tech; 08-01-2006 at 03:08 PM.
#22
08-02-2006 | 07:18 PM
#23
08-03-2006 | 11:14 AM
Registered User
Joined: Dec 2003
Posts: 2,514
Likes: 4
From: Marietta, Georgia
I'm nowhere near that torque.
Say what don't confuse rwheel dyno torque with the TC shaft input [flywheel spec]
266 rear lb/ft times 1.22 = 325 lb/ft at the TC input shaft yep that's cutting it close to a 333 lb/ft maximum input.........
The problem is the tranny expects the lb/ft to decline as the rpms increase above normal torque peak with a supercharger [anykind] the psi boost sustains the torque into the 6,000 rpm range.
310RHP@6,000 5252/6000=0.87 x 310= 270 ~~266 [per your report] x 1.22....again 325 lb/ft.................it's the flatish torque curve that did you in.
Keep us informed as to if you get 100,000 gear shifts. Not sure how many WOT shifts is the equivalent of an average school teacher shift at 20% power.
Maybe only ONE drag race per month [7 x12 = 84?] Keep a written record and examine ATF monthly [color on white paper towel, smell, taste] that way you can better guess when to order a new AT so it's on hand.
I'm on my 3rd RE4R03A [60k, 235k].......I learned the 1st time how to triple the life of the second unit. Annual [20-25k] fluid replacement, filter changes, big auxillary cooler, and an accurate ATF sump temperature gauge with warning light at 190F.
Happy shifting!
Say what don't confuse rwheel dyno torque with the TC shaft input [flywheel spec]
266 rear lb/ft times 1.22 = 325 lb/ft at the TC input shaft yep that's cutting it close to a 333 lb/ft maximum input.........
The problem is the tranny expects the lb/ft to decline as the rpms increase above normal torque peak with a supercharger [anykind] the psi boost sustains the torque into the 6,000 rpm range.
310RHP@6,000 5252/6000=0.87 x 310= 270 ~~266 [per your report] x 1.22....again 325 lb/ft.................it's the flatish torque curve that did you in.
Keep us informed as to if you get 100,000 gear shifts. Not sure how many WOT shifts is the equivalent of an average school teacher shift at 20% power.
Maybe only ONE drag race per month [7 x12 = 84?] Keep a written record and examine ATF monthly [color on white paper towel, smell, taste] that way you can better guess when to order a new AT so it's on hand.
I'm on my 3rd RE4R03A [60k, 235k].......I learned the 1st time how to triple the life of the second unit. Annual [20-25k] fluid replacement, filter changes, big auxillary cooler, and an accurate ATF sump temperature gauge with warning light at 190F.
Happy shifting!
Last edited by Q45tech; 08-03-2006 at 11:17 AM.
#25
08-03-2006 | 08:18 PM
Registered User
Joined: Dec 2003
Posts: 2,514
Likes: 4
From: Marietta, Georgia
#26
08-03-2006 | 09:12 PM
Originally Posted by Q45tech
I'm nowhere near that torque.
Say what don't confuse rwheel dyno torque with the TC shaft input [flywheel spec]
266 rear lb/ft times 1.22 = 325 lb/ft at the TC input shaft yep that's cutting it close to a 333 lb/ft maximum input.........
The problem is the tranny expects the lb/ft to decline as the rpms increase above normal torque peak with a supercharger [anykind] the psi boost sustains the torque into the 6,000 rpm range.
310RHP@6,000 5252/6000=0.87 x 310= 270 ~~266 [per your report] x 1.22....again 325 lb/ft.................it's the flatish torque curve that did you in.
Keep us informed as to if you get 100,000 gear shifts. Not sure how many WOT shifts is the equivalent of an average school teacher shift at 20% power.
Maybe only ONE drag race per month [7 x12 = 84?] Keep a written record and examine ATF monthly [color on white paper towel, smell, taste] that way you can better guess when to order a new AT so it's on hand.
I'm on my 3rd RE4R03A [60k, 235k].......I learned the 1st time how to triple the life of the second unit. Annual [20-25k] fluid replacement, filter changes, big auxillary cooler, and an accurate ATF sump temperature gauge with warning light at 190F.
Happy shifting!
Say what don't confuse rwheel dyno torque with the TC shaft input [flywheel spec]
266 rear lb/ft times 1.22 = 325 lb/ft at the TC input shaft yep that's cutting it close to a 333 lb/ft maximum input.........
The problem is the tranny expects the lb/ft to decline as the rpms increase above normal torque peak with a supercharger [anykind] the psi boost sustains the torque into the 6,000 rpm range.
310RHP@6,000 5252/6000=0.87 x 310= 270 ~~266 [per your report] x 1.22....again 325 lb/ft.................it's the flatish torque curve that did you in.
Keep us informed as to if you get 100,000 gear shifts. Not sure how many WOT shifts is the equivalent of an average school teacher shift at 20% power.
Maybe only ONE drag race per month [7 x12 = 84?] Keep a written record and examine ATF monthly [color on white paper towel, smell, taste] that way you can better guess when to order a new AT so it's on hand.
I'm on my 3rd RE4R03A [60k, 235k].......I learned the 1st time how to triple the life of the second unit. Annual [20-25k] fluid replacement, filter changes, big auxillary cooler, and an accurate ATF sump temperature gauge with warning light at 190F.
Happy shifting!
Great information as always. I'll start logging. After I installed the tranny cooler I started to weekly give the tranny fluid an eye and smell test. So far it's still nice and red smells a little sweet but not burnt. Is that normal? Also what are the fill lines? Between the 2 notches or in the criss-crossed area at hot temp?
Geez this sounds like a man has so many ejaculations before....
Last edited by Xman; 08-03-2006 at 09:36 PM.
#28
08-11-2006 | 08:05 AM
Registered User
Joined: Feb 2005
Posts: 36
Likes: 0
From: Philly
An interesting discussion,but the ECU drops 3 cylinders on every shift to reduce the torque the trans sees
Additionally,there is a rebuild kit coming which adds an extra clutch and steel and better friction material for additional torque capcity(the prototype is going in my FX as I write) so there will be life for these higher cpacity motors
Lastly the 200 trans in my GN was technically rated at 200 torque so the HP of that 3.8 turbo motor was printed at 235.We raced that trans at well over 500 hp and matching torque and the trans lived
Additionally,there is a rebuild kit coming which adds an extra clutch and steel and better friction material for additional torque capcity(the prototype is going in my FX as I write) so there will be life for these higher cpacity motors
Lastly the 200 trans in my GN was technically rated at 200 torque so the HP of that 3.8 turbo motor was printed at 235.We raced that trans at well over 500 hp and matching torque and the trans lived
Last edited by brnjug; 08-11-2006 at 08:10 AM.
#30
08-11-2006 | 10:31 AM
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Joined: Jul 2003
Posts: 250
Likes: 0
From: Eau Claire, Wisconsin
Depending on one's perspecive, I have either the misfortune or good fortune to have the 5AT. Other than the fact that the shift handle moves towards the passenger side to access the manumatic (what doesn't fit in this picture?) I really love the tranny and find it shifts much better than any stick I've driven.
Unfortunately, it does appear to be another obstacle (in addition to the engine) to achieving a reliable TT setup. I've done a bunch of research and at this point, the Level Ten route is the one I would choose to bullet proof the tranny.
The short story is that their complete upgrade runs about $5K, including shipping both ways, and of course includes VB, torque converter, and clutch pack upgrades. They tell me that this upgrade on the Nissan/Infiniti tranny will hold anything thrown at it and to date, they have never had even one fail.
I've spent some time talking to them and personally find them believable. But more importantly to me, when I have mentioned competitors, they have never bad-mouthed anyone. Their line has been simple, "We specialize in performance trannys, that's all we do, and we know how to do it right".
I've also done a considerable amount of internet research on them and they come up as clean as any other vendor. Occasional folk seem to be able to come up with rumors and buddy stories about anyone, but there certainly is no trail of horror stories or dissatisfied customers that I could find anywhere.
Based on what I have learned, they are the ones I would currently choose to build my tranny if I wanted it to hold over 400WHP.
Unfortunately, it does appear to be another obstacle (in addition to the engine) to achieving a reliable TT setup. I've done a bunch of research and at this point, the Level Ten route is the one I would choose to bullet proof the tranny.
The short story is that their complete upgrade runs about $5K, including shipping both ways, and of course includes VB, torque converter, and clutch pack upgrades. They tell me that this upgrade on the Nissan/Infiniti tranny will hold anything thrown at it and to date, they have never had even one fail.
I've spent some time talking to them and personally find them believable. But more importantly to me, when I have mentioned competitors, they have never bad-mouthed anyone. Their line has been simple, "We specialize in performance trannys, that's all we do, and we know how to do it right".
I've also done a considerable amount of internet research on them and they come up as clean as any other vendor. Occasional folk seem to be able to come up with rumors and buddy stories about anyone, but there certainly is no trail of horror stories or dissatisfied customers that I could find anywhere.
Based on what I have learned, they are the ones I would currently choose to build my tranny if I wanted it to hold over 400WHP.