Jumbo's Transmission thread

Here is one of the only TT AWDs I know of. http://g35driver.com/forums/forced-...b-fcon-vpro-custom-td-methanol-injection.html

He blew his stock trans a little bit after getting it back from GTM. He had an upgraded trans fluid cooler, albeit not very big.

Input tq is what will determine what a transmission can take, lots of low tq from say small TT set up applies a lot of input tq low. The vast number of long lasting boosted 5ATs are going to be centrifugal supercharger since the low end torque is not altered very much, boost is built with rpm.
 
I guess there's gotta be FX trailblazers too. I'm definitely doing the full build, with upgraded cooling (thermostat & fan on bar/plate cooler) and my car is Rear wheel drive. I'd really prefer the turbo as compared to the supercharger, for power capability, fuel efficiency and adjustability reasons. Just a personal preference since money isn't really the issue.

I totally understand I'll be taxing the built 5AT at the upper end of the 450-550 whp range, but not often or for long periods. Just fun driving in my everyday car. It's not a track car or a drag car, though I could see doing that once in a while just to have fun and feel out all the benefits of the time and money I have put into my FX.

The mods I make are always with a bigger picture in mind. I'm asking you guys on the forum if you believe I'm getting there with the choices I'm making for Jumbo's application. I hope I'm describing that big picture clearly, and you guys are asking good questions - some of which have changed my previous choices. That's why I joined IS - so keep the comments coming and thanks so much for all of your help!
 
Min, lebron23 was built motor TT a while back. Ended up blowing his transmission up, I sold him my spare trans.

Issafx built motor TT as well. Not sure if you can see the thread unless reg. http://my350z.com/forum/cars-for-sa...-2003-infiniti-fx35-with-jwt-twin-turbos.html
2003 Infiniti FX35 with Twin Turbos:

Jim Wolf Technology (JWT) Twin Turbos with intercooler
Built engine with GTM Turbo Cams, Pauter rods, valves springs, pistons and
bigger injectors (8.5:1 Compression)
Walbro 255 fuel pump
HKS F-CON V-Pro with Navigator
Technosquare flash
Koyo Radiator
GTM Radiator Fans (14") with custom shroud
Motordyne 1/2" ISO Plenum Spacer and MREV2 Manifold
Fluidampr Harmonic Pulley
Greddy catch can
Higher Stall Torque Converter
Transmission cooler
Nismo/Fujitsubo catback exhaust with custom tips
Fast Intensions (F/I) Hi-Flo 300cell metallic Cats
Gauges
iForged Aero 20x10 wheels
Sway Bars (2 front & 1 rear)
Eibach Suspension Lowering Kit (front & rear)
StopTech Stage2 Slotted rotors (front & rear)
Stainless steel brake lines (front & rear)
LoJack
K&N XStream air filter pulling cold air from behind driver side fog light
Immobilizer ignition kill switch (works but needs more configuring)
Heavy duty battery
11.3" DVD entertainment system
JBL 500watts amp with Alpine X-Type sub in a sealed box
Sport clear tails and headlight covers
Under dash and seats UV "black" LED lights.
New Continental CrossContact UHP 295/45ZR20 all around
New EBC Yellowstuff brake pads all around
Newly built GTM Performance Tranny with new GTM modified valve body
Misc. & support items: Momo shifter, Georgia rug masters, wood kit, blue lit
door sills, tint, painted grill, back reflectors and brake light overlays, side mirrors
with turn signal shells, after market fogs with angel eyes, dark chrome Infiniti
emblems front and back, rear-spoiler, etc.

One owner title in hand

Mileage: 63K miles.
Color: Black on black

GTM Dyno'ed @ ~415wtrq and ~398whp on 91 gas with 20x10 wheels.

Transmission ended up slipping or what not.

There is Also AusFX in Texas, had the JWT 530BB on his RWD FX done by SGP racing a while back. I met him at HIN Austin last year.

In Taiwan, a TT was put onto a FX35 a LONG time ago. Even ahead of me here in the US. They ended up having a slipping trans so they put it back to stock and traded it in.
 
Viet, so you are telling me I shouldn't expect to tune to more than 400 from the TT, before the transmission slips? You think it would even be an issue for my planned use/driving style?
 
400whp load on the trans or whatever derivative hp you get from the tq, is like 450 on a G/Z due to our drivetrain and 20+lbs more per corner wheels.

This is copy paste.
All torque is, is the amount of twisting force the engine can exert. Horsepower is the amount of twisting force, correlated against the rpm at which that force occurs. There is a crossover point at 5250 rpm where torque and horsepower are exactly the same number.
Click to expand...
HPx5250/RPM=TQ and vice versa

Say stock you make 150hp x 5250 / 4k rpm this is 196TQ
Most smaller TT will be full at boost by 4k. Let's just say it doubles the hp. 300hp x 5250 / 4k rpm 393TQ

Here's an old dyno of mine. TQ scale on the right is not the same as the HP scale on the left.
View attachment 172390

Compare this to the recent FX Vortech build.
View attachment 172392

If you want longevity, and have a "HP" goal, you're better off with a supercharger. The huge inrush of TQ from a turbo is a lot to ask of the 5AT.
 
I understand the TQ vs whp relationship and calculations, but I'm trying NOT to accept what you are telling me! Again, you are saying that my newly built 5AT won't take much more than 400?

I have not seen more than one or two people on the forum here put out over 400 with a supercharger. Chinke82's Vortech might be the first I can recall. Stillen S/Cs do not make over 400 on the FX, do they?
 
chinkes Vortech is the only one I've seen make over 400 on a sc. There was another Vortech FX a long time ago in Florida, the guy was selling the kit on ebay.

I'm not sure you're getting what I'm saying. Peak hp and the peak tq are 2 very different things. The tq converter is basically a pump, the faster it spins the more fluid is being pumped. Having the power curve of a centrifugal supercharger is much less abusive than a turbo.

A rebuilt trans is a good thing. I made 500+, and it took massive amounts of boost because the 5AT effeciency continues to go down. Some of the 5AT builds out there with built transmissions stop for a reason, the tuners don't want to blow the owners transmissions, or leave the tune at a level where they are seeing diminshing returns when raising boost.

http://my350z.com/forum/shop-builds...ed-622rwhp-600rwtq-gtm-5a-t-track-tested.html
600+ 4.2L motor, read this post. http://my350z.com/forum/4781170-post47.html

Making a number on a dyno and using it are 2 different things. Roncpfz also has a GTM built 5AT, he stopped his power in the 500-550 range as do most others out there.

What I'm basically saying is, don't have a hp goal. One of your goals was longevity, and reliability without sacrificing it being a "normal" car.
 
Ok, I get it.

When you say some builds, "stop for a reason", what do you mean? They give up and go back to OEM parts? Or they just level off the build and stop trying to go higher than the transmission limit?

I do hope to keep longevity and driveability, with a TT setup. Again - normal every day driving car. Maybe I'll challenge somebody off the line a few times a year, or push it on the highway when I have an open stretch of empty road - but that's all the demand it will see. I can't imagine I'd be hurting the 5AT with the compliment of modifications I have. Do you?

Couldn't an aftermarket engine management computer (and a good tune) be used to limit fuel maps or RPMs in the low end just to protect the transmission, when running a TT? If we can remove limits, why can't we impose them also? I know this could be another thread, but it's also in the spirit of protecting THIS transmission.
 
You received a lot of good information here and I hope it helped you make a informed decision. Good luck with this and let us know how everything goes.
 
I completely agree. The info I learned on here was absolutely necessary to deciding what I was going to have done. Thanks again to all.

I just dropped off the car and the shop had recently completed a Greddy Turbo G35. Had it there for me to take a look at. They did the same transmission work for the G35 and they are putting up numbers on the dyno around 625.

So far communication has been really good with these guys. Hopefully that continues through the build. I gave them permission to take pictures and to use them on their site.

If they send me anything, I'll be sure to post!
 
jumbosrule said:
I completely agree. The info I learned on here was absolutely necessary to deciding what I was going to have done. Thanks again to all.

I just dropped off the car and the shop had recently completed a Greddy Turbo G35. Had it there for me to take a look at. They did the same transmission work for the G35 and they are putting up numbers on the dyno around 625.

So far communication has been really good with these guys. Hopefully that continues through the build. I gave them permission to take pictures and to use them on their site.

If they send me anything, I'll be sure to post!
Click to expand...


I just checked their website. I hope you are aware that the g35 is a stick and not a 5at right? In the picture that they have of the g35 with greddy it CLEARLY shows an aftermarket clutch... not trying to bash or anything bud. Just dont expect that kind of performance (serious slipping) with just a transgo kit and tc. On a side note though... i cant wait for your build to finish since you also live in houston.

edit: forgot to add link to pic of their g35
http://www.unleashedautosports.com/Project_Infiniti.htm
 
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Remember, also doing upgraded internals and cooling.

Talked to the shop tonight, the parts are due in tomorrow, so I won't be able to pick up. But he thought there was a good chance for Sunday, which is great. I don't get it for the weekend, but I'll get to drive it to work!
 
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Transmission done

The guys at Unleashed worked through the weekend to finish it up. Picked it up around 3pm on Sunday and took it for a drive.

I immediately noticed the shifts were more crisp - not at all in a bad way. The shifts are still really smooth between gears. In fact, the overall feeling is just a bit more, "peppy". It seems to respond more quickly to throttle and it feels more open and easy during acceleration. This change in feel is definitely due to the shift kit and the upgraded internals. HOWEVER - I made a pretty cool observation. Because I went with a shift kit and NOT a Valve body upgrade, the transmission's ECU is still stock. I was totally happy to find that the core shift feeling of the FX was still there - just better.

The Torque converter mod (stock core) is barely noticeable during normal driving - it seems to hang on for just a fraction longer before shifting at low speeds. Again, I chose to use the stock core instead of a direct replacement, to keep the FX feel, which I think I did. At WOT, the gear stays engaged quite a bit longer (shifted into 3rd gear at 70mph) The guys at the shop said the TC mod will be virtually transparent until I go for FI. Then the higher stall will be felt more. I feel it now when I push it. Normal driving - it just feels a little tighter, a little quicker.

The B&M cooler was front mounted to the right side of my radiator, with the fan on the front (behind the grill). So far I'm not even sure the fan has come on. It might not until I start stressing out the transmission. For now I am still NA so the current upgrades should make the transmission coast through anything I can throw at it.

I'm totally happy with the performance and feel so far. My feeling is that this is not a mod that gives you a huge bang for your buck. The Intake, exhaust, plenum spacer - all FELT like equal impacts to performance feel compared to this mod (just for much less cash), which I totally understand. But if I really want that FI eventually, then this is the best way to make sure I can take advantage of the power the engine puts out. Plus, my stock tranny had 96000 miles on it. Now, it's pretty much new. Don't get me wrong, I'm not downplaying the end result. I'm glad I did it, and I'd do it again. I'm pretty sure I could take any stock FX with this mod alone. It wouldn't be a blow out, but the more agressive gearing is just better than the stock acceleration curves. The trade off will be mpg. Not a huge impact, but there for sure.
 
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