Tiny bit of background....I have an 05 G35x that I use to drive everywhere (some snow in Idaho), and a 94 Supra single turbo that I like to drive in the spring-fall and take to track days. But I end up having 3 adults in the car frequently, and as such the Supra almost never gets driven as much as I'd like. I love the G35x for all weather driving and comfort for 3, and I'm trying to figure out how to marry the two, or if it's even possible. In the end I'd like to create a G35x with ~450-550 hp. I've searched the forums and still have a number of questions. Here goes....

1) Engine
With so many parts available for the VQ, engine internals seem like the simplest part of the conversion. However, tuning fuel/ignition maps could be harder. I haven't seen any reflashes for the X's ECU yet. Though several people seem to have piggyback setups working nicely. I imagine the fuel systems other TT coupes/sedans are running will work equally as well for the X.

2) Turbochargers
I only see superchargers on the modified X's. The APS twin kit looks like it would fit in the X.....does it interfere? The front diff looks to be the main source of potential interferance, but it's too close for me to tell from the images on the company web site. They're advertising it works with the RWD auto, and the driveshaft is so close to the tranny that I can't imagine that interfering. Any insights you have would be appreciated

3) Transmission
I see Stillen makes a valve body upgrade for the auto, and it's the same as used behind the 4.5 V8. That could be an option....but I'd *really* prefer a manual tranny. Obviously the 6 spd will not bolt up to the transfer case, but it would bolt nicely to the block, and the shifter would fit using all factory trim from a 6 spd car. And getting the pedal setup from a 6 spd car would help maintain factory parts. Does anyone have measurements on the length of the 6 spd tranny? My auto is ~30.5" from engine block to t-case. I'm just exploring the possibility of replacing the tranny output shaft and adapting from the 6 spd tail shaft to the X's t-case. I don't have any images of the 6 spd from the G35 though, so this whole thing may not work. I'm mostly concerned about the shift linkage interfering with the t-case. Possiblility of other transmissions working? Nothing about that swap would be trivial...I'm just wondering if it's even spatially possible.

4) Suspension
yeahdickey just posted details about the X's spring rates yesterday
https://g35driver.com/forums/g35-sedan-v35-2003-06/95880-x-spring-rates-finally-known.html
Currently, options are limited, but I'm sure more will open up. For ride height I can invision something H&R's threaded rear perches.

There was also a recent post about the Cusco anti sway bar's working on the X, but I'm suspicious.....
https://g35driver.com/forums/brakes-suspension/95658-install-cusco-sway-bars-g35x-help.html

5) Brakes
Even though the brake problem was supposed to be fixed in 05, apparently the X's still have the same brakes as before (fixed in 06???) I don't know how compatible the front uprights (caliper mounts) of the X are with the RWD cars. Does someone make a kit to use the track Brembo's? Or is Stoptech making caliper/rotor kits for the AWD? Any info here is also appreciated.

6) AWD system
I've read that the X uses the same AWD system as the non-V-spec R34. But I don't know how related they are (same software? same hardware?). I haven't heard about any of the other supercharged X's having trouble with their t-case or front diff. Is this an area for concern? Will the torque split still be 25% F for launch, 50% snow mode? This may be a moot point since snow/launch are all low speed, and the engine wouldn't be making much more torque than stock anyway. Clearly the AWD system on R34's adapt nicely with increased power. Just don't know what to expect with the X's.

Any help or insights would be appreciated. I'm loving the X as a daily driver, and the chassis seems like a great platform for some occasional track use as well. Or, if I'm totally out to lunch I'd like to know that too. I love the idea of a great all season track-worthy car that can seat 3 comfortably for a moderate distance drive...but it could be that's just too much to ask of a single car.

Thanks in advance-

-Dan

 

Good post with a lot of good questions. Hard to find a lot of answers. For me it's an experiment. I went conservative with a vortec set up but I'm sure that you can get at least a ST in there. It's been done for an FX35 as far as I know. For the hp that you want I think you'll definitely need to beef up your tranny either SGP or ProTorque. I stayed stock after the vortec install and blew the tranny in about a month. Right now I'm getting a low mileage tranny and getting an SGP VB and level 10 TC upgrade. I haven't done much with the brakes yet except throwing on Hawk pads. As far as I know there's only me and powerhousefan that went FI with our Xs. It would be good to have more of us to share the info.

 

Thanks for the info Xman. Based on how little I was able to find I wonder if it's a little early for much to be released for the X. Only the first cars are starting to come out of waranty. I'm mostly trying to figure out if the lack of performance parts is because they're relatively new, or if no aftermarket companies seem to believe there's a performance market for the X.

That's a bummer about your tranny. I would have thought the tranny would hold up to mild boost, but now we know otherwise. SGP looks to be making some serious upgrades for the tranny though, so that's good. Site says they're working on one that will handle 850 WHP!!

I'll keep searching and post info in this thread as well.

I did see recently that one Japanese tuner (can't remember exactly which one off hand) build a G35C with a twin turbo 4.5L V8 and was using a Supra TT transmission behind it. I should take some measurements on my TT tranny :o) That would be a MAJOR pain to swap on both ends (engine and t-case).

Thanks again -

-Dan

 

It's been hard to finf options for X.

Even teh OEM Chin are not suppose to fit teh X, I put it on anyway.

I've got Wilwood 13.6" brakes. Stillen Dual. Z tube.

Stillen SC won't fit because there's no Hood for 05 SEdan.

Thinking about HKS SC at some point, hope to be safer than Vertex