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Neo Turbo Engine In My Na R34 Gt

bra0063

By bra0063,
in Engines & Forced Induction

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N-DAWG Mentor

N-DAWG

Posted
Posted

GT Gearbox won't last long with increased power. Any little-to-mild flaring issues will become much more noticable very quickly.

I ended up going down the rebuild path with my gearbox in the end with HD Kevlar Clutchpacks, HD Bands, new solenoid set, and valve body upgrade. Handles it like a dream since. BUT that cost $3300 and if I did it again I'd get a low-mileage R34 GTT Box and valve body it.

N-DAWG Mentor

N-DAWG

Posted
Posted

Advice I was given by the performance auto specialist was a valve body can either improve and strengthen, or make worse and weaken an auto box. My auto was flaring quite bad, adding extra power didn't help. Third gear wasn't in a good state. A valve body upgrade would have just done it a lot worse and prematurely ended the gearbox.

Get a low mileage Auto GTT Box in good nick, do the valve body upgrade, and done! If you plan to give it on the track invest in a transmission cooler and temp gauge. I haven't done so yet myself, but that's just purely down to funds. Heat kills autos, more power = more heat... you do the math.

btw, I've just ordered an R34 GTT Front Cut Including Loom etc.. minus the GearBox, and sourced an Auto GTT ECU.

Hopefully next week or so the mechanic will be ready to do the swap and I can shed more light on the issues that arise or may not arise... But as stated before, gearbox will definitely be your first weak link when increasing power so if you haven't rebuilt your gearbox (expensive job!) try and get a half cut including gearbox and do a valve body upgrade.

Not wanting to be a thread hijacker here... but while this is on the topic of dropping a neo turbo engine into a N/A Neo: what is the difference between the wiring loom and ECU pinouts between the RB25DE NEO and RB25DET NEO? Reason being I currently have a Piggy Back eManage and would like to be able to transfer that accross to the new ECU without re-wiring the entire unit, obviously to save money. Would using an existing loom be ok, or is it going to be a case of change loom, change ECU and resplice the eManage harness on likely the same wires? That wouldn't be so bad...

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