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Ive recently bought a R34 Gt non turbo coupe and decided that it could do with a turbo, however after a little research I've found that turbo'ing a Rb25De motor is a pain in the ass and has quite a few problems. From my knowledge the primary reason that a Neo De motor cant be turbo'ed efficiently is due to its high compression pistons (correct if wrong) therefore is it possible to buy a complete De motor and put low compression pistons in? Basically can I build a GTT motor from a Non turbo block or is there something else that I'm missing or other things involved.

Thanks heaps.

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Yep. You are missing brakes, gear box, diff, legally registered etc.

It's been said time and time again, including by people that have done it, it is not worth it. Buy a gtt.

Also a De neo has smaller head ports and tiny cams, and long with different inlet manifold and plenum. Not just the pistons are different. Buy a gtt.

Ive recently bought a R34 Gt non turbo coupe and decided that it could do with a turbo, however after a little research I've found that turbo'ing a Rb25De motor is a pain in the ass and has quite a few problems. From my knowledge the primary reason that a Neo De motor cant be turbo'ed efficiently is due to its high compression pistons (correct if wrong) therefore is it possible to buy a complete De motor and put low compression pistons in? Basically can I build a GTT motor from a Non turbo block or is there something else that I'm missing or other things involved.

Thanks heaps.

It will be cheaper and quicker for you to buy a GTT; than to do an engine transplant, plus all the extra needed upgrades as mentioned above. Plus the wiring looms are different. Save your money and buy one already turbo'd.

you can keep asking untill someone sais its a good idea, but its not.
sell the na, take your 2k maby save a bit more (less that its about to cost you) and buy a gtt.

buy a gtt

BUY A GTT

BUY A GTT

And if I bought a GTT engine with loom and ecu would it work, because I can drop one in for under 2k and that'll save me spending 10k+ on a Gtt

What about brakes gearbox diff and legalities? That will blow your budget to bits.

I dont care about the brakes, its a auto and as it'll be racing primarily in a straight line its staying an auto, and whether its legal or not I could care less I just want to know if I can put a GTT motor in a GT, not whether I should buy a GTT, rephrase 'Can a GTT engine and loom be connected to the existing R34 GT and run, not including support mods or legalities, can it bolt up and run as a turbo motor'. Its just as a project car its mainly sitting around I can worry about the diff and brakes later when its ready to be driven, Its whether it will bolt up to the existing structure have all the turbo piping connected and running so I can turn the key start the car and move it around my property?

I dont care about the brakes, its a auto and as it'll be racing primarily in a straight line its staying an auto, and whether its legal or not I could care less I just want to know if I can put a GTT motor in a GT, not whether I should buy a GTT, rephrase 'Can a GTT engine and loom be connected to the existing R34 GT and run, not including support mods or legalities, can it bolt up and run as a turbo motor'. Its just as a project car its mainly sitting around I can worry about the diff and brakes later when its ready to be driven, Its whether it will bolt up to the existing structure have all the turbo piping connected and running so I can turn the key start the car and move it around my property?

I had a na (not my choice) that I turned into a fully built auto everything

in short, buy gtt

Simply looking at the stuff on a GT, vs whats REALLY on the GTT you will buy a GTT. There's differences in little things all over the place.

Sell NA to a P plater.

Buy GTT.

It is the smartest thing you will ever do.

  • Like 2

thats not what you asked,

you stated you have a gt which you want to put a gtt engine into.

your intentions are to drag race it and hope to do this to save money instead of selling up and buying a gtt.
this will not work, it will not be cheaper and you will still not have a gtt.

if you want to do it just do it. however you can't ask for opinions just to get a unanimous answer backed up by experience, then get annoyed that no one is in agreance with your plans validity.

Edited by GH05T
  • Like 1

Pretty much anything with 'swap' or 'conversion' in the title is not worth it if you're looking to save a) money, b) effort and/or c) headache.

Sell the GT, buy a GTT.

Sorry to rain on the parade.

It isn't just that though

Gearbox IS different (inside, had an auto guy literally laugh at the GT gearbox (after being built up by MV autos) whereas the GTT one he said "this is a muuuch better design and is quite nice"

Driveshaft, diff is different.

Bracing for everything is different. Have to ask why Nissan beefed it all up.

So you could do what I did, which is

a) replace GT engine with GTT engine

b) replace GT transmission with GTT transmission

c) replace GT brakes with GTST/356mm BBK

d) replace entire suspension setup

e) replace exhaust (the GTT one aint great but lol better than the GT surely)

f) replace fuel pump/entire fuel pump wiring (its terrible in GT)

g) replace diff

Its not just the engine, if you want to put a GTT engine into a GT, and want it to work just like a GTT, you will end up replacing every major component with GTT spec (or better).

Which means you end up replacing the entire car anyway.

If you're going to do that, there's a simple, easy way to swap it all at once, which is buy a GTT.

  • Like 3

It isn't just that though

Gearbox IS different (inside, had an auto guy literally laugh at the GT gearbox (after being built up by MV autos) whereas the GTT one he said "this is a muuuch better design and is quite nice"

Driveshaft, diff is different.

Bracing for everything is different. Have to ask why Nissan beefed it all up.

So you could do what I did, which is

a) replace GT engine with GTT engine

b) replace GT transmission with GTT transmission

c) replace GT brakes with GTST/356mm BBK

d) replace entire suspension setup

e) replace exhaust (the GTT one aint great but lol better than the GT surely)

f) replace fuel pump/entire fuel pump wiring (its terrible in GT)

g) replace diff

Its not just the engine, if you want to put a GTT engine into a GT, and want it to work just like a GTT, you will end up replacing every major component with GTT spec (or better).

Which means you end up replacing the entire car anyway.

If you're going to do that, there's a simple, easy way to swap it all at once, which is buy a GTT.

I have heard that the wiring is different, and you would need to rewire the GT interior into GTT ECU.

  • 6 years later...

Chids34,

Its not always worth buying a GTT instead of modifying a GT

if you want it build it, do it how you want.

i too have a GT which i have built into a GT/GTT/GTR what ever you want to call it, its a R34 skyline that i built to suit my wants and needs.

in many cases using a GT car as the start up build platform may be better for what you are building, as i too did not want to buy a GTT just to get a turbo engine then to have to eliminate many other parts and functions that makes it a GTT, example i didn't want like 4 wheel steering, traction control, etc. and if you come across a good deal, or a rare gt factory color like i did , dont pass on it hoping to find the same but in a GTT. well worth it to buy or stay with the GT and modify.

if you want to do that, do it.

there are situations where it is worth it to do it the way you originally described.

as far as this list:

a) replace GT engine with GTT engine/ would be a nice upgrade and way easier then putting turbo on a RB25DE

b) replace GT transmission with GTT transmission/ not a must as the stock GT trans are fine

c) replace GT brakes with GTST/356mm BBK/ not necessary for your application, yet, easy if want to do it upgrade brakes

d) replace entire suspension setup/ certainly not necessary get coil overs and add rear sway bar, then functionality same as GTT

e) replace exhaust (the GTT one aint great but lol better than the GT surely) /you probably going to mod the exhaust anyway

f) replace fuel pump/entire fuel pump wiring (its terrible in GT)/ this i would due not cause GT are terrible but because of the age

g) replace diff/ even if it was a GTT, these have vis diffs, which your gonna want to change to a mec. LSD and way, which are available for a GT rear diff

 

main recap build it how you want , and dont let any one tell you its not worth it, factor in what you want to spend on time and money. then do it the way you see fit.as long as you dont do anything illegal or try to sell it as something its not. who cares, build it the way you want. 

 

1 hour ago, GTSBoy said:

FFS! It was 6 years ago.

Took me nearly that amount of time to somewhat finish part of my build to get the power I wanted. 

 

 

 

 

 

 

Then I killed the motor in less than a year 😂

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