Jump to content
SAU Community

Recommended Posts

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.

Link to comment
https://www.sau.com.au/forums/topic/447114-r34-gt-to-gtt-engine-swap/
Share on other sites

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 😂

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
×
×
  • Create New...