2jz twins on 1jzgte

[Albert]

Hey guys

Ive tried searching with no luck. Im trying to see if anyone has put 2jz twin onto their 1jzgte. I know it is possible. and Im pretty sure I know how to. Just seeing if anyone has pics or details about the modifications that need to be done.

From what I gathered, you have to modify the 1jz manifold to accept the 2jz twins.
you run the 2jz cold charge piping and inlets.

What Im confused about is a guy that did this on Supramania said he had to make a spacer for the 2jz y-pipe section. Not quite sure what he ment? a space between the turbo to downpipe?

I have like 8 Ct12a and 4 Ct20s laying around, Just dont have a motor to mock up to do the testing myself.

If anyone has info or pictures to clear this up please let me know.



For clarification this is what ill be doing to a customers car:

Take a pair of JDM CT20 2jzgte twins,
#1:Replace the ceramic turbine blade with a higher flowing steel/inconel turbine
#2: Machining the Compressor housing to fit a GT2860 disco potato compressor wheel
#3: Machine open the wasgate ports to a 34mm
#4 Machine a sleeve for the rear turbo, and convert it to internally gated control
#5: Get rid of all the B/S sequential in the exhaust and charge piping
#6: Run in full true parallel

Just nee a custom Downpipe and spacer/modify what ever need to be modified.

similar to this:

 

[hvyman]

I know someone who did it. Pretty sure all you have to do is drill a couple holes bigger. And bang the firewall. Sorry don't have anymore.

 

[MightyAl]

Excuse me if this doesn't make sense but I am relying on old old second hand memories. I know a guy that did this and he used 2 front ct20's in order to not have to use the bypass as the rear ct20 does not have wastegate. In order to get the ct20 to line up with the 1j manifold he had to offset it from where the downpipe connected. It was easier to machine a spacer then it was to modify the exhaust manifold. It has been awhile but I think that is the reasoning behind the setup.

 

[Albert]

I know someone who did it. Pretty sure all you have to do is drill a couple holes bigger. And bang the firewall. Sorry don't have anymore.

It will be going into a Sc300. So I doubt he will have to bang in the firewall.

 

[Albert]

Excuse me if this doesn't make sense but I am relying on old old second hand memories. I know a guy that did this and he used 2 front ct20's in order to not have to use the bypass as the rear ct20 does not have wastegate. In order to get the ct20 to line up with the 1j manifold he had to offset it from where the downpipe connected. It was easier to machine a spacer then it was to modify the exhaust manifold. It has been awhile but I think that is the reasoning behind the setup.

Hmmm. well im using the rear and converting it to have a wastegate.

 

[MightyAl]

Hmmm. well im using the rear and converting it to have a wastegate.

I think the front is interchangeable with the rear. I could be wrong but it could save you the headache of converting a rear to having a wastegate.

 

[Albert]

Its not a headache. and Id rather do it this way so people he isnt trying to source 2 fronts.

 

[MightyAl]

Its not a headache. and Id rather do it this way so people he isnt trying to source 2 fronts.

I am not going to argue since you clearly have the skills to make it happen. Eliminating the sequential operation will certainly ensure a longer life for turbo #2.

 

[destrux]

Looks like a cool project. The 1JZ manifolds seem like a restriction though, they are pretty small inside. Planning on porting them or do you think they'll be ok?

 

[Albert]

If you compare the 1jz vs the 2jz, the 1jz mani is a lot smaller, they will be opened up

 

[Gt40881j]

yeah i buddy of mine was the guy on SF that mounted ct20's on the 1j. he had to space the turbos 3/8" apart so that the manifold ports matched up, then had to modify two of the 6 mounting holes on the 1j manifolds so that they would line up. issue was that the much larger ceramic blades werent as strong as the tiny ones on the 1j. so anything over 14-15psi and they would(and did grenade) time and time again. but i hear your solving that problem...

 

[soapra]

I have done this and have a setup running for over 3 years at 16 psi with no issues. Turbos are still good.

 

[Albert]

These will be getting steel/inconel shafts, so I don't think there will be an issue