yeah i'm not 100% sure, but i think the T618Z housing and exhaust wheel is larger than the T517Z...so the housings wouldn't be interchangeable.

 

Do you mean you can't fit a 18G wheel in a T51 housing?
Greddy doesn't release much information on their modified mitsubishi turbo, but the 18G is roughly a 50.5mm compressor wheel. The T518Z 18G has this wheel in the turbo.

I will post some more information to explain this tomorrow when I have time

 

see that confuses me because i know in a mitsubishi turbo... you can just take it to Bushur racing or other places and have them up grade it to a 20g. I thought you wouldnt have to change anything out of it like the exhaust housing and what not.

Because if thats the case.......we shoudl just be able to have them up grade with no problems of anything bolting up.

 

S2kandy, it can be confusing and frustrating. I ordered a pair of T618Z because it's the largest low mount I can get for my gtr and dont know exactly what turbine wheel I am getting and also what result I will get. However I am in uncharted territory with my engine+ turbo setup. IMHO don't waste your money on modifying a good turbo. The T518Z is a very good (if not the best for it's size, durability and response) and popular turbo. If it's not suitable for your need then you can easily upgrade to the next one. I am sure you can get good money for the T518Z. I will let you guys know if the T618Z will replace my T517Z....you can never be certain with these things

I am not an expert with turbo. Unlike the Garrett there is not much information on the Greddy turbo either. My understanding is that the 51 or 61 refers to the compressor housing. The 18G to 25G refers to the compressor wheel. T518z, T618z and T67 are hybrid turbo from the mitubishi TD range. The T517/T518/T618Z are smaller hybrid turbo compare to the larger standard size T67/T78/ T88 hybrids. I have a T67 on my s2k and I know that it is a combination of TD07 compressor housing and TD06 turbine housing in 20G compressor wheel. You can get a 25G compressor wheel.

There is not much information from Greddy on their small hybrid TZ series. Greddy may provide more information to their dealer...may be Chris will be able to get some more information from Greddy. Could someone confirm that the turbo in this kit is a T518z 10cm2 18G?

My guess is that the T518Z 18G is a hybrid of TD05 compressor and possibly a TD04 exhaust turbine with internal gate. Greddy doesnt list their specifications but working on the mitsubishi spec; the wheels are roughly 50.5cm compressor and 45mm turbine wheel. Please don't bank on this as this is only my an unconfirm speculation. I will be happy if someone can confirm or deny this information. It would be good for the owner to know exactly what is in their turbo but I doubt that Greddy will leak too much secret info on this. Just rest assure that you have one of the best turbo IMHO

 

well having an 18G as the best turbo as you so put it, would soley be on the person using it i believe.

When i was in DSM's and had my eclipses. I went from the puny T25 to 14B, small 16G, EvoIII16G, to the Precision 50 trim t3/t4 Turbo.

Now depending ALSO what size engine you have makes that differentiate in opinion as well. For example. Pushing a 50 Trim on a 2.0 versus pushing a 50 Trim on a 2.2. You better believe the 2.2 is gonna spool that much quicker than the 2.0 because of that added displacement.

In my opinion, i think the 18G IS a great daily driving turbo. Low end grunt, not much lag, pretty good top end but feels like its running out of breath. Greddy Obviously made this kit for safety issues on the engine and yourself than the flat out HP of it.

We also forget is that this turbo set up is going on a HIGH compression engine... 10PSI doesnt sound like much but when your already running high compression, it doesnt take much more to make a 2800 LBS car go faster. Personally, just from my experience, i'm very skeptical on putting the kit on a stock HG. I know they all say its safe, but at the same time, i would rather just go the extra mile in putting the 3mm HG on.. That way, you can ultimately run higher boost and have even MORE HP.

Thats where i wanted the 20G and obviously it seems like its not gonna work because of the flanges and what not. So what do you do? Go buy another manifold and turbo and reweld the downpipe to fit.

If i keep this car, i Plan on putting the head gasket in the time of the install, adding the 650cc's, and retune it. Until then.. money is building in the bank to purchase a turbo'd car. like an evo or STI. SO much easier to build hp.

 

Don't jump to the conclusion so soon buddy. I am hoping that the T618Z is a direct replacement. My guess is that it has a compressor similar to TD06 and same exhaust housing as the t518z with a different turbine wheel. It may even be a 20g instead of 18G. Anyway I will let you know when I get my 2 turbo. I will have to open them apart for heat coating so I will try to find out what wheels are in them

 

Good man! It just seems so logical that it would be able to fit you know? I never had them ofcourse so cant say first hand yay or nay. but that would def be awesome if you could check it out and see.

I guess JUUUUST incase, the WORST case scenario would be the mani/turbo swap out. But hell. a 20g is nothing to skauf at. Its a decent turbo.

 

Just a little update as promised.

I've received the T618Z 10cm2. I am working interstate so I got my mate to test fit the turbo. They replace the existing T517Z 10cm2 turbo in my skyline and fit almost perfectly. My mate said everything bolt up and the dump pipe flange is about 1.5mm smaller than the exhaust turbine. My mate also disassemble the turbo and sent them off for heat coating. Since I am away I won't be able to send the turbo off for measurement as promise earlier..sorry. I am also unable to source an extension pipe (there are 2 parts in my RB dump pipe) with exactly the same flange to fit the turbine housing, so I will bolt the new turbo with my existing dump pipes. I will keep you guys inform of the power gain in the next few weeks and if the turbo gasket get blown.

So if the T518Z in the f20c kit is the same turbo as the T518Z or T517Z used in the RB26 kit, the T618Z will bolt in. You may need to modify the flange on the dump pipe to get a perfect fit.

Has anyone experince any gasket problem with the dump pipe flange a tad (1.5mm) smaller than the exhaust turbine housing?

 

I thought you were going Rotrex.

Anyways, if you lower the CR, are you planning on using an AEM for engine management with the greddy, or will the ULT work?

 

So it sounds like the turbos are T28 flanged.

Only problem with gasket mismatch is that it messes up the flow. Can you grind it to the right size?