Difference between 2jzge and 2jzgtte buttom ends
 

so i have heard rumors that the IS300 2jzge has the same exact buttom end as the 2jzgtte .. is this true?

can you just get a top end from a 2jzgtte and slap it on a 2jzge and make it into a complete 2jzgtte?

No. The 2jz-gte bottom end has different (compression) pistons and oil squirters.

Yes, except for the pistons and oil squirters.

This is not entirely true. You were right in saying that the bottom end is different in the compression and oil squirters. The compression of the 2jzge motor can be taken down to gte compression with a thicker head gasket. Therefore the only difference is really the oil squirters.

Also a TT head CANNOT just be slapped on a non turbo block.
http://www.supraforums.com/forum/sho...d.php?t=225971

I remember reading in turbo mag this. Here is the article. I hope this helps out.

http://www.turbomagazine.com/features/0312tur_is300/

Hope the link works

Yes, BUT if you lower compression with a thicker headgasket, the shape of the resulting combustion chamber would be different than using an oem headgasket and 2jz-gte pistons! This means a 2jz-ge with a thicker headgasket won't make power as effectively as a 2jz-gte (or even a 2jz-ge shortblock with 2jz-gte pistons).

Again, the pistons are *different* (not just a different compression ratio). For example, the 2jz-gte pistons have a channel to distribute the oil from the oil squirters. Although Toyota has been less than completely forthcoming on the details of the piston differences, most emperical results suggest that either the exact alloy of the piston, or the structure of the piston itself results in the 2jz-gte piston also being stronger than it's 2jz-ge counterpart.

Actually, the thread at this link details HOW to "slap" a TT head onto a non-turbo block, AND a complete list of everything you have to purchase. In fact, most of the items listed in that thread are normally included with a 100%-completely-assembled 2jz-gte head.

In other words (to get back to Dboz's question), yes you can put a 100% complete 2jz-gte head onto a 2jz-ge shortblock...and end up with a fully-functional 2jz-gte 'longblock' (again, other than the oil squirters AND the pistons). To get the 2jz-gte turbochargers (or a single turbo) 100% functional on that 2jz-gte 'longblock', there will be other work required too (eg. installation of the pressure cannister, runing oil line(s), and installing a 2jz-gte water pump). To get the whole package functional in your IS300 engine bay, even more is required, like (for example) a 2jz-gte power steering reservoir). The supraforums thread that shorty_du_op posted (thanks!) contains some very good informtion on the overall process.

Skil, thanks for posting this link.

I agree that a 2jz-gte typically isn't a drop-in solution for a 2jzge-equipped Lexus...for example, there's no reason why an engine bay designed for a 2jz-ge should already have room for 2jz-gte's turbos.

...BUT (again, for example) the oil pans in that article didn't need to be "custom" for the sake of the 2jz-gte shortblock ... to make a complete 2jz-gte fit in the IS300 engine bay (again other than the turbo(s)) they only needed to use IS300 oil pans bolted to the 2jz-gte...and they do bolt directly on.

Also, I'd be willing to bet that they could have used the oem motor mounts IF they didn't have to worry about turbo and/or transmission clearances. In other words, it wasn't any 2jz-ge<->2jz-gte shortblock differences that necessitated the modified engine mounts. These custom motor mounts they chose to use (for other reasons) are what necessitated the custom oil pan.

You are exactly and completly correct. And you are welcome. I was worried that the link wouldnt work.

I would guess that they could have made the mounts work but I think the engine craddle on the alteeza is a little different than a typical supra isnt it? I could be wrong. Also you are right about the oil pans. And they couldve used the stock one and just put a bung on it for the oil line.

And your other post was exactly correct too. They do use different pistons not only are the squirters different but they are a different compression. Also if you take a piston off of a IS300 and compare one to a supra piston you will see differences in its structure. Rendering the 2 motors technically not being the same but a totally different motor because the design of its parts are different.

Thanks for your insight on this. O and btw, do you know if the is300 and the supra engine craddles are the same? I have always wandered this.

I know the cradles are different, and as a result the oil pans are different. That said, I'm not an IS300 expert...I'd guess the motor mounts are different too - but even if that is the case, the IS300's motor mounts will bolt to the 2jz-gte block just fine.