1.5 jz an extra 500cc?

NO


1.5jz is a 2.5 1jz with a 2jz bottom end making the 1jz a 3.0

 

Why what combination would have made 3500cc's??

 

I thought the swap was done as the 1jz head was supposed to flow better than the 2jz.

 

Bullshit myth, it doesnt

 

Does rev better though, Andy Grey from PV has one in his Mk2 drift car.

 

1JZ head doesn't flow better, but the smaller ports cause the air to flow faster, thus helping the turbo spool quickly.

 

a test was done on one of the supra forums with flow rates. a 1j head with 2j valves does flow better than a 2j head.

 

yeah looked into that also was bench tested by a company in the us, il try and find a link for it somewhere.

 

That was the first time Iv laughed all day.. Cheers Dan

 

I thought it was a bullshit myth myself to be honest. I would be really interested to see that data/link to the supra forums thread. Guess it would be interesting reading.

 

main reason for doing it is, that the 1jz heads are cheaper to source than the 2jz heads

 

here is the proof that out of the 1jz and 2jz head, the 2jz is better

The truth about the 1JZ vs. 2JZ cylinder head - Supraforums.com

there is a tread somewhere that i cant find but basicly it involves using the 2jz valves in the 1jz head and it flowed more than the 2jz head,il keep looking and post when i can find it

hope that helps

 

I'd have said that the main reason for doing it is that you already have a 1JZ manifold and turbo, and either have a broken bottom end, or want more capacity/torque/power. Otherwise, you might as well use the 2JZ-GTE head.

BTW, IIRC, there's an oilway which doesn't quite match when you put a 1JZ head on a 2JZ block.

 

Any of the highly modified Toyota cars Ive imported all have had the 1.5JZ set up. My daily driver is a 1.5JZ Chaser with a T88 34D & it spools up really quick. The Japs know their stuff so I reckon the combination is a good one.