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-   -   1jz compaired to 2jz???? (https://www.rx7club.com/other-engine-conversions-non-v-8-118/1jz-compaired-2jz-808803/)

reaper60606@aol.com 12-24-08 10:48 AM

1jz compaired to 2jz????
 
hey im doing a super swap in my FD and finally decided to go with the toyota motors. i like the idea of haveing a v6 yet having a turbo aplication still. now i dont know exactly what to put in. im looking at either a 1jz or a 2jz. i am wanting to save some money so i was looking at the 1jz a little more. is there any major problems that occur with the 1jz besides normal wear and tear??? i just know that the 1jz has the 2.5 liter and the 2jz has the 3.0 liter....what else makes them different?? if anyone could throw me some info that would be very helpful. thanks.

red87tll 12-24-08 11:16 AM

1jz has the same bore as the 2jz just a shorter stroke. A lot of parts interchange between the two such as head gaskets and such. The 1jz revs a little higher but 2jz's make more torque. there are no major problems with either of them, both holding 7-800+ whp on stock bottom end. it is easier to find some items for the 2j such as bigger cams because the 1jz has problems with super big lift cams aka anything over 10.5mm. You will have no problem finding cams as big as 272's for the 1jz but if you want a ridiculous set of cams like 280+ the 2jz is the way to go. The heads are different... so its going to be 1jz or 2jz specific intake and exhaust manifolds.


You will need a bell housing for either one along with a trans. The 2j's came with the v160 6speed which are 3k+ for just the trans. The 1j's got the r154 found in MKIII supras and can be picked up for around $400.

cptpain 12-24-08 12:41 PM

to add to red87tll's post,

the 1JZ is a 2.5 TT vs the 2JZ's 3.0 TT thus the reason the 1JZ can rev higher.

parts do interchange, but only on the bottom end IIRC, the 1JZ head has problems flowing enough air to support higher than 700hp especially since the aftermarket was late to catch up on just before the 2JZ came.

for the head you can get away with mild cams, valves, and some port work, which is about it.

both engines require a "bump" in the center of the hood to clear the motor, as the ideal swap consists of mounts, and not a complete subframe modification, to keep the front suspension geometry.

as far as suspension, you'll need stiffer springs in the front, much more than staying with the REW as either motor is cast iron/aluminum head, which weighs about 30-40% more without accessories, manifolds, and turbos

red87tll 12-24-08 01:38 PM


Originally Posted by cptpain (Post 8823031)
parts do interchange, but only on the bottom end IIRC, the 1JZ head has problems flowing enough air to support higher than 700hp especially since the aftermarket was late to catch up on just before the 2JZ came.

Im not sure about that... there is a million threads on supraforums.com and supramania.com dealing with that. some think the 1jz heads are a better design hence the motive for the 1.5jz's (1jz head on a 2jz) but really, which came first the chicken or the egg. :)

and in reality are you planning on making more than 700 whp?

Miata_mx5 12-29-08 07:45 PM

The block casting is very similar. The 2j is a little taller. The 1j also has stouter/shorter OEM Rods. Both are pretty bombproof, although i prefer the 1jz-gte's higher revving nature.

You can do a 2jz-gte with 1jz heads (1.5JZ) or a 2jz-gte with 2jz-ge heads. The 2jz-ge heads are known to be a little higher flowing on top end.

*TOUCH* 01-10-09 06:17 PM

2j all the way...btw, in your original post you called the jz motors v6's, they are I6's, just in case you were confused.

jakkeduprx7 01-13-09 05:30 PM

what I was told if you have the money a 2jz is the ideal canidate for the swap but either motors are good for the swap....i'm tring to do the 2jz in my fc if you need more info try 2jzswap.com

ElysianD 01-23-09 05:50 PM

1jz = 2.5l 2jz = 3.0l :)


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