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-   -   Can I get some feedback on handling pre/post 2JZ? (https://www.rx7club.com/other-engine-conversions-non-v-8-118/can-i-get-some-feedback-handling-pre-post-2jz-949442/)

CKxx 04-08-11 06:33 PM

Can I get some feedback on handling pre/post 2JZ?
 
I'm in the process of buying an FD roller and I can't decide which motor/trans setup I want to put in it. I'd love to do a 2J, but I'm told it will destroy the cars handling ability (not that I would be able to tell, since I'm buying it as a roller..). I will be using the car as a street/track toy. I'd like it to still be somewhat competitive on a road course and not be a total boat.

I feel like the LS motor might be a better choice handling-wise, but the thought of owning anything LS powered makes some part of me die inside. Ha. I'm also not sure they will produce the type of power I am looking for. I've checked various "drag times" threads, and the I/H/Cam LS1 cars seem to put up pretty unimpressive numbers.

I'm sort of thinking out loud...

Any guidance is appreciated.

YoshiFD3S 04-08-11 07:43 PM

There are a few of us on here, myself and mk3brent, that are currently in the later stages of doing a 2JZ swap into our FD's.

Brent can probably give you a lot more scientific #'s and evidence, but I would challenge you to simply research the weight of an LS-motor and trans VS. a 2JZ motor/trans.

Keep in mind a couple things on the 2JZ though....for 1, you will end up going single-turbo, which in itself is lighter weight than the stock twins. 2, unless you have an extra ~$3k or so for the Getrag 6-speed transmission, you will be going with a lighter-weight R154 5-speed transmission.

Personally, I would venture so far as to ASSUME that a 2JZ would weigh less than an LS motor.

got_hp 04-08-11 09:29 PM


Originally Posted by YoshiFC3S (Post 10562398)
Personally, I would venture so far as to ASSUME that a 2JZ would weigh less than an LS motor.

i cannot comment on the difference in handling feel, but i did research the numbers, as ive been considering the same swap.

from what i can find:

2jz weight = 594lbs
1jz weight = 478lbs
r154 tranny = 120lbs

LS1 weight = 430lbs
t56 tranny = 125lbs

so a 2jz weighs about 164lbs more than the LS1, and the 1jz weighs about 48lbs more.

its not a huge difference.....but it's not just about the weight, it's about the distribution of that weight.

the LS1 is short and tucks its weight further back in the engine bay, keeping it as close to the center of the car as possible.

due to being an inline design, the 2jz/1jz spreads more of it's weight further forward towards the nose of the car.

so just by the distribution difference and the weight increase, i think it's pretty logical to assume that the LS1 will maintain better handling characteristics than a 1jz, and certainly better than a 2jz.

the question is......is the difference in handling actually enough for most drivers to even notice?


personally, i love the feeling of boost, and i dont track my car, so the reliability and high top end power of the 2jz is well worth the extra weight.
im still on the fence though, its a tough choice ;)

YoshiFD3S 04-08-11 09:59 PM

If I get the chance to weigh my FD and get an idea as to the change in the weight distribution, I'd be happy to relay that information to you and anyone else interested.

I think it's fair to say that with either motor, there would need to be changes made to the suspension to handle any driving function outside of street.

For me, my FD will be 99% street-driven, with occasional trips to a 1/4 mile track or possibly local parking lot auto-cross or drift events at MOST.....so for me, the weight distribution changes are really not significant to me on a personal level.

I'm willing to bet that 594lbs is with the stock TWIN-turbos and fully-loaded with A/C, P/S, etc...Although the 2JZ is a cast-iron block...at least it has an alluminum head..I'm willing to bet my single-turbo setup weighs less than that..

CKxx 04-09-11 08:31 AM

Very true. I do not intend to do it without a single conversion. I would also toss the AC and PS.

MK3Brent 04-09-11 05:16 PM


Originally Posted by got_hp (Post 10562591)
but it's not just about the weight, it's about the distribution of that weight.

the LS1 is short and tucks its weight further back in the engine bay, keeping it as close to the center of the car as possible.

due to being an inline design, the 2jz/1jz spreads more of it's weight further forward towards the nose of the car.

How do you figure?
The center of gravity between the two are the only difference, and it's not front to back... rather it's up to down.

13B-REW estimates are 379lbs. (Source)
Transmission 217 lbs.

So let's say 596lbs. (13B + transmission.)

Using the posted values for 2J + V160 (714lbs)
Using the posted values for LS1 + T56 (555lbs)
Difference of 118lbs.

Let's say a 20% increase in front end weight over 13B going to a 2JZ.

The LS1 sits about as forward in the bay as the 2JZ, the center of gravity with the 2J is about 1.5" higher than the V8.

got_hp 04-09-11 06:09 PM


Originally Posted by MK3Brent (Post 10563541)
the center of gravity with the 2J is about 1.5" higher than the V8.

i forgot about the height difference, since ideally you want the weight centered as low as possible.

first results i found said approx:

LS1
height ~20.5
length ~ 25

2jz
height ~23.5
length ~28.5

depending on how the engine mounts are setup, the ls1 has the potential to keep its weight further back and lower


dont get me wrong.....i still like the idea of a 2j or 1j better for a number of reasons.......but for handling purposes i think the ls1 has a slight advantage.

personally id choose 1jz, since id be happy with ~500hp reliable daily driver, and it keeps the weight down closer to the ls1.
if i was going for max power, id go 2jz.

CKxx 04-09-11 07:50 PM

I'm starting to consider a 1JZ+V160 w/a PT6272. My original plan was a 2JZ+V160 w/a PT6765 until people started telling me it would destroy the cars handling capability.

I'd consider an R154 as well, but the two I've driven felt like the shifter was a wooden stick getting dragged through a box of rocks. Are they all like this?

I'm coming from a 500+whp WRX and I'd like whatever I end up with to be faster than that was. That is why I was concerned when I starting seeing the trap speeds of the LS1 cars. My WRX was trapping ~125 in the 1/4 and most of the LS1 cars I saw where nowhere near that.

got_hp 04-09-11 10:30 PM


Originally Posted by CKxx (Post 10563700)
until people started telling me it would destroy the cars handling capability.

i highly doubt anything is "destroyed"...

have those people saying that actually driven a swapped fd?

MK3Brent 04-10-11 12:34 AM

I'll let you all know how it handles. Every aspect of my car has been engineered and designed for much worse conditions. I just cannot compare it to a rotary.

As for the r154, the shifter requires bushing upgrades then youre good to go.

CKxx 04-10-11 09:24 AM


Originally Posted by got_hp (Post 10563880)
i highly doubt anything is "destroyed"...

have those people saying that actually driven a swapped fd?

Haha. Of course not...

got_hp 04-10-11 10:48 AM


Originally Posted by MK3Brent (Post 10564018)
I'll let you all know how it handles. Every aspect of my car has been engineered and designed for much worse conditions. I just cannot compare it to a rotary.

As for the r154, the shifter requires bushing upgrades then youre good to go.

Brent, what part of NC are you in? I'd love to take a look at your build!

Cam_Ron 05-03-11 12:42 PM

From measurement of my friends 5.3L that was going into his fc, and the 1jz that is currently in my fc(same as 2j), they are almost identical in length from the crank pulley to the back of the block. Also, with the mounts that I made vs the hinson ones he bought, my motor is a bit further back than his.

MK3Brent 05-03-11 05:22 PM


Originally Posted by got_hp (Post 10564401)
Brent, what part of NC are you in? I'd love to take a look at your build!

It's in Greensboro.
I'll have you over when it's done! :D

CKxx 05-03-11 09:44 PM

What radiators have you guys been using?

YoshiFD3S 05-04-11 12:40 AM


Originally Posted by CKxx (Post 10603533)
What radiators have you guys been using?

My radiator is actually from an aftermarket radiator for a Chevy Camaro.

I forget what year, but according to my builder, the plumbing on it fits the motor perfectly.

CKxx 05-04-11 02:34 AM

If you could find out the specifics, that would be great. I had figured that a new inlet/outlet would have to be added, I was simply wondering which cores fit. If there is an option that is usable right out of the box, that would be awesome.


I'm going over a millions things in my head, still trying to decide which motor to use. I found a really nice (30k KM) JDM Supra RZ motor/trans/ecu, but I'm still concerned that it will handle terribly vs. a simple LS motor.

MK3Brent 05-04-11 07:08 AM

1 Attachment(s)

Originally Posted by CKxx (Post 10603533)
What radiators have you guys been using?

Mine is a custom built 2-row aluminum radiator built by Griffin.

Attachment 716558

CKxx 05-04-11 10:08 AM

I was trying to avoid excessive custom work if possible. I'm hoping to find a rad from another application that fits. So far, just from some browsing, it looks like this Mishimoto model designed for a 1995+ 240 w/SR motor may just work. http://www.mishimoto.com/nissan-240s...5-98-sr20.html The inlet and outlet are reasonable close to where I need them, and the core dimensions are a tiny bit less wide and about 1" taller than a standard mazda core.

Did you use -AN fittings for the coolant lines? I've always wanted to do that. My friend owns an Aeroquip distributor, but I don't they have anything large enough in aluminum. I was looking for something along the lines of a -24AN.

MK3Brent 05-04-11 10:18 AM

Yes, but they're -17AN.
No need for anything much larger. Just match up the inlet and outlet water necks.

As for the excessive custom comment, I can see where you're coming from.
There is much to be done for the swap though, don't be fooled.
It's a lot of work. I'm coming up to one year into my swap in 3 months. (August.)

You can slap stuff together, or you can do it right and spend the time and money. (I choose this route.)

CKxx 05-04-11 01:36 PM

Is there a specific element of the swap, or fabricated part, that you are referring to? Honestly, the wiring is the only part I was worried about, but I can't sort it out I'm going to pay one of my friends to do it, and a full Painless Wiring replacement of the chassis harness. Welding I/C and exhaust pipes shouldn't be any more difficult than any other car.

MK3Brent 05-04-11 02:37 PM


Originally Posted by CKxx (Post 10604576)
Is there a specific element of the swap, or fabricated part, that you are referring to? Honestly, the wiring is the only part I was worried about, but I can't sort it out I'm going to pay one of my friends to do it, and a full Painless Wiring replacement of the chassis harness. Welding I/C and exhaust pipes shouldn't be any more difficult than any other car.

You going to make your subframe, transmission brace, differential brace, transmission extension, and driveshaft?

CKxx 05-04-11 03:00 PM


Originally Posted by MK3Brent (Post 10604676)
You going to make your subframe, transmission brace, differential brace, transmission extension, and driveshaft?

Tech2 kit.

MK3Brent 05-04-11 03:26 PM

I'd be interested to see how long it takes to get their kit now, since their business burned down.

YoshiFD3S 05-04-11 06:12 PM


Originally Posted by MK3Brent (Post 10604755)
I'd be interested to see how long it takes to get their kit now, since their business burned down.

That sucks...but at the same time, it just makes 2JZ FD's like ours all that more rare.

And +1 on the comment of "taking your time". I'm at 1 1/2 years on mine right now. It's been a slow process, and although my engine bay isn't nicely polished and chrome like other swaps I've seen....my swap has still been done with the utmost attention to detail and I'm very proud of the quality work that's been done on it.


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