da-man

I posted this over in the "newbie" section, 'cuz I am. But it doesn't look like that section gets much traffic. So I thought I'd bring it over here. Without the introduction.

the car: I have an old japanese classic that I've been trying to decide what to do with. I've narrowed it to 2 options: an LS1/T56 combo swap, or an AWD EVO swap. And so here I am.

My specific question immediately is this:
I see JDM half-cuts on Ebay regularly. less than 3K gets me an EVO III. $3500 gets me an EVO IV. (higher than that gets more expensive..... significanly more.) So what's the difference between the two?

I've done a little searching, but there's not a lot of info on the III. I see people posting about the IV here and there, and I know it was not available as a USM car. It seems though that parts are still available.

Here's my goals with it: I'm looking for no more than 500hp (the car won't weigh more than 2500lbs) and I can get the last 100hp of that with the bottle, if I have to. though I'd rather not. I want it to remain drivable, so my wife and I can cruise in it on the weekends.

help me out a bit, will ya?

TIA

Dan

da-man

no help here? Does anyone have an opinion on the subject?

Yogi_B

The difference between the two is that from the evo4+ they flipped the engine 180 degrees compared to the evo1-3s, so that may or may not be an issue for you.

The evo4 engine being slightly newer and having a twin scroll turbo and also being able to use bits off evo5-9s.

With the evo3 engine I believe you can use DSM bits.

karl3

with whats been said. about engine been other way etc.. they swop it around 180 degrees . so they could fit the ayc system in the newer chassis. no other reason.

i wouldnt of thought the engine was much stronger. as they both suffer from crankwalk. as for power yes e4 has 10bhp more standard. but the e3 is lighter.. lighter is better than 10bhp..

ecu,s both carnt be flashed as easy as e5 onwards.

they both use same injectors 510,s they up i to 560,s on e5 onwards

more or less share the same brakes. as e5 onwards as brembo,s

no matter whitch modle you get e3 / e4. its still going to cost the same or their abouts to get 500bhp. for starters your going to have to fully forge the car. including cam,s and bigger turbo.. then a good remap...


karl..

xspsi4

iTrader: (67)

evo 1-3 is lighter and cost less to make fast.

Yogi_B

AYC is the rear diff, the way the engine sits doesn't have anything to do with if it can have it or not.

And hes after a half cut for the engine and drivetrain so the fact that the evo1-3s are lighter isn't relevant here, just what is the better engine choice.

It would come down to what ever engine is easier to drop into the chassis I reckon.

da-man

That's what I'm talking about! Thanks for the input.
So if I'm getting this right:

Displacement didn't change. ONly the direction of the motor in the chassis.

Turbo changed, but if I'm to see 500hp, will I be changing the turbo on either one? or is that twin scroll unit on the e4 capable of doing that?

Neither are easily "flashed". So are there aftermarket ECM's available that I might look at using? OR is there a way around this?

Both have the same brakes, (and I'd assume suspension bits, or at least "layout") but the e4 has the AYC. Which is important, since the half cuts often come with the rear dif as well. Any comments on the AYC? With the amount of track time I've seen, and that this car is likely to see, I'm not so sure I really want it?

So if I could get some opinions on the above, that'd be awesome.

then: last but not least: Could anyone help me out with some rough measurements on the 2 cars?
Here's what I really need:
Track width. (hub to hub)
motor height (as compared to centerline of the hub)
Fore / aft measurement of the motor (also as compared to centerline of hub)

Almost anything else can be moved as I fabricate..... but those measurements are more or less "fixed". (Though I'll probably have to narrow the track a couple inches.... I'm betting I can find those couple inches somewhere.)

thanks for all your help. I'll post-up pictures as I go. I've been building a rotisserie to put the body on to do the bodywork, and it should be on it by the middle of next week (I ran out of steel last night)

Dan

Yogi_B

Correct.
The evo4 turbo is the same as the evo5-8s except for a smaller exhaust housing so yes the turbo will need to be changed to something bigger (on both engines), just look at what people are doing here to see what sort of parts you need to reach 500hp as the evo4 engine is pretty much the same as the later ones just with weaker internals. For the evo3 engine just look at what the DSM guys do to get 500hp.

You can either drop in an evo7 ecu and reflash that or use any aftermarket ecus such as autronic, motec, gems.

Keep in mind that AYC does have its weak points, and if you are in a location that has no one that knows about the AYC diff then you could be screwed as it requires bleeding and someone who knows how to do it. All the RS evos which are used in competition don't use the AYC diff and use a regular LSD which is far stronger, stick with the LSD which all the US evos come with.

da-man

Yeah, as I read-up on the AYC, I'm really unconvinced. It reminds me of how I felt when Honda and BMW started putting ABS on their motorcycles. I really want to be able to control that myself. Granted, with the rear dif, there's not alot to control, from the drivers' perspective.... but I'd rather not be trying to second-guess a computer with it.
So the question: Can I simply disable the AYC if I use the JDM rear dif that comes with the e4 half-cut? Or does that leave me with an 'open' dif?

thanks for all your help.

measurements would still be extremely helfpul at this point.

Yogi_B

You can pull the fuse for the AYC computer but it leaves you with an open diff. But the problem with AYC diff is that the casing twists under sever stress and tends to cause the pinon(I think) to not stay in place which results in gear teeth breaking and the casing splitting open.

Heres something that may help a tad with the dimensions:
http://img230.imageshack.us/img230/16/evo4dimenpu8.png