Is the KLZE Really Worth The Money

[posey92]

First off im back. I was on the forum bout 5yrs ago..any older members may remmber me talking about doing a rear mounted twin turbo setup on my mx3. I finally got my car back...well a different one but still my car. Great shape body wise. No big dents or dings...the passenger side of the lip was broken and missing but aside from that it has everything I want. 5speed v6 even a working sunroof. And I got it all with a clean title for $250 and a ps3:).

Enough introductions. My question is simply stated above. Is all the time effort and money spent tracking down a true KLZE worth it compared to the more readly available DE. I will be supercharging this with prolly between 5-8lbs using a Eaton M90 from the Super Bird I have lying around. This will be a long drwon out project. I will get a viable engine and rebuild it from the inside out. But to start I need to figure out am I searching for a ZE or DE.

[kulluminati777]

welcome back. I dont how it was back in the day but ZE´s are not hard to find anymore and are worth the effort BUT you stated your going with a Supercharger so I would go with the KLDE. Cheap, Better for Force induction (lower compression) and if you blow one up going to crazy another is right in the Pick and pull ready for you to put in.

[posey92]

I was hopin to hear that. Lol. I know a pic a part in cali that has half off days. 10 bux to get in a whole engine for lil over 100 bux..more to come eventually

[RX8SE3P]

The only notable difference between the engines when you actually find a TRUE ZE is KL31 cams, high compressions pistons and the ECU which has better a more aggressive timing map.

A lot of people here wank off to Eunos800/Millenia engines and call them ZE's. This is utter bulls---. They don't have high comp pistons, or KL31 cams or even a KL31 ECU. So why do people call them ZE engines, I have no clue lol.

That being said, the difference is not that large between a DE and ZE anyways. You'd be best off getting a DE and rebuilding that as parts are easiest to come by and the engines are readily available. The ZE is certainly not worth $600-1200.

If I were to do it all again, instead of paying like $1500 back in the day I would have:

Bought $200-400 DE
Colt cams
Ebay headers
Chipped ECU

= Faster than ZE for less

[kulluminati777]

I really noticed in other threads this whole DE´s being called ZE´s really gets under your skin. I bet you think about it day and night huh?

[Daninski]

Oh boy here we go, the old true ZE discussion. Bottom line is one has a straight and the other a curved neck. Both are ZE's with the straight neck 'usually' having the cams but both produce the same hp just at different rpm's. Reason, one was for a standard and one for an auto trans.
Anyway any DE you find probably has 200k plus where you may find a low mileage ZE that you can just drop in and drive. Good luck.

[bogaut]

you can find pretty low mileage klg4 though, since they are much newer than most DEs

[Jforce]

The only notable difference between the engines when you actually find a TRUE ZE is KL31 cams, high compressions pistons and the ECU which has better a more aggressive timing map.

A lot of people here wank off to Eunos800/Millenia engines and call them ZE's. This is utter bulls---. They don't have high comp pistons, or KL31 cams or even a KL31 ECU. So why do people call them ZE engines, I have no clue lol.

That being said, the difference is not that large between a DE and ZE anyways. You'd be best off getting a DE and rebuilding that as parts are easiest to come by and the engines are readily available. The ZE is certainly not worth $600-1200.

If I were to do it all again, instead of paying like $1500 back in the day I would have:

Bought $200-400 DE
Colt cams
Ebay headers
Chipped ECU

= Faster than ZE for less

What's a true ZE?

They new JDM engines will not have kl31 cams, they stopped producing the KL31 heads from engine block cast no 700.000 or so. Still has the High comp pistons and KL31 ECU.....

[MrMazda92]

The only notable difference between the engines when you actually find a TRUE ZE is KL31 cams, high compressions pistons and the ECU which has better a more aggressive timing map.

A lot of people here wank off to Eunos800/Millenia engines and call them ZE's. This is utter bulls---. They don't have high comp pistons, or KL31 cams or even a KL31 ECU.

You pretty much summed up what makes the "Real ZE" special in 3 letters.

Millenia KL + KL31/36 + EGR delete = 95% of the output of a "Real ZE" for half of the price. Less if you are near a Pick-N-Pull branded junk yard.

[RX8SE3P]

I really noticed in other threads this whole DE´s being called ZE´s really gets under your skin. I bet you think about it day and night huh?

Yes you got me there, that's all I think about.

Oh boy here we go, the old true ZE discussion. Bottom line is one has a straight and the other a curved neck. Both are ZE's with the straight neck 'usually' having the cams but both produce the same hp just at different rpm's. Reason, one was for a standard and one for an auto trans.
Anyway any DE you find probably has 200k plus where you may find a low mileage ZE that you can just drop in and drive. Good luck.

There is no way kl01 cams will make the same power as kl31 in two identical engines. That's like saying colt race cams make the same power, just higher in rpms.... it's wrong, there's less power down low and more up high. KL01 cams make more torque down low and make their power earlier but they don't make the same power as KL31 cams.

I acknowledge jdm curve necks are very close to 200hp but they are still the diet coke of klze. Most people have no idea how to identify a jdm curve neck from a domestic. No egr and a 7 nipple disty are usually a sure sign without checking pistons. Also, I've never seen a kl31 ecu in a curve neck car. Has anyone? Because kl31/36 both have incorrect vris for a curve neck.

Finally, I think the biggest hp gain for a single part difference between the engines are camshafts. Arguably you could say ECU (tuning).

I agree with you MrMazda92 - Get a junkyard Curve neck, chuck headers and exhaust on with a good chip or MegaSquirt and you'd hardly notice the difference. But if you do find colt cams or KL31 cams, chuck them in for even more power

Just to clarify, what I'm seeing are people buying domestic curve necks and saying yep, got a ZE here No 10:1 pistons, no KL31 cams, EGR hooked up, probably a DE or K8 ECU lol. That my friends is not a ZE

[Jforce]

Ok here's one:


KL31 ECU, 10:1 Pistons, KL01 Cams. < what's that?

It's JDM Imported for sure.

Also has the KL68 throttlebody, whereas the millenia/eunos has the KL47


Also i'm very sure that mazda cheaped out on some KL's for example the mismatch ports did come from factory. They also stopped using the KL31-1A1 heads after 97. The J-Spec Eunos was produced til 03. They have KLZE's.

From 97 no KLZE where therefore produced with KL31 cams anymore also NOT using KL31-1A1 heads.

[RX8SE3P]

Well in the example you just gave, it's not a full klze. kl01 heads and cams is a hybrid not a true klze.

When people think klze, they think 200hp. They don't think 170 to 190. How mamy probe and mx6 owners would be happy swapping in a kl01 cammed engine? They'd hardly notice the difference.

Of course if the only difference was camshafts it wouldn't be a massive difference but it would be noticeable.

[Josh]

From Interprep Tunings web site. All done on a US KLDE with mix-matching intakes and cams. I do agree with Blake on this. If I were to get a new engine I would build and mix match an engine setup. Knowing what I know know now I would go with a JY hybrid using KL01 heads and running the OBDII and MAF swap. A reliable 170-180 WHP according to others that are doing it..

1993 Mazda 2.5 ltr. V-6
Intake Manifold/ Cam testing, March 1996
No modifications to engine other than manifolds/cams.
Std. air filter/box
Std. cold air inlet to above radiator
Std. air flow sensor
Std. exhaust manifolds
Std. compression ratio
fabricated 1.75 O.D. exh. downpipes
fabricated 2.25 O.D. open exh. pipe, exiting to rear of car
VRIS functioning properly
AO6 computer


Dynamometer tuning results.
Peak torque Peak horsepower
1. 175.4 @ 4700 170.2 @ 6400
2. 173.5 @ 5000 180.8 @ 6000
3. 177.1 @ 4700 179.6 @ 6300
4. 173.3 @ 5000 184.9 @ 6900
5. 174.5 @ 5400 190.8 @ 6800
6. 170.9 @ 5700 203.7 @ 7200

Test Notes:
1. North American intake manifold/ North American cams
2. Japanese intake manifold/ North American cams
3. North American intake manifold/ Japanese cams
4. Japanese intake manifold/ Japanese cams
5. North American intake manifold/ Interprep 280/9.4 cams
6. Japanese intake manifold/ Interprep 280/9.4 cams

[Jforce]

Well in the example you just gave, it's not a full klze. kl01 heads and cams is a hybrid not a true klze.

When people think klze, they think 200hp. They don't think 170 to 190. How mamy probe and mx6 owners would be happy swapping in a kl01 cammed engine? They'd hardly notice the difference.

Of course if the only difference was camshafts it wouldn't be a massive difference but it would be noticeable.

True but a factory Hybrid.


I've always seen it this way:

JDM = KLZE

Euro/US = KLDE


And the example I gave dyno's 196bhp, so what difference will that 3 or 4 hp make?

If I were to get a new engine I would build and mix match an engine setup.

I believe that Mazda figured that out also, they kept the bottom end of the ZE and used the Kl-101 Heads, this way only 1 type of head had to be made.

Better springs + not having those any odd size hla's is a plus.

I think the JDM engines now imported will be more likely to have KL-101 heads than KL31-101 heads. Long neck manifold will get rarer.

But the question is: KLZE Y or N?


On topic: ZE is worth the money i paid ($1800 for engine, box, ecu, headers)

Going from 130 to 190 for that kind off money is great bang for your buck imo. (if your planning to stay N/A, if your rebuilding anyhow i guess it won't matter much DE or ZE going from other people's experiences)

[RX8SE3P]

Yeah at the end of the day for us 1.8L engines, any good condition 2.5L swap is going to be amazing

As for KLZE Yes No, I think the only true ZE was the straight/long neck engine from the MX6. But hey, get your KL01 cams re-ground from colt and if you have KL01 heads you will not drop valves. Then you'd make more power than a ZE.

Moral of the story - find a curve neck engine that is in good condition for as little money as possible. Buy headers and if you have KL01 heads, think about getting some higher lift cams put in there