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Chances are if you have a curved neck ZE you won't get the cams. Straight neck Ze's have KL-31 cams curved neck ZE's may not. Only way to tell is to pop off the valve cover and check or buy a straight neck and install a curved neck manifold.

I bought the straight neck with kl31 cams and swapped in a millenia curved neck manifold

But, i would like to set the vris point as optimal as possible.


How do you dyno tune something like this? Just trial and error?

To get the proper vris points, you would need to do 4 dyno runs.

One with both VRIS closed
One with both VRIS open
One with VRIS 1 open
One with VRIS 2 open.

You need to manually keep them closed/open.. and also disconnect and plug the vac lines running to the actuators.

Overlay the torque curves so that you can see where they intersect, and those will be the optimal vris points.

I did this with my setup after extensive intake porting and many mods, which made the VRIS points much different versus the stock points.

very nice information.

So, to make sure I understand this right, I could use an MX-3 tb with a Curve Neck/Millenia IM? The IAC and such are all the same, only the MX-3 uses a 55mm tb and the curve neck comes with a 60mm one?

right

Here's something to possiably blow yall's minds I just got my ze yesterday curved kneck .YAAAAAA!!! FINALLY!! also ordered a transmission for more top end but somehow they forgot to send that after waiting almost 3 months to get the motor and trans. here and the front head code reads as kl31 1A1 and the back is kl31 101 it seems as I've gotten one with two differant cams am I right? I didn't notice this untill lastnight after looking it over really well but the linkage connecting the trottle cable to the butterfly linkage was bent really bad the small roller bearing that looks as if it goes in the slot is bent down and out of the butterfly linkage I made an attempt to bend it back but it's not opening the throttle compleatly or closeing it compleatly either is there any way I can remove this to repair it? Or I just need to call Noyan back and have them send me another?? I'm getting really sick of dealing with these jack offs seems they can't get anything right. Also the main wiring harness was cut when they removed it I called them and he told me that it wouldn't work anyway being that was from a jap. car due to the diff. seating positions..

do the intake resonating tubes swap between the manifolds? Like from the de ze or k8 to the millenia intake i can only find a millenia intake without tube connecting the runners..

What's better? Millenia IM with a KL31/36 or K8 IM with K8 ECU?

how bad is it for the car that the VRIS points will be off?

greenstorm wrote:What's better? Millenia IM with a KL31/36 or K8 IM with K8 ECU?

how bad is it for the car that the VRIS points will be off?

You're question really doesn't make much sence, you need to be more specific...

- The K8 ECU is spot on to have the VRIS points for it's own K8 IM of course
- The KL31/26 ECU is designed for the straight neck IM, so the VRIS will be off for the Millenia/Curved Neck
- K8 IM is very restrictive on a KL
- K8 ECU and a K8 VAF is a very inefficient combo for a KL, you can get away with running a KL02 VAF, but it's still not ideal. (OBDII exempted)
- All the VRIS points do is change the path of the air for the best powerband, it's not bad for the motor in anyway, some people even disable them

We have to use a curved neck manifold because of the battery and brake booster interference. You can use a KL intake, but the ports on the heads will not match the ports on the intake, so more restrictive, less HP.

KLZEs have square ports on the heads. Most KLZEs have straight neck manifolds it seems, so your only alternative for port matching would be a millenia intake manifold because it also has square runners and is curved so it will fit in or bay without hitting the battery/brake booster.

So this was mentioned up higher in the thread but was unclear to me. I found a 95 Millenia IM at a junkyard (SC, US) with square ports, Now, in order for me to get it to work(not just bolt on) I need to also get the TB, and fuel rails right? or do I need to grab the injectors as well?

I guess what I am asking is if I get a straight neck KLZE, and a Millenia IM will the parts match up to the KLZE? (i.e. KLZE fuel rails and injectors going onto the Millenia IM, throttle body from KLZE fit on the millenia IM, etc) What do I need to make sure that I also get from the JunkYard?

Another question I have is if I get a curved neck KLZE, what is the biggest downfall? I know there is a difference in cams but from what I have read I have not found a designation of a curved neck ZE hp being less like:

*******example
KLZE Straight neck: 199hp
KLZE curved neck: 160hp
example*********

To denote that the "other" cams are not as good.

I hope this isn't confusing and I'm sorry if it is.

Patrick

Fuel rails is equal and injectors too.

You indeed need to Throttle body because the IAC wouldn't fit.

Besides the KL31 cams the longneck also has higher compression pistons (10.1 vs 9.2:1)
This makes a curved neck more suitable for boost but also provides about 10hp less.

This thread reminds me alot of the earlier 90-post thread about DE vs ZE engines and the potential gains. I just finished a "DE" swap into my 92 GS. The following isn't a worklog, but it is a compilation of experience and observation:

My "DE" is actually a 95 Millenia engine.

Heads: It has the same square-port KL31 heads as a ZE. This engine also has 9.2/1 compression ratio as opposed to the 10.0/1 of the KLZE. I refer to it as a semi-ZE.

Manifold: square port curved neck manifold.
Note: I found a number of later Millenias and 626s with square port manifolds and true DE oval port heads. Why Mazda would purposely mismatch the ports is anyone's guess, unless it doesn't really matter much on a mild engine. My assumption is that the square-port heads flow better, especially at high RPM. I put a cone air filter (Not CAI) on because of space limitations and the ignition components below. Yes, the K8 throttle body would work, but why? The Millenia TB is 60mm and requires only a bit of ingenuity to use the stock throttle cable.

Cams: Stock KL01 cams.
Note: The KL01 cams have slightly less lift, slightly less duration, and MUCH less overlap and valve acceleration than the KL31 (ZE) cams. It was noted in a previous post that KL01s and KL31s have the same intake and exhaust profiles. This is misleading; it means that both intake and exhaust on the same cam have the same profiles. There is a major difference in profile between the 01 and the 31 cams. The differences would account for the peak horsepower of the ZE coming at higher engine speeds, with less bottom-end torque.

Exhaust: XS-Power stainless MX-6 headers, 2.5" freeflow cat (no matrix that I can see, just straight thru!), 2.25 tubing, a 24" bullet resonator, and a straight through Magnaflow muffler. This setup is great, but too loud at heavy throttle. The muffler will be replaced with a quieter one soon.

Ignition: GM HEI conversion with Blaster 2 coil. I gutted the coil and ignitor out of the stock K8 distributor and installed a power tower. I tried using the Millenia crank sensor and had huge issues until I replaced it with a K8/626 sensor. Apparently the Milly sensor resistance is different enough to screw with the ECU.

Tuning and other parts: I am using a KL01 VAF from a DE MX-6, and a chipped KL07 ECU (V6 Probe) with a Stoker100 custom chip. The chip was created to use US 87 octane gas and to lean out the mixture for more top-end power. Stoker also used modified VRIS points which are prob stock for the JDM or Australian Eunos.

Observations: This combination runs very well and pulls HARD through the redline to the 7500 rpm fuel cutoff. That said, objectively, the max power is at 6000-6500, which is in line with the Milly powerband, considering the freeflow exhaust. All Millenia engines, round and square port were rated at 170 hp. I have to assume that the 95 engine was stifled by exhaust and ATX tuning, and that the headers, open exhaust, and chip opened up the top end.

There is a great deal of information and disinformation about DE and ZE engines floating around. My semi-ZE is factory rated a few HP higher than a DE, but less than a ZE. I can only assume that the wilder cams, higher compression ratio, and more aggressive tuning to allow for a 96 octane fuel requirement would easily make a 30 HP difference. I also feel that the headers and chip get some or most of that back.

There's also a great deal of talk about the curved/straight neck manifolds. I would freely admit that the straight neck manifold is more efficient at very high RPM. However, I feel that the lower RPM torque of the slightly milder engine is more usable on the street. My engine will pull from 1500 RPM, hard from 2500. It makes every day street driving, including stop and go, much more enjoyable than the K8 ever was. AND it'll smoke the tires all the way thru first, pull hard everywhere else when I want it. It's a street rocket!

One final word, really. There is no doubt this was a performance conversion, but the car is my daily driver and has to be usable in all situations, from stop and go to autocross. Absolutely MAX performance is less important that usability. I got both, with a huge increase in performance.

Thanks for reading; this was far more than my 2-cents worth. Comments?

This thread is about intake manifold differences, not about the differences between a ZE and DE. There was JUST a thread on that exact discussion, and it got closed. This thread isn't the place for another one of these discussions.

And one last note, have fun revving beyond 7000, especially to the fuel cutoff. Your engine will go a while, but don't expect 100'000kms out of it with that kind of driving. Especially with KL01 cams, there's absolutely no point to rev that high. The people I know who drove their car like that replaced many motors and complained that they were s---. Hmm, I wonder why...

Post reported to recommended to be moved to perserve the quality of this thread.