In-depth discussion on KF-ZE

[lakersfan1]

So, far the Forum seems to just have speckles of information on the KF-ZE swap. Usually Probetalk has better FAQ's but they don't even want to discuss the KF-ZE on there because it'd be a little of a downgrade for a Probe owner. But it'd definitely be an upgrade for everyone here, if not a viable replacement for high-milage K8's. And the KF-ZE can usually be had for half of a KL-ZE. If we're going to get an FAQ on KF-ZE's going, it's going to be on MX-3.com since we're the only ones with motivation.

So I'm asking everyone who's successfully completed a swap to list as much info necessary on the swap as possible.

Some questions I myself have are as follows:

1. Is there a definite seat-of-the pants difference in the KF vs the K8 with no other modifications.

2. What VAF is needed to run properly? The one on the K8, or do we need the one from a KLDE?

3. What is the stock KF intake manifold more like? Is it like a K8 (little with round runners) or is it like a KL-DE (medium sized with round runners) or is like a Millenium/KL-ZE intake (with big square runners). This will not only tell us which intakes are better swapped in, but also which phenolic spacers to buy - the KL-ZE or KL-DE/K8 style. Also, does it only come stock with a straight neck? If so, we'd just need to move the brake resivoir to get it to fit, right? Anybody know what needs to be done to move the brake resoivoir if we want to keep the KF-ZE intake manifold?

4. What size is the throttle body that comes with the KF-ZE intake? Is it bigger than the K8 throtle body? Is a KL-DE throttle body bigger?

5. What needs to be done to get the EGR hooked up? Do you just need to remove a plate? Do you need to drill your own hole to thread something in? I have no idea about EGR since I've never had to screw with one, but most of us need to pass emmissions.

6. Are there any other parts that need to be picked up that you can't take off the K8 and run effectively?

7. Lazzyie can get the KF15 ECU for you, right? And that is the only ECU to use for stick shift with the KF-ZE, right? What's the going rate shipped for it from Lazzyie in U.S. funds?

[TsiMiata]

Originally posted by lakersfan1:
3. What is the stock KF intake manifold more like? Is it like a K8 (little with round runners) or is it like a KL-DE (medium sized with round runners) or is like a Millenium/KL-ZE intake (with big square runners). This will not only tell us which intakes are better swapped in, but also which phenolic spacers to buy - the KL-ZE or KL-DE/K8 style.

Outlaw lists the spacers as the same for the KLDE,KFZE & K8

[UrBaNsTyLe55]

well although i don't have an mx-3 i have a 91 protege which is the samething with a kf-ze swap, answers go as followed, for one the manifold that you can swap on to it is the kl-de since it uses the same runners as the kf-ze, throttle body size of the kf-ze is 55mm, so if anything swap also the kl-de tb if you buy the manifold, ecu and vaf goes as i'm using right now the kl-de ecu and vaf and car runs great i have a nasty pull at 2500 to redline almost like my very own vtec, i have talked to others who said that with the k8 ecu u get a pull at 2500rpm and then again at 5000rpm, i don't know personaly because i haven't tried it yet.as for difference between the k8 and kf that i don't know since i never had a k8 but its a huge difference compared to my bp now as for the egr that i decided not to use so i got a check engine light because of it, distributor and other stuff can be swapped from either the k8 or kl-de no difference, the only thing i must add is the kf-ze has nice!!!!!!!!!!!!! top end horsepower but lacks low end, nothin a UDP or turbo can't do. other info for me to add is for one the kf-ze cams are the most aggressive out of the k-series motor so alot of you kl drivers would get a nice hp increas by slapping them on, from what i have been told you can easily use k8 headgaskets if interested on doing an engine rebuild. manifold wise it only comes with the str8 neck. but one thing you must look for when making shure you have a kf-ze is that right under the power steering pump theres a small square with the letters kf on it many think they have a kf-ze and really they sumtimes have a k8 since both motors use the same heads, as for turbo wise i have been told stock internals can handle the max of 7psi, when i'm done with my turbo setup i'll post some faq's on it and more step by step things to be down, i also know that mnemonic has a series kf-ze being build and knows alot about the kf-ze as i do, well thats my two sense

[lakersfan1]

Two more questions:

1. How do you distinguish a KF-DE from Europe from a KF-ZE from Japan?

2. I know you need to use the distributer from the K8. But is the KF-ZE distributor useful to sell for any U.S. Spec cars? Like can people with OBD1 or OBD2 KL-DE use this kind of distributor? Just seeing if any money can be made off selling the used distributer, or if it might as well be thrown in the garbage?

[Custommx3]

I agree. I have the KFZE and have yet to put it in. I was told you cannot use the k8 headgaskets.
My heads are k8101, J NumoniK are k82.

Brian (J NumoniK) said that he compared the two gaskets and they indeed were different.

The KF comes stock w/ a Je50 VAF. Some people use a KL ECU, I myself and Brian have the KF 15 ECU. I plan on installing mine soon. I recently got another MX-3 since my buddy decided to total out my project car during his KLZE swap. So MAYBE I'll get to put it in this car....

[lakersfan1]

Barry, how much was the KF15 ECU, and which is the JE50? Is that the one we already have on the K8 or no?

<small>[ March 22, 2004, 03:21 PM: Message edited by: lakersfan1 ]</small>

[mx3man83]

Good luck trying to move the brake booster. I don't believe it has or can be done. I just modifed my klze throttle body and tilted the engine slightly forward to make the straight neck IM fit. If the IM on the kf an klze are similar then maybe what I have done would be helpful to you KF guys. I've finally got pictures so as soon as my friend e-mails them to me I can post exactly what I did.

[mx3man83]

Yes, the Je50 vaf comes stock on an mx-3 GS.

[lakersfan1]

Originally posted by mx3man83:
Good luck trying to move the brake booster. I don't believe it has or can be done. I just modifed my klze throttle body and tilted the engine slightly forward to make the straight neck IM fit. If the IM on the kf an klze are similar then maybe what I have done would be helpful to you KF guys. I've finally got pictures so as soon as my friend e-mails them to me I can post exactly what I did.

From the pictures I've seen, it looks to me like the throat of the KF-ZE intake is thinner than the KL-ZE. That could be an illusion, but if it were true, it might mean the extra couple millimeters of clearance would be enough to clear it. Anybody had the KF-ZE manifold up next to a KL-ZE straight neck manifold to compare?

[lakersfan1]

Originally posted by mx3man83:
Yes, the Je50 vaf comes stock on an mx-3 GS.

Sweet. So it sounds like there's nothing that's necessary to buy for MX3 GS owners for proper operation aside from the engine and ECU, then experiement with intake manifolds? Sound about right?

<small>[ March 22, 2004, 05:36 PM: Message edited by: lakersfan1 ]</small>

[mx3man83]

yup, the engine and ecu is all you will need if you already own a GS. If the throttle linkage on the kf is anything like the klze and kl03, a couple of millimeters won't give you the clearance you need. The throttle linkage is a two step deal. I don't know how to explain it perfectly but ill try. On the klze and kl03, the throttle cable does not hook directly onto the butterfly, it hooks to something else, which is in turn hooked onto the butterfly linkage. Because of this, the butterfly linkage sticks out way past the end of the throttle body. On the k8, the throttle cable hooks right up to the butterfuly linkage, which is how i have my klze throttle body modified.

[Mnemonic]

the neck on the IM is a bit shorter than the neck on the klze, but modifications can be done to get the shift linkage to clear just in case, but really the best thing to do is go with the millenia IM because of the square runners you get better airflow, you can have it portmatched for probably around 50-100 bucks and see around a 5-7 increasement in hp not to mention having better air flow, the optimum thing to do would be to bore the TB with the Millenium IM then run some 3" piping for your CAI, you can get a CAI kit off ebay for a Prelude and do minor cuts and it fits best thing is the kits are 30 dollars.

As far as the ecu goes, ive herd you can use the k8 i know dave is using the kl and his seems to be running pritty well, i beleive since this engine is in the middle of the 1.8 and the 2.5 that both ecu along with the stock will work quit well, the only thing i could see that would be effecting is the gas, which you can pick up an safc on ebay from 100-150.

[lakersfan1]

Originally posted by Mnemonic:

the only thing i could see that would be effecting is the gas, which you can pick up an safc on ebay from 100-150.

Why wouldn't you just get the KF15 ECU then? Does it cost that much to get a KF15? I was hoping the ECU would only run $100, maybe $150 in the first place.

[lakersfan1]

Originally posted by Custommx3:
I agree. I have the KFZE and have yet to put it in. I was told you cannot use the k8 headgaskets.
My heads are k8101, J NumoniK are k82.

Brian (J NumoniK) said that he compared the two gaskets and they indeed were different.

I thought the KF was the same bore as the KL, but the same stroke as the K8? So wouldn't that mean that KL head gaskets would fit the KF?

[Custommx3]

Its a slight difference between a k8 head. I think the bore is a bit different. Rememeber, its a 2.0L.