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The reason no one uses the K8?

Posted: May 23rd, 2010, 4:56 pm
by RedAutobotMX3
Ofcourse we've all heard and would like to do the klze swap with the mx3, but since the stock k8 is there, can it be bored out to say 2.4 and make comprable power with the same headwork and other tuning/performance enhancing items as the kl series motors? I haven't seen too much about any major modifications for the stock k8, which leads me to believe no ones uses it cause either: 1. There's not enough size in the cylinder walls to bore out 2. It wouldn't necessarily be worth it in gains vs the money you would spend on the kl swap 3. Or there are no parts available and not enough of the kl parts such as valvetrain can be used in the k8.

In summation, is there hope to build a nasty K8 or is it all really about the klze/de?

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 5:01 pm
by onlytrueromeo
ALL three of your guesses are correct.

ZE swap = $1500 for engine/clutch/fluids/wires/etc, less if you have extra stuff and have done it before.

Show me an engine build that will net 70HP for that price or less. Only other options are turbo/nitrous, and both have their obvious drawbacks. Sure a k8 can be turbo'd to be faster than a ZE, but it's going to cost more than $1500 and not be as easy/reliable.

ZE/DE swaps are the easiest and most productive swap for the V6 Mx3, period. Anything else will require custom work and the costs will far exceed the benefits IMO.

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 5:04 pm
by mikeinaus
try search. from what ive herd the cost/performance gains of the k8 arent really worth it.

there was a guy from somewhere in europe a few months back that was modifing his k8. i think he got it over 140hp without any major modifications.

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 5:52 pm
by stereoking15
boring out to get performance is not always the best becasue then you limit the cylinder wall thickness and compromise the sleeve integrity and if you do by chance bore one out that big you need to get a head gasket to match the amount of gross overbore. the klze/klde get the displacement diffeerence in the stroke more then anything but do almost have a 10mm larger piston diameter then the k8. So, if you were to do something of that nature use those pistons and possibly the head gaskets ensuring that all the oil and cooling jackets line up

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 6:26 pm
by Nd4SpdSe
RedAutobotMX3 wrote:I haven't seen too much about any major modifications for the stock k8, which leads me to believe no ones uses it cause either:
1. There's not enough size in the cylinder walls to bore out
2. It wouldn't necessarily be worth it in gains vs the money you would spend on the kl swap 3. There are no parts available
All of the above

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 9:47 pm
by Mooneggs
I LOL when I saw the title of this topic :) To the OP: you have answered your own question!

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 10:09 pm
by RS_OBD'oh_2
$10,000 Plus in engine work is better how? When the engine is at the shop, you can drop in a ze.

Top ten worst ideas ever

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 10:16 pm
by solo_ryder
K8 FTW

Re: The reason no one uses the K8?

Posted: May 23rd, 2010, 10:59 pm
by fowljesse
Short answer; Yes, you can make some power with the K8. Shorter answer; Search :lol:
Medium sized answer; It would cost alot more to make power with the K8 than with a ZE, or DE. I would love to see it done. I wonder what happened with that guy that had to keep the K8, to stay within his class, and wanted to make power.

Re: The reason no one uses the K8?

Posted: May 24th, 2010, 1:53 pm
by mazdags94
fowljesse wrote:I wonder what happened with that guy that had to keep the K8, to stay within his class, and wanted to make power.
Didn't he say he'd get beat up if he did an engine swap or something like that and refused to turbocharge it? He'd have nothing left to work with except an ebay HP chip, electric supercharger, and brembo caliper covers.

Re: The reason no one uses the K8?

Posted: May 24th, 2010, 5:01 pm
by RX8SE3P
Unless you got custom camshafts and got the K8 to rev out to 8000 with headers and exhaust, it still wouldn't make the same power as a ZE.

ZE is cost effective, same weight, drops right in, boosts power and torque figures. Best of all, anything you can do to the K8 you can do to the ZE for even more power (headers, exhaust, cams etc).

Re: The reason no one uses the K8?

Posted: May 24th, 2010, 6:36 pm
by valk1317
could you use ze cams on a k8?

Re: The reason no one uses the K8?

Posted: May 24th, 2010, 7:03 pm
by Nd4SpdSe
RX8SE3P wrote:Unless you got custom camshafts and got the K8 to rev out to 8000 with headers and exhaust, it still wouldn't make the same power as a ZE.
The K8ZE has a 7500rpm redline, has square runners, no EGR and only makes an extra 5hp more over the K8DE
valk1317 wrote:could you use ze cams on a k8?
No. You could possible use KF cams since I believe that motor uses a K8 head, but no can do on the KL cams

Re: The reason no one uses the K8?

Posted: May 25th, 2010, 2:23 am
by RX8SE3P
Nd4SpdSe wrote:
The K8ZE has a 7500rpm redline, has square runners, no EGR and only makes an extra 5hp more over the K8DE
The redline has no input on how much power you have up high. An engine might make max power at 5500rpm, rev to 7500 all you want, it won't make much power there. Pretty sure the K8ZE has the same cams, it just has what you mentioned in it's favor, plus postentially being calibrated for 98 octane in japan.

Re: The reason no one uses the K8?

Posted: May 25th, 2010, 8:57 am
by mazdags94
If you ever did boost a K8, the nice thing is that if you blew the engine, you could always directly swap over the turbo parts to a DE.

IMO, the KL engines have the highest potential for the mx3 for the money. But it's been said already so this is just a support post.