K8 Piston idea

[ER Autobedrijf]

Hello,

I have read somewhere that it is possible to bore out a K8 to fit KL pistons.
Now my question is: Can it be done?? Looking at the amount of "meat" that is on the orignal cilinders there is a lot of material that looks like it can be removed.
I know that it is easier to just put in a KL, but we are stuborn dutch people and we want to try the hard way
I have tried searching here but have not found anything. So sorry if it already has been asked

Greets

[MrMazda92]

If it is possible, the cost would greatly outweigh the benefit...

I'm 100% for people building a monster K8, but honestly that's not the best road to doing it. I hate to be the devil's advocate, but that's my honest conclusion after putting a great deal of thinking into it myself...

Now, if you want to make big power out of a K8... I do have some ideas for you. Firstly, if you don't already know this, the K8 has a VERY high rod length to stroke length ratio. This lends heavily towards high revving engines, and the very light weight of the rods/pistons(compared to KL equivalent) is a bonus as well.

There is potential for impressive numbers with a K8, definitely. Properly ported heads(not just enlarged ports!!), custom headers matched with custom cams, and rev it to a true 8K limit with confidence it will hold up.

You could even consider SC'ing it or bumping the static CR to 11+:1, honestly the potential matches the funds available. If you can get the heads ported for a decent price, and get 11:1 CR pistons with a lower pin to deck height, using a longer rod to match(less weight, always a plus for high revs), then you would certainly have some bragging rights. It would be cheaper to swap a KL, but there are always options to beef up the K8.

[Daninski]

I'd comment but why,,,just wait for Ryan.

[ER Autobedrijf]

Thanks for the quick response!!

The fact is that because we have a car shop we have a lot of "contacts" who can do all the work for cheap.
So that is why we were thinking, if the block would let us, to bore it out and slap on some KL pistons.
You get a nice 2342cc engine.
We know that it is not the most cost effective way or the smartest way to do but if we can get it to work we do have a one of a kind engine
The only problem is that we don't know if we can bore it out far enough.

[Ryan]

The sleeves are misleading, they are thickened at the top, I doubt you can bore it out to fit a KL piston. Worst case scenario though is that you ruin the block. May as well try it, if you have access to spares.

If you look around for different pistons, say Honda pistons, and find one with the correct type of wrist pin, or maybe even a new rod with a possible match to the crank... there are a LOT of unexplored possibilities. I know there are some Ford 5L rods that fit on our crank, if you can source the 20 under bearings.

But as far as using the KL piston, I think not. KF perhaps.

[mikeinaus]

this guy was using supra pistons and a stroker kit on his k8 viewtopic.php?f=1&t=78428 might be an idea for you... if you made a bored out k8 with a stroker kit, high performance cams and some high reving internals youd have an awesome unique motor.

[marcdh]

Or a possible next stage up from KF could be millenia S rods and millenia S pistons for a 2.3 setup. I'd be surprised if the k8 can take that boring though. If it can it'd probably need new liners/sleeves.

[ER Autobedrijf]

this guy was using supra pistons and a stroker kit on his k8 viewtopic.php?f=1&t=78428 might be an idea for you... if you made a bored out k8 with a stroker kit, high performance cams and some high reving internals youd have an awesome unique motor.

Interesting! But if it was only bored to fit supra pistons than KL pistons should fit no problem. Supra bore=86mm Kl bore=84.5
Or am I missing something???

[Ryan]

That link is likely full of crap.


Supra has a reputation of being fast, and the guy clearly doesn't know what his buddy did, he's just repeating what he was told.

Like the kid who thought he got 250 HP on a K8, 'cause his uncle's dyno said so.

[Nd4SpdSe]

The sleeves are misleading, they are thickened at the top, I doubt you can bore it out to fit a KL piston. Worst case scenario though is that you ruin the block. May as well try it, if you have access to spares.

I've heard many, many, many times that you can't bore out to fit KL pistons in a K8, but can't remember why.

[Ryan]

http://www.xtremethings.com/Engineering ... Sleeve.jpg

[RX8SE3P]

The fact that the KL exists and is a direct swap with next to zero mods required apart from plugging a new ecu in, makes this idea a difficult one to understand.

Best case scenario is getting cams done, headers, porting etc... but even then, the KL engine makes this idea redundant also.

[mikeinaus]

its not hard to understand. he has access to machining equipment and has contacts to get most of the work done for cheap. hes after a one of a kind high performing engine. i can definitely respect that. simply buying a kl and dropping it in is an easy upgrade but its been done to death.

[Nd4SpdSe]

Or a possible next stage up from KF could be millenia S rods and millenia S pistons for a 2.3 setup. I'd be surprised if the k8 can take that boring though. If it can it'd probably need new liners/sleeves.

Can't use the S rods on a K8 requires farily expensive machine work. MrSpanky has/had a K8 that stroked his turbo K8 and he admits that the only reason that he did it is because it didn't cost him for the machine work and the parts were cheap. The S rods won't fit in a K8, I don't remember what exactly was done, but he even said it wouldn't be worth it otherwise. He'd switch to a KL once the K8 blows up. Been years since I talkd to him, so no clue if he even still has his car.

[OutlaW]

loved this thread ... i NEED to turn my K8 into a beast ... im entering a competition restricted on CC ...