hello,
has anybody tried to bore H23Ax or H22Ax to 90mm?

 

If I read correctly, pocketrocket racing has done this. Look up the name, they are here on H-T. Im not sure how they did it though!

 

Yes, but you'll need to run a MID style sleeve.

 

hu: Pocketrockets racing - awesome!!! up to 93mm bore!! I would love to see this monster!

PrecisionH23a: yes, sleeve is one choise or I can have nikasil on the cylinders.

thanks for your posts, do you know anybody running bigger bore than stock on H series engines?

 

the h22/h23 block cylinder walls are not nikasil, so boring it to 90mm and coating it with nikasil would be pointless. plus you won't find any pistons that wouldn't chew the crap out of the none iron sleeves

 

Stock walls are FRM with nikasil. As I said, you will need a MID style sleeve.

 

I know, stock cylinders are FRM but not with nikasil, FRM and nikasil are two different technologies (I think, if not, correct me).
I wrote that when I bore H23 to 90mm and then I can have nikasil on the walls, I mean without sleeves (I know company repairing aluminium blocks with nikasil cylinders from bikes). You think there is not enough material for this?
A lot of the pistons of this size ride bikes, pistons should not be a big problem I think.

 

I believe your theory would work, however the cylinder walls are just too thin to bore it out that big. It would come very close to breaking into the water jacket.

I dont see why a nickasil coating would hurt, alot of bikes and stuff do use it and they see way more rpm than any of cars most likely will.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hu &raquo;</TD></TR><TR><TD CLASS="quote">If I read correctly, pocketrocket racing has done this. Look up the name, they are here on H-T. Im not sure how they did it though!</TD></TR></TABLE>

He uses a different bore spacing to be able to get bores this big without running into each other. Then youre prolly looking at a custom crank and rods too.

Props for some badass engineering though!

 

stock walls are FRM, a composite material of aluminum, alumina fiber and carbon fiber. factory bore center's is 94 mm
boring the cylinders out to 90mm and then applying nikasil appears an ok idea at first thinking, but in reality, the original structural rigidity of the aluminum matrix honda walls has been lost and nikasil will not replace this.....if you want to bore it out....the MID kit from Darton works well...We use Darton custom ductile iron sleeves and have never had an issue with them......

obviously, the 92-93mm bore is not achieved with 94 mm bore centers!

this is a our "standard" sleeved block with 87 mm bore, but it shows a decent idea of how it can be bore to 89,90mm....


90mm for long term street use is not the optimum choice, if using a MLS head gasket from cometic........, cometic ceased production of the 90mm head gasket based on the their embossment size.

 

to all: thanks all for comments, probably it will be better to use sleeves (according to your advices) than make experiment with nikasil...

to PocketRockets Racing: what is value of bore pitch you use for 92-93mm bore?
which crank shaft do you use for this engine? stock H23 crank shaft? or modified h23 c s? or something else?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PreludeZ &raquo;</TD></TR><TR><TD CLASS="quote">to PocketRockets Racing: what is value of bore pitch you use for 92-93mm bore? </TD></TR></TABLE>

I could tel you but I would have to kill you.....LOL

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PreludeZ &raquo;</TD></TR><TR><TD CLASS="quote">which crank shaft do you use for this engine? stock H23 crank shaft? or modified h23 c s? or something else?</TD></TR></TABLE>

Crower made in the USA Billet 100 mm stroke....all specs decided by me.

 

PocketRockets Racing:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PocketRockets Racing &raquo;</TD></TR><TR><TD CLASS="quote">
I could tel you but I would have to kill you.....LOL
</TD></TR></TABLE>
OK, I understand
Thanks anyway for all your advices

 

assuming your talking about a closed deck h series,you can use dartons ductile iron flanged replacement sleeves and bore to 90mm, some have said 91mm as a last resort. i have a cometic 90mm h22 headgasket in my hands right now, there is barely any embossment left. no way i would try this for a street motor, just not enough room between cylinders to keep a gasket in it for long. but we shall see how many passes it will last at the track!

cometic will make any size gasket you need

 

what about a copper gasket with o-rings? would that be a better for a 90mm bore?

 

o rings work, but alot of work to do.