Engine has scored cylinder walls. Been told it needs to be rebuilt. If unable to be honed, understand it will need sleeves. Any suggestions for which sleeves to go with? Do the sleeves last?

Thinking about sending the block to Inline Pro. Anyone had them sleeve a block?

From borescope

 

Sleeves are for forced induction. They are a huge compromise otherwise, and really only suited to high levels of boost.

You can either buy a used motor, or there is a company, can't recall the name, that can reapply the frm coating. They exist as a rebuilder of modern, but rare motorcycle engines, that use similar cylinder wall coatings. They've done S motors before.

I don't know how much it costs, but imagine its prohibitively expensive. Hence most just getting a used motor.

 

Such as?

anecdotally, B-series motors seem to handle sleeving just fine (I honestly know diddly bout the B-series, just seen a few of them driven hard over X number of years). Granted the F is a different beast but I'm still trying to process why sleeving the F is so much harder. I understand the different materials (sleeve vs block) have different thermal properties. What else? Why does it work in others and not here? Don't the boosted guys sleeve their engines? Or is it "They're making big HP so they expect to have lower life span" type of argument?

 

Wondering the same, why do sleeves have such a bad reputation for the f20c. Anyone have high miles on sleeve block? Hard to find a good engine. Would like to save the one I got.

 

Sleeves bring 2 issues: 1st, they don't transfer heat as well as the stock FRM material; 2nd, they require the use of 2618 forged pistons which are strong but will not give you the longevity of the OEM parts.

The company name is Millennium Technologies. They replate the bores with Nikasil and bore it out to accept any aluminum piston you want.

 

I always thought the OEM FRM liners were designed for a reason , high rpm NA setup, low friction and good heat transfer and durability, etc. But we know the oem sleeves still ovalize after some length of time and use. Aftermarket sleeves work great with boosted applications. I am sure you can build a high rpm motor with the proper aftermarket sleeves and pistons and other parts, the trick is finding a good engine builder who has experience with these motors. I know the Acura Integra Type R motor does just fine without FRM but it is not the same as the F20 obviously.

 

Let's remember also, that FRM bores by design showed less deformation than steel lined cylinder walls in Honda's R&D program for FRM.

To test this, I put together an engine with non-damaged used bores and a moderate mileage block without honing or boring and it burns ZERO oil and has excellent compression.

As for putting together a reliable engine with sleeves.. it is very doable but won't go the length of the OEM stuff (100k miles min).

 

There has to be a reason for this kinda exotic coating. May have come from Honda HRC's experience in high-RPM racing bikes?

My little CR125 could rev to the moon. Never blew up, once.

 

Honda R&D Co. Explained that they used FRM for weight savings, cooling system compactness (less pumping loss), durability/longevity, and easy to machine in a cost effective manner vs Nikasil/Alusil.

 

uhhh, that first sentence is not true what-so-ever. A steel sleeve with have significantly less distortion than a pure aluminum sleeve.