We noticed a weak engine in the last rounds of LCE.
But in Assen we had a totally breakdown of our Honda.
First we thought of worn out pistons, but then we found the reason for excessive blowby.
cracks between 2nd and 3rd and 3rd and 4th cylinder.
First we thought of a simple sleeve, but now we got the message, that our whole block broke apart 
Even a drilled hole couldn�t stop the scratch.
anybody ever has seen something like this at a Honda block?
No that cant be a Honda engine, theyâre indestructible arenât they??? 
I think it happened when following a red Audi-Exige in Donnington last year
Back to a Rover K for you 
I Think we will build up a RoverK for the future, but now we get a new block sleeved by ERL and we downsize our engine for the 2011 regs of lotustrophy. Less aggressive cams, only single throttle intake and konservative mapping (ignition)
Hope the Honda lump stands the next season with the downgrade.
Peter
Is that K20 of yours standard bore diameter ?
its a little more bore (i think 87mm)
So itâs less of a question about âhas anyone seem this beforeâ and more âwhatâs the spec and who was paid to do the work in the first place.â
Standard block - very unusual to see this, badly bored block, very common mode of failure.
@ johnboy
Where can you see that it was a âbadly bored blockâ?
Can you tell me more details about the âvery common mode of failureâ?
That looks to me like the cylinder walls are too thin. How much metal was there in the bore walls?
it was a 87,5 bore before
the pictures are after ERL bore cylinders ready for sleeving.
Hmmm
That explains something then as that machining is not great quality - so they machined the standard cast in liners to accept sleeves for a 87.5mm bore?
I thought you could only machine the existing liners directly to 87.5mm - no sleeves and if you go bigger you need new liners.
not really - we machined the liners to 87,5 in standard cast
after these break we sent the block to ERL for sleeving. with sleeves there are 90mm bore possible.
i thought, that they machine the whole standard casr�t away, but it seems as they need the standard cast to fix the sleeves.
well here are some pictures of the standard block and a properly bored block.
You can play âspot the differenceâ if you like.
The Darton Sleeves did not really proved to be the best solution for a Honda race-engine. These are the DARTON experiences we have here in central europe:
you have to cut too much material from the crank-bearing therefore the block is weakened in these areas
the Darton sleeves seem to be of weak material, as the get oval and cone-shape after some time (on the top 0,04mm wider than on the bottom)
you get problems with headgasket, as the gasket is pressed on the sleeve + the block (different to the OEM)
So we will use ERL Sleeves although these are more expensive as the DARTON ones.
Would be interested in your experiences with DARTON sleeves.
regards
Peter
I donât think anyone has got anything against ERL, more the case that the image you posted up looks like an atrocious install.
Dartons have to be very carefully installed to exacting specifications - see http://www.darton-international.com/Honda%20Manual.pdf but as you have discovered so do ERL sleeves.
A bodged Darton will break, a bodged ERL will break.
You need to be asking exactly what machinery was used and what methods/procedures were followed by whoever did your engine work. Its that simple.
Ultimately once you crack open an engine like a K20 and start messing reliability will be the first thing you loose but the benefits should presumably out weigh that or its just not worth the time, expense and hassle.
Darton experience here seems pretty good - I know of 5 cars in the elise/exige swap community running them with no issues at all. Scuffham raced his for 3 years IIRC without significant issue and thats a lot of race miles.
Prob the most experienced in their use I know of is Ian at Clockwise motion - he does at awful lot of built engines mostly outside of the lotus community so I have no direct experience of his results other than his customers seem to win an awful lot and he has a great reputation which speaks for itself.
Scuffham and especially Ian from Clockwise Motion are good reputation for DARTON, but Kaps Roman from ECU-Performance has to throw away two Darton sleeved Blocks and therefore changed to ERL. Maybe its only philosophy
One thing seems to be common: endless waiting for delivery ((
Peter
PS: I never wanted to set DARTON-sleeves on the EAGLE-level, because these proved to be real bullshit!