427

iTrader: (3)

Not positive about Erics problem, but I have had problems with long sleeves in the ls series of engines that first showed up with the LA sleeves in the early years and the C5R . The unsupported sleeve that hangs out of the aluminum at the base of the bore does not want to "keep up" during the honing process and ends up small. This seems worse when the sleeve has rod clearance cuts. I think the outward honing pressure from the stones is pushing out on the unsupported sleeve.

Kurt

Steve - Race Eng

iTrader: (1)

Kurt,

You are right about the unsupported sleeve springing away from the hone. That's why we kept the Darton liners at 5.800". The eight inch sticking out is not an issue.

The aluminum LS blocks have a 6.25" dimension from deck to main webbing. A 5.800" sleeve length leaves .450" for over stroke of the hone - actually slightly less for clearance. That is enough for most machines even those with manual honing heads to get the bottom of the sleeve to hone out. The higher end, diamond hones will do the job with a lot less over stroke but you won't find them in most shops.

Steve

racer7088

Anyone can hone a long cylinder! You only have so much honing overtravel though in any given block at the main webbing.

You can't hone any 6.375 inch long cylinder in an LS1 block though at stock deck height because the hone will crash into the main webbing big time as you wont have ANY overtravel.

The 6 inch long cylinder in a C5R is already a POS to get at the bottom as anyone that hones them knows. Half the ones we have gotten are like .003-.005 tight at the bottom!

We've had other bozo's mow out the radius at the main webbing taking away half the strength out of this area as well since they are gouging it with the lower shoe on the CK10 etc.

Not saying you are doing this mreperf but just that you are very unfamiliar with these blocks I guess. There is only a finite amount of room and you need to have suffcient overtravel to hone them correctly or they will pinch way in at the bottom.

racer7088

The diamond hones use even more pressure so I think it would certainly be even worse with them and people have told me that as well. I make special stones to dwell down there and keep it from getting crazy which would cost a huge amount on a diamond deal. With vitrified stones you can make some extra short stones and just dwell them in that area before it gets bad.

racer7088

Yep exactly, the cylinder "breathes" at that area and rebounds back in instead of staying rigid and being cut away by the hone so it ends up tight.

LS6427

iTrader: (2)

So how about using those 6.350" long sleeves in the LSX iron block to be able to get a 4.250" stroke for a strict N/A engine? With a 4.185 bore.

.

mreperf

I'm very familiar with these blocks and when boring it for the liner it never removes material the bulkhead espcially with the window already there in the main web. The only reason the sleeve is that long is because I bottom it out against the bulkhead, not because it's going to stay that long. The cyl. only needs to be .500 longer over stock to support the piston skirt and honing that amount unsupported is not hard at all to get perfect.