KB block 4.80 bore spacing

What's the largest bore I could run with sleeved KB solid aluminum block? Currently sleeve OD is 4.64 something and cylinder bore 4.28

Would it be possible to run 4.5" cyl bore, what would be the correct block bore in such case?

Like to build 572 cid (4.5 x 4.5) but don't know if I can do that with 4.80 bore spacing.

Any help appreciated.

 

I have a Stage VII tall deck that is bored 4.510, so yes it can be done. How strong the sleeves are at that thickness, I have no idea, I bought this short block from a pro-mod racer in GA, got put on the back burner when my mom got sick with cancer, still sitting on the floor looking for a home as I wound up putting a blower deal together for my altered. I know the guy I bought it from was building some big inch Nitrous (for Hemi's anyway, 690"+) motors with 1/2" spacer plates on top of a 1/2" tall deck block and was getting special extra long and oversize OD sleeves from KB, although I don't know the OD measurements, I believe he was running around 4.560" bore. He was always a little tight lipped about his combo as he was pretty much in No'Mans Land against all of the Merlin guys running 30 cubes more but I still occasionally get an e-mail from him. I'll try to get some info out of him the next time I hear from him. BTW what usage are you looking for, blown or N/A??

 

KB block

I am planning on running N/A with enderle fuel injection system and Speedtech nitrous system. If I can build a 572 cid engine, that would be great, but a guess smaller cid is also an option. Like to get a 4.5" stroke crank into the block and then run what ever cylinder bore is safe.
I have some old BAE fuel heads and sheetmetal tunnelram intake with a hat.

Thanks

 

I do believe you would be safe with a N/A nitrous setup at 4.50" bore in a solid block. On the other hand, being budget minded, I would hate to see you bore that much out of a 4.280 sleeve and not get more use out of it. N/A Hemi pistons are already heavy and only getting heavier with the larger bore. Also you don't have as much of a valve shrouding problem with a smaller bore Hemi as you would with a same bore wedge motor, so other than total cubic inch gain there is really no other major advantage in going big bore Hemi in my opinion, but a lot depends on what type of racing you doing, how much you want to turn the motor, how much between round maintenance you're wanting to make, etc. Not trying to talk you in or out of anything, just something to think about.

P.S. One thing to consider is the chambers on those fuel heads are probably matched to a 4.190" or 4.250" bore. Just have to keep that in mind when ordering pistons.

 

Spoke with KB racing today, and although it is possible to bore the block to 4.699 and install corrsponding sleeves to obtain the 4.500 cylinder bore, I start to believe that it is not the best interest for me to go this way.
As I said earlier, I am new to Hemis, but really like to build a killer combo that is easy to maintain and easy on parts.
Maybe I will settle for a few less cubic inches and have a more reliable engine.

Thans for the help. Bet it won't be the last time I need to consult you guys.

By the way, the hemi will go into a Volvo...LOL