OMC 3 Cyl expansion Chambers

**ima75man** · 03-04-2009

fast fred, give me a call dude.

**johnsonracer** · 03-04-2009

I cant imagine that the factory would grind the exhaust bridges so thin that they break..... like 0.075" thin

**850cc racer** · 03-04-2009

i dont have my rule book with me, however i know Tim Bollins has the aus speed record.. 103.99mph

and i'd imagine thats with a 31M.. i can email him and check if need be!

Originally Posted by johnsonracer

I want the New Zealand F3 speed record.

Currently its held by a Hydro with a 1650cc inboard. A tunnel has gone 92mph in NZ in a kilo. No one thinks I can do it, but I'm sure you guys and around the world are breaking the 100mph with tunnels.

**Fast Fred** · 03-05-2009

ima75man

**Fast Fred** · 03-05-2009

ya, .075 is thin, new sleeve should be all spec'ed out, line it up,

push it in

bore and deck.

.004 interference fit on the sleeve

**johnsonracer** · 03-05-2009

LA sleeve dont have anymore sleeves or make any more. Bummer

**Bill Van Steenwyk** · 03-05-2009

Some years back sleeves with a different porting arrangement were needed for an engine, and as it is a lot easier to remove metal than add it, "blank" sleeves of the correct diameter and height were purchased with no ports cut in them, and then the porting was done seperately by someone else to meet the need. Perhaps LA Sleeve could furnish "blank" sleeves of the correct dimensions and then using the afore mentioned "port map" they could be finish manufactured. If they are not availiable anywhere else, might be worth a try.

**Tim Kurcz** · 03-05-2009

Did you ask LA if they would make them in small quantities? If they won't, I can make them using a new one I've got in my possession, or from a sleeve removed from your block. Let me know how many you want and I'll quote.

Tim

**johnsonracer** · 03-05-2009

I asked them to supply blanks but havent heard back yet.

3 sleeves are needed Tim. The bottom cyl has been bored out and a thicker sleeve was put in. If this isnt factory I will have to give you diameter needed for that hole.

**Tim Kurcz** · 03-05-2009

You might also try Advance Sleeve Co. Buy a cast iron sleeve(s) with the correct OD, lay them out with the port map, and anybody with a Bridgeport can machine the ports. Also, you and Fast Fred both have examples to work from. Easiest thing to do is wait till your wife is out for an afternoon, wash the block in your dishwasher, bake it to 350F, then turn upside down in a wood box (to catch the sleeves as they fall out). The house might be a bit smelly, especially if castor was run in the engine. Anyway, once your wife is done giving you Hell, just take your best sleeve and the blanks to your machinist. While the block is empty, you can clean up the transfer & boost passages. Good luck!

Tim

BTW Installation is just the reverse. Just make sure you weight the sleeves while the block is cooling to keep them from creeping up. About 5# per sleeve will do it.