300/440/550 550 topend is here, got a few questions

S

SuperDave4x4

Location
Athens, GA
I got a 550 topend sitting on the floor that will be going on my 1989 440, all I need is to have the cylinder honed, new piston rings, and a base gasket and head gasket. My questions are:

Which base gasket should I get? Stock material or is there something better?

I was going to have the head milled, but I won't have the correct squash band so I want to use a copper head gasket so that I can increase the cylinder PSI, but isn't there a trick to installing one?

Lastly since I will have my cylinder honed, will stock 550 piston rings be fine?

I'm setting this ski up for me as a beginner freestyle/freeride.

Thanks for the help.
 
Talsivar

Talsivar

X-
Location
oregon
the copper head gasket leaks easily. i don't understand why you cant have someone shave the head? if you have stock pistons and not overbore then you need stock rings. the 440 case will fit the stock 550 piston if i remember corectly but at one of the overbores it won't fit anymore without cutting the cases.
 
S

SuperDave4x4

Location
Athens, GA
Talsivar said:
the copper head gasket leaks easily. i don't understand why you cant have someone shave the head? if you have stock pistons and not overbore then you need stock rings. the 440 case will fit the stock 550 piston if i remember corectly but at one of the overbores it won't fit anymore without cutting the cases.
Click to expand...

I could have some one mill the head locally, but i've read where if you go that route the head wont have the correct squash band and could cause some major problems. I may just give them a call and ask them about the squash band. Hell i don't even know what a squash band looks like.

I also have stock pistons and I'm not going with a full on bore, just honeing it to clean the walls up.

EDITED
 
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Talsivar

Talsivar

X-
Location
oregon
there are plenty of reputable shops that can do it correctly. also make sure you have a good crank if your going to raise compression. raising compression could end the life of an older worn crank.
 
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S

SuperDave4x4

Location
Athens, GA
Well through my extinsive searching on other sites I've found that 440/550s dont have a squash band since the piston never goes above the deck of a stock cylinder.

Talsivar how am can I check my crank to ensure that it is still good?
 
Talsivar

Talsivar

X-
Location
oregon
wiggle the rods back and forth up and down it should be tight with little or no movement. bearings should spin quietly without noise or bearing chatter.
 
S

SuperDave4x4

Location
Athens, GA
thanks for the help Talsivar.


I call around today about getting the cylinder honed and they want 20 bucks per hole. So I call my buddy who's cousin builds drag motorcycle and runs his own machine shop and he's gonna do it for $10. I just have to wait till I go back home so I can take it to him. Also I think I'm going to run a copper head gasket and mill off no more than .02 from the head. That will give me a grand total of .04. I may just only take of .01 since the motor is a little old stay on the safe'r side. Plus that will ensure that my head is completely flat.

Its going to be a slow process, but it will become a little freestyle ski some day. Next I'm looking at an exhaust or an impeller for freestyle. I'm thinking a striaght 13. Will that be too much or should I go with a straight 14 with the 550 motor?
 
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