Husky 55 Hyway CP timing numbers

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Nitris223

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Just rebuilt a 2007 Husky 55 that I had given to me in a box all torn apart. Crank bearing were toasted along with the cylinder and piston. Did a complete tear down. I had a Hyway CP kit I bought a year or 2 back that I decided to use on this saw. The guy at the factory forgot to finish cutting the squish band towards the combustion chamber and there was a major lip of material left in the center of the cylinder. I have my own lathe so I made a nylon plug and glued 220 grit sand paper on top and slowly cut the lip down until it was flush.
Then I could check the actual squish on the cylinder. With no base gasket I was at .055" and I wanted to use a base gasket. So back to the lathe to deck the cylinder. AT this time I didn't have my degree wheel but I didn't see much point because I needed to take some off the cylinder anyway. Got the squish down to .022" and then had the degree wheel . These are the numbers I got if I did it right. I used a piston stop to find my starting number or TDC.

Intake 72 degrees ATDC
EXhaust 105 degrees
Transfers 121 Degrees
Blowdown 16

Do those numbers sound right. The saws starts and pulls hard and the sucker read 200 psi so I thought my compression tester was screwed up . I grabbed another new one I have and it read the same thing. Went to another saw I knew that read 160 psi last week and it still reads 160 psi. Is this possible to have 200 psi out of this hyway AM cylinder. The combustion chamber does look a bit smaller then the stock OP cylinder. Should I increase the squish . I want a good running reliable saw and don't want to pound the crap out of the bearings . It does have a decomp.
 
Stop complaining. Everyone on here tries to get max compression and then, when you get it, WOW. Use the saw. The 55 isn't a saw to worry about. It is not that expensive. Again I say, use the saw.
 
I am not complaining. Just wondering if it is a bit on the high side for a regular use work saw. Try looking up some of the prices of a used saw in Canada vs U.S. and parts . I don't pick them up for under $200 very often. I am not trying to squeeze the last bit of compression out of the cylinder. Just asked a few questions and learning a bit about porting.
 
Just pulled the cylinder again and looked things over again. Cleaned up the back of the transfer ports. Rounded over the block that is in between the transfer ports because the cylinder is not a true closed port. It is just like the meteor cylinder with the support block between the cylinder. Made the transfer a bit wider towards the intake side and just cleaned up the bevels on the ports because my OCD was kicking in.
Back together and checked timing . Numbers are the same and cold compression is 210 psi. I think I may run a bit of torco octane boost in the gas just for the first tank or 2 to make sure there is no detonation going on. Got the free rev rpm set to 12,200 rpm. See what it does in the cut when I get a chance.
 
If you have the tooling, you could cut a little bevel in the chamber where it meets the squish band to increase chamber volume without altering squish. A little will go a long way haha
 
If you have the tooling, you could cut a little bevel in the chamber where it meets the squish band to increase chamber volume without altering squish. A little will go a long way haha
Are you talking about cutting the combustion chamber bevel a bit bigger. I am self taught on the lathe so I would have to figure out how to hold the cylinder the other way. I guess use a 4 jaw chuck and get it centered or use the mill.
I have just never had a saw with that good of compression. I don't use them much but when I do pull them out I want them to run reliable and not burn down or hammer out the bearings. Of course everyone likes to brag about their hotrod saw but at the end of the day I won't be racing it. It may end up going to my father.
 
Are you talking about cutting the combustion chamber bevel a bit bigger. I am self taught on the lathe so I would have to figure out how to hold the cylinder the other way. I guess use a 4 jaw chuck and get it centered or use the mill.
I have just never had a saw with that good of compression. I don't use them much but when I do pull them out I want them to run reliable and not burn down or hammer out the bearings. Of course everyone likes to brag about their hotrod saw but at the end of the day I won't be racing it. It may end up going to my father.
I am no machinist, amd dont have a lathe, so my advice is from
What ive seen done. If you can picture where the combustion chamber meets the squish band, cut a small bevel there to increase chamber volume without increasing squish clearance or affecting port timing.
 
I am no machinist, amd dont have a lathe, so my advice is from
What ive seen done. If you can picture where the combustion chamber meets the squish band, cut a small bevel there to increase chamber volume without increasing squish clearance or affecting port timing.
Ya I can picture what needs to be cut but trying to hold the cylinder and get it all lined up and centered could be a real pain. Might be easier on the milling machine then the lathe.
 
Opening the combustion chamber is the good way to reduce compression. Raising the squish is the not so good way. Good tight squish clearance reduces the chance of detonation by jetting out at TDC and more throughly mixing the igniting fuel/air mixture, making combustion faster.
 
Mfgr date may be key here - I happened to do the same install this spring - HW 55 CP kit on a 2001 55. Kit was purchased this March.
Pre-porting #s with factory gasket were:
100/123/66
The 66 seemed odd, but it checked out.
Squish? Huge, like .060+.
Tested fine, a little ho-hum.)

Ported mildly but I really focused on flowing the transfers and case matching. There were gains but not remarkably so.
Post #s are 101/124 /76
The 76 was a big change from the original intake number .

Great saws!!
 
So to increase my intake to 78 I could mark the piston with a fine tip marker to figure out how much I need to grind down the bottom of the intake. Keep the bottom of the intake flat also but round in the corners .
 
There's also the option of taking the material off the piston skirt instead of the port floor...

Lot less work...... same results if you're looking for specific timing numbers......widen the port as much as you want/can and cut the skirt to match the width...easy dial in...plus if you fail it only a piston to replace not a cyl.
 

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