komatsuvarna
Arboristsite MVP
sounds about right. If it has new rings it will probably come on up some.
372 xp first ever porting rebuild
- Thread starter Chesterewers
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sounds about right. If it has new rings it will probably come on up some.
Chesterewers
ArboristSite Member
yup new rings, I have it running slight rich right now, is that recommended for the first 10 hours until the rings set? I am happy, the walkerized muffler sounds great. JW just uses deflectors welded on with screen now. I am not sure why he went away from the pipes.
RiverRat2
Serio Tree Freak
deflectors are faster and require no welding just cut and drill,, done!!! I guess they are cutting down on overhead!!!! LOLOL!!!
Post up some vid of that Hoosky!!!!!
Chesterewers
ArboristSite Member
video
I got a few videos now I tried to upload one here but this site says file too large, its not that long. I may have to get a youtube acct. I hate signing up for acct. on internet anymore used to be easy now there are capthas everywhere and password strength is always weak then once its good enough I forget them and have to start all over again. I can never remember the secret question because its never a relevant question to start with so I just make something up. Internets..... I hope to post a vid soon.
I got a few videos now I tried to upload one here but this site says file too large, its not that long. I may have to get a youtube acct. I hate signing up for acct. on internet anymore used to be easy now there are capthas everywhere and password strength is always weak then once its good enough I forget them and have to start all over again. I can never remember the secret question because its never a relevant question to start with so I just make something up. Internets..... I hope to post a vid soon.
Chesterewers
ArboristSite Member
first tank of gas in it
Thats true from now on on muffler mods I'll just do em myself, here are a few vids of it cutting with 7pin sprocket have an 8 on the way, this is dried red oak. First tank of gas, just tuned the carb to what sounded right may still be a little rich, I would love to buy a tach if I can get one reasonable. Oh and i'm running 40:1 I am not sure if others run 50:1 after porting or not? Sorry for the dark video its in a shed trying to keep the wood dry out of the snow.
YouTube - 372xpw cutting red oak‏
YouTube - MOV01547‏
YouTube - MOV01548‏
Thats true from now on on muffler mods I'll just do em myself, here are a few vids of it cutting with 7pin sprocket have an 8 on the way, this is dried red oak. First tank of gas, just tuned the carb to what sounded right may still be a little rich, I would love to buy a tach if I can get one reasonable. Oh and i'm running 40:1 I am not sure if others run 50:1 after porting or not? Sorry for the dark video its in a shed trying to keep the wood dry out of the snow.
YouTube - 372xpw cutting red oak‏
YouTube - MOV01547‏
YouTube - MOV01548‏
Chesterewers
ArboristSite Member
xpw
this is the 51.4cylinder for an xpw saw so thats what I am calling it now but the saw was a 372xp 08 model.
this is the 51.4cylinder for an xpw saw so thats what I am calling it now but the saw was a 372xp 08 model.
Chesterewers
ArboristSite Member
box elder
Heres a vid of me using it to cut box elder, didn't have the best place to stand on a hillside.
Heres a vid of me using it to cut box elder, didn't have the best place to stand on a hillside.
AUSSIE1
Al.
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Hi Chester...how are ya mate?
Chester, are you running a base gasket or sealer?
Can you fit a degree wheel to this saw so we can check your numbers? Once fitted, we will take you through the process and see what you have.
Chester, there has been some nasty BB kits occasionally, but mostly good and when there is an issue, Bailey's come good, so you can't go wrong. These are the best way for someone to learn some porting on. Good nick OEM and especially the 51.4cc are not for practicing on. Some say go for it, but I've seen some nice cyl end up as ashtrays as Will has pointed out. I started out with the BB kits and put the OEM's on the shelf till I had a fair idea as to what I was doing.
If you can afford a BB kit, grab one, forget the degree wheel for now and do some widening and lower transfer work.
Post a heap of photo's and ask a heap of questions before you do anything. Peeps here will help you along the way.
Leave degreeing and timing numbers for the next level.
Chester, are you running a base gasket or sealer?
Can you fit a degree wheel to this saw so we can check your numbers? Once fitted, we will take you through the process and see what you have.
Chester, there has been some nasty BB kits occasionally, but mostly good and when there is an issue, Bailey's come good, so you can't go wrong. These are the best way for someone to learn some porting on. Good nick OEM and especially the 51.4cc are not for practicing on. Some say go for it, but I've seen some nice cyl end up as ashtrays as Will has pointed out. I started out with the BB kits and put the OEM's on the shelf till I had a fair idea as to what I was doing.
If you can afford a BB kit, grab one, forget the degree wheel for now and do some widening and lower transfer work.
Post a heap of photo's and ask a heap of questions before you do anything. Peeps here will help you along the way.
Leave degreeing and timing numbers for the next level.
parrisw
Tree Freak
I agree with al here. Can't go wrong with this advice.
Chesterewers
ArboristSite Member
Thanks
Hi doing well, I agree good advice, for this saw its already all ported out I took a few pictures, intake and exhaust were 160 on timing, ex honestly may have been only 157-58 but I did bevel and didn't measure after that so I don't know if it changed or not, 2nd tank in it today cutting more red oak it is tearing through it better than stock for sure. So true I could have ruined a cylinder but it looks okay so far, did widen a bit also on ports did uppers. Thanks how does the carb sound alright or too rich? BB kit would have saved me 150 bucks, should have went for it almost did but had a bad bb kit 3 years ago so I was scared of it. Thanks mate.
Hi doing well, I agree good advice, for this saw its already all ported out I took a few pictures, intake and exhaust were 160 on timing, ex honestly may have been only 157-58 but I did bevel and didn't measure after that so I don't know if it changed or not, 2nd tank in it today cutting more red oak it is tearing through it better than stock for sure. So true I could have ruined a cylinder but it looks okay so far, did widen a bit also on ports did uppers. Thanks how does the carb sound alright or too rich? BB kit would have saved me 150 bucks, should have went for it almost did but had a bad bb kit 3 years ago so I was scared of it. Thanks mate.
Your saw is not turning near the RPMs I would expect for a ported 372. I can't tell for sure, but I don't know if it's even turning stock RPMs. Do you have a tach? If so, you should be seeing around 15,000 RPMs. Have you replaced the coil with an unlimited one? How wide did you go on the ports, intake and exhaust? Did you do anything with the transfers? Did you window the piston after raising the cylinder walls? So both the intake and exhaust have 160° duration? Where are the transfers? Post up the details, and we'll help you sort it out.
Chesterewers
ArboristSite Member
saw
I don't yet have a tach, thats my next step is to get one, I richened the saw up quite a bit on the carb just to be safe running. I widened the ports also, maybe .15'' just until the bevel that was on the port was gone then stopped, the piston is stock nothing done to that, no base gasket enlarged the transfer ports ground those all out knife edged it, changed timing on intake and exhaust until it was at 160 degree duration, didn't change timing on the transfer ports tho because I could not reach it with any tools. The coil is rev unlimited so if I lean out the carb it will turn more rpm, tested compression after it was together and it was at 150 I plan to test compression again later on. I figured the rpm is okay a little slow at the start and I can always lean it out once the rings are set in.
I don't yet have a tach, thats my next step is to get one, I richened the saw up quite a bit on the carb just to be safe running. I widened the ports also, maybe .15'' just until the bevel that was on the port was gone then stopped, the piston is stock nothing done to that, no base gasket enlarged the transfer ports ground those all out knife edged it, changed timing on intake and exhaust until it was at 160 degree duration, didn't change timing on the transfer ports tho because I could not reach it with any tools. The coil is rev unlimited so if I lean out the carb it will turn more rpm, tested compression after it was together and it was at 150 I plan to test compression again later on. I figured the rpm is okay a little slow at the start and I can always lean it out once the rings are set in.
Chesterewers
ArboristSite Member
tach
I was looking at ebay for a tachometer, selling 15.00 including shipping out of china they have one, I'll probably go for one. It should help get the rpms up there as I lean the carb back out, im a bit afraid to do that part without the tach wouldn't want it too lean.
I was looking at ebay for a tachometer, selling 15.00 including shipping out of china they have one, I'll probably go for one. It should help get the rpms up there as I lean the carb back out, im a bit afraid to do that part without the tach wouldn't want it too lean.
Widening the ports to 65-70% of bore is the most important piece of the porting puzzle, more so than the port timing changes you made, IMHO. I believe you left quite a bit on the table if you only took it out to the bevel edge. Sounds like you're on the right track though.
Chesterewers
ArboristSite Member
Thanks, it was hard for me to know how wide to go because from other reading it was suggested to go .10'' I will have to go wider than and see how it works out. I read others saying to go as far as possible before the edge of piston skirt? The hardest thing is knowing for sure until it is done unless someone comes along and tells it from their experience thanks for the help.
I'd recommend going 65% the width of the bore. If not able to due to skirt width or ring end locations, you can go within about .050" of skirt edges. Just make sure you know exactly where the piston rides in the cylinder. I carefully mark the piston on the edges of the exhaust port before doing my layout.
parrisw
Tree Freak
How do you mark the piston skirt edge on the bore? I mean its not like you can stick a pencil in there when its together.
No, I mark the piston skirt through the exhaust port. That way I can re-index the piston in the bore, once disassembled, and mark the skirt edges on the cylinder wall.
parrisw
Tree Freak
Ahh, I see. I pretty much do the same thing. Except I only ever widen to .100" to skirt edge.
AUSSIE1
Al.
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These are excellent for getting right into the corners.
Chester, don't use a tach to tune the saw. Tune by ear with some "4 stroking".
Chester, don't use a tach to tune the saw. Tune by ear with some "4 stroking".
