Power Tuning

Sometime before the new year I want to buy a 372XP,I have decided not to buy another larger Stihl,the two 44's I have are still on the job after a few hard years but they seem to be falling apart,small things.I don't work on my own saws at all,and really don't screw around with them unless I'm in a tree.I have seven Husky 36s,one Stihl 024,one Stihl 026,two Stihl 44s,one Husky266,one Husky 262,and one monster Olympix,not sure on the numbers,so as you can see I love variety,even got an old Remington???? someone gave me years ago. Question:Has anyone used a 372XP that has been "power tuned"?A shop in Washington does this extra "tuning" for an extra 80$ added to the price of ???They say you wil lose some life,but that you get a better running saw,maybe around 10% more power.?????????????

monkeypuzzle,go to post "help" by the cutter.This has the web sites for Madsens and walkers.I have a Husqvarna 372xp that was power tuned and I am pleased with it.You do gain 10 to 15 percent more power and it runs better than stock.If you go to the site go to the pro saw page and they have saw prices there as well has telling you what they do when power tuning a saw.HUSKY IS suppose to have a385xp coming out,It was rumored to have more power and cutting speed than an 066 ,has well as a lighter package.That is the saw I wanted but has of yet I can't find one.IF you have more questions on the 372 ask and I'll try to help if I can. Dan

From what I have heard if the saw is well taken care of you dont lose any life at all. The engine will run cooler and with the assembly blueprinted any imperfections are removed.

Thanks Dan and Huskyman, I want a (personal saw) so to speak.My two saw guys run the big saws hard,and when I am not around who knows how hard,so I am wanting the saw for when I have a few saws DOWN at once.Since I will be the ONLY one using it I hope I can keep her in tip top shape.Any suggestions on Bar and pitch?thanks again.MP

I use mainly a 20 inch bar,.050 chain,that combination will cut 80% of the trees I log.I also have a 28inch bar,but the 20 will do just about every thing most people.will do.I'm the only person who uses my saws(Im my only employee) which makes it a bit easier to keep them running.The best thing about .050 and a20 inch bar is that most shops will have them in stock,saving down time.The 372 is a very good saw and will last a good 7 years plus as long as you keep things clean and adjusted.there are alot of good saws out there now from more than afew manufactures good luck in finding what you want. Dan

Tree Guy,

Husky shows the 385XP on their website just doesnt have a pic yet so they must be in development and for right now not quite available yet on paper looks to be a real terror in the forrest. Still wont get rid of my STIHL

cut smooth
confused

Yeah it has been on the web site for a couple of months, they better get their rear in gear. Send that one to Walkers and never look back. Though I have never heard of an owner of a 288xp that was not satisfied so if this saw is an improvement then look out 066

Hey HuskyMan,

Everything looks good on paper, lets just see what the 385XP really turns out to be.

Hello monkey puzzle, reading your post on modified 372 xp saws. my shop has been modifing 5 to 6 371's and 372's since they came out five years ago. many of them are still being used after 3 years every day by the fallers . they dont seem to suffer any loss of life because of the modifications we do. I think they last longer because of the modifications we do to the mufflers, they run cooler. we get more on the order of 35 to 40 percent power, a modified 372 will outcut a stock 394 or stock 066.we charge 250.00 to 500.00 depending on whether its a faller's saw or a racing saw. if you want to cut fast it costs more than 80.00 but once you run a fast cutting saw you wont ever be happy with a stock saw. to extract this power you must increase the port timing on the intake, transfer, and exhaust ports. you have to daul port the muffler,and modify the carb. you have to radius all of the ports so the rings dont wear too fast. you have to match the barrel to the crankcase and lower the squish clearance . Anyway, if you have any questions e-mail me at [email protected] Ken Dunn

Hi There all, I think you guys should listen to Ken "The Hot Saw" Dunn. I have had him massage numerous saws, and man let me tell you. It is hard to beleive, but the 40-50% increase is very modest. Running a saw that has been Kennized is the ultimate in sawing. Not trying to knock madsens and walkers, but there is only one place I send my stuff, KDHotsaw. I send him new saws in the boxes and he Kennizes them into nasty wood cutting, neighborhood terrorizing (The Red Beast) machines. I have even dug up some old saws from the 60's and 70's that he brought into the 21st century. The nice thing about getting something from Ken is that you tell him your needs and he will customize the saw to each individual operator. From just a little pepping up to full blown Hot Saws, Ken does it all. Ken is top notch and the only guy I trust my saws with. Thanks, email me for more testimonials, Jonathan

Well it sound to me like what Ken does is a heck of a lot more radical than walkers or madsens. All they do is check all the tolerances and blueprint the rotating assembly and maybe raise the port timing a little. It sounds like Ken does everything short of nitrous and a tuned pipe, which is awesome, but also $500.00 is almost like buying another saw. I cant help but wonder that a saw that modified would be quite finicky about oil mixture, octane of the fuel, outside temp and humidity, etc. If that is not the case then go for it if you have the extra $$$

Well Huskyman it sounds like you've inside a few chainsaw motors. On saws for the woods we don't go that radical. The port timing figures are close to 2cycle kart timing figures. the chain saw motors are basically detuned 2 stroke motors. the manufactures do this to give themselves extra insurance if a person overworks the saw. so with a little work you can increase the power 30 to 40 percent. your right on the oil issue, husky and stihl have both increased oil ratio from 32-1 to 40-1 to 50-1. I suspect this is for better epa emission figures. with all of our woods saws we recommend 30-1 and good quality ethyl gas. since the manufactures went to 50-1 we have been seeing a big increase in big end rod bearing failures and piston seisures. you just can't turn a motor at 10000 to 12500 rpm and get enough oil on these parts at 50-1 oil ratio. also on the dyno each reduction in ratio we see a increase in horsepower.on our racing saws using alcohol we go as low as 16-1. If you want to see one of an example of our work go to chainsaw collectors corner then go to homelite modified saws on arborist site. this is jonathan hobbs (homedelight mans) 2100 hotsaw.In the third picture thats yours truly making a 4.9 second cut in a 23 inch pine . jonathan later changed from a hr191 tillotson to a pair of tillotson 360 gas carbs and picked up .5 seconds Ken

Ken, what is overworking the saw and how do you do it?

Wow, a thicker oil mixture makes MORE hp? For some reason I always assumed the opposite. Is that due to the increased lubrication the extra oil creates? Hey I have a little XL2 homelite that wants 32:1 and a Husky 55 that wants 50:1, can I run them both at 40:1 if I remove the spark screen on the 55? I dont want to kill the XL2 due to running too lean, I really like that little saw. I run Husqvarna XP oil. Thanks Ken

Hello VSTEEL,overworking a saw is basically overheating a saw and causing a piston seisure. saw motors have limited cooling capacity compared to other types of air cooled 2 stroke motors. IF you run a alaskan mill slabbing a 3 ft wide 16 ft long doug fir or cut 1 or 2 tanks of cord wood without stopping or cutting with a dull chain there is a good chance you will overheat your motor. chain saw motors have a limited cooling capacity compared to other types of 2 cycle motors. the motorcycle builders went to water cooling systems because after 10-15 minutes of running they were losing 40 to 45 percent of their horsepower. the saw manufacturers detune their engines, they produce less heat and it gives them a cushion under these conditions . overheating may be a better description than overworking vsteel thanks ken

hello huskyman, yes, running more oil in mix is just the opposite of what all the saw manufacturer's and oil manufacturer's advise for a oil to gas ratio. the dyno tests on oil,gas ratio are from A. Graham Bell's Two Stroke Performance Tuning Book.The motor tested is suzuki rm 125c motorcross engine. the tests were run at 10,000 rpm and at oil/gas ratio's of 27-1,20-1, and 16-1. the results were as follows, 27-1 oil/gas ratio 20.3 horsepower, 20-1 oil/gas ratio 21.9 horsepower, and at 16.1 oil/gas ratio 22.1 horsepower. thats a 1.8 or 8 percent power gain
they also said at 27-1 they were beginning to see signs of piston scuffing so they didnt test at any higher oil/gas ratio's. i run all my woods saws at 30-1 and my racing saws down to 16-1 on alcohol. we use maxima 927 oil because there is no carbon build up on the piston and exhaust port . its the best oil we have found. you can get it at the motorcycle shops. its expensive but well worth it the old husky oil was very good but the new synthetic oil in the black container didn't work at 30-1 we were getting signs of heat and scuffing at the exhaust port. also when we dissassembled the engine there was no residual oil on the piston or barrel. i've still got most of the case on the shelf ken

If the saw maker recomends 50:1, and a switch to 32:1 is made, doesn't a person need to richen the top end becuse the richer mixture has a higher viscosity. I know that in the motorcycle world it is recomended that you do because it can cause the motor to lean out too much. I was just wondering if this aplies to the chainsaw world.

I want to get the longest life I can out of my saw that I can and I was also wondering if I would get better chainsaw life if I richened the carb beyond the factory settings a little. I have a stihl 029 that I have a 20 inch bar on and sometimes I really work it, (I cut up to 18 inch trees with it) and use it for getting fire wood, last week it was around 90 degrees when I was cutting wood, I was letting the saw cool half an hour after each tank of gas or the tree was finished which ever came first. (I have tuned lots and lots of 4 stroke engines and some two stroke dirt bike ones, but I have never messed with chainsaws. I would apricate any advice you can give me.)

Hello vsteel, Your correct on all questions, as you increase the oil it will lean out the mixture. Just ritchen the high speed needle until it begins to burble or four stroke and then just clean it up by turningnit back a tiny bit lean. resting your saw between tanks also really helps also cutting with a dull chain builds heat When i cut wood i use 2 saws and rotate them. If you have a newer 029 they have very restrictive mufflers there is a baffle inside them. remove the muffler and thecover and screen, drill 4or 5 holes in the baffle clean out all the chips with air or water and reinstall the cover and screen and put the muffler back on saw. you'll have about a 20 percent power increase and the saw will run much cooler kdhotsaw

You were right. I took of my screen and cover plate. wow, that saw breaths through some very tiny holes. I am going to try what you recomend. One question though, do you foul many plugs at 30:1 ratio?

Ken,

Not to be to much of a bother but perhaps would you have any advice for me? I purchased a brand new 046 Mag and up to now i have put 7 tanks full of fuel through it. I'm just wondering if you have any advice for getting the most life out of my woodland lightsaber.

Thanks
kurt vanlente aka "confused"

when it comes to women "majorly confused" but thats another forum