Thank you Gypo and KD

[Mr.]

I got my 372 adjusted out today.

I used the numbers Gypo posted on the site to prove to myself that they were legit.

The MM numbers varied ever so slightly from the precentage numbers, so I used the mm numbers and ported away. Because these are the numbers most will follow. I just threw away the base gasket and used permatex anaerobic gasket maker. The same thing as loctite 518.

The saw doesn't have the compression I am looking for so I'll replace the rings, but it does hurt a stock 066.

The rpm it likes to run at is well above the factory max, but was set the same way all my saws have ever been adjusted.

Fred

 

[Freakingstang]

cool, I have the specs written down here and have them for my next project. I have too many 365 turned into 372's and 375's on the list... Got any numbers for a 385? Just picked up one of those tonight!

 

[Mr.]

Got any numbers for a 385?

Read Jenning's book. You can work from there.

The 385 is the wrong displacement for me to care about, but Simon may be able to help here.

Fred

 

[Gypo Logger]

Hi Fred, glad you're getting some good results with the figures.
The exact 385 figures I can't give out till I confirm that it's ok from my source:censored: , however, as a conservative starting point where you won't be going too far, but will see some serious power, use these figures.
Intake 158 degrees
Exhaust 163 degrees
Transfers 130 degrees
These are the figures I used on the 385 I built and I see only 5-10% less power than my 2 KD385's.
John

 

[Mr.]

Those are good conservative figures John.

Last night I found, on ebay, the grinder of my dreams. A Blue-Point right angle pencil grinder. Snapon doesn't make labelled as such, just as BP.

The number is AT1070RA

http://cgi.ebay.com/SnapOn-Blue-Poi...goryZ632QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

When I have one in my hand, I'll report on it's porting prowless.

Fred

Snap On sells them for $150 and often you can talk the salesman down.

 

[Freakingstang]

Hi Fred, glad you're getting some good results with the figures.
The exact 385 figures I can't give out till I confirm that it's ok from my source:censored: , however, as a conservative starting point where you won't be going too far, but will see some serious power, use these figures.
Intake 158 degrees
Exhaust 163 degrees
Transfers 130 degrees
These are the figures I used on the 385 I built and I see only 5-10% less power than my 2 KD385's.
John

Thanks John. Those are probably more than enough for me and my not-so-serious-non-competition firewood cutter

The question I have, is how do you effectively mark the inside of the cylinder when porting. I had a helluva time on that little 51 I am playing with. It was take small portions, remeasure, take small portions, remeasure. It got old quick.

Fred, that grinder looks nice. I like electric ones though, as in the automotive world, the air grinders require a large cfm compressor to keep them running. That grinder would be ideal for this kind of work.

Steve

 

[trimmmed]

Those are good conservative figures John.

Last night I found, on ebay, the grinder of my dreams. A Blue-Point right angle pencil grinder. Snapon doesn't make labelled as such, just as BP.

The number is AT1070RA

http://cgi.ebay.com/SnapOn-Blue-Poi...goryZ632QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

When I have one in my hand, I'll report on it's porting prowless.

Fred

Snap On sells them for $150 and often you can talk the salesman down.

Fred, is that rpm # correct as listed 75,600 RPMS????

 

[Mr.]

Yes, it is much slow than my dentist's drill, but it should be very effective.

Really, quite a bit slower.

Fred

 

[Mr.]

the air grinders require a large cfm compressor to keep them running. That grinder would be ideal for this kind of work.

Steve

It's only a small one. My compressor will keep up with a DA sander, so that pencil aint nothing.

Steve, no competition numbers have been posted. Let alone anything else that goes into a racr. I think this has been a misconception from the start. Gypo has only built WORKSAWS for the site.

This saw is my first woods port.

Fred

 

[Freakingstang]

Those are good conservative figures John.

Last night I found, on ebay, the grinder of my dreams. A Blue-Point right angle pencil grinder. Snapon doesn't make labelled as such, just as BP.

The number is AT1070RA

http://cgi.ebay.com/SnapOn-Blue-Poi...goryZ632QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

When I have one in my hand, I'll report on it's porting prowless.

Fred

Snap On sells them for $150 and often you can talk the salesman down.

I got one from my snap on guy at a repro price. It cost me just over a 100 bucks and had only been used once.

I have used it to port my 365's and 372's. Although on the smaller (under 50mm) bores it is a pain to get into the transfers where they enter into the cylinder.. I have a bunch of differant little carbides, but still can't find the right one to get into the transfers the way I would like to. other than that, it. It works great for the bottom of the transfers (crankcase side) and works well for making the right radius on the intake and exhaust ports.


-Steve.

 

[Simonizer]

I got my 372 adjusted out today.

I used the numbers Gypo posted on the site to prove to myself that they were legit.

The MM numbers varied ever so slightly from the precentage numbers, so I used the mm numbers and ported away. Because these are the numbers most will follow. I just threw away the base gasket and used permatex anaerobic gasket maker. The same thing as loctite 518.

The saw doesn't have the compression I am looking for so I'll replace the rings, but it does hurt a stock 066.

The rpm it likes to run at is well above the factory max, but was set the same way all my saws have ever been adjusted.

Fred

What color is the ignition coil? Are you running a 372 piston?

 

[Simonizer]

cool, I have the specs written down here and have them for my next project. I have too many 365 turned into 372's and 375's on the list... Got any numbers for a 385? Just picked up one of those tonight!

Take the exhaust to 54.00 mm from the 52.3mm+/- 0.1mm stock. (This is measured from the extended cylinder wall.) Bring the intake to 13.45mm from 14.8mm+/-0.1mm. Make both ports 1mm wider on each side for a total of 2mm. Throw away the base gasket. Install a 537 1622-04 Ignition module. Set the high-speed needle at 1-1/8 turns out, low speed at 1-1/8 turns out. Cut two holes on either side of the muffler to accommodate a 503-0783-01 exhaust outlet and 503-4056-01 exhaust screen. Braze them on, clean the muffler 10 times before installing it or it will end up contaminating the engine with filings, flux etc. Trim the top cover to allow for the outlet on the left-hand side of the muffler. Seal the cylinder to the crankcase with permatex Ultra-Gray, as thin as you can apply it. (Like a sheet of paper) Now you have a strong running work-saw. My 372 is a secret. Cheers buddy. Remember you are exhausting sooner and starting to intake sooner, don't get it backwards like so many seem to do.

 

[Freakingstang]

Take the exhaust to 54.00 mm from the 52.3mm+/- 0.1mm stock. (This is measured from the extended cylinder wall.) Bring the intake to 13.45mm from 14.8mm+/-0.1mm. Make both ports 1mm wider on each side for a total of 2mm. Throw away the base gasket. Install a 537 1622-04 Ignition module. Set the high-speed needle at 1-1/8 turns out, low speed at 1-1/8 turns out. Cut two holes on either side of the muffler to accommodate a 503-0783-01 exhaust outlet and 503-4056-01 exhaust screen. Braze them on, clean the muffler 10 times before installing it or it will end up contaminating the engine with filings, flux etc. Trim the top cover to allow for the outlet on the left-hand side of the muffler. Seal the cylinder to the crankcase with permatex Ultra-Gray, as thin as you can apply it. (Like a sheet of paper) Now you have a strong running work-saw. My 372 is a secret. Cheers buddy. Remember you are exhausting sooner and starting to intake sooner, don't get it backwards like so many seem to do.

Thanks for the info, but the numbers I already have are in duration and degrees. I don't work in MM numbers. I have a non rev limited coil, as all mine are older (black coils). with you figures, where it the intake and exhaust opening in degrees from TDC? I could figure it out, buy mine is back together and I am lazy. I see you didn't mention anything about transfers, why not? Who has the intake opening later and exhausting later? I haven't seen anyone that has admitted to that yet. I have tried that, and it didn't seem to make a difference either way.

I don't like running sealant as a base gasket, I machine down the cylinder to obtain a 20-24 thou clearance with the gasket installed. I also make my own muffler mods, via holes in the front with screen inbetween the hold down bracket or weld pipes onto the right side in doubble barrel shotgun fashion(without screen).

My modded 365 (specs a secret at this time)will spank a lightly modded 372. Not neccasarily these Gypo numbers, but a mild modded 372 to say the least. I will post vids once I figure out the art of square filing. Don't expect them anytime soon. lol.


-Steve

 

[046]

get one of these and simon's numbers will be a breeze...

 

[Allan.K]

I have the same one you do 046...They are nice to have..I had mine for 5 years now...

 

[Dennis Cahoon]

.....My 372 is a secret....

LMFAO!......What's the big secret? Hahahahahaha!

 

[NWCS]

Simon, i was reading a tube of the permatex ultra-grey and was wondering if you missed the statement that it is NOT fuel compatible? also taken from the permatex TDS sheet: Note: Product is not recommended for use as a cylinder
head gasket or head gasket sealant.

to me this is not acceptable for such a use. if fuel breaks the bond down you just gave the saw a major air leak risk. and that is not what your customers want at all. i have tried Permatex MotoSeal 2 with great results, but the major downfall is you must follow the directions to the letter, 24 hours drying before tightening! thats just too much time for a quick turnaround. i now use Dirko HT available through Stihl. its quick and i have never had any sealing issues with it.

 

[Freakingstang]

get one of these and simon's numbers will be a breeze...

So, just knowing mm increments from port heights makes you know what..... I use a depth gauge, while not digital, is more accurate that a set of calipers. Calipers are for measureing ID's and OD's, not depths, although there is a scale on them, I just prefer not to use them for that type of measuring.


Me, I like to understand where port openings take place. It is the port timing thing that makes all of the saw builders cringe from time to time, trying to get it right.

All I asked Simon to do was tell me where his measurements made the intake an exhaust opening occur in either total duration or in degrees from TDC. Removing 2mm from the roof doesn't tell me or you anything without the saw and cylinder in front of you to figure where the new port timing is. A duration # or a degree # from TDC will tell a little. But in all reality, 2mm is enough to the lower the compression significantly without removing material from the base of the jug. one of the 365's I built was raised about that much without lowering the cylinder and the compression loss was greater than the gain from the porting..... It needed the squish lowered to get the compression back up. But again we are taking woodsaws, not race saws.

I still find it intriguing that simon lowers the squish (not much with the stock gasket thickness) but doesn't raise the transfers to account for the change. I still think that there is plenty to be had by milling the jug down 20-30 thou....

 

[Simonizer]

Simon, i was reading a tube of the permatex ultra-grey and was wondering if you missed the statement that it is NOT fuel compatible? also taken from the permatex TDS sheet: Note: Product is not recommended for use as a cylinder
head gasket or head gasket sealant.

to me this is not acceptable for such a use. if fuel breaks the bond down you just gave the saw a major air leak risk. and that is not what your customers want at all. i have tried Permatex MotoSeal 2 with great results, but the major downfall is you must follow the directions to the letter, 24 hours drying before tightening! thats just too much time for a quick turnaround. i now use Dirko HT available through Stihl. its quick and i have never had any sealing issues with it.

I have tried several sealers, anaerobic and otherwise. This has given the best results.

 

[Simonizer]

LMFAO!......What's the big secret? Hahahahahaha!

I'll give you a hint, I will let you go from there. The wrist-pin is from an MS660. The piston is from a Jonsered and is machined, (faced) 0.050"-0.375" across the crown.