Porting Stihl 038 - The intake hump???

[Brewz]

Yeah the transfers are huge so was just looking to do a bit of smoothing and directional work. Nothing major.

I am liking saws with a lower exhaust at the moment. My 10mm 044 is running 105 and it is bordering on scary. leans out at about 15500 rpm and runs great at 15000 rpm
I'm now regretting raising my 064 exhaust to 102.5 but have another jug

 

[DSS]

I've built some 038 Mag IIs that will make a feller pretty happy. With the stock carb and boot.....

Yeah, mine will make your pecker stick out. Still works perfect and I've used it a lot.

 

[Mastermind]

Yeah, mine will make your pecker stick out. Still works perfect and I've used it a lot.

I'm calling BS.

We all know there ain't nothing in Greenland but frozen tundra...

 

[Brewz]

And how skinny are his legs?

 

[Mastermind]

And how skinny are his legs?

He was once known as Widebody on AS. So.....

 

[DSS]

bahahaha fat bastards

 

[Fifelaker]

Discuss.

 

[Mastermind]

Yeah......that's Chris.

 

[Duane(Pa)]

Sticker peck out?

A little...

 

[Big_6]

If your going that far, sell it and get an 044.
I am not interested in extreme porting these 038's, just a bit of flow and directional work to help them along

Just dual or tri port the muffler!
Adv the timing too!

 

[Brewz]

102.5/122/70 stock with gasket and .038 squish

Nice!

 

[Brewz]

104.5/124/71.5 with gasket delete.

Going to run it with no gasket and take the timing to 104/123/74

 

[Al Smith]

If I were going to port an 038 mag I'd raise the exhaust by one degree and modify the intake to match an 066 or 372oe intake boot. A carb upgrade may not be necessary. I wouldn't touch the transfers since they're already larger than a slant fin 044.

It's all a matter of preference .One of my 038 Mags is set at 96 after .Lowers were widened,uppers were swept back ,pop up . 4 stroking at 14,500 RPM stock Bing carb .It will hang with a stock 660 in big stuff .Comp is high enough it wears a d-handle .---Keep in mind it took me 4 times of going into that engine to get it that way .

 

[Brewz]

Ended up with 103/124/73
Squish is .019

That'll do donkey.... that'll do!

 

[drf256]

I'd give it more intake Tony.

 

[Al Smith]

I did an 038 AV slightly different .An AV has a hemi domed piston and an offset chamber .So nothing done to the piston ,lowered the cylinder some which took it from 101 or there abouts to about 104 .Raised it to 99 .Hogged out the intake,work on the lowers none on the uppers .

It was an improvement .Took it up to just about what my stock 038 mag is .Then again it's one of the saws that gets very little run time of which I have several .Tweek them,massage them,damn near make love to them and then almost never use them .Such is the life of a gear head .

 

[Brewz]

I thought about it.
I kept it a tad higher due to the shorter stroke. I figured that it has the same bore diameter as an 064 but (I think) 6mm less stroke.
That means less physical travel per degree of rotation.

I was worried if I took it down to 76 or 77 case compression would suffer due to the shorter distance traveled after the intake closes.

Thoughts?

 

[Brewz]

I also shrunk the thing in the top the intake so it still acts as a support for the ring

 

[Mastermind]

I like it Tony.

 

[Brewz]

I like it Tony.

This one will be a work saw so I don't want to hang the ring,

What's your opinion on the intake height?