Stihl 026 muffler gasket question

[Todd Noel]

Hi guys!
This is my first post. I have my late dad's Stihl 026 that I wanted to play with a little. I bought the saw for him in '96. The Piston, rings and cylinder were fine but I decided to install an MS260 (big bore) kit. I ordered a Hyway cylinder kit and Caber rings. Quality appears to be good-just did some minor clean up with a Dremel.
Question is the kit came with multiple exhaust gaskets including one that looks like a heat shield. Do I need this with the small increase in displacement or just use the simple gasket that matches the original? I suspect the later 026's and MS260's run hotter with their baffled mufflers. Mine is open inside and I'm installing an Egan Straight Shot cover plate as well.
I may have answered my own question here but wanted to introduce myself to the community.
Thanks for any thoughts you may have!

 

[ballisticdoughnut]

I would install the heat shield. Shield goes on first, no gasket. Gasket goes between shield and muffler.

 

[Todd Noel]

I would install the heat shield. Shield goes on first, no gasket. Gasket goes between shield and muffler.

I was thinking it might help channel airflow past the cylinder for better cooling. Not just a heat shield? Thanks for the advice.

 

[Mad Professor]

Do the Highway kits show any increase in power over the OEM P/C?

 

[ballisticdoughnut]

I was thinking it might help channel airflow past the cylinder for better cooling. Not just a heat shield? Thanks for the advice.

Short answer, yes. The “heat shield” is really more of an air guide.

 

[thompsoncustom]

Do the Highway kits show any increase in power over the OEM P/C?

No and actually the older 44mm OEM cylinder make more power than the newer 44.7mm OEM (big bore) ones most of the time.

 

[Todd Noel]

Do the Highway kits show any increase in power over the OEM P/C

Do the Highway kits show any increase in power over the OEM P/C?

I really couldn't tell ya. I haven't put it all back together. What I do believe is the craftsmanship of the Taiwanese (Hyway) cylinder and piston looks pretty darn good. The transfers, intake and exhaust ports were cast well and they left very little to clean up. I just smoothed thing out and removed a few small casting dingleberries. Port shapes and sizes are very similar to the stock cylinder. Not checking timing but will check squish band clearance on assembly. Just for info the cylinder base gasket with this kit measures 0.5mm thick. Same as my original gasket.

 

[thompsoncustom]

I really couldn't tell ya. I haven't put it all back together. What I do believe is the craftsmanship of the Taiwanese (Hyway) cylinder and piston looks pretty darn good. The transfers, intake and exhaust ports were cast well and they left very little to clean up. I just smoothed thing out and removed a few small casting dingleberries. Port shapes and sizes are very similar to the stock cylinder. Not checking timing but will check squish band clearance on assembly. Just for info the cylinder base gasket with this kit measures 0.5mm thick. Same as my original gasket.

You should check timing. Not sure on the hyway but aftermarket 260 cylinder tend to have exhaust ports on the low side number wise and higher physically, intake and transfer ports tend to be pretty good timing wise but the upper transfer do tend to lack shape.