My rookie attempt at a little porting cleanup and matching: Compliments and ridicule welcome! :)

[RIDE-RED 350r]

OK, so I finally got around to installing the updated intake boot on my 357xp the other day. I was a little surprised to find that pulling the top end made this little job at the very least much easier, if not required all together...

So, while I had the top end off, I decided to do the base gasket delete. Then I went to GKS to get a 288 exhaust deflector to do the muffler mod.. unfortunately, my stinkin' little brother bought the last 2 he had in stock last week for his 346 and 372! Grrrr! LOL!

So, back at the garage, I decided to do a little grinding. I got it close to matching the base gasket and tapered the transfer partitions. I did not monkey with the actual cylinder port windows as I do not have the equipment or knowledge to take on that task and therefore didn't want to turn my beloved 357 into a dog.

So, top end back on and I ended up with just about .024" squish.. My friend who works at GKS told me I was good as long as it wasn't under .023"..

I took the saw out and did some cutting with it.. I really wish I could have done the muffler mod but alas, it will have to wait till Brendan gets more 288 deflectors in stock.
I have never modded a saw before, but I have to say, it sure SEEMED to run a tad stronger and faster than before. Not "holy smokes" different, but it does seem snottier. My 357 has a black coil which I am told is unlimited...

So here are some pics... fire away gents! Advice and even ridicule is welcomed! LOL!

 

[wigglesworth]

It's hard to go wrong by a muffler mod, port matching and setting squish.

Looks good from here. Lol

 

[RIDE-RED 350r]

Thank you Sir

I read another thread here that was a pretty lengthy debate about some porting on a 372xpw. I remember reading some knowledgeable members repeatedly saying "less is more" with many of the modern saws when it comes to porting... I kept that fully in mind as I was grinding...

On a side note with this saw... Recently it started to do something a little funny... After making a cut or revving it high for tuning and letting it return to idle.. it will idle good, then slowly speed up as if it were lean, then idle back down after a few seconds. It did this before and after the mods. I tried to tune it out but so far I have been unable to get it to stop all together. I'm not sure what to look at next. Initially I was thinking the old intake boot was the likely cause and it was sucking a little air.. But since the upgraded boot went on it still does it. I'll fiddle with it a little more, but for now I remain befuddled.

 

[wigglesworth]

Walbro or zama?

 

[RIDE-RED 350r]

Walbro

 

[Deleted member 83629]

 

[sunfish]

It'll run very good!

 

[wigglesworth]

Walbro or zama?

Walbro 359 carbs had some crazy problems. Some ran good some didn't. Treemonkey has a thread here on fixin em.

Zama don't flow enough without some mods.

 

[Ironworker]

Thank you Sir

I read another thread here that was a pretty lengthy debate about some porting on a 372xpw. I remember reading some knowledgeable members repeatedly saying "less is more" with many of the modern saws when it comes to porting... I kept that fully in mind as I was grinding...

On a side note with this saw... Recently it started to do something a little funny... After making a cut or revving it high for tuning and letting it return to idle.. it will idle good, then slowly speed up as if it were lean, then idle back down after a few seconds. It did this before and after the mods. I tried to tune it out but so far I have been unable to get it to stop all together. I'm not sure what to look at next. Initially I was thinking the old intake boot was the likely cause and it was sucking a little air.. But since the upgraded boot went on it still does it. I'll fiddle with it a little more, but for now I remain befuddled.

Same thing just happened on a 365 I just ported, it was also stumbling off idle when I hit the throttle, I richened up the idle and runs and idles fine. By the way nice job.
http://www.arboristsite.com/community/threads/possible-air-leak.285387/

 

[mdavlee]

Open the area under the deflector as much as possible. If you're not using screen then you can go bigger.

 

[71dart]

Seems like those auto-decomp valves have been problematic too.

 

[sunfish]

Seems like those auto-decomp valves have been problematic too.

Uh yes, I just notice it has one of those. Bad design and is only on the very early 357s'. Plug that sucker right now!

 

[RIDE-RED 350r]

Yep... after some searching around here, I have decided I will be getting the Zama carb and auto-decomp delete kit for it. I knew the auto-decomp had some issues, but mine hasn't given me any problems yet so I haven't been in a hurry to do it. The carb issue, I had no clue about till I searched the subject here.

Thanks guys.

 

[sunfish]

The auto decomp will just fry the piston pretty quick without warning is what I've heard. It could be acting up now. The Walbro carb is better than the Zama and is an easy fix, if it needs it. Look up Treemonkey Walbro 199 fix. I have walbro 199 or 191 carbs on 5-6 saws and all run fine, one is original to a 10 year old 357 and no issues.

 

[RIDE-RED 350r]

Open the area under the deflector as much as possible. If you're not using screen then you can go bigger.

Are you speaking of the original deflector or the additional deflector that will be going on when I add the extra port? Also, I was looking inside the muffler and noticed that if I were ale to add the extra exhaust port to the rear of the muffler seam that would be most beneficial for extra flow as opposed to ahead of the seam toward the front of the saw. If I can place the second port behind the seam, it will allow exhaust to exit before it is forced through the main baffle via that quarter size hole.. Only remaining question is if there will be clearance enough for the deflector mounted to the rear of the seam. I wish I could have gotten a deflector at this point... I told Brendan to let me know when more come in...

 

[mdavlee]

Yes under the original. Why not open the baffle up some as well.

 

[sunfish]

Can remove the baffle, or mount the second port behind the seam. I like to remove the baffle with a cutting torch.

 

[RIDE-RED 350r]

OK, so I've been searching the Tree Monkey fix for about an hour now and all I can seem to come up with is to send the carb to him. Can't find what the fix is and how to do it... If I need to send it to him that's fine... But I do almost all of my own wrenching on my trucks, wheelers, boats, etc... and am willing to do this too if I can..

Am I missing something here???

 

[sunfish]

OK, so I've been searching the Tree Monkey fix for about an hour now and all I can seem to come up with is to send the carb to him. Can't find what the fix is and how to do it... If I need to send it to him that's fine... But I do almost all of my own wrenching on my trucks, wheelers, boats, etc... and am willing to do this too if I can..

Am I missing something here???

Search it on youtube, he did a video.

 

[RIDE-RED 350r]

10-4.. Thanks bud.