Porting A 346XP With Aftermarket Top End

[Mastermind]

Everyone looks at the Chinese top ends with scorn, myself included. I wanted to treat this one to the same treatment that I would any other, so here goes. This saw belongs to Tbone (John) BTW.

I shaved .035 from the base and made a .035 popup. The squish band is perfect, it ended up with .018 in all four spots I checked it it. Nothing wrong with that. This picture is of the jug before any porting has been done, just the machine work.

Here's a few of the "implements of destruction" I used on the jug.

The as cast numbers on this jug are a bit less than that of a stock 346 IIRR.

Intake duration: 148° = 74° FTDC
Exhaust duration 144° = 108° FTDC
Transfers 129° FTDC = 21° BD

I didn't take many pics, but I wanted to show the plating around the ports and at the top of the bore. These transfer ports turned out good after widening and raising them 3 degrees. I'm liking these right angle handpieces.

In these next two shots you can see the strange casting marks in the squish band. I thought at first they hung down a bit into the chamber, but after checking the band by smashing solder against it I can't detect any differences.

 

[logging22]

I would love some of those right angle thingys. Really nice work. Im a fan.

 

[ale]

Looks killer! You have more crazy tools than my dentist.

 

[Mastermind]

I'll get it together tomorrow and make a video. I think it will run fine.

Oh yeah, the finished numbers.

Intake duration: 154° = 77° FTDC
Exhaust duration: 156° = 102° FTDC
Transfers: 126° = 24° BD

Here's a couple of shots that wouldn't fit in the first post.

 

[Mastermind]

I would love some of those right angle thingys. Really nice work. Im a fan.

Yeah Les, but who wants a ported saw anyway???

Looks killer! You have more crazy tools than my dentist.

Those are dental tools.

 

[sunfish]

Nice work, man!

I'm interested to see how this one stacks up against an OEM P&C...

 

[logging22]

Yeah Les, but who wants a ported saw anyway???



Those are dental tools.

Ported saw? Im in the wrong thread, i thought you said porterhouse. My bad.

 

[FrichKazzone]

I would love some of those right angle thingys

 

[Ductape]

Those are dental tools.

Those are the tools of a sadist !! :msp_ohmy:

 

[blsnelling]

Looks great Randy. I've got one of those cylinders here I plan to do some experimenting on.

 

[Mastermind]

Looks great Randy. I've got one of those cylinders here I plan to do some experimenting on.

It's impossible to tell just by looking at it but in all honesty I can't see any reason why it shouldn't run well.

 

[blsnelling]

And yes, I'm jealous of those right angle pieces

 

[Mastermind]

And yes, I'm jealous of those right angle pieces

I'm still working on adapters to fit them to the Foredom but they work well. :msp_thumbup:

 

[parrisw]

Nice Randy! Those dental hand pieces are great, that's what I use. I have the Contra Angle piece. I don't know how anyone works over uppers without them?

 

[wigglesworth]

Looking good Randy. Im really diggin them transfers.


Sure wish I had me one of them angled hand pieces.

 

[parrisw]

Looking good Randy. Im really diggin them transfers.


Sure wish I had me one of them angled hand pieces.

They really are great. Al was the one that put me on to them. Got it off Ebay for not too much $$$

 

[Arrowhead]

Lookin good Randy.

By the way, I need to cancel my 2:30 root canal.

 

[Mastermind]

Looking good Randy. Im really diggin them transfers.


Sure wish I had me one of them angled hand pieces.

I got one for ya Bro. Brand spankin new.......still in the sterile wrapper. :msp_wink:

 

[mayhem100]

Looking forward to how this works out. I've got a 346XP OE that got straight gassed with a chinese 50cc top end on my bench. I've got a couple tanks through it and have no issues as far as I can tell, though for all I know its a 353 50cc top end and not a 346 50cc...I probably ought to check that out. Saw rips, but can't keep up with my 359 which makes me suspicous.

Seller put the top end in so I don't have any purchase history. Anyone have any thoughts? Tempting to send it to someone to port it over the winter and see what it can do. Ditto the 359 of course.

 

[sunfish]

Looking forward to how this works out. I've got a 346XP OE that got straight gassed with a chinese 50cc top end on my bench. I've got a couple tanks through it and have no issues as far as I can tell, though for all I know its a 353 50cc top end and not a 346 50cc...I probably ought to check that out. Saw rips, but can't keep up with my 359 which makes me suspicous.

Seller put the top end in so I don't have any purchase history. Anyone have any thoughts? Tempting to send it to someone to port it over the winter and see what it can do. Ditto the 359 of course.

I'd be puttin a real 346 top end on it, or have it ported. It should give the 359 a fit... :msp_biggrin: