Well I put some time in today on the cylinder that CurtisR401 sent me.
I will call this Engine the R401 experimental.

Plans for this Engine:
1) Cut fins off cylinder and liquid cool like I did to the other engines
2) Use the 82mm welded piston: viewtopic.php?f=1&t=17519
3) Use NO head gasket
4) Make a cylinder head from scratch out of a piece of 6" aluminum round stock

Had one set back already. The ring I rolled was to tight. It was 6" alright but I forgot about some clearance. Rolled another one.

Very excited to see how this goes, amazing pics as always

Question: In the pic below you can see I drew some lines inside the cylinder with a pencil. I want to square up the exhaust port based on those lines you see there. I am not a pro in doing port work. Does anyone see anything wrong with what I want to do there ??

You never cease to amaze me. Awesome project.

Clean the top of the fin at the bottom of the ring before you weld.

Looking good.

Are you going to port out (remove) the exhaust bridge or are you just porting deeper into the corners?
I wouldn't know the difference but im curious to your plans, awesome project brother cant wait to see how this turns out

You can NOT remove the exhaust bridge on an FL350.
If you do the rings will snag the port.
I am just going to go deeper into the corners and square them out a bit but I am not sure yet because no one has commented on my question.

I commented on it :> haha. But yeah i thought i read that before, and if you made the bridge thinner it would get hotter faster, right? Right. Tis why i was curious about your plans, being the innovator you are.

Anybody got any comments for me on cutting those exhaust ports square ??
I don't want to F up this cylinder.

Are you saying you want to make the ports exactly square? I wouldn't. I read somewhere that you want to keep a radius at the corners of all ports except the boost port. The less radius the higher the risk. A square port would also be turbulent compared to a rounded port.

I'm a square head so I thought square would be good -- I am.
Maybe I should just leave it.
Lots of experimental on this thing and I don't want to ruin a jug on it's last bore.
Since it has a welded piston in it, I would want to know if it was the piston that caused any catastrophic failure, and not a mickey mouse port job.
Did a bunch of welding on the cylinder already. Will finish it tomorrow and post pics.

Since you are thinking of port experimentation, why not take a port map from something like a race Engine and map it onto the jug? Honestly I see a lot of wrong in this thread, but, if you race port the thing and it pulls like a bat out of hell then more power to you! I like experiments especially if everything is 'junk' to begin with. No harm no foul.

Just don't get cocky and think you can sell this beat Engine off to some sucker. That is where I would draw the line.

WOW -- It's amazing to read some of the thoughts in other people's minds.
That never even entered my thought process .
I guess the world is full of scammers and gangsters so that would be a legitimate belief.
I never sell ANY of my oddy stuff. I only buy and collect.

It's looking good CO!

This is as far as I got the other day and just to sore from walking to do anything today.

Had this pic on my computer and forgot about it until now.
It's a pre-recall FL350 cylinder.

Edit: here is the thread I got it from -- viewtopic.php?f=4&t=17410
Methodical was selling it last year.

that's interesting, makes you wonder why they opted to change it for the post-recall cylinders?

Basically that port work is what I was trying to copy.
Not really sure what I'm going to do yet with regards to the exhaust porting.
Just waiting for my legs to stop hurting from that walk out of the bush the other day. Then I will get back on this project.

Following this one, looks pretty cool so far.

Finished welding up the liquid cooling sleeve on the cylinder and pressure tested it.
Found several leaks just like on all the others. Welded them up, retest, good to go.
Cut the bridge out of the intake like everyone else does. Not sure why they even put that in there.
Did a wee bit of port work on the intake but left the exhaust alone. Not sure what I am going to do on those exhaust ports yet. I am leaning toward leaving them alone.
Still waiting for that sparkplug tap to come in the mail. Unfortunately the postal service is on rotating strikes here. They have been without a contract for a year now. Company pleading poverty like always but the big shots make ten times what the average guy makes. Same old story everywhere. So when the taps show up I can start on making the liquid cooled head.

I tried to fit some things together tonight but the wrist pin would not go through the piston.
Had to use my new top quality Chinese adjustable reamer to clean out the wrist pin bore.
This may be a result of the welding I did on that piston or it could be from the blown up Engine this piston came out of. You will find that you can not push the wrist pin out of a wiseco piston very easily after a poofkaboom. I bet money those pistons distorts some.
If you look close at the piston pic you can see the skid marks from the reamer.

The port design on the second cylinder might have more material in areas that the one you have doesn't? Could be risky trying to make it the same shape? Only thing I thought of when I seen it, was to keep the corners radius as possible to help keep it from cracking. But I really don't know anything about porting a 2 stroke..lol

Do you plan on lapping the cylinder head deck after welding? Might not be a bad idea just to confirm it is true.

fine sand paper on a piece of glass should work.

Nice work like always!

I have done 4 engines this way now and this is the 5th. So far I have not had any issues with head gaskets because of any warpage. I think this is due to the fact that I only weld a very short distance and stop for a while to let the aluminum cool. If you try to do this in one shot the aluminum just washes away because of the heat. I have all metal tables in the shop, so may be I will just lay some sand paper on the table and slide this cylinder on it, just to verify what you are saying. I already laid a straight edge across it and it looks good. The skid marks from the sand paper will verify it for me so I will give it a go this time.



I looked at the cylinder good and it looks like there is enough meat in the areas I wanted to hog out.
The thing is that I want to see if you can use a welded piston and that is what all of this is about in the first place. If the Engine grenades I want to verify it was a piston failure and not a mickey mouse port job failure that caused it. Secondly I want to see if you can make a head out of aluminum round stock you get at a machine shop and if it will hold up. The stuff Honda uses to make the cylinders and heads are some kind of aluminum pig iron alloy. It's hard to weld and very porous.

I would imagine some quality billet aluminum would be perfect for the job.