Building a 390XP Monster

[jropo]

Um, ya them saws sound nasty! I want one. Need one? No. Want one? YES!
What were they wearing?

Looks like you guys had fun!

 

[parrisw]

How does the porting line up with each saw?

 

[blsnelling]

What were they wearing?

32" RSC on the 2188 and 36" RSC on the 390XP. Both were wearing 7-pin rims. I like torque in a worksaw.

 

[blsnelling]

How does the porting line up with each saw?

390XP
Exhaust - 97
Transfers - 114/118 staggered
Intake - 84
Blowdown - 17/21
Compression - 190-200 can't remember for sure
Timing advanced 6°
Carb bored 1mm

2188
Exhaust - 100
Transfers - 119/121 staggered
Intake - 95
Blowdown - 19/21
Compression - 198
Timing advanced 6°
Carb stock

 

[parrisw]

390XP
Exhaust - 97
Transfers - 114/118 staggered
Intake - 84
Blowdown - 17/21
Compression - 190-200 can't remember for sure
Timing advanced 6°
Carb bored 1mm

2188
Exhaust - 100
Transfers - 119/121 staggered
Intake - 95
Blowdown - 19/21
Compression - 198
Timing advanced 6°
Carb stock

Cool. How do you stagger your transfers? Intake one higher? Like is one trans higher then the other? Or do they slope up from ex to intake? Or vise versa?

 

[OhioGregg]

For what its worth. As a inexperienced ported saw runner, I had the opportunity to run both saws also. I ran them a little earlier in the day. I thought the Husky had the edge. Talking to Nik, he thought the same thing, but others thought the opposite. LOL And I think the stop watch gave the edge to the 2188. Either way..they are darn close, and both a hoot!


Gregg,

 

[blsnelling]

Cool. How do you stagger your transfers? Intake one higher? Like is one trans higher then the other? Or do they slope up from ex to intake? Or vise versa?

One's just higher than the other, not sloped. Actually, I have the exhaust side one's opening up first. That's not the norm, but something another builder suggested trying. It certainly doesn't hurt!

 

[parrisw]

One's just higher than the other, not sloped. Actually, I have the exhaust side one's opening up first. That's not the norm, but something another builder suggested trying. It certainly doesn't hurt!

I've never tried it. I've always thought that you'd want the intake side to open last.

 

[Officer's Match]

Looks like a great time. I would have loved to have been there to give my 390 a go, but my daughter was back from college for her birthday.

 

[blsnelling]

I've always thought that you'd want the intake side to open last.

Me too.

 

[ChipMonger]

Both saws scream Brad, nice work. What wood were you cutting, Oak? looks like it to me.

 

[Andyshine77]

I also liked the 390 better than the 2188, but I guess the 2188 had a little more grunt, and after looking at Brad's numbers I can see why. Sure the larger bore may have played a role, but the numbers did the trick IMHO.:msp_smile:

 

[Mastermind]

I also liked the 390 better than the 2188, but I guess the 2188 had a little more grunt, and after looking at Brad's numbers I can see why. Sure the larger bore may have played a role, but the numbers did the trick IMHO.:msp_smile:

You must subscribe to the "less can be more" thinking as well.

 

[greg409]

Loved the video, in spite of what everyone else says, it was blatantly obvious that the Jonsereds was far superior.

This in spite of the fact you tamed it with a 7t sprocket, but that's OK, I like Huskys next, then Partner, then Homelites.

Nice saws, nice videos,

Thank you Brad,


luck,greg

 

[blsnelling]

I used my lathe and bored out two Tilly HS carbs tonight, one for each of these saws. I'll be bolting them on to see if they still work later in the week.

 

[blsnelling]

You must subscribe to the "less can be more" thinking as well.

These saws are so close it's not funny. It depends on the wood which one will come out on top.

 

[Mastermind]

These saws are so close it's not funny. It depends on the wood which one will come out on top.

They both look strong.....

 

[blsnelling]

I tried to determine a clear cut winner, and couldn't do it. They just have slightly different "personalities". I think I'm going to leave the pipe and 2-piece head setup at home, and leave both of these setup like they are, only adding the "new" carbs to both of them. I'd like to get more time behind them, as well as some more of you guys opinions. I have a lot of testing and tuning yet to do to the pipe, and don't plan on having that done by then.

 

[parrisw]

I tried to determine a clear cut winner, and couldn't do it. They just have slightly different "personalities". I think I'm going to leave the pipe and 2-piece head setup at home, and leave both of these setup like they are, only adding the "new" carbs to both of them. I'd like to get more time behind them, as well as some more of you guys opinions. I have a lot of testing and tuning yet to do to the pipe, and don't plan on having that done by then.

I'd say there should be at least a dozen tanks through both then retest.

 

[Mastermind]

I tried to determine a clear cut winner, and couldn't do it. They just have slightly different "personalities". I think I'm going to leave the pipe and 2-piece head setup at home, and leave both of these setup like they are, only adding the "new" carbs to both of them. I'd like to get more time behind them, as well as some more of you guys opinions. I have a lot of testing and tuning yet to do to the pipe, and don't plan on having that done by then.

I'm not sure I'll have anything done for the cant racing. I'll have several work saws though. We shall play.