Project Stumpbroke Dolmar 5105

[Stumpys Customs]

I'm gonna do some catching up on some builds I've done. This lil dollie was done a couple of weeks ago. I figured I'd show what I come up with only using all that Dolmar gave me to work with.

This saw is almost brand new.

Here's the stock vid. Well, not completely stock. It already had the muffler opened up on it.
[video=youtube;1i1mBPMVsKA]http://www.youtube.com/watch?v=1i1mBPMVsKA&feature=share&list=UL1i1mBPMVsKA[/video]

 

[Stumpys Customs]

Some pics with the cover off

All down to the case

 

[ancy]

What are you going to do to it?

Sent from my XT881

 

[Stumpys Customs]

Now down to the fun part.

Squishband & base cut

All laid out & ready to port

 

[Jimmy in NC]

opcorn:

 

[Stumpys Customs]

What are you going to do to it?

Sent from my XT881

It's already been done.:msp_wink: I delivered it @ the Jasper AR GTG a couple of weeks ago.

My goal with this one was to use only the stock parts. I've heard & figured out that a Husky piston works real nice in these, but the bigger challenge seemed to be getting fair gains out of them with the factory slug.

 

[XSKIER]

opcorn:

Yep...

Who needs a 70cc anyway?

 

[Stumpys Customs]

Here's the cyl all ready to go.

 

[Stumpys Customs]

On to the muffler.

Here's what the muffler already had done to it.

Time to let the cat out.

 

[Jimmy in NC]

You're wasting no time getting the most out of the new high speed connection are you?

Nice work as always!

 

[Stumpys Customs]

ALl back together & ready to go. I also built a 7900 for the same customer.
A nice pair of saws.

ANd here is what the after vid looks like.
[video=youtube;oFGe4k_07Sw]http://www.youtube.com/watch?v=oFGe4k_07Sw&feature=share&list=ULoFGe4k_07Sw[/video]

I think there is a vid of it raceing heads up against a ported 346 in the GTG thread.

 

[Stumpys Customs]

Here's the stock vid fore that 7900.
[video=youtube_share;ogorPQEfQzU]http://youtu.be/ogorPQEfQzU[/video]

 

[Stumpys Customs]

And the finished vid of the 7900
[video=youtube;HgICau4zEqg]http://www.youtube.com/watch?v=HgICau4zEqg&feature=share&list=ULHgICau4zEqg[/video]

 

[Stumpys Customs]

You're wasting no time getting the most out of the new high speed connection are you?

Nice work as always!

The upgrade is much faster. It used to take 45min to upload a 50sec vid. Now it only takes 5 min.

The timing numbers. (durations)

Stock
ex 140
tr 100
in 142
Squish .030"

ported
ex 144
tr 108
in 166
Squish .024"

 

[Hedgerow]

If I'm not mistaken, that 5105 of Heavyfuel's edged out the ported 346 of Andy's in cant racing... I do remember it being real close...

 

[chainsawnut460]

Nice work stumpy, who'd a ever thought a 5105 could ever dethrone the legendary 346

 

[HEAVY FUEL]

If I'm not mistaken, that 5105 of Heavyfuel's edged out the ported 346 of Andy's in cant racing... I do remember it being NOT real close...

Fixed it for ya..

 

[Brian VT]

Did you check the compression before and after ? Would it now benefit from higher octane ?
Did you play with the ignition timing ?

(Stock)
Squish .030"

(Improved)
Squish .024"

 

[Hedgerow]

Fixed it for ya..

As a Dolmar fan, I was trying not to rub it in...
Hahaha!!!:msp_wink:

 

[Stumpys Customs]

Did you check the compression before and after ? Would it now benefit from higher octane ?
Did you play with the ignition timing ?

The comp was @ 165psi stock. I didn't get a reading after. Maybee Heavy Fuel could take a reading & let us know.

It may or may not like more octane. I don't want this to turn into another fuel thread. All I'll say about that is with any saw, make test cuts to see what fuel it likes best. Remember to retune for each fuel.

I did advance the IGN timing 4 degree's over stock.