The Unlimited Dolmar 7900

[Deets066]

The 272XP coil has been used many times. But......it's far from a bolt on swap. I wanted to get one of these unlimited coils to have it copied.

It was a pain the first go round. I bet I could do one in an hour now

 

[Deets066]

 

[Mastermind]

It was a pain the first go round. I bet I could do one in an hour now

You know me Deets.......I wanna have a coil that is a bolt on swap. Something anyone could do. You, me, and a few other guys can do a 272 coil swap.......but everyone can't. I wanna fix that.

 

[Glock37]

Pics of coil mount maybe shawn can weld up a stud for it to use the 272coil


Sent from my iPad using Tapatalk

 

[Deets066]

You know me Deets.......I wanna have a coil that is a bolt on swap. Something anyone could do. You, me, and a few other guys can do a 272 coil swap.......but everyone can't. I wanna fix that.

I agree, it would be pretty sweet to have a bolt on unlimited coil with an oem timing curve.

They would definitely sell

 

[smcrow]

what modifications need to be done to a 272xp coil in order to make them work on the Dolmar? i have a 7910 that i took the baffling out and dual ported and that really woke it up but would really like to have a unlimited coil for it to really make her scream

 

[cgraham1]

Mine ran damn good with the stock coil. It didn’t hit the limiter in the cut, so I felt fine about it.

 

[Mastermind]

what modifications need to be done to a 272xp coil in order to make them work on the Dolmar? i have a 7910 that i took the baffling out and dual ported and that really woke it up but would really like to have a unlimited coil for it to really make her scream

That saw is RPM limited to 12,800 I believe. Honestly, unless it will hold more RPM than that in the cut, there is no real advantage to having an unlimited coil.

A 6400 - 6421 has a coil that is limited to 13,500.....surely it will never surpass that under load?

What I want these coils for is race saws and highly modified saws.

 

[cgraham1]

what modifications need to be done to a 272xp coil in order to make them work on the Dolmar? i have a 7910 that i took the baffling out and dual ported and that really woke it up but would really like to have a unlimited coil for it to really make her scream

An unlimited coil won’t change how the saw runs in the cut, unless the saw is ported to the point that it is still wanting to four-stroke in the cut above the 12,800 rpm limiter. Honestly it’s just a waste of time.

 

[TreeLife]

A bolt on unlimited coil would be excellent for a race application. Also be cool for guys that aren't pros at tuning limited coil saws.

 

[Deets066]

An unlimited coil won’t change how the saw runs in the cut, unless the saw is ported to the point that it is still wanting to four-stroke in the cut above the 12,800 rpm limiter. Honestly it’s just a waste of time.

The dolmars are at the top of the cc bracket in the race classes. Great saws and make lots of power, but you have to be a helleva operator and have a damn good chain to surpass someone who is hitting the cant 4,000 rpm more than you.

 

[cgraham1]

The dolmars are at the top of the cc bracket in the race classes. Great saws and make lots of power, but you have to be a helleva operator and have a damn good chain to surpass someone who is hitting the cant 4,000 rpm more than you.

I just cut firewood... I was replying to the guy who just has a muffler mod, not to the guys racing saws.

 

[Deets066]

I just cut firewood... I was replying to the guy who just has a muffler mod, not to the guys racing saws.

Yeah, for just firewooding the stock coil is what you want.

 

[cus_deluxe]

i wonder, is there a difference between the timing curve of the 272 coil vs say a 55 coil. They appear to share the same part #? Also, some guy in ohio has a pretty *b-wordin 5 cube pull-on with a factory limited coil, and it runs pretty well...

 

[Deets066]

@Hedgerow runs the Mutt with a limited coil. Have fun beatin him.

But there again, operator and chain...

 

[Deets066]

Oh, and a saw ported by @mdavlee

 

[dustinwilt68]

These would definitely sell, probably to a lot of firewood guys who want all they can get out of there saw too, mine is limited to 13,000 and I want be touching it, but there are plenty who would. I can completely understand it for the race application saws, where rpm is more important on a 12" cut the running a 28" bar in a log.

 

[166]

Anybody near Newport News VA? That's the last spot that coil was known to exist.

 

[smcrow]

That saw is RPM limited to 12,800 I believe. Honestly, unless it will hold more RPM than that in the cut, there is no real advantage to having an unlimited coil.

A 6400 - 6421 has a coil that is limited to 13,500.....surely it will never surpass that under load?

What I want these coils for is race saws and highly modified saws.

so i would be better off getting a 6400-6421 coil for mine just for the added rpms. like you said i doubt i am getting over the 12,800 rpms in the wood but would be nice to know that i could go higher....lol...

 

[Redfin]

It was a pain the first go round. I bet I could do one in an hour now

Wanna race?

what modifications need to be done to a 272xp coil in order to make them work on the Dolmar? i have a 7910 that i took the baffling out and dual ported and that really woke it up but would really like to have a unlimited coil for it to really make her scream

Mount mods, longer lead, timing light (at least for me) to verify.