Another chainsaw dyno...

[MustangMike]

I think DEET's Hybrid is the best example of what good porting can do, and Joe's hybrids are not far behind!

I can remember when several of the porters did not even want to do a Hybrid, and it may still be true!

 

[rogue60]

Talk is cheap the dyno doesn't lie lol

 

[jacob j.]

I think DEET's Hybrid is the best example of what good porting can do, and Joe's hybrids are not far behind!

I can remember when several of the porters did not even want to do a Hybrid, and it may still be true!

I built my first one back in 2002, when most guys on this forum were still running Wild Things and Timber Bears...

I’d like to see a Wiggs ported 372 on there. Would Probly put a lot of 90cc saws to shame.

Word on the street is that Jeremy builds a strong motor...

 

[Redfin]

Good stuff JJ. Good stuff.

 

[Redfin]

Theoretically 4hp @ 15.5k should cut about twice as fast as a stock 60cc @8000rpm as long as wood cutting physics don't have a problem with that kind of chain speed.

Quit trying to wrap your head around hp. That is only part of the equation vrs time.

Perfect example of this is how low both the 500i and 462 built max torque.

The key is building these saws is to extend even those same torque numbers to a higher range in rpm.

Good stuff here. Thanks Joe.

 

[MustangMike]

It is very impressive how much more power the 572 had than the 046 (both stock). If they are all like that, a lot of owners will be very happy.

Will be interesting to see how much more can be had from porting.

I know 460s generally wake up nicely.

 

[ranchdadmike]

Road trip?

I do have a 15 passenger van..

 

[Deets066]

Word on the street is that Jeremy builds a strong motor...

JAKE is a beast. Would like to see it’s graph. I know it’s above my hybrid.
@Hedgerow

 

[Red97]

I do have a 15 passenger van..

Pick up people/saws on the way up.

 

[Nutball]

Quit trying to wrap your head around hp. That is only part of the equation vrs time.

Perfect example of this is how low both the 500i and 462 built max torque.

The key is building these saws is to extend even those same torque numbers to a higher range in rpm.

Good stuff here. Thanks Joe.

As I said earlier, I had a brain fart and didn't give thought to the torque/rpm relation. Building a saw to have more torque at higher rpm just = more HP, the obvious goal being having max power, more specifically torque, at the intended working rpm.

I was talking about how to use the HP at really high rpm, but that would require different gearing, and wouldn't cut faster.

 

[ranchdadmike]

Pick up people/saws on the way up.

We usually roll with the 10 of us and all our luggage (8girls) so I think I’d have room for lots of folks and saws...could be a big dyno party


Who’s in for a road trip? [emoji604]

 

[mdavlee]

JAKE is a beast. Would like to see it’s graph. I know it’s above my hybrid.
@Hedgerow

It might be a 11 hp 71cc saw

 

[Terry Syd]

Other than maybe limbing i don't see any of the over rev power being super useful.

Extra speed during limbing was my initial thoughts about having the air bleed on the main jet. However, the engine would rev like crazy without a load. I decided that an increasingly rich fuel mixture from a fixed main jet was a better option. Max power was achieved and then the power would drop off faster after the peak and thus provided a safety measure to the engine.

I could see that an air bleed on the main would be a great idea for a KART engine going down the back straight where you would want it to wind its' guts out, but on a work saw it just wasn't necessary.

If the factory wanted to extend the powerband for faster limbing it could go to the extra expense to have an air bleed on the main (it requires an extra valve in the high speed circuit, plus another jet), but it would also require a rev limiter on the ignition. Otherwise, I could see all sorts of problems with people blowing up their engines from over revving the engine.

 

[TreeLife]

It is very impressive how much more power the 572 had than the 046 (both stock). If they are all like that, a lot of owners will be very happy.

Will be interesting to see how much more can be had from porting.

I know 460s generally wake up nicely.

I feel like there probably isnt as much left in the newest generation of saws as compared to a older machine like a 046. There comes a point where only so much volumetric efficiency and energy can come from a given engine size before adding positive intake pressure.

 

[Red97]

20cc 2511t 1.2hp
30cc
40cc
50cc mms 5105 5.6hp
60cc mofo 036 7.3 hp
70cc deets 044 hybrid 10.2 hp
80cc 86cc echo hybrid 8.6hp
90cc 661 stroker 12.5hp
100+cc 3120 practice saw 13.4hp


Leader board

 

[Duane(Pa)]

My thoughts are that rev limiter coils came about after lean melting engines in the quest for low emissions.

 

[Armbru84]

20cc 2511t 1.2hp
30cc
40cc
50cc mms 5105 5.6hp
60cc mofo 036 7.3 hp
70cc deets 044 hybrid 10.2 hp
80cc 86cc echo hybrid 8.6hp
90cc 661 stroker 12.5hp
100+cc 3120 practice saw 13.4hp


Leader board

Forgot the unlimited class...

 

[Deets066]

20cc 2511t 1.2hp
30cc
40cc
50cc mms 5105 5.6hp
60cc mofo 036 7.3 hp
70cc deets 044 hybrid 10.2 hp
80cc 86cc echo hybrid 8.6hp
90cc 661 stroker 12.5hp
100+cc 3120 practice saw 13.4hp


Leader board

The 1.2hp 20cc cracks me up. Lol

 

[Red97]

Forgot the unlimited class...

Well I don't think any more unlimited will get to make a hit...

 

[Red97]

The 1.2hp 20cc cracks me up. Lol

Well that was a stock run, maybe it will be a fire breathing monster later this afternoon...