Another chainsaw dyno...

[Red97]

Pickup you say?View attachment 248678

Well.... Prolly still a diff curve than an equivalent hp powerstroke/duramax...

 

[Fifelaker]

I've posted a 3120. Close to 4hp more and 3ftlb more than these hybrids

Not done any 394, or husky stroker.

The 661 stroker was +2hp and almost +2 ftlb over these hybrids.

The 395 that was the same hp, had about 1 ftlb more tq than these hybrids.

700 hp Indy car vs 700 hp pickup diesel

Soon sir.

 

[TreeLife]

@Red97 why dont you tell us what models you are looking to dyno and catalog so we can help. Unfortunately I dont own any stock saws, but I'm sure our fellow members do as well as ported ones

 

[Deets066]

I don't know much at all about carbs, but I will tell you that I have a CFB Hybrid, and we tried several carbs on it but could not get it to 4 stroke till we put one with a 70 jet on it (I believe it is a HD-14 if memory serves me right … the NLA ones for the heated handle saws).

Now I'm just guessing … and I've been known to be wrong with some of my guesses … but if I had to guess the Hp of my Hybrid I would say close to 8 +/-.

DEET's comments on the transfers is very intriguing. I think most folks tried to increase "case capacity" on the Hybrids, to be more like a 460, but he seems to have gone in the other direction. Very fascinating!

But both saws have carbs modified to increase flow … that says something right there. My carb is all stock.

I guess the thing I'm pondering now is do higher RPMs require less of a venture to pull the correct amount of fuel, or said another way, will a stock venture get "too rich" with higher PRMs and cut the performance short?

The whole point of building a hybrid is to increase velocity. Why increase volume to match a 460? If that was the case, just port a 460.

 

[Bigmac]

The whole point of building a hybrid is to increase velocity. Why increase volume to match a 460? If that was the case, just port a 460.

Ya and lighter weight, the stuffed case helps revs to0

 

[Redfin]

Well.... Prolly still a diff curve than an equivalent hp powerstroke/duramax...

Dammit Man, do you just wanna argue and fark up another thread?

Or this just an innocent derail until you get your part?

 

[Red97]

Dammit Man, do you just wanna argue and fark up another thread?

Or this just an innocent derail until you get your part?

But what about a equivalent hp gasser...

 

[Bigmac]

But what about a equivalent hp gasser...

What about power to weight?

 

[p61 western]

But what about a equivalent hp gasser...

Pics lol

 

[Bigmac]

Pics lol

That’s the HP of a street big block nowadays...

 

[Redfin]

But what about a equivalent hp gasser...

We talkin bout the hp of the nova or just one you can order out of JCWhitney?

 

[p61 western]

That’s the HP of a street big block nowadays...

Working on supporting mods right now.

 

[Red97]

We talkin bout the hp of the nova or just one you can order out of JCWhitney?

They still around? JCWhitney?

I'm just talking hp/tq curves

1500hp is possible from 5.0l -16l

Curves are going to look very different for the same power level is all I was trying to say.

Some of the 60cc saws are putting out more hp than the stock 066/395 I tested but no where near the tq.

 

[smokey7]

@Redfin tell me more about that nova!!!! I'm fairly involved in the heavy class 8 trucks down to the pickup trucks. I'm very intrigued with your pump setup there

 

[Bigmac]

They still around? JCWhitney?

I'm just talking hp/tq curves

1500hp is possible from 5.0l -16l

Curves are going to look very different for the same power level is all I was trying to say.

Some of the 60cc saws are putting out more hp than the stock 066/395 I tested but no where near the tq.

I hear ya on the different curves, in most forms of motor sports torque under peak is the winner in the real world

 

[NightRogue]

View attachment 245210
Cs1200 vs stock 395

View attachment 245211
Cs1200 vs 2511t

Discuss?

For me the big echo 1200/1201 has already won without the need of test or dyno, I've run the common big saws everyone runs mostly. 088/084, 070/090, 076, 395xp ported and so on.

Nothing comes close to 1200/1201 in big hardwood running long bars. The torque is 2nd to none and i prefer the slower rpm, you guys will probably laugh at me. The reason why it owns big hard wood is simply because the chain needs time to grab on the hardwood and scoop it out, something the dyno cant mimick and applies in environment.

Imagine you're shoveling snow in your driveway, you can dig a little and throw quicker or you can dig alot and throw alot slower. Now imagine its earth, you cannot dig a little because its lump. Even if you did its counter productive and you're doing less work, if you take your time stomping your feet on the shovel and move more material even slowly you're doing more work.

In big hardwood 1200 will win everytime, this hardwood is rock hard and dense. 395xp .404 ported barely got through, i cant imagine a stock saw. 1200 was smiling all the way and was asking for more lol

 

[Redfin]

@Redfin tell me more about that nova!!!! I'm fairly involved in the heavy class 8 trucks down to the pickup trucks. I'm very intrigued with your pump setup there

Oh thats not mine Man. Was just bustin Joes stones with the diesel pickup comment. Diesel drag cars are cool too.

 

[Terry Syd]

"in most forms of motor sports torque under peak is the winner in the real world" - but don't forget the other part of the formula - 'power to the ground!'

 

[Dieselshawn]

How about this, put a 880 stihl on the dyno, fill it with diesel and see how much power it will make......

 

[Sawrain]

They still around? JCWhitney?

Some of the 60cc saws are putting out more hp than the stock 066/395 I tested but no where near the tq.

I believe we will find torque per CC to be the limiting factor common to most saws, then it just becomes a matter of who can keep that torque going to the maximum rpms.

A very good naturally aspirated 4 stroke will be round 80-90ftlb per litre of displacement, there are 90s/2000 era everyday factory street cars (Honda S2000, BMW M3) that made near formula 1 specific torque outputs, as in their breathing efficiency/Volumetric efficiency was optimised to a very high level, they just didn't make the HP because they span under half the RPM of F1, though the real limiting factor, piston speeds, not wildly different.

Specific torque per displacement is kind of a hard limit, in 4 stroke world at least, torque and volumetric efficiency correlate very well, naturally aspirated volumetric efficiency peaks around 125%, achieving that at 8000 rpm is one thing, achieving it 16-20,000rpm is another, and that is how small NA F1 engines made power, RPM.

If you can maintain your torque at 11000 rpm as opposed to 8500 rpm, well there is your 30% HP gain.