Echo cs 490 porting

[bikemike]

Looks like it is running pretty well.

You done anything with the port timing?

No not yet that will happen after the staples gtg

 

[Red97]

No not yet that will happen after the staples gtg

I see. .325 or 3/8? 16/18" bar?

 

[bikemike]

3/8 pos vanguard on a 16"bar

 

[Red97]

3/8 pos vanguard on a 16"bar

Lo pro or full size?

 

[bikemike]

Lo pro or full size?

3/8 full chiz not the low pro

 

[drf256]

Finally home.

Hoping to open the 490 carb today.

If the RPMs don't jump, I may have to pull my jug and relieve my bottom like Red97 did.

Then hopefully a few cuts with the 20" and a try to fit the 14" low pro bar on the saw.

 

[Red97]

Finally home.

Hoping to open the 490 carb today.

If the RPMs don't jump, I may have to pull my jug and relieve my bottom like Red97 did.

Then hopefully a few cuts with the 20" and a try to fit the 14" low pro bar on the saw.

Keep us posted.

Only other minor thing I would try would be retarding the timing just a bit, before ya pull the jug off.

The lo pro may work pretty well on these saws...

 

[drf256]

Just watched my vid again.

Looks wayyyyyyyyy fat and slow.

I'm hoping the carb fixes that.

 

[Red97]

Just watched my vid again.

Looks wayyyyyyyyy fat and slow.

I'm hoping the carb fixes that.

I should be back home Tuesday. Hopefully have time to mess with the other carbs.

So what is your plan drf255?

Are you going to try and grind the venturi out to the max? Thin the shafts/ screws? Or take a little at a time?

Don't forget after you get your carb modded to test with and without the air filter.

 

[drf256]

I should be back home Tuesday. Hopefully have time to mess with the other carbs.

So what is your plan drf255?

Are you going to try and grind the venturi out to the max? Thin the shafts/ screws? Or take a little at a time?

Don't forget after you get your carb modded to test with and without the air filter.

My understanding is that the max diameter we have to work with is 16mm Joe.

I'm gonna remove the choke plate and shaft. Open the Venturi to 15mm and thing the shaft on the choke and throttle plates.

If the AF is really bad, I'm gonna cut out the fleece and add some metal mesh over it.

If I can get 14,500 out of it, I'd be happy. (Yeah right, who am I kidding-lol)

 

[Red97]

My understanding is that the max diameter we have to work with is 16mm Joe.

I'm gonna remove the choke plate and shaft. Open the Venturi to 15mm and thing the shaft on the choke and throttle plates.

If the AF is really bad, I'm gonna cut out the fleece and add some metal mesh over it.

If I can get 14,500 out of it, I'd be happy. (Yeah right, who am I kidding-lol)

Sounds like a great plan.

14,500 would be awesome, leave it set at 14,450

I think picking up the extra 1000-1500 rpm would make these saws limbing machines. Being quite light and nimble with 18-20" bars.

 

[drf256]

My goal is a 32.4538745% gain

 

[Red97]

My goal is a 32.4538745% gain

Lol,

You should have no problem getting 38% +.

 

[drf256]

Lol,

You should have no problem getting 38% +.

Nah,

Has to some ridiculous obscure OCD amount. 30% will not do when it comes to saws.

 

[bikemike]

Finally home.

Hoping to open the 490 carb today.

If the RPMs don't jump, I may have to pull my jug and relieve my bottom like Red97 did.

Then hopefully a few cuts with the 20" and a try to fit the 14" low pro bar on the saw.

When you pull the carb send a good pic of what the venturi looks like from the choke side of carb

 

[Red97]

Nah,

Has to some ridiculous obscure OCD amount. 30% will not do when it comes to saws.

Lol, I have good wifi here at the apartment.

Just checked my stock vs ported times vs rs chain

Stock 2 cut avg= 23.5
Ported 2 cut avg (stock chain)= 15.5
+34.04% faster

Stock= 23.5
Ported RS chain= 14
+ 40.43%

I am very happy with those gains. But still wanna find more.....

 

[bikemike]

Sounds like a great plan.

14,500 would be awesome, leave it set at 14,450

I think picking up the extra 1000-1500 rpm would make these saws limbing machines. Being quite light and nimble with 18-20" bars.

Well if they don't want to pull more rpm then keep the compression up and use a bigger rim

 

[Red97]

When you pull the carb send a good pic of what the venturi looks like from the choke side of carb

Do you have any close up pictures of the ones you have modified?

 

[drf256]

Lol, I have good wifi here at the apartment.

Just checked my stock vs ported times vs rs chain

Stock 2 cut avg= 23.5
Ported 2 cut avg (stock chain)= 15.5
+34.04% faster

Stock= 23.5
Ported RS chain= 14
+ 40.43%

I am very happy with those gains. But still wanna find more.....

I'd be happy too. Quite respectable.

I never did any stock cuts. Pertly cause I wanted to dive right in, and mostly cause I wanted to finally work on a brand new saw.

We should come up with some readily available constant for cutting. Like a 6x6 yellow pine railroad tie.

I know it will cost a bit, and you can't burn the wood, but it would give us a constant. Maybe even 2 0r 4 strapped together.

Might be a way to get better comparisons of gains on the web.

 

[bikemike]

Do you have any close up pictures of the ones you have modified?

I have a couple carbs I have done for 36cc saws.
This is a carb I built for a drop in big bore carb from a husky 136 and made it work for the echo 360t