1128 Series Month

[MustangMike]

On another note, I have a HD-16 (no letter), a HD-16A, and a HD-16B. Anyone know what the differences are???

 

[Backtroller]

The HD-11 on my CFB hybrid works fanatastic. That beast of a carb came from Dave.

 

[dall]

i have a hd11 on my 10mm 044 my hybrid and a 046 but need to run the 046 to see how it does on it

 

[Redfin]

What's his name?

Dinner?

 

[MustangMike]

i have a hd11 on my 10mm 044 my hybrid and a 046 but need to run the 046 to see how it does on it

It did not really seem to improve my 044, so I put the ZAMA back on. It was also not as good as the HD-50 on my Dr Al ported 460, but the CFB Hybrid just loves it!

 

[Adirondackstihl]

i have a hd11 on my 10mm 044 my hybrid and a 046 but need to run the 046 to see how it does on it

Suppose an 11 would make a stock 10mm run any different than a 16?
16 was/is my favorite.
Not sure all particulars, but any saw I put them on seemed to respond very well to the adjustments made.
Make sense?

 

[dall]

@huskihl kevin did my 10mm and he said it is snappy and provides plenty of fuel for it

 

[Deets066]

Suppose an 11 would make a stock 10mm run any different than a 16?
16 was/is my favorite.
Not sure all particulars, but any saw I put them on seemed to respond very well to the adjustments made.
Make sense?

My hybrid has the 17 B on it. Runs and tunes great. I honestly can't see another carb with the same Venturi running any better on it.

But I'll probly try anyway

 

[huskihl]

@huskihl kevin did my 10mm and he said it is snappy and provides plenty of fuel for it

I didn't pay much attention to the finished settings, but I always start out at 1.25 turns each. I just fine tuned it from there. It's well within range

 

[huskihl]

My hybrid has the 17 B on it. Runs and tunes great. I honestly can't see another carb with the same Venturi running any better on it.

But I'll probly try anyway

I agree. Seems like something through the throat would have to be bigger to see and feel any difference

 

[junkman]

I had a bog off idle with 750 edelbrock ,put a holly 750 on it and no bog ,was not on a hybrid,was a big block chevy.

 

[MattG]

Ima show y'all a trick.

Gotta have a degree wheel on the engine to figure stuff out to begin with......but once these heights are established it's on.

My spec sheet on the MS460.

View attachment 75657

These are older specs........but this sheet was already in PDF, and is for an 1128 series.

So.......

Use this video to learn how to set height using the wheel and a piece of card stock.

Now.......

Hi Randy,

I'm somewhat of a rookie in all this. But I'm eager to learn. I understand the science involved, but what would be very cool is if you help me out with the port numbers. Or rather confirm/deny what I think they mean. So for the stock 460 you said:

Ex: 101.5*
Tr: 122*
In: 74*

So are the exhaust and transfer figures the degrees which the crank has rotated AFTER TDC at the point that the piston crown uncovers/opens those ports? But is the inlet figure the degree which the crank has rotated AFTER BDC at the which the piston skirt uncovers/opens those ports?

(I'm sometimes reading the 2 stroke tuning book by Bell, however it often refers to the port timings as durations, and so the numbers in the book seem a lot bigger than yours, hence my confusion).

thanks for your help and thanks for putting together threads like this one.

Matt

 

[hseII]

I had a bog off idle with 750 edelbrock ,put a holly 750 on it and no bog ,was not on a hybrid,was a big block chevy.

Word.

 

[RI Chevy]

My hybrid has the 17 B on it. Runs and tunes great. I honestly can't see another carb with the same Venturi running any better on it.

But I'll probly try anyway

Have you tried any others already?

Sent from my SM-G930V using Tapatalk

 

[Mastermind]

Hi Randy,

I'm somewhat of a rookie in all this. But I'm eager to learn. I understand the science involved, but what would be very cool is if you help me out with the port numbers. Or rather confirm/deny what I think they mean. So for the stock 460 you said:

Ex: 101.5*
Tr: 122*
In: 74*

So are the exhaust and transfer figures the degrees which the crank has rotated AFTER TDC at the point that the piston crown uncovers/opens those ports? But is the inlet figure the degree which the crank has rotated AFTER BDC at the which the piston skirt uncovers/opens those ports?

(I'm sometimes reading the 2 stroke tuning book by Bell, however it often refers to the port timings as durations, and so the numbers in the book seem a lot bigger than yours, hence my confusion).

thanks for your help and thanks for putting together threads like this one.

Matt

All my numbers are opening points from TDC. They will be the same either before, or after TDC...

 

[MustangMike]

Looks like I forgot to hit "post" last night:

CFB told me his previous hybrids liked the standard carb, then he changed some things, and they now prefer the HD-11. My Hybrid would not tune with the regular carb.

So now I have an 044 that seems to like the original ZAMA C3M best, a Hybrid that likes the HD-11 best, and a Dr Al Ported 460 that likes the HD-50 best. Go figure!

My Dr Al 460 ran very strong, but with the HD-50 is is at a new level. Ditto for the Hybrid, replacing the HD-50 with the HD-11 brought it to a new level. But the HD-11 did not impress the the 460.

You just have to find what your saw likes, but the differences are very noticable.

 

[MustangMike]

Holley Double Pumpers have excellent accelerator pumps (and good jetting), always put them on my cars!

 

[Stump Shot]

All my numbers are opening points from TDC. They will be the same either before, or after TDC...

 

[mdavlee]

I would ideally like to fit a Tilly 296 on one. Same pattern as a WJ. I tried 5 or 6 on my 46 and the HD 17 was the best. A zama was the best then quit running right. ☹

 

[MattG]

All my numbers are opening points from TDC. They will be the same either before, or after TDC...

Thanks, but I'm now confused regards the inlet, but that's probably because the action there is controlled by the skirt, not the crown and that's what confusing me. I guess I need to make a degree wheel up and prove it to myself!

thanks again