Author Topic: things plug  (Read 371 times)

0 Members and 0 Guests are viewing this topic.

Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #20 on: September 27, 2015, 06:38:41 am »
lawnmower.

way rich.

fuel ring width = 0.126"

at top..... light color, no carbon
at middle ..... soft sooty fluff
at base.....hard carbon deposit
hiatus

Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #21 on: September 27, 2015, 06:44:36 am »
so far......just accumulating more data.

taking the average of the dodge, echo, chevy, and lawnmower plugs

range:
leanest....0.046"
richest.....0.126"

average of all individual measurements = 0.101" = running target

----------
hiatus

Offline aclarke

  • Nitro Hotsaw
  • *******
  • Posts: 1676
  • Karma: 172
Re: things plug
« Reply #22 on: September 27, 2015, 10:56:03 am »
Cool, takes plug reading to the next level. Very interesting.

Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #23 on: September 27, 2015, 01:07:59 pm »
.....maybe?  hahaha.

the one i'm still scratching my head about is the 562 plug of yours.

.....why is that thing is so rich/cold.

could see that it would have a rich idle.  the strato flap is shut, those dang transfers are big enough to drive a truck through.  would need to still be rich at mid throttle, when the flap is just a bit open to accelerate cleanly.  but when the strato flap is opened at high rpm....reason says it would lean out.

only thing i could see happening, is that the strato air plugging pulse first out into the exhaust........is making the fuel charge following super concentrated that is left in the chamber to burn.  too good of trapping efficiency in your ported motor.  donno?
hiatus

Offline aclarke

  • Nitro Hotsaw
  • *******
  • Posts: 1676
  • Karma: 172
Re: things plug
« Reply #24 on: September 27, 2015, 11:30:06 pm »
I monkeyed with the transfer tunnels on that 562. Re-contoured and reduced the area in an attempt to increase the tunnel velocity. Wanted to see how that effected the trans/strato bias. Seemed to work well.  Don't like not being able to easily changed carb settings.

The strato ms201. Is lean of peak as received and makes nice power gains richening them up. Gained rpm going richer.


Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #25 on: September 28, 2015, 05:53:29 am »
...those ngk plugs supposedly have a narrow heat range.  maybe they make a #5 plug in that style? ...one range hotter. difficult to see the ring if it's all one color.
the plug you are running looks as if it is not getting up to self cleaning temperature.

different brands may have differences in heat ranges, even if they are the same cross-referenced plug.   10mm or 14mm?

edit: just checked ngk site.  they do make hotter range plugs in that style.

stock: cmr6h
1 range hotter:  cmr5h
2 ranges hotter:  cmr4h

about 100C (200F)difference between each overlapping range. 

hiatus

Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #26 on: September 28, 2015, 06:23:26 am »
hiatus

Offline aclarke

  • Nitro Hotsaw
  • *******
  • Posts: 1676
  • Karma: 172
Re: things plug
« Reply #27 on: September 28, 2015, 09:23:45 am »
Thks for the info. I'll try a hotter plug and see.

Offline 1manband

  • Nitro Hotsaw
  • *******
  • Posts: 759
  • Karma: 52
Re: things plug
« Reply #28 on: September 28, 2015, 12:06:11 pm »
Thks for the info. I'll try a hotter plug and see.

..seems backward not to tune the fuel to the plug.  with the automatic screwdriver carb, not much else you can do.

once you start getting a burn on the ground strap, think you maybe pretty close on heat range.  they say timing, is read on the strap.

...one ignition manufacturer listed their small engine ignitions as putting out a little less than 30 mJ of energy.
compared to a typical MSD ignition for a vehicle runs about 135 mJ.

suspect that this has a lot to do with timing on these small engines.

hiatus

Offline aclarke

  • Nitro Hotsaw
  • *******
  • Posts: 1676
  • Karma: 172
Re: things plug
« Reply #29 on: September 28, 2015, 12:57:38 pm »
I experimented with a total loss electronic ignition on a 372xp race saw to see if it improved the performance with alky and nitro. Had issues with the electronics and never got it running right but I know it would be a huge improvement over stock. I'm gonna revisit this later.

 

Related Topics

  Subject / Started by Replies Last post
2 Replies
388 Views
Last post October 09, 2011, 07:23:58 pm
by Cut4fun .
56 Replies
1616 Views
Last post March 10, 2015, 12:02:35 pm
by dutchsawdoctor
2 Replies
214 Views
Last post August 18, 2014, 09:02:55 pm
by 1manband
4 Replies
1034 Views
Last post June 04, 2014, 11:54:13 pm
by 3000 FPS
8 Replies
788 Views
Last post June 21, 2014, 08:55:21 pm
by fossil
9 Replies
83 Views
Last post August 08, 2015, 12:01:40 pm
by 1manband
5 Replies
148 Views
Last post July 20, 2016, 07:33:47 pm
by 1manband
1 Replies
303 Views
Last post January 06, 2017, 02:48:19 pm
by Cut4fun .
1 Replies
161 Views
Last post June 06, 2017, 08:50:57 am
by Cut4fun .
9 Replies
343 Views
Last post June 18, 2017, 08:25:10 pm
by Al Smith