| Slant Six Forum https://www.slantsix.org/forum/ |
|
| BBD butterfly holes? https://www.slantsix.org/forum/viewtopic.php?t=63558 |
Page 1 of 1 |
| Author: | Old6rodder [ Fri Apr 26, 2019 2:57 pm ] |
| Post subject: | BBD butterfly holes? |
Howdy, Gentlemen, I've switched to a larger throat BBD (non high hat style) on El Toad, and though quite happy with the mid range and top end results, I'm less than enchanted with the idle and draw down characteristics. I can't get the idle decently low even with the butterflies fully closed, and the draw down rate sucks. It appears that the pair of holes in each butterfly are enough to defeat my efforts there. So I'm considering soldering'em up and forcing the mixture to go around the butterflies, old style, thus regaining the idle set screw's adjustability. Or perhaps just one hole in each. Haven't done this mod before, so would like to hear pros & cons from anyone who has. |
|
| Author: | 62 val [ Sat Apr 27, 2019 8:23 am ] |
| Post subject: | Re: BBD butterfly holes? |
I had this old slant on a test stand for 3 or 4 month missing with the lash, timing and carb. It would not idle below 1200 rpm and plugs indicated it is running lean. It has the same Carb as yours, I roughed up the plate on both sides around the holes and Applied JB weld. It now idles at 600 and revs to 3000 without missing. The down side is I have only run it thru 3 or 4 180 degree heat cycles so I don’t know how the JB will hold up. |
|
| Author: | halfafish [ Sat Apr 27, 2019 12:19 pm ] |
| Post subject: | Re: BBD butterfly holes? |
I wouldn't worry too much about the JB Weld failing. I used it to repair a cracked block (leaking from the water jacket) on my ancient Ford when I was dead broke. All I did was rough up the surface and smear it on. When it dried I added coolant and drove the thing for another couple of years with no leaks. |
|
| Author: | Old6rodder [ Sat Apr 27, 2019 5:36 pm ] |
| Post subject: | Re: BBD butterfly holes? |
Yeah, I JB'd our float's drive engine (390 FE) radiator temporarily a couple years ago, and with decent prep it was still fine when I at last got a round twit this spring. Done right, JB can be impressive. I'm tolerable at mechanical soldering though, thanks to some time in the aircraft industry back when, so it'll be solder for me. Thanks, 62 val, that's about what I figured. Just wanted to find out if I was missing comprehension, and about to try something stupid (once again  ).
|
|
| Page 1 of 1 | All times are UTC-08:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|