Starting my engine on a stand, issues arose |
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Starting my engine on a stand, issues arose |
malcolm2 |
Sep 29 2020, 06:16 AM
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#41
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Advanced Member Group: Members Posts: 2,745 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I have built a fresh 2.0 and borrowed a set of weber 40s to get her running, broken-in etc....
I bought a new single vacuum distributor with the flame thrower 3 module inside. Also bought the Petronix coil. I built up oil pressure, then connected the gas lines, fuel pump, and coil. Tach and timing light too. After a few tries, she started. As expected running very ruff. Back-firing thru the carbs. I loosened the distributor and tried to make some adjustments. That seemed to help the back-firing a bit, but not totally. I got the idle timing to what looks like 7 btdc, but it is tuff to work everything without a helper. I know next to nothing about these carbs, and about the same amount to tune them enough to bench run the engine, but I am looking into that. Any help would be appreciated on the carbs. I got it idling, again, very ruff. So I wanted to do the cam break in, so I rev'd it up to about 3000 and held there. Maybe a minute and the revs dropped and I had to putz with the accelerator to keep her going. Again up to 3000, same thing revs dropped. I have a note in to my distributor vendor about how this "rev limiter" on this module works. So three things here. She is still running ruff, back-firing etc...and there is the high rev cut-off. Lastly the carbs, any quick checks or adjustments there? Any thoughts or suggestions? |
Superhawk996 |
Sep 29 2020, 01:57 PM
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#42
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914 Guru Group: Members Posts: 5,876 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
@mark henry
Curious if you have used a Uni-Syn. That's what I've always used and had great luck with that. |
malcolm2 |
Sep 29 2020, 04:22 PM
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#43
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Advanced Member Group: Members Posts: 2,745 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
@mark henry Curious if you have used a Uni-Syn. That's what I've always used and had great luck with that. That Uni-SYn looks totally different. Does it work the same? Looks like it just sits on top of the barrel. Several on eBay for 1/2 the China one. I have a raised dis-taste for all things Chinese. I am sure you know why. |
Superhawk996 |
Sep 29 2020, 05:02 PM
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#44
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914 Guru Group: Members Posts: 5,876 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
That Uni-SYn looks totally different. Does it work the same? Looks like it just sits on top of the barrel. Several on eBay for 1/2 the China one. I have a raised dis-taste for all thing Chinese. I am sure you know why. Mine is ancient and pre-dates the el-cheap China imports. Probably made in Taiwan though back in the day - I'll have to look. The concept is the same. It measures a baseline airflow. I think it may be a bit more adjustable but since I've never used a snail, I can't say that with any certainty. It works on flat faced carbs without the need to insert into the venturi or velocity stack. I think you may be able to more precisely control the restriction it presents to the carb during measurement but at the expense of losing vacuum signal that moves the indicator up and down in the sight gauge. Other than that, everything Mark laid out for you applies. I was just curious why the snail type was his preference. I see absolutely nothing wrong with the snail type either. |
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