<html><body>Sounds lean too me. I think lifting the piston with the pin is a bit nebulous, as you cannot gauge the amount of lift. Using the SU tool set you insert rods into the pistons and you can then accurately lift each piston 1/32" which is the thickness of the rod. Another method is Color Tune in which you can see the richness of the mixture..these are much more accurate procedures than the lift the piston method<div><br></div><div>There could be many other factors, as discussed, but if all runs well at low rpms, then if properly adjusted, the car should perform throughout the entire range.</div><div><br></div><div>I just had a similar issue with my BJ8 cutting out at about 2500 RPMs, unloaded..turned out to be the white/black wire mounted to the master shutoff switch being frayed! Small things make big issues. Hank<br><br><div class="reply-new-signature"></div><p>-----------------------------------------</p>From: "Leonard Berkowitz" <drberkowitz@hotmail.com><br>To: "Healeys"<br>Cc: <br>Sent: Thursday January 28 2021 1:37:58PM<br>Subject: [Healeys] Another backfiring question<br><br>
<div style="font-family:Calibri, Helvetica, sans-serif;font-size:12pt;color:rgb(0,0,0);">
Hi all</div>
<div style="font-family:Calibri, Helvetica, sans-serif;font-size:12pt;color:rgb(0,0,0);">
<br></div>
<div style="font-family:Calibri, Helvetica, sans-serif;font-size:12pt;color:rgb(0,0,0);">
Just finished repairing and reinstalling the carburetors on my BJ7.
I thought I had everything adjusted properly. According to my
Haynes Manuel the engine speed should increase slightly when you
lift the piston a very small amount. Mine does that. My dwell
angle is where it needs to be and the car starts and idles nicely.
Also sounds beautiful when I punch the accelerator linkages. The
problem is that when I get it up to 60-70 mph I get what sounds
like backfiring into my carburetors. Also sounds like it doesn’t
have a whole lot left in the tank, so to speak. Does that sound
like I am running too rich or too lean? </div>
<div style="font-family:Calibri, Helvetica, sans-serif;font-size:12pt;color:rgb(0,0,0);">
<br></div>
<div style="font-family:Calibri, Helvetica, sans-serif;font-size:12pt;color:rgb(0,0,0);">
Len Berkowitz </div>
</drberkowitz@hotmail.com></div></body></html>