77 Black Max 175 (Video added)

[apd855]

I was looking at my timing advance arm and when I step on the hot foot it fully advances my timing before the butterflies in the carbs start to open, is this the way it's supposed to work.

 

[j_martin]

Re: 77 Black Max 175

Re: 77 Black Max 175

I was looking at my timing advance arm and when I step on the hot foot it fully advances my timing before the butterflies in the carbs start to open, is this the way it's supposed to work.

There's a short mark on the throttle pick up cam. That's where the throttles should start to open.

What you really need to do is get the maintenance manual for that engine, and go through the entire timing and synchronization procedure. (link-n-sync).

hope it helps
john

 

[JaseBosto]

Re: 77 Black Max 175

Re: 77 Black Max 175

If it runs fine, then the answer is yes. If not, then the answer is no....lol

 

[j_martin]

Re: 77 Black Max 175

Re: 77 Black Max 175

If it runs fine, then the answer is yes. If not, then the answer is no....lol

What Bootstrap is referring to is that sometimes a motor will be pretty boggy when trying to run just above idle, and often the fix is to just advance the throttle pickup a bit so the timing advances more before the throttles start to open up.

Your's sounds a little extreme, though. A dragster might be set up like that to keep it from fouling if they have to fool around at the starting line for a couple of false starts, but other than that, it doesn't make sense.

Stock setup is always safe and usually good performing. If you get too radical in changing the setup, you could do something like lean out and grenade the powerhead at mid throttle. Be careful, and do it right.

hope it helps
John

 

[apd855]

Re: 77 Black Max 175

Re: 77 Black Max 175

I have completed the link and sync per the manual but was just noticing the advance arm was advancing the timing before the carbs even opened. It appears that is the way it was designed to work. It runs good, a little doggy out of the hole but I may have it a little over proped. It was one of those things that didn't seem right. I wish I could post a video to demonstrate what I'm talking about.