Timing Help Needed (302)

[jcwalsh1]

My Ignition Module failed and I ended up replacing the distributor cap, rotor, plug wires, etc before figuring out the problem. I also bought a timing light which could be making the situation worse.

I measured #1 TDC with a cylinder stop and it showed about 4 degrees on the harmonic. The rotor was aligned with #1. I had already painted a white line at 0 on the balancer.

When I move the distributor to 10 degrees TDC with the light the engine runs really rough. When I move the distributor clockwise it gets smooth just as the vacuum hits the coolant hose. At 700 rpm vacuum is in the green but the timing light shows 35 degrees TDC.

From the PO notes:
Engine bored .30 over
RV Cam, 2 stage over stock
Oversized valves
Headers into glasspacs

Is the distributor off by a tooth? I tried to do a test drive yesterday and it was backfiring under load.

Any help would be appreciated. I have read almost every previous timing post. All of the spark plug wires are correct. Firing order 15426378.

 

[jcwalsh1]

Video 2

 

[jcwalsh1]

Just found an old photo and it looks like the #7 plug wire is directly over the vacuum advance. Vacuum advance is pointed almost straight forward. I moved all the plug wires 1 spot clockwise and it still runs like crap, crazy high advance.

 

[Broncobowsher]

Don't have a single answer, but a few thoughts...
Very common for the distributor to go in a tooth off when you put it back in.
There are 2 different firing orders for a 302. The old 302 and the new 302/351W/HO firing order. Did you use the right one?
Setting the timing with the vacuum advance disconnected?
There are at least 3 different timing pointer locations for a small block ford. Possibly 4 now that I am thinking of one of the super rare oddballs. Mixing dampers and pointers will make for a confusing life. And even if everything is right, the outer ring with the markings on it can slip on the inner hub making all the markings useless.
How did you use the piston stop to find TDC? To do it right takes turning the engine over both ways so you hit the stop in both directions, and TDC is between those 2 stops.
you mention 10° TDC, but that isn't a real value. There is a 10° BTDC and a 10° ATDC. I've seen people not catch the A and B and get on the wrong side.
Vacuum gauge is a horrible way to set timing. Great for idle mixture but you will always set the timing to a crazy high value using a vacuum gauge.

 

[Broncobowsher]

And if you are still fighting this in 7 months I will be back in Shawnee for the holidays.

 

[jcwalsh1]

And if you are still fighting this in 7 months I will be back in Shawnee for the holidays.

I appreciate the offer but really hope I have it figured out by then.

 

[Timmy390]

Vacuum gauge is a horrible way to set timing. Great for idle mixture but you will always set the timing to a crazy high value using a vacuum gauge.

Yup...

Tim

 

[jcwalsh1]

I am going to cycle to TDC, pull the distributor and reinstall so #1 is in the right position. Let's see how that works.

 

[jcwalsh1]

Yup...

Tim

That's what I get for watching YouTube videos to learn

 

[NGABronco]

Me thinks that RV cam uses a 351 firing order, not the 302!!! Try that, if it works I can explain how I know later!!!
I think it's 13726548 ???

 

[m_m70]

couple things.......I can't see the vid that well so if these are obvious, my apologies....
Are the plug wires set in counter clockwise rotation?
Are you running your vac advance to ported??
Where are you getting your vacuum reading to the gauge from?

 

[gr8scott]

Me thinks that RV cam uses a 351 firing order, not the 302!!! Try that, if it works I can explain how I know later!!!
I think it's 13726548 ???

Would it run that smooth if that were the case?

Where are you getting your vacuum reading to the gauge from?

Looks like he's getting it from full manifold vacuum port, driver side of carb.

 

[jcwalsh1]

Would it run that smooth if that were the case?



Looks like he's getting it from full manifold vacuum port, driver side of carb.

I had the gauge on full vacuum. Metered vacuum was unplugged on the distributor.

Read a bunch more and think I installed the reluctor backwards. I did not know there were two pin grooves. Just pulled and reinstalled, engine is running much smoother at idle (10BTDC).

I will take it for a ride after work.

 

[NGABronco]

Well what happened???

 

[.94 OR]

It probably runs so well he hasn't come back yet...

 

[jcwalsh1]

Finally threw enough money at it.

When I pulled the distributor again that evening the oil pump shaft pulled out of the pump. In trying to get it reengaged I dropped it into the oil pan. Pulled the pan and accidentally broke the Fel-Pro gasket. Was ordering a new gasket and decided to drop the $230 on the Summit Billet RTR distributor. After going through multiple duraspark ignition modules this allowed me to eliminate the entire system. Bronco is running better than ever. Perfect 700 rpm idle @ 12BTDC. 40 degrees at 2500 rpm. I installed one blue and one silver spring and limited the mechanical advance to 18 degrees with 10 degrees of vacuum.

https://flic.kr/p/2pV1Hbh

 

[jcwalsh1]

My biggest surprise is that the engine temp is much cooler than before. It used to run 200-210 on a warm day. Driving to work this morning (65 OAT) it never went above 170.

 

[m_m70]

My biggest surprise is that the engine temp is much cooler than before. It used to run 200-210 on a warm day. Driving to work this morning (65 OAT) it never went above 170.

I think a lot of cooling issues are do to bad/retarded timing. First thing I say to check when someone has an issue. Glad you got your timing sorted and up and running good!