Setting base timing on 351 EFI w/ Explorer serp

[mattt]

In installing my Explorer front serp setup, I neglected to grind the back side of the bracket at the idler pulley for TFI plug clearance. Everything is installed and painted nice so I don't want to hack into it now. I had a thought.....instead of setting base timing at 0 and then advancing 10*.....wouldn't it be easiest to just drop the distributor in with the balancer at 10* for #1? If so, then I will only need a little bit of adjustment either way.

I have done this already, but just wanted to make sure I wasn't missing something by doing this. When I dropped the distributor in, I put the tfi plug about half way thru it's available arc so I have adjustment both ways. I then noted where #1 is on the cap and will place wires accordingly. Anything wrong with going this route vs. making a mess by grinding the back of the Exploder bracket?

 

[broncnaz]

You can try it but I dont think it will work out but each tooth of the dizzy equals like 30 degrees vs the 10 degrees you are shooting for yes theres a adjustment range but that doesnt mean you will be within range at that point. As the rotor will be out of firing postion. Its worth a try. but I forsee some grinding needing to be done.

 

[mattt]

One thing that I was unsure about was where the plug firing happens in relation to the rotor and the cap contactor. Does the plug fire when the leading edge of the rotor makes contact with the contactor inside the cap, or does there need to be half, full, or some other % overlap between the rotor and cap contactor?

Right now the way I have it....with the balancer showing 10* on #1, the rotor is about half way thru the cap contactor on #1.

 

[broncnaz]

Its hard to say as both the cap, rotor, reluctor ring, and pickup alginment all determine where it will fire. While I've never really researched it that much it seems that the engine would fire about when the rotor starts to come close to the edge of the firing point on the cap after all most setups the spark lasts probably 15 degrees or more of engine rotation. If you already half way through the roatation you could have less spark than the engine needs. So most likely you'll have to turn the dizzy to get it to run good.

 

[mattt]

Thanks for the info. I'm going to give it a go and see what it shows with a timing light once it's running as I know no other way to verify what I've got without a timing light. Hopefully that will be sooner vs. later

It seems like there would be ample adjustment either direction, advance or retard, with it set how it is now....but I guess I'll find out. I just didn't know if there was some particular reason that you HAD to start with the distributor at TDC on balancer. It looks like if I would have started with distributor at TDC, the #1 plug wire would have been around 12 o clock looking from front. How I have it currently, #1 is more towards 11 o clock.

 

[Viperwolf1]

Don't re-clock the wires on the cap or you will screw up the injector firing window. The stator is keyed to match the #1 position on the cap and it's timed to fire injector #1 probably 90 degrees before the spark plug fires, when the intake valve is still open. If you re-clock the wires the injectors will fire when the intake valves are closed. It will run just not as well. If you do any re-clocking turn the entire distributor and shaft to find a clear area for the TFI. Some fuel rails prevent this.

 

[broncnaz]

It might work but the way you have it set your going to have to retard the timing so really your only moving in one direction. it all depends on how much clearance you have so your ample clearance eitherway may not work out that way.

 

[mattt]

To clarify....I wasn't going to change which wire goes where on the cap. I turned the whole distributor and will keep #1 wire on #1 terminal on the cap. I took a picture to show how it's currently dropped in. You can see #1 'sharpie'd' on the cap. This is the orientation of the distributor in the block with 10 BTDC lining up with pointer on the balancer.
Basically what I'm looking for....is there any issue with having the whole distributor clocked as it is in the picture? I read Ryan's write up on fordfuelinjection for setting timing and his write up emphasizes starting at 0.

I have read a few replies where people talked about fuel rail interference. What fuel rails tend to be the most problematic? Mine appear to clear just fine. Is there one particular fuel rail that hits, and where does it hit the distributor or TFI?

 

[Viperwolf1]

Some of the explorer driver side rails run further forward and hit the distributor body. This limits the range of adjustment when the distributor is clocked at that angle. My mustang rail does the same thing but I have just enough clearance to make it work.

 

[mattt]

I guess I just got lucky then using the truck fuel rail in the picture...no fuel rail interference yet.

Any other thoughts on how the distributor is re-indexed in the block? It shouldn't matter if my thinking is correct....but I'm second guessing myself because I 'mostly' understand, but not 100%, the hocus pocus of timing.

 

[fungus]

I would think you'd be able to drop the dizzy into the block with whatever orientation works for you. As long as the cap/ rotor/ #1 cylinder are all jivin' as they should. Makes no difference where that TFI module is pointing.