I know this is a hot topic on every board and I have seen so many mixed opinions but I would like to dredge this up again now that I actually own an F150. Mine is a 94 5.8l w/speed density. It's time for a tune up and I'm wondering what can be done to the ignition system that would be better than stock. Here are my questions:

1- Will MSD 6a actually help in hp/tq and/or gas mileage? What about overall throttle response, idling, etc. I prefer torque to hp due to towing and need low-end.

2- If I go with a 6a should I also get a hotter coil like the MSD blaster 2? Would a coil provide any benefits w/o getting the 6a?

3- What about plugs? Platinum vs copper? Which works best with stock ignition vs hot coil vs coil & 6a?

4- Also, with these computers do I have any control over timing or once I push the throttle does the computer take over and negate anything I might do? I run 87 octane due to expense but would like as much advance as possible on this fuel.

I know this is a lot of questions for 1 thread but I need to do my tune up before hauling a trailer 6 hours one-way in a few weeks.

Thanks!

 

My experience with the Jacobs unit was not favorable, and others' experiences with other ignition systems are a mixed bag leaning towards dissatisfaction.

Probably better to go with a couple of exhaust/intake mods.

-Mike

 

Depending on the miles on your odom. a new oem coil and platinum plugs with a decent fitting set of wires would be good. Don't forget your rotor button and cap. Wouldn't hurt to check base time too.

6 hours of towing is alot. Watch your temp and listen for pinging. Good luck.

 

I have a Jacobs system, underdrive pulleys, intake mods, and a Gibson cat back. If I could only keep one it would be the Jacobs.

1. Set up correctly it will help TQ and possibly a little at the upper rev ranges. My mileage average went up about 15%. I rarely dip below 15 mpg with the majority of my miles in town. '95 Supercab 4x4 with a 302. Idle doens't seem to have changed, throttle response improved.

2. Coil and good wires will benefit some. Box should help some more. I wouldn't bother with a box unless you already have good coil and wires.

3. I use the Champion truck plugs with my system. I do check other types/brands. I had some Autolite Platinums and got a little soggy throttle response but I am fairly sure this was due to pushing the gap over reasonable. They will go back in at next change to test this theory.

4. You can still change base timing, but the computer controls the curve from there. I can run about 14 degrees (10 is stock) on my 302 with 87 octane. Slightly less in the winter due to fuel differences.

As for the ignition, it was the first mod on the truck (second if you count a drop in filter). I would have sent it back in a second if it didn't work for me. At this point it has paid for itself in mileage increase, and I have the extra low end I needed in a heavy 302 powered truck.

There was no huge gains, but bang for the buck was better IMO than my exhaust, which cost the same amount. The previous owner drove the truck, and said it ran better than it did when he got it as a demo with low miles.

If you get a unit, get one with a money back guarantee. Check your mileage, do some timed tests, etc. If it doesn't work for you send it back.

 

With the Jacobs, what gap are you running? Did you get the kit with the correct harness or the universal unit?

Like I said, the RV ultrateam I had was a universal kit and made no changes for my truck. Wondering if the EEC-IV specific kit would be any different.

-Mike

 

I wouldn't spend the money on an MSD or Crane ignition box. My results were better with the stock box. A coil upgrade is good for peace of mind, but don't expect performance gains. As far as plugs, i swear by Champion Truck plugs. I have tried at least a dozen different plugs (I like to power-tune), and they were clearly the best (for me). If you plan on doing any future tuning, I recommend against buying platinum plugs. Platinum becomes very fragile after use, and regapping platinum plugs often results in a damaged platinum electrode, which often can't be seen, but which results in poor performance and often a miss at idle. If you are going to install it and forget it, then platinum plugs might be fine for you. When I installed platinum plugs, performance droped off a bit.

Take care,
-Chris

 

I've always had good luck with platinum. But I always throw them out every 12 months. Never had luck with replacement wires or anything that said Accel on it.
I hate Accel crap.

 

Accel Street Stock wires are nothing but pure junk. However, the best wires I've ever seen and tested were Accel 300+ Race Wires.

Take care,
-Chris

 

Have you used the Accel 300+ on the truck?

 

Yeah. I took the best 6 wires I had left over from my racecar, and cut them to fit the F-150. Worked great. Unfortunately, in my efforts to isolate what ended up being a bad chip, I replaced them. I will reinstall them next time, though.

Take care,
-Chris

 

Thanks, I'll try them some time. 7,8,9mm?

never mind i just saw it in your signiture 8.5 ahh

 

Taylor makes some very good wires as well. I have the "409"s (10.5mm?) on my mustang.I also have the taylor spiro pro's on my grand marquis. They seem to be very good quality. The spiro pro's are 8mm and about $40. The 409s are 10.5mm? and about 100$

scott

 

FWIW, Taylor wires are excellent, and would be fine for most applications. My experience with them wasn't so good because the ends came apart to easily, but I have not heard that alot, so it may have just been me. When testing for resistance, nothing beat the Accel 300+ wires, short of solid core. BUT, the difference between them and Taylor's or good MSD's wasn't enough to raise a concern in a stock application. General rule of thumb allows 1k ohms of resistance per foot of wire. The 300+ wires were more like 6 ohms, while the Taylors were around 30 ohms, and the MSD's were around 50 ohms (all still well below the 1000 ohm recommendation).

Take care,
-Chris

 

Mike,

I settled at .065 using Champion truck plugs.

My unit uses the stock coil as the trigger. I don't think it's specific to the vehicle, but I'm not sure.

 

I've settled on the Champions as well. Jacobs recommends the Autolites, but they have never been in stock. I did try the Autolite Platinums and got some soggy throttle response until the truck was up to temp. The truck warmed up quicker with them, so I do think they throw a hotter spark.

I plan on trying the platinums again at my next plug change. This time I will go back to my normal gap. On the previous test I had a monster gap (.075) as Jacobs recommends going .010 larger with the plats.

Have you seen the Irridium plugs? The tip is TINY!