thanks everyone for all the info. I was hoping to hear from more people with ignition upgrades to convince me to do it but I guess I should be happy that the stock equipment is good enough that spending the extra $200 on box & coil isn't worth it. Saves me money anyway. I'm just trying to get all the easy bolt-on hp/tq/gas mileage I can. My first fill up netted me 14.6mpg with a mix of highway and city driving. Not bad for a 351. I am going to replace the plugs, wires, rotor, and cap in the next couple weeks. I just dropped in a K&N filter and plan on mod'ing the airbox too. I'm also looking at the gibson side exit exhaust. It claims a 23hp@3500 and 32tq@2500 gain. Does anyone have experience with this system?

Thanks again!

 

one more thing, what exactly are sidegap plugs? Will these work well with a stock ignition vs using copper or platinum? Do I run these plugs, or any plugs, at the stock gap with a stock ignition or can you over-gap like msd/jacobs and get any benefit or will this effectively retard the timing? I remember the early 90's escorts with DIS were very picky about wires and plugs. They really only ran well with Motorcraft parts. Or at least this was my experience.

Thanks...

 

i don't know bout all this exhaust sytems and they're claims . my exhaust i had done for $200 i am very pleased with it . on the 90' it had two cats one small one up front that both pipes enter . then a short pipe to the second larger one . i had that second one removed ran 3" pipe to muffler (flowmaster type aluminized dual out) then 2.5" to the back with 3"x12" echo tips . it is a throaty but mellow sound , a bit more so since the air box mod .i had them split to one out each side behind the tires . looks good,sounds good, improved performance alot over the stock system and didnt cost me an arm and a leg .

 

Side gapping spark plugs is a method in which the end of the ground electrode is removed, exposing the center electrode. Gapping them becomes trial and error, and if you don't know what you're doing, you can ruin a set of good plugs. I have been doing it for years, and recently tried it in my truck. I noticed an improvement, but the PS91 coil might have played a part. Individually, neither mod made that much difference, but combined, it worked. Unfortunately, in my quest to diagnose what ended up being a bad ECM chip, I replaced the plugs with standard gap Truck plugs. I need a weekend with a few extra bucks and a few extra hours to really get back into my truck, and see what I can do now that the chip is gone, but that hasn't happened yet. Our first race is March 9th, and this Saturday is an open practice, so we've been busting our a$$es trying to get ready. I just finished buttoning up the engine last week, and we dropped it in over the weekend.

Sorry. Tangent.

Anyway, I would recommend Champion Truck plugs, set to the stock gap, for starters. You should drive it for a day or two, and then increase the gap a few thousandths, and drive it for a few days, etc. You'll know when you hit your sweet spot. Avoid platinum plugs if you plan on fine tuning the engine. Platinum plugs are install-and-forget-about-it plugs. They can't (shouldn't) be regapped.

Take care,
-Chris

 

chris
what is your honest opinion of accel plugs,tfi and coil?

 

I like U-groove plugs, but not enough to hunt them down.

never used an Accel TFI

Their coils are hit and miss. I like them better than MSD coils because they aren't as prone to "buzzing", like most MSD coils do, but their quality is about the same. You get what you pay for. I think the best stock replacement coil for the money (for Ford) is the Crane PS91. I still have never seen one fail.

FWIW, I HATE Accel street stock plug wires, but what do you expect for $20? On the otherside of that coin, the best wires I have ever used and tested were Accel 300+ race wires (solid core excluded).

Go figure.

Take care,
-Chris

 

ok thanks for the info

 

Well I tuned up my truck this weekend. I've only owned it 3-4 weeks now but whenever I get a used vehicle I like to go through all the maintenance because you never know how it was treated before you got it. I have replaced the radiator, all the hoses, and the thermostat. All were in really bad shape. The fluid was brown due to neglect. I replaced the radiator due to a leak. I put a new seal on the rear diff w/new fluid. I had the transmission and transfer case drained and filled. This brings me to the ignition.

I put new plugs, wires, rotor, and cap on yesterday. All were in poor shape. The wires look originial but the plugs were autolite platinums. I think motorcraft would have been the originals. The wires were motorcrats. Guessing from the shape of the plugs I would say the have been in for the last 50-60k miles. The autolites were very rusty. The threads were corroded. I was pretty surprised by this. rotor was worn and the coil terminal was corroded w/white powder. I sanded it and wiped it clean w/WD40. I put a conrad rotor & cap w/brass inserts in. I used bosch +4 platinums with bosch 8mm premium wires. Throttle response seems to be a little better, we'll see what mpg I get with this tank. While I did the plugs my brother took a 1/2 inch drill bit and put about 30+ holes in my airbox to allow my K&N to breathe better. It sounds like my fipk I had on my 95 5.0.

Here is my question: when I started the truck before the tune up it would start with a light touch of the starter. Even sitting overnight in the cold it would jump to life like no other 8 year old engine w/85k miles I've ever had. Once warm, you just touched the key and it would start. Now, after the tune up it takes a split second longer to start. How can this be? The parts I took off were in very bad shape. It runs fine just seems to take a little longer to start.

How ofter should the O2, egr, etc be replaced? I've been getting 15mpg w/easy driving between country 2 lanes @ 50-60mph and mixed with city driving.

 

Was the coil corroded?

 

the coil itself looked good, just the terminal where the coil wire plugs to was corroded. Not really sure what causes this. My dad had a problem on a Saturn where he had to periodically pull the plug wires from the DIS and clean them to keep them from corroding.

My first fillup since the tune-up was this morning and I got 16.6 mpg. My previous best before the tune-up was 15.3. I drive like grandma for mileage most of the time. From what I've read this is pretty good for a 351. Since owning this truck about 4 weeks now I've gotten 14.6, 15.0, 15.3, and 13.3 (gunning it around to get used to the 351's power). These were all before the tune-up. I'm looking into an electric fan and superchip. I wouldn't mind a little more pep and maybe another 1 mpg.

Also, the truck seems to start a little faster than right after the tuneup. Maybe the adaptive learning that the computer does is getting used to the new ignition parts???