hi i am trying to squeeze some more performance and higher mpg out of my six. what spark plugs should i consider, i have heard that bosch platinums are good, but some people say they are crap, it has champions in it now. splitfire? autolite? what are you guys running? what about side gapping? how is this done? any help would be great. thanks chad

87 f-250
" if you are going to have a bear, it might as well be a grizzly"
4.9 granny tranny 4.11 gears

 

[font size="1" color="#FF0000"]LAST EDITED ON 13-Jun-01 AT 11:21 PM (EST)[/font][p]Side gapped plugs are made by trimming the side post of the plug with a dremel or similar tool so that it does not extend over the center electrode. The gap will be measured at about 45 degrees from perpindicular to the center electrode. On my truck it made starting quicker. Cant really say that I picked up any mpg, but the power does feel better compared to a stock plug. The gap must be checked more often that a regular gap plug. Use autolites as you will have to replace them more often. (The side electrode will burn off quicker.)

1977 F-100
300 I-6 / C-4 (soon to be AOD)
Offy C intake w/Edelbrock 500CFM
Hooker Ceramic coated headers w/duals, turbos, tips, and 02's
MSD6A w/Blaster Coil
Headlight relay system (Delanty style)
Overhead Mount FM-CD etc.
R-134 A/C system (I'm cool)

 

87f250:

I prefer the bosch platnium plugs. I've used autolites and champions then switched to the bosch platniums. I'm very pleased with the bosch plugs. I have also sidegapped the autolites and saw a slight decrease in mileage and noticed a heavy miss on a cold engine.

My vote goes to bosch platnium plugs gapped @ .045"


1981 F-150 2WD STYLESIDE P/U
4.9L 1 BBL CARB
C6 AUTO
2.73:1 LIMITED SLIP REAR AXLE
STABILIZER BARS FRONT & REAR
6100 LB GVWR PACKAGE
ORIGINAL OWNER
198,300 PLUS MILES
100% STOCK & UNREBUILT
BUILT FORD TOUGH!!!

 

How about bumping down from the 4.11. You'll loose acceleration, but gain mileage.

 

i like my 4:11. any way im not looking at huge milage gains from plugs alone, i am opening up the exhaust and getting a k&n filter, and also a coil, dont know what kind yet, any sugestions? i was just wanting to know if side gapping was worth the effort and what kind of plugs work best with the 4.9. i realize if i would get an overdrive tranny and may be some higher gears then milage would increase, but then it wouldn't be a grizzly would it might as well have a half ton or ranger. chad
87 f-250
" if you are going to have a bear, it might as well be a grizzly"
4.9 granny tranny 4.11 gears

 

well, here's my 2 cents-

i used to work for a parts store for a few years, and we all generally came to one conclusion when it came to picking plugs. Read all the hype and performance guarantees you want, but the best plug for the car is the brand it came with, except for a few exceptions. Here's how the big names go:

Autolite- Ford
AC Delco- Chevy
Champion- Dodge
NGK/ Nippon-Denso- Any asian foreign
Bosch- German

Now most fords are pretty forgiving to what kind of plug you put in. I've seen AC delco Rapidfires work just fine; Fords will even take Splitfires (which in my opinion is one of the worst plugs ever. I never had ay complaints about spark plug performance except those guys.) As far as the debate of platinums vs. standard copper, i'm not touching that with a ten foot pole. I've run everything from basic autolites to their double platinums, and personally i did't notice a thing. ( oh, by the way, they have one even more expensive then the double platinum now. They're titanium. if anybody has tried these. let me know how they are. i never sold any so i couldn't tell you).
As far as the side gapping goes, i say give it a shot. pick yourself up a set of the basic autolites (usually a buck a piece) and try it out. if it doesn't work, who cares? lousy $6 and some change down the drain.

 

Hello. I have used the bosh platnum and got 18 mpg, highway with those. I just completed a test useing a set of edge gapped auto lites on a 1000 mile trip and have averaged 21.8 mpg, highway of course. You will feel a difference with the edge gapped plugs. Give it a try you will not be dissapointed. I even put in a set of edge gapped plugs in my wifes minivan and asked her how it runs, she said it takes off like a rocket! An easy trick that works great! Greg.


1985 F-150, Black with black fiberglass cap. 300 6, auto trans 3.88 rear. Aluminum mag wheels, BF goodrich tires.

 

Does anyone know the website that shows you how to sidegap the plugs.
1987 F150 2wd
4.9L, 4 spd manual
31X10.5X15 BF's ATs
3" suspension lift
163,000 and counting

 

murphydo:

side gapping plugs explained and illustrated at link below:

http://www.performanceunlimited.com/illustrations/sparkplugs.html


1981 F-150 2WD STYLESIDE P/U
4.9L 1 BBL CARB
C6 AUTO
2.73:1 LIMITED SLIP REAR AXLE
STABILIZER BARS FRONT & REAR
6100 LB GVWR PACKAGE
ORIGINAL OWNER
198,700 PLUS MILES
100% STOCK & UNREBUILT
BUILT FORD TOUGH!!!