Off Road Vehicles banner

1 - 13 of 13 Posts

·
Registered
Joined
·
2,024 Posts
Discussion Starter #1
I just did a Basic tuneup to my 97 ram 4x2 1500 5.9 i have 60,000 miles on the truck.
so i decided its about that time, I did oil change, radiator flush, rear differential fluid changed and i added a xtra cooling additive, checked tranny since i serviced it at 45,000, greased all the fittings, spark plugs, wires, cap, rotor. the question i have is on the plugs specs say put the gap .35 but when i took off the origals they where almost at .40 gap is that gonna make much of a difference in performance?
i put the gapping where the old plugs where at and everything is running fine.
also i cant believe how far back the cap and rotor are located i had to take off the air filter system and i still couldnt see the cap i had to practically do it blind folded
 

·
Registered
Joined
·
502 Posts
a gap of .035 does seem kind of small but should be fine. Your old plugs would be at .040 from 60,000 miles of wear.

Even a gap of .040 seems small.

Which manual did you find this spec in?

Stock gap for my Mustang is at .054 but I have to run .035 because of the high boost from my supercharger.
 

·
Registered
Joined
·
2,024 Posts
Discussion Starter #3
i called in to a local truck shop and asked a guy for the gapping spec. he looked it up in a computer and gave me the .35
 

·
Registered
Joined
·
87 Posts
.35 is really small, but you didn't happen to mention whether or not you are running a stock coil. When you upgrade your coil, you can widen the gap. You can experiment be widening the gap until you feel that you have gained the best performance, but this is time consuming and quite a pain frankly.
 

·
Registered
Joined
·
1,057 Posts
On the 2000s, it's 0.40, on earlier trucks, it's 0.35. I'm not sure what year they switched. 0.35 to 0.40 should both be fine.

I'd go with 0.40, and if you start to get pinging, close it back up to 0.35.

If you open the hood, and look at the sticker on the body forward of the radiator, you should see the federal/calif emissions sticker, which should read out the stock gap for the truck.
 

·
Registered
Joined
·
502 Posts
not to be a pain on this point but these gaps are .035 and .040

.35 and .40 between 1/4 and 1/2 inch.. that is a bit much for a spark plug gap unless you have one hell of a coil.

Sorry its been a long day...
 

·
Registered
Joined
·
424 Posts
I found it to be a royal pain in the ass to replace the cap & rotor. I am small framed and I have to basically sit in the engine compartment to get to it. I felt like I was "milking" a cow when changing plug wires from on cap to the other.
As far as the gap thing goes - why not comprimise and set it at .37?

I mean - that way you could have a starting point and then go down or up from there!

Just a thought...

LUV24BY
 

·
Registered
Joined
·
1,057 Posts
Bill_L,

OY, yeah, I should know better than put them at 0.40 instead of .040. I'm not getting enough caffiene in my system I guess...
 

·
Registered
Joined
·
2,024 Posts
Discussion Starter #9
Its all stock on and in the motor except the K&N filter system but i put the gapping in between 35 and 40 and everything is fine no pinging or anything of that sort. it was just getting to the cap and rotor BEHIND the engine which was a pain in the butt
 

·
Registered
Joined
·
424 Posts
Welp, I feel like a real doof! .40 on the gap, hmmmmmmmmmm - I would think you would need a seond battery just to run the necessary size coil as Bill suggested!
Question: What, in putting in a "piggy-back" computer upgrade, would you gap the plugs at? Still a .035 or .040? Or the only time you change ignition/coil/wire/plugs to a high performance?
LUV24BY
 

·
Registered
Joined
·
1,611 Posts
My spark gap is set at .060 after the install of my hei system. Seemed a little extreme to me compared to the stock of .035 but the engin runs fine. (course the 70,000+ volt's running throught the system probably helps)

Later...
 

·
Registered
Joined
·
424 Posts
Ok, seeing as we are into the plug gaps, who is running what plug? I know the split fire is over kill - what is the brand of choice for a Dodge V-8?

LUV24BY
 

·
Registered
Joined
·
424 Posts
Thought this might be of some help or interest to those who have 5.9 360's - lot's of info, take a peak!

http://dodgeram.org/tech/gas/specs/5_9v8.htm
LUV24BY


_________________
My Project:
1997 Dodge Ram 1500 CC SB 4x4 "Sport"
360ci V-8, Auto, 3.55 Limited Slip
5.5" Fab-Tech Performance Lift w/ 4.5" rear leaf springs & Dual Shocks up front
35x12.50x15 Goodyear MT/R's on Centerline 15x10's
 
1 - 13 of 13 Posts
Top