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Spark plug gap?

4.5K views 24 replies 13 participants last post by  ThisBlood147  
#1 ·
What is the facotry gap supposed to be set at? .045?

KenneBell told me to set the gap on the new plugs at the factory gap, I don't want to gap down my HT0's if I don't have to since I can't open them back up.

Also what do the plugs get touqed to?


Thanks,
Josh
 
#2 ·
Factory is .045. HT0s come .045. I am running my HT0s at .035
 
#3 ·
Torque plugs to 25 lb. ft.
 
#4 ·
hawgman said:
Factory is .045. HT0s come .045. I am running my HT0s at .035
Yea I know most people are gapping them down, hence the reason Im making some cheap effective gapping tools.

But KB told me to gap them at factory, which I thought was .045 as thats what setting my HT0's came at.

Know the torque settings for the plugs and stuff? I need to buy one of those manuals on dvd deals.
 
#6 ·
Hi there

Could one say buy colder plugs and some Granettli COP's. Then gap the plugs differently from factory settings to gain some more horsepower on an NA car without impacting reliability?

If so what plugs should I buy and what should they be gapped too? Is there any tuners who can provide the plugs, pre-gap them and ship them to myself?
 
#7 ·
jcovercash said:
Thanks, do the coil pack screws get a cetain toque setting too?
Just snug them up. Don't torque them down or your could break the plastic coil pack. Snug is good on them.
 
#8 ·
Gibbo_UK said:
Hi there

Could one say buy colder plugs and some Granettli COP's. Then gap the plugs differently from factory settings to gain some more horsepower on an NA car without impacting reliability?

If so what plugs should I buy and what should they be gapped too? Is there any tuners who can provide the plugs, pre-gap them and ship them to myself?
I personally feel that the Granetelli's may not yield alot on a N/A motor. There is a slight gain but the colder plugs/hotter coil packs are really out there for the power adder guys. Better off spending your money on a beefed up clutch/torque converter, electric H2O pumps, underdrive pulleys, or some drag radials.
 
#9 ·
Slofoot said:
I personally feel that the Granetelli's may not yield alot on a N/A motor. There is a slight gain but the colder plugs/hotter coil packs are really out there for the power adder guys. Better off spending your money on a beefed up clutch/torque converter, electric H2O pumps, underdrive pulleys, or some drag radials.
Electric H20 pumps? Do those actually make a difference?
 
#10 ·
Gibbo_UK said:
Electric H20 pumps? Do those actually make a difference?
They are supposed to. I personally wouldn't use one on my street car just because of the 3000 hours life on them. Doesn't seem long enough for me to justify installation and the possibility of installtional of another down the road.

But thats my personal opinion.

And the Torque for the Coil packs was 44Inch Lb's, found that out.
 
#11 ·
Gibbo_UK said:
Electric H20 pumps? Do those actually make a difference?
Yes. It will free up a few ponies, plus it is a continous 55gpm waterflow instead of a varying waterflow that is dependant on engine speed. If you race they are well worth it because you can activate the pump and fans with a switch without the car running and cool off your car alot quicker between runs.
 
#12 ·
jcovercash said:
They are supposed to. I personally wouldn't use one on my street car just because of the 3000 hours life on them. Doesn't seem long enough for me to justify installation and the possibility of installtional of another down the road.

But thats my personal opinion.
There have been many discussions as to how long that 3000 hour life span actually comes out to in miles. It ends up being basically the same as a mechanical pump.
You would have to drive something like 45mph a day for 3 hours a day for 3 years ( may not be exact, I don't remember, but it is close enough ).

Advantage to them is you toss a belt.... you could still technically drive your car because it won't overheat. Obviously you are not going to want to drive it far, and you would not have a charging system or power steering. But you could get a few miles down the road and possibly to an exit instead of being dead on the spot on the side of the road.
 
#13 ·
hawgman said:
There have been many discussions as to how long that 3000 hour life span actually comes out to in miles. It ends up being basically the same as a mechanical pump.
You would have to drive something like 45mph a day for 3 hours a day for 3 years ( may not be exact, I don't remember, but it is close enough ).

Advantage to them is you toss a belt.... you could still technically drive your car because it won't overheat. Obviously you are not going to want to drive it far, and you would not have a charging system or power steering. But you could get a few miles down the road and possibly to an exit instead of being dead on the spot on the side of the road.
Just to add to hawg's post... 3,000 hours is a long time. Assume your average speed over the course of several years is 40mph (which is probably on the high side), then a 3,000 hour life span would be 120,000 miles. After 120K miles, I would be expecting to replace a mechanical pump too.

And in the meantime, I'll have the advantage of far superior water circulation, cooler engine temps, and the added bonus of a couple extra hp. And for drag racers, it's a godsend for cooling the car down between runs.
 
#15 ·
lostsoul said:
what I'm worried about is the interaction between that and the alt. Does it push the alt to go to sheet and get those errors many were getting?
Maybe if someone totally drains their battery. But, a couple guys have gotten the P0340 code who didn't have the eH2O pump.
 
#16 ·
jcovercash said:
What is the facotry gap supposed to be set at? .045?

KenneBell told me to set the gap on the new plugs at the factory gap, I don't want to gap down my HT0's if I don't have to since I can't open them back up.

Also what do the plugs get touqed to?

Thanks,
Josh
If you are running the HTO's set the gap at .028. Torque the spark plugs to 28ft lbs and the coil packs to 44 in lbs.
 
#17 ·
kssSaleen said:
If you are running the HTO's set the gap at .028. Torque the spark plugs to 28ft lbs and the coil packs to 44 in lbs.
This is the first I've seen to gap the plugs to .028. Is that because he has the 2.6L Kenne Bell? Whay would others say .032 but in this case it's .028?
 
#18 ·
S197 GT said:
This is the first I've seen to gap the plugs to .028. Is that because he has the 2.6L Kenne Bell? Whay would others say .032 but in this case it's .028?
Kenne Bell told me to gap them at the factory gap which is .045 And im leaving them at that, Ill data log it and see if it looks like the spark is being blown out however.

Josh
 
#20 ·
Cali HP addict said:
I have never heard of .028. Jim III posted that all saleen equipped cars that leave their garage have a .032 gap.
What would be the advantage or disadvantage between .032 & .035?
A spark plug's heat range refers to its ability to dissipate heat. The "colder" the plug, the more heat it can channel out of the combustion chamber. In a high performance application, colder heat ranges may be necessary to handle the extreme temperatures brought on by higher compression ratios, forced induction, and high RPM's. That is why we use the HTO's in the 05's, especially for boosted applications.

A spark plugs' tip temperature and the voltage necessary to fire the plug are directly affected by the gap setting. insufficient spark plug gap can cause pre ignition, detonation and even engine damage. Most experienced tuners know that opening the gap up to present a larger spark to the air/fuel mixture maximizes burn efficiency, however, after they have raised compression and installed a turbo, they have to lower the gap (to ensure ignitability in the denser air/fuel mixtures). The main purpose of the spark plug is to ignite the air fuel mixture. The ignition system creates a electrical pulse that arcs across the gap between the electrode and the grounding tip. It is not the actual electricity that ignites the air fuel mixture, it is the heat energy generated by that electricity or spark. To big of a gap with stock ignition systems and big boost can cause misfires and detonation, (the electrical arc is interrupted momentarily and no heat is generated to ignite the A/F and thus a mis). Closing it up creates creates a shorter arc and thus less chances of a misfire.

Under tightening of the spark plug can cause plug overheating and possibly pre ignition. This is because one of the primary purposes of the spark plug is to remove heat from the combustion chamber, it does so by transferring that heat to the engine head. If the plug is not properly tighten it will not have sufficient contact with the head to transfer that heat.

Just my three cents.
 
#21 ·
S197 GT said:
This is the first I've seen to gap the plugs to .028. Is that because he has the 2.6L Kenne Bell? Whay would others say .032 but in this case it's .028?
.028 is where I run my plugs at. I feel that you have to read the plug, not look at a data logger. The spark plug will tell you everything you need to know about what is going on in the engine bay. I rev my Saleen motor to 7200 and my plugs burn georgous (mind you this motor is a OEM stock ignition with a Diablo piggyback). There is not a hint of fuzz, fouling or quenching on any of them. Everybody has a opinion on what to gap the plugs at. Just read your plugs and they will tell you what they like.
 
#22 ·
Have you tried a larger gap?
Reason I am asking is I have a 2006 T/Charged.. The car is breaking up around 3500 to about 4500,then it revs to the limiter freely.
I changed plugs from HT0 gapped at 35 to HT1 gapped at 30,and it cleared up.
I drove the car this way for about 2000 miles now its breaking up again?
i put new set of HT0 in today (stock gap),and no change.?
Any Ideas???
 
#23 ·
We were running the factory gap and were having problems with the spark being blown out in the onset of peak boost. After setting the gaps to 0.028 we no longer had the problem. Mike from Powerhouse was kind enough to trade me a set of gapped used plugs for my factory used ones in competition.:beerchug:
Derek
 
#25 ·
So would you guys say that it is better to err on the side of smaller gap on these cold plugs? I am ready to put my HTO's in, but I'm unsure whether I should go ahead and gap them to .035. I'm only running the 4 psi pulley on the Saleen blower, but I have experienced a pretty bad spark blow-out in 4th gear at WOT.
I'd rather gap them now and be done with it. But I've heard some say that regapping isn't necessary at low boost levels.....just as long as I'm running a colder plug.