I know this will be a stupid question and please try not to laugh.

I was going to change my plugs today. I will be putting in greddy race plugs with the heat range 9 & 10.

Now the OEM ones are 7 & 9. So do I........

A)
7=9, 9=10

or

B)
7=10, and 9=9

I am so embarrassed to ask

 

A

 

Go with A.

Why are you changing the heat range though? Will you have the tuning tweaked to take advantage of the heat range change?

 

Again.... A.

but what kind of power are you making?

 

I do not remember the exact conversation but while my motor was being rebuilt it was suggested that my housings had a bit of heat damage around the plugs. Cooler plugs might help reduce the chances of making the situation worse.

The car still needs to be tuned but it made 310 on a mustang dyno.

 

At you power level I would not spend the money on the Greddy plugs. For cars with your set up we just install stock trailing 9's in all four holes. This is cold enough so that the car performs well yet still starts and drives around town without fouling plugs regularly....and is much less expensive then race plugs.

 

Ya I know it does not make a lot of HP compared to others. Can someone explain why you need to tune differently for these plugs? Just curious if it's safe to drive till I get it tuned.

 

hey double j i have a ? for you. how many pounds of boost are you running? i see the mods that you have in your sig and i'm thinking that you are probably running at least 15-18 pounds right? i would think that with the mods that you have you would be putting down more power than that. did you hold back on your tune for some reason?

later, mark

 

also are your turbos seq or non? i have pretty much the same mods as double j almost the same,and running 18psi, i made about 380

 

16lbs ( 1.1 bar )

Every dyno is different, but once it is tuned I will run it again on the same dyno so I can see the difference. My hope is I can get 315-320.

After that I am going to try another dyno so I can get a larger number because that's what everyone else wants to see

 

if you want to change your plugs regularly and spend the money.. i guess go ahead. it wont be hard to foul them out though. I personally dont bother...

 

Your not going to foul these plugs lol, silliest thing I ever heard. I used the same plugs for over 25,000 km and this was running a rich idle due to low impedance 750cc primaries last year and the plugs were still fine when I took them out. Also, everyone who has used them on this forum has reported similar results. Only reason I changed them was because I had bought new ones. I still have the old ones as spares. Despite the plugs being "race plugs", you can use them on the street like "normal plugs". These plugs are very similar to the RX-8 plugs which are good for 70,000 km on an RX-8. And just because they are colder, doesn't mean your going to foul them.

Double_J, don't tell me you put the 10's in the leading lol?

thewird

 

I wanted to be sure I put them in the right spot. I traded the 7's for 9's and the 9's for 10's.

I am not expecting the plugs to make any more power. I am merely hoping that a cooler plug will reduce the chances of damaging the rotor.

If I lost a few HP or foul the plugs it is better than the engine.