what should i be gapping my spark plugs at for 93 octane at 20-21psi of boost and what should i be gapping them at for 97 octane at 23-24psi of boost?

 

Stock gap is .7 - .8 - I don't see any reason to change that on a stock turbo.

https://www.evolutionm.net/forums/sh...d.php?t=118252

 

I gap mine to .026 in. Above in mm

 

Had problem with boost blowing out my spark around 24psi. Had a local tuner upgrade my ignition with a custom setup and will never have problem again.

 

I am at .022

 

How many PSI you running at smokester? And is that with 8's?

 

Yes it is with the NGK BPR8ES and it is about 25psi on the 2.0L motor I had. that is with the HKS DLI spark amplifier also. I am keeping it the same gaps with the stroker motor/shooting the meth.

 

the reason i ask about spark plug gap is because i bought a turbo and supercharger book and according to that book and al other resources i have read that "...When you run higher boost you must regap your spark plugs to a smaller size. The reason for this is because when you pressurize your cylinder chambers it actually makes the gap larger with all the pressure built up. Therefore if you run higher boost it makes the spark plug gap even further apart, which may cause a Service Engine Soon light to come on."

And i never had a problem with the light coming on until i started running higher boost. that is why i asked what your guys are gapping them at.

I will try .022 tomorrow

 

It works for me, and if you have the BPR8ES plugs, they will need to be changed more often. I change mine at 4K miles. if I originally gapped them at .022, at 4K miles, I re-check the gaps, they are all at .030. so just be aware of that. you will be fine.

 

Oh and i am running the NGK BPR7ES, which is what Buschur Racing recommended with the my upgrades.

 

I change my plugs everytime i change my oil, every 3000 miles.... maybe that is to often but i dont mind

 

You will be fine my friend!! drive safely!!

 

thanks smokedmustang

 

Anytime!!

 

same here...im at .25 and i change mine every oil change....there only a 1.25 ..lol