1step colder or 2 step colder plugs, need to decide which plugs before tune day(by CHURCH)

[johnac08]

Will be getting a tune probably in 2 weeks. just waiting for speedie6 inlet pipe and should arrive today.
Just need your opinions before i get my tune. should i go w/ 1step colder(NGK) or 2 step colder plugs(HKS)?

before, i tested my car w/ 2step colder plugs, this is without the fmic, fullcontrol flash, dnp manifold, catchcan. The car doesnt really pull hard and idle is a little bit rough compared to 1step colder. so i installed back the 1step colder

yesterday, i installed back again the 2step colder and idle was a little bit better(maybe in my mind). car still doesnt really pull hard. compared to 1step. Probably during tuning Church can add timing on this.

I emailed Shawn Church about it and he said that i should go w/ 2step colder if i like to beat on the car.

What do you guys think?

anyway 1step or 2step colder my car still knocks at high rpms' even if you pull timing. running rich on that rpm and maximum timing i pulled was 3 degrees.


2007 MAZDASPEED6 GT Liquid Platinum Metallic
ENGINE MODS: CPE FMIC, CPE FullControl Flash, ATP Downpipe W/ High Flow Cat, CPE Dual Exhaust, CPE Xcel™ CAI, HKS SSQV BOV, DNP Turbo Manifold, ProSport Ceramic Header Wrap, SU Recirc Tube. CPE Engine Mount, CPE Standback w/ PNP, WOT Box Full Throttle/2Step, HKS Twin Power Ignition System, NGK 1Step Colder Plugs, Redline Tuning Hood QuickLift:Elite, Greddy Catch Can, Spin-On Oil Filter Conversion Kit, Mobil1 5w-30 FullySynthetic, Redline MT-90
INTERIOR MODS: MSD Dashhawk, TWM SS Stage 2 w/ Bushings, 52mm VEI Boost Gauge, 52mm Vent Pod
EXTERIOR MODS: VG Sharkfin Antenna, 18" 5ZIGEN 5ZR Wheels 43+ Offset with 225/40/18 TR1 Toyo Tires

[AutoXRacer]

I run the Denso ITV24 (2 step colder) plugs and I love them!!!!
No knock what so ever at WOT running 19PSI and 12.5 AFRs...

I say go with the 2 step colder...it will only protect your engine.

If you run 2 step colder plugs, you might want to retune your timing; colder plugs naturally act like retard timing. I am pulling timing on the lower end -2 degrees and adding 1 degree on the top end. I don't like to run too much timing...

[johnac08]

is there any negative effect running too much timing w/ no knock?

[Haltech]

Originally Posted by johnac08 is there any negative effect running too much timing w/ no knock?

You dont want to run more timing then what the car can handle. This is based on octane, boost, etc.

[skeeter149]

so is running 2 step colder on a mild modded car bad. i/e?

[ptperformance]

Damn this is really hard to direct you towards. I am going to say get both and try them out. I have personally ran both and to be honest with you the 1 step seem to work better at 18 psi and the 2 steps seem to like the 22 psi or higher boost levels (stock turbo). It really depends on how your car is set up and what it likes. Hell old rotaries that we use to run would have to be started on stock heat range then swapped out with the 4 steps cooler after the motor was warm. It would not start on the 4 steps colder when the motor was cold but it ran its best on them when we were on the track.

Find out what your car likes and take it from there.

[skeeter149]

will give the one steps a try first thanks.

[AutoXRacer]

Originally Posted by johnac08 is there any negative effect running too much timing w/ no knock?

You don't want to increase timing too much even if you don't get knock because you will be increasing cylinder temps...and too much heat will wreak havoc!!!

[LBV]

The rule of thumb on timing has been to advance it until you get KR and then retard it about 2 degrees ... for sure cylinder temps will increase but that may end up showing up as KR if it gets excessive (oe maybe not). A WI kit is perfect for when you want to advance the timing.