I'm getting 2 degree's of knock at the top of 2nd gear , and am wondering what i could do to stop it . I get none in 3rd , and none in 4th (only tested 4th to 5Krpm ). It's a stage tune with a 2.99 pulley. stock plug's at .40 gap . Thanks.

 

could be several things. im having the same prob but with the 3.0 pully

 

pull a degree or 2 of timing on the top end and/or run higher octane if you arent already running 93-94.


YOU shouldnt be having any knock if you are running meth. if you are running the stage 2 tune, get tuned by someone familiar with meth injection ASAP. you are probably way too rich.

 

I always run 93, there are a few spots where i can get cam2 fuel (100 or 104) unleaded and try it. I ran a step colder plugs for awhile , but it seemed to make the car run worse . I guess i could try them again with a tighter gap. I do not have access to hptuners so i'm kinda stuck with the timing for now.

Thanks for the suggestions.

 

i have hptuners, been messing with it but its a pesky bitch lol. i am running fairly rich though.

what is the number for the stock plugs?

 

i missed where you said you had stock plugs. get those out of there asap and use NGK BKR7E. they are like $1.50 a piece. gap them at .035 or .038 you dont want to drop pulley sizes on stock platinum plugs. i believe they are PFR6E but dont hold me to that. i cant remember...

 

Nah man im running 1 stage colder plugs, just wondering if the stock plugs would be better lol. im taking the meth off anyway its gonna go on another toy im looking to get.

 

no stocks wont be better if you are getting knock. they will likely make it worse

 

I am looking at Getting OTT stage one...It comes with a tune/2.8 pulley/ belt/ Injectors...Hopefully i wont have any issues

 

the tune might need tweaked.

 

got a budddy with HTP tuners

 

(RUKKEE) my 07 SS/SC came with iridiums from the factory IFR6V -10G made by NGK, but had the AC Delco logo on the plug. The gap on them was 0.035 when I pulled them. I replaced them with NGK BKR6IX gapped at 0.035. Your knock maybe from the 0.040 gap. Close up the gap and should be fine. I want to do the similar setup you have. Stage 1 tune with 2.99 pulley. Let me know how you make out.

 

I put the colder plugs (bkr7e's ) back in last night @.35 lol , it's amazing you said that haha. Haven't scanned it yet , but i did a few pulls and it seemed fine, but i couldn't feel the knock with the original plugs either. thanks for the help.

BTW where in PA are you? I'm only about 30 miles from bradford PA.

 

I'm in the scranton area

 

i get 2 of knock at random times ... i dont think 2degrees is that bad now 4 or higher is a problem

 

^ Good to know, thanks. It wouldn't bother me so much except it's in the higher RPM range 6-7k rpm.

 

drive down the road slow but have your car in a high gear and you will read knock (sometimes)....

driving the car without letting it warm up you will read knock (sometimes)...

drive up a hill and shift at 3k and you will read knock (sometimes...

it just happens

 

he clearly stated at wot in second gear he said nothing about what you are suggesting

anyways op, yes close the gap to 35 it may not be knock it may be spark blow out causing it to read knock, also if your not getting it in third to be to worried at all, third is were you test for knock second could be false knock, also i would recommend a bkr7eix its a 1 step colder iridium that comes pre set at 35 gap...

 

Thx for the help HungryHip

 

That really isn't a lot of knock, especially if it's only in 2nd gear. Detonation/knock is usually worse under higher loads like you'd see in 3rd and 4th gear. If you're concerned about it and have access to some race gas like you mentioned that would be a good test. It's possible with that little knock the engine controller's knock algorithm is picking up some background noise (the knock sensor is essentially a small piezoelectric microphone tuned to detect the characteristic frequencies of detonation with that frequency primarily depending on cylinder bore size). If you increase the effective octane rating and it's still there I wouldn't worry about it if it remains at only a degree or two of timing and only at the top of second gear although you might want to watch overall timing to make sure it hasn't been affected and running lower than it should in other gears.

A couple other things to note on spark plugs. You generally want to run as wide of gap as possible without getting spark blowout for best ignition performance. The wider the gap, the bigger the spark and the more effective it can ignite the combustion charge. When you increase the cylinder pressure such as by running higher boost it is usually suggested to lower or close the plug gap because the denser combustion charge makes it harder for the spark to cross from the center to ground electrode, but if you're not having any spark issues then you don't want to gap down. It's also very well possible to gap a plug too tight which can lead to ignition miss issues.

Also if your car is running rich you don't want to run too cold of a plug range. The larger exposed ceramic area of the plug inside the combustion chamber of the cooler plug range will pull off more heat out of the combustion chamber and transfer to the cylinder head than a hotter heat range plug, but if you go too cold that can make the car more prone to fouling the plugs (which can be an especially big problem on platinum or iridium plugs that have smaller center electrode surface area than a conventional copper plug). The best way to verify if you're running the correct plug for your modifications is to watch and "read" the plugs. If you do a search there's a few good photo guides on the internet on how to tell if the combustion temps are too high, too low, or right where they should be.

 

Thanks alot blackbird, great info . I appreciate it.