Too much Knock

[jarredsoon]

Hey.

I have my car running 94 octane gas, I have methanol injection, about 17lbs of boost and getting 6.6 dergrees of retard and knock that I can hear. The fuel pressure is measured at 46 with the vac on and 53 with the vac off....

How come I am knocking when I am not even running that much boost??

Also when I went to the track I put c16 fuel into the car and still got some knock, still had methanol injection and still only 17 boost??? When on the track I did not hear any knock but after the run I pushed the recall button on the scan master and it showed me some up to 7 degrees retard???

I had the car dynoed and the tuner said he got no knock with 21 boost and 94 pump gas/methanol. I can't seem to recreate those figures, I can't even get my boost up that high and I never changed anything since the tuning. They told me at the track to use c16 when WOT and I would not have to worry about anything, but the scan master tells me different..... I am gonna call the tuner tomorrow but I wanna know what you guys think?

I don't know why my car is knocking, I want to get the car to run with 22-24 boost with no knock but I can't even get rid of knock at 17 boost with c16 gas. WTF.

Jarred.

 

[DaJoker]

Mass air gone bad?? Could be cam sensor is off now?

 

[jarredsoon]

cam sensor was just fixed when the tuner was tuning. As far as the maf sensor I don't know, how would I check if that was good or not before getting another. Thanks Jarred.

 

[TT/Ameasap]

I had the car dynoed and the tuner said he got no knock with 21 boost and 94 pump gas/methanol. I can't seem to recreate those figures, I can't even get my boost up that high and I never changed anything since the tuning.

Need your combo and sm reading first... But reading what you wrote, you need to turn fuel pressure down in small increments and see if the KR goes away. your SM 02's should read 740's- 750's in top of 3rd @WOT. Looks like you turned boost down and didnt adjust fuel resulting in a rich knock condition.

HTH

 

[jarredsoon]

I thought if you ran rich you would not get knock??? and that knock only happened when you run lean. wouldn't running even leaner give me more knock???

 

[Boost231]

you can get knock from being way to rich as well. you need to turn the boost down and start tunning over again. with c16 and the alky off which you shouldnt run alky on top of the c16 you shouldnt have knock.

 

[jarredsoon]

how come you can't run alky with c16??

 

[TT/Ameasap]

I really doubt you are lean with 17psi of boost and 53psi of fuel....Oh and alky on top of that!

What is your full combo?? Injectors,turbo,ect.

I ran 42psi line off and alky all the way up with 50#injectors and ta49 turbo @25psi boost to give you an idea what I am talking about.

The only reason to run alky with C16 is to cool the intake temps.If your gonna run alky....Run it no matter whats in the gas tank.

 

[Boost231]

you can have to much octane to make max power. your best bet you be to run 110 and alky.

 

[Quiky One]

you can have to much octane to make max power. your best bet you be to run 110 and alky.

Yes but you can run C16 and alky and that will not cause knock. That was his question I think.

You want to run the lowest octane possible for your tune. 93 and alky should suffice just fine if I run 91 and alky and plenty of boost.

Jason

 

[Boost231]

true. i have run c16 and alky to get the cooling effect but i think you will have better performance from 110 and alky.

 

[TT/Ameasap]

true. i have run c16 and alky to get the cooling effect but i think you will have better performance from 110 and alky.

We are talking about a major tuning issue here. Not fine tuning the car for max power. I hope to see him posting later about that tho

 

[Boost231]

We are talking about a major tuning issue here. Not fine tuning the car for max power. I hope to see him posting later about that tho

yes i agree which i posted a few posts before this. The thread kinda got off topic.

 

[jarredsoon]

well I still have the fuel pressure at 44 with the vac on and I ran out of methanol so I put in some fresh methy hydrate. Still have 94 oct pump gas and boosted around tonight for about an hour.

I had 17-18 boost and I was not hearing any ping ping ping, but the scan master was saying 19.9 alot on the retard. But the car ran and felt really smooth. So I think this has gotta be false knock b/c I would hear some knock right???

I was wondering now if my methanol inthe tank had gone bad, evaorated a bit or something??? I know it was in there and I know it was spraying....???

I am now not backing off the gas when I see a number on the retard side of the scan master and I think this could lead to trouble if I really do get real knock. I am gonna look for something loose to cause fasle knock but I have not found anything obvious yet.