Normally, I tune as much as possible in 4th gear, but recently I had been using 3rd gear to do some adjustments to my tune, and things were looking pretty good. Maybe a few knock counts here and there. Here is one of the nicer runs:




Then I decided to make a run in 4th gear just to make sure everything was good there too. I got this:

 

i never heard of someone tuning from 3rd gear...i have always heard of 4th because its nuetral or something...im definately not a tuning expert though.

 

It is the amount of load 4th gear excerts on the motor vs 3rd gear.

 

yeah i heard something like that...i wasnt what the exact issue was...thanks for that...

 

I tried to logging in 4th gear the other day and I was getting a 2count of knock in the areas that I was getting a 1 count in 3rd gear. The only thing that sucks is having to log up to 110mph in 4th compaired to 83mph in 3rd. 4th gear tuning I think is the way to go though.

 

yeah street tuning in 4th gear is definately a hazard...be safe

 

Getting 1-3 counts of knock in 4th gear on a street pull is not unusual, nor is it anything to be too concerned over.

Even if you dyno tune 4th gear, and get zero knock, you may get knock on the street due to the increased load on the car due to drag, and friction that increases engine load, where you wouldn't experience it on the dyno.

This is the reason you try to tune for no knock on the dyno in 4th. It doesn't guarantee no knock, just that the tune is safe.

Its a bit insane to street tune a car in 4th gear, even more so if your making big power as it takes too much concentration to drive the car and resist the temptation to glance at the computer. Not even addressing the Legal or safety issues on this topic.

 

Its the 9 count at 6500 rpm that surprised me a bit. I'm lucky enough to live in an area where I can safely street tune in 4th gear on a road that is virtually undriven in an unpopulated area. If there is no such road in your area, and you are limited to 3rd gear, then if possible, I suggest tuning on a hill which generates more load like 4th gear. If that isn't possible, then it may be wise to make your 3rd gear tune very conservative.

 

I experience that same thing too when logging on 4th vis-a-vis 3rd gear. Decided to retard the timing a bit with added fuel at 6,500rpm to 7,500 rpm and the knocks are gone.

Logging in 4th is quite a challenge also. I usually hit 160 plus km/h at 7,500rpm. Din really have a good look at the speedo....

But funny thing is there seem to be an odd 1 count of knock, even at low rpm say 3,000rpm during normal driving. Could be phantom knocks?

 

Try some higher octane fuel and see if it goes away or not.

 

We are a bit insane. We street tune 4th gear and even a little bit of 5th while watching the computer. Even flash the car while driving 90mph. It decels down to about 70 by the time the flash is completed and turns the car back on.

 

LOL!!!!! It is crazy

 

LOL Flashing while driving...now thats insane ROFL

Milburn

 

Hhaha who needs realtime tuning lol.

 

oh i flash the car all the time while we are still rolling!! thats fun when the steering go's tight! lol but we always tune in 3rd gear. i dont understand the fact of tunning 4th gear, i mean hell we always check 4th to make sure it looks good but it hasnt never been any different!