When I data log what gear do I need to be in?

[91talon27]

Is there a certain gear I need to be in or do I just drive and log then view what I logged? Also how much knock is too much knock at 16 psi on a evo3 16g. I made a run from 1st through 3rd and at one point I had a knock count of 18 that's as high as it ever went is this bad?

 

[Bmxr152]

Any knock over 5 should be a warning to you. Reduce the boost, check for boost leaks, is your tune good? 18 is definetly not to good. I always did my datalog pulls in 3rd starting at 3k rpm all the way to 7.5k rpm

 

[HIGHPSI4]

A long pull in 3rd works good. It will get you see the rpm band and is long enough to get good log data.

 

[BoostFrenzy]

I always did my datalog pulls in 3rd starting at 3k rpm all the way to 7.5k rpm

I thought you are supposed to start at 2k? That way if you have a fast spooling turbo (like the stock T-25/14b or any 16g variants) you can read what is happening at lower RPMs.

 

[Bmxr152]

Well i had cams and a prted evo3 so 2k was a little low

 

[always_broken]

When you do a pull, do you get on it? Or just gradually go up to 7.5k?

 

[TURBOGSX]

yes you want to get on it or you would not really see what happens when the boost comes on hard thats how you expect to drive the car right or are you going to slowly step on the gas when you race

 

[always_broken]

Car sounds scary as shit when I do a pull in 3rd gear all the way to 7.5. I still haven't gotten it down how to record and upload it on the laptop.

 

[Black_Bullet]

Generally the higher the gear, the more load on the engine more wind resistance etc. and the higher the chance of knock... For instance you may be able to hit 24 psi in 2nd gear with no knock, but 24 psi at the top of fifth might cause a shit load of knock.( Random example.) I dont recommend this, but my last good tune was off of 4th gear to make sure I dont have knock in any gear. 3rd works really good since it only carries you to about 90mph with 7k on a awd but it may not be accurate in you being sure theres no knock say if you get in the high rpms in the upper gears and your tuning on the edge...
But problem is 4th gear pretty much will take you to about 130 if you redline it so thats why im not telling anyone to do it. I only did it because theres this long stretch that connects to an on ramp and early early mourning its very feasable to reach 140 on with a very low window of getting caught or running into any other cars.
Tuning on the dyno in the high gears seems like it would work out despite the lack of wind resistence.
My speaking upon tuning goes same for simply logging your car as far as differences in knock w/ gears. Just my .02