I'm all anxious about my tune tomorrow. This tuner installs mostly domestic turbos and superchargers but they've tuned quite a few imports as the tuner there is a fairly known import tuner here in the Houston area.

I'm all anxious about them tuning my timing and air fuels tomorrow and can't sleep.

I'm running super rich now and for probably that reason only putting out 322 rwhp and 287 rwtq on my stock vortech setup.

I was curious though how a tuner knows how much timing to take or give at any specific RPM as all setups are different. This tuner has worked on a handful of other G35s using the unichip (I think the APS turbo kits use it) and has had great success but I don't think he's done a vortech before.

I'm just anxious is all and wondering how these trained tuners feel out the level at which to give timing. Do they push until a knock sensor tells them they've met the max and dial it back a few degrees or how does it work?

I'm a scientist and I assume there's some scientific and methodical way to go about this as well. (plus a little bit of tuner black magic of course)

What is the sciences that goes behind setting timing?

I mean AFRs can tell you how much fuel to put in but what data output lets you know how much timing to give/pull?

What kinds of tools do tuners use to do this?

This is my first time ever getting a car tuned so please excuse my newbie question.

 

trial and error add timing till it knocks?

 

ok I've been learning a bit more...

maximum brake torque...

http://www.freepatentsonline.com/6609497.html

interesting patent on someone who was trying to find a solution to this with an invention but it has some good explanations in there.

from what I understand so far the tuners use a set of headphones and a devices that makes knock audible.

they tune up to the beginning stages of knock or pre-detonation and then tune back.

this process continues with each and every range.

 

another interesting discussion about the same :

http://www.gtr.co.uk/forum/103842-learning-map-2.html

 

Good read

 

^ yeah I know I'll never have the time investment to learn how to do this but it's always nice to know basically what you're paying someone to do and understand it a bit when they talk to you so you're not completely clueless.

 

Advance timing til it knocks, then back it off a degree or two. Backing it off won't decrease power, but will lower your egt's (exhaust gas temps). This is a good thing so you don't burn exhaust valves.

Of coarse, you could also advance timing til it knocks, then add some more fuel to cool the combustion chambers...

Lot's of different philosophies when it comes to tuning.

 

very interesting. learning so much from these reads. thanks for your input gothchick. love that you're a DIY tuner, wish I had that kind of ambition.

 

well civic, you and I will be learning at the same time. I street tuned my Vortech, but never put it on the dyno. Now I'm going with the STS kit, and I'll street tune it to get the AFR, then will take it to a dyno. I want to try to be as efficient as possible when I get on there, since they will charge an arm and a leg.

I have the "How to Tune and Modify Engine Management Systems" book, and I finally decided to crack it open tonight.

 

Tuning on the dyno is the only way to go for dialing in timing. When you make diminishing increments in power with each degree increase, you know you're reaching MBT. Keep in mind on a high compression motor (or under other "adverse" conditions), you may reach the detonation threshold before you reach MBT.

 

+1.. Fine tuning your timing map has to be done on the dyno and there is no point of advancing your timing if is not yielding you any power. The big question here is that how good is the shop's knock detection? How do they really monitor true knock?

 

I am almost through reading it. It's pretty helpful. I'm going to start tuning as soon as my O2 sensor is installed. After reading/researching for about 2 months, I actually feel knowledgable enough to feel ready. The thought of purposely making the engine knock is a little scary.

 

wrong thread sorry.

 

Part science, part experience, part voodoo. That's why an experienced tuner can charge $150/hour. There are lawyers who go to college for 8 years and don't earn $150/hour.

 

^ my tuner charges $250 an hour

 

With the Vortech only making <10psi, assuming you have the AFR set right you probably wont run into detonation with just advancing the timing; you'd probably start to lose power on the dyno with each increment before getting detonation. So creep up the timing until you start to lose power then back off.

 

have a target a/f and tune for that. start conservative on the timing and get the a/f right first. from there you can advance the timing until you hit knock. then retard a couple of degrees. a motor should be able to handle a few events of knock. however once you hit knock stop imeadiatly. i want to start learning to tune as well. best of luck to you

 

Nice thread Civic4982, i will be learning at the same time