Any body know which number of A/F ratio can run with standard piston on the safety tuning??? Thx

 

Discuss the A/F Ratio?? SEARCH the A/F Ratio!

Depends on compression, boost, timing, octane, etc..

13-13.5:1 for max power.




Modified by ccfries at 10:10 AM 11/13/2004

 

Search. The internet is a very valuable tool... when it's used.

WTF is a "safety tuning"?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Haleiwa-Brando &raquo;</TD></TR><TR><TD CLASS="quote">Search. The internet is a very valuable tool... when it's used.

WTF is a "safety tuning"?</TD></TR></TABLE>

its like muffler bearings.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 255.255.255.255 &raquo;</TD></TR><TR><TD CLASS="quote">its like muffler bearings.</TD></TR></TABLE>

I thought it was more like the safety dance...
We can tune if we want to, we can leave your friends behind,
'cause your friends don't tune and if they don't tune then they're no friends of mine.

(Change your name Soup ****!)

-Chris

 

compression/timing and octane doesnt doesnt really have anything to do with A/f does it?

A/f depends on diff things. NA or boost? Na is usually a target of 13-13.5 or so at WOT and in boost target really should be 12 to be safe, but 12.5 will make a little more power. Now this is for Hondas. Supras I know you can run them leaner and its safe for them and they will keep making power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by itr206 &raquo;</TD></TR><TR><TD CLASS="quote">compression/timing and octane doesnt doesnt really have anything to do with A/f does it?
</TD></TR></TABLE>

Timing, maybe not. For sure compression does. Really high compressioin and boosted motors would act the same way, need to run richer to avoid pre-ignition etc. Lower compression N/A, not so important, so they just pick the A/F that gives the most power.

Also, I might argue that higher octane gas is less likely to detonate, so you can run it leaner... IANA tuner.

-Chris

 

stoich leaves no waste but runs the hottest cylinder temps.

12:1-13:1 optimal

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ccfries &raquo;</TD></TR><TR><TD CLASS="quote">We can tune if we want to, we can leave your friends behind,
'cause your friends don't tune and if they don't tune then they're no friends of mine.</TD></TR></TABLE>

Greatest post evaR!

 

i have to check on that. i never heard of running higher compression richer.

 

I mean, it makes sense right?

If you had a 13.5:1 compression engine, you'd have to tune it pretty similar to a 9:1 compression motor with .5 bar of boost...... during the compression stroke, both motors would get the same PSI of air and fuel at the peak (although the low compression boosted motor will have more air and fuel, because the volume will be greater). Same pressure, similar temps, means you'd want A/F and timing to be roughly the same.

Now, I'm talking very generally, and in practice who knows... but it makes sense to me.

(Edit, this is a GROSS oversimplification of the issue, the operating temps of these two hypothetical motors would probably be a lot different... hell, I don't understand how my motor doesn't blow up with an effective compression ratio of ~17:1 at 10 PSI. So, YMMV)

-Chris

 

tioming YES&gt; af &gt;NO.
ive had my cars tuned at the same target A/F on every diff compression ratio. I think you kinda have an idea, but as far as i know tuners dont go by compression for A/F, only timing maps.

 

Yeah, I way-oversimplified the problem. A higher compression ratio N/A motor is going to be cooler (making less power, less mass of air and fuel)... you'd need more fuel in the boosted motor to keep the temps down.

Or is there some other reason boosted motors need lower air/fuel ratio?

 

as you start making more power what happens? You start going lean. Boosted cars get tuned for richer content for safety. If something happens and it leans out a little you might get lucky. if you tune leaner and something happens, good luck.

I dunno kinda hard to explain. Its not all boosted cars either. Like i can tell you now Supras love 13-13.2 or so A/f. Hondas i wouldnt risk it in the world

 

I wanna learn how to tune a car, i've been a mechanic for about 5 years now plus all the time before that working on cars. Now that i have my own car and im starting to mod it i want to tune it so that it runs max efficiency. Whenever i look at posts like this i can never get a real clear answer on certain things, so does anyone have a good suggestion where to look to really to get started and learn how to tune the right way?Something that explains it all.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MiamiITR &raquo;</TD></TR><TR><TD CLASS="quote">I wanna learn how to tune a car, i've been a mechanic for about 5 years now plus all the time before that working on cars. Now that i have my own car and im starting to mod it i want to tune it so that it runs max efficiency. Whenever i look at posts like this i can never get a real clear answer on certain things, so does anyone have a good suggestion where to look to really to get started and learn how to tune the right way?Something that explains it all. </TD></TR></TABLE>

Try and speak with Jack from P1 automotive. His name is, B18CXR on the boards, he is very knowledgeable on the subject

 

efi101.com take the course

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ccfries &raquo;</TD></TR><TR><TD CLASS="quote">Or is there some other reason boosted motors need lower air/fuel ratio?</TD></TR></TABLE>

It is Heat. FI (on the avg) produce more than a NA motor would. Look at fuel as a coolant. More fuel (or octane) you have, the cooler the burn will be (if burned even).

 

this will be never ending discussion, since every1 have different opinion about a/f ratio.

 

Here is my dyno graph!!!

Compare with more lean A/F!!!


Hope can share with you!!