how much timing are you running for haltech with single turbo

[gmonsen]

it has become fairly straightforward to set your air/fuel ratio to about 12:1 using a wideband lambda meter. however, i've learned very little about timing. like a lot of people, i started with both matt's and ari's base maps and worked from there. the car runs fine, but i don't really know much about whether my timing is really good or not. basically, my timiung just goes from the high 20's or mid-30's down to around 12-14 at full boost of about 17 psi. when i add or subtract timing down low in the boost range, it makes a noticeable difference in throttle response, though i haven't measured the diff on the dyno. up high there's noticeable diff. what is everybody running and what comments? what have you found out? thanks, gordon

This ad is not displayed to registered or logged-in members. Register your free account today and become a member on RX7Club.com!

[Red-Rx7]

I too am interested in this as well.

The general rule of thumb (from what I was told) was not to go above 17 degrees on 14-15+ psi of boost.

Mine must be set agressivly, for its at 15/16 degrees.

Mike

[Styk33]

Your timing is dependant on what you have done and what is on your motor. The more efficient your motor is the less timing you need/can run. So someone with a ported motor (depending on the porting) will not be able to run as much timing as someone like me with a completely stock motor.

Timing also changes with boost levels and with RPM.

On my stock turbo setup I was running 22 degrees at 14psi.

Not sure if this really helps.

------------------
<A HREF="http://ricemobile.net/" TARGET=_blank> </A>
Jay
The Ricemobile
94 Base w/ never enough mods
87 Base w/ never enough miles

[an_juan]

when you say above 17, do you mean 16 or 18? I have the Wolf set at 12 BTDC for 10 psi, about 7 for 15 psi. I find that the car is happiest this way. Anything greater than 12 (i.e 13+) and it knocks like a mofo. I am using 93 octane too, btw.

Also note that at idle, timing should be 5 BTDC per the service manual. I have my map set up as the RPM goes up, timing increases to about 30 BTDC upto 0 psi. Then, as boost builds to 10 psi, timing is retarded to 12 BTDC. I believe it's pretty linear in between.

I learned over the weekend that timing WAS way off by as much as 20 degrees! No wonder why it was knock so bad.
Comments, suggestions?

[gmonsen]

i found that some people with aftermarket ecu's, like the haltech, didn't lock in the timing between the haltech and the CAS correctly and so there timing was sometimes way off. some people don't have the timing mark set right. again, i think this is all part of the lack of discussion and focus on timing, which i still maintain must be some sort of black art.

in my original post i said it wrong, so i'll say it again: i seem to feel a difference in response down at low rpms and nothing up top. one tuner told me that he sees almost no difference above, say, 5000 rpm between timing of 10 and 15 degrees.

too much timing is clearly when you blow the engine, but i'd think somebody on the list must have some factual answer to how to set timing for certain boost and porting, etc.

...does anybody have an accepted standard way for measuring the effect of timing changes? egt's going higher or lower? J&S knock sensor coming on sooner or later? would the a/f get measurably leaner with more timing?

obviously, if there is something we could call "ideal timing", it would be relatively less the more ported your motor becomes. i would think you could support more timing without blowing the motor with "better" apex seals and springs or water injection. but would you gain any power by increasing the timing if you could?

also, i think timing changes are subtle. steve kan once told me that running 1 degree more timing at some specific higher rpm -- but not over or under that rpm range -- added 25-50 hp.

is it all just trial and error? or is there anything known to go by? oh, well...

-gordon