Tuning tips

DDracomoderator23 Jul 2010, 08:56

Gary57 wrote:

Then first thing I would do is buy a Walbro...

As soon as money falls from the sky!!!

DDracomoderator23 Jul 2010, 09:03

RB25SX wrote:

Draco wrote:

I do agree that I need bigger injectors.....I did boost one bar with my preveous sx and was able to give enough fuel just with a bigger pump...

even with a walbro, 1 bar might be pushing it a bit on std inj's. Maybe just check your feul pressure to see if the regulator works. I know on my RB25 std regulator was at 4 bar. Think std should be 3.5-4 bar.

That is one of the items I still need to get, there is still plenty I want to do....when money falls out of the sky....

I am taking the sudden lean afr as pressure drop because of the fuel map increase at thet point, either pressure or flow....I will start with what I have, I have one of those"fong kong" high flow pumps that I will put in till I can get a walbro, just to see what happens and then if I still run lean there, I will turn down boost till I can buy bigger injectors and turbo.

DDracomoderator23 Jul 2010, 09:13

Thanks again for the advice guys!!!!

Appresiated!!!!

PPOWDER23 Jul 2010, 11:04

I think I have just spent on 2 hours reading this entire post, well done.... One I have REALLY enjoyed.

Draco, I am looking at playing around a bit as well with the self tuning thing and I think I now, Thanks to all inputers, have a dang good idea of where to start.

Thanks again guys....

TTHEO 3K - ZN25 Jul 2010, 16:26

Top thread, I got a few questions myself.

Hope you dont mind draco 😛

TTHEO 3K - ZN25 Jul 2010, 16:27

What is open loop boost & closed loop boost?

DDracomoderator29 Jul 2010, 08:13

THEO 3K - ZN wrote:

Top thread, I got a few questions myself.

Hope you dont mind draco 😛

No probs man, this is for all of us trying our hand at doing it ourselves....

GGuy29 Jul 2010, 12:14

THEO 3K - ZN wrote:

What is open loop boost & closed loop boost?

Open or closed loop boost control refers to the method of controlling the boost.

Open loop will make changes to the boost setting according to some stting or map, but the controller never sees what the actual boost is. That is, it has no feedback.

Closed loop control has a feedback loop, so the controller makes changes to the boost setting, measures the actual boost pressure, compares it to the required pressure (setting or map) and adjusts the boost setting if its different to the required setting.

Google open/closed loop control systems if you really want loads detail.

DDracomoderator30 Jul 2010, 15:49

Something I can add to the tuning of idling, in my preveous SX and this one I had like a "splatter" and slight miss here and there, that became normal to me, last night I played with the timing, lowering it quite alot on idling......splatter and slight miss gone.

If you can not find any other problems that can cause this....chanses are your timing on idle is to high.

GGuy31 Jul 2010, 16:07

Interesting, how did you find the timing affected the idling speed? I know some modern oem ecu's use timing to control idle speed.

RRudeBoy31 Jul 2010, 21:33

Guy wrote:

THEO 3K - ZN wrote:

What is open loop boost & closed loop boost?

Open or closed loop boost control refers to the method of controlling the boost.

Open loop will make changes to the boost setting according to some stting or map, but the controller never sees what the actual boost is. That is, it has no feedback.

Closed loop control has a feedback loop, so the controller makes changes to the boost setting, measures the actual boost pressure, compares it to the required pressure (setting or map) and adjusts the boost setting if its different to the required setting.

Google open/closed loop control systems if you really want loads detail.

simple -closed loop EBC = sucks, eratic boost and power, easliy visible on dyno chart

open loop or manual boost control ie: turbosamrt dual stage = awesome

RRudeBoy31 Jul 2010, 21:36

Guy wrote:

Interesting, how did you find the timing affected the idling speed? I know some modern oem ecu's use timing to control idle speed.

timing and fueling goes hand in hand - unless you 100% sure that your static timing is matched you waisting your time

more timing = leaner AFR , less timing = richer AFR - at idle chaning timing will have just as much affect as fueling

RRudeBoy31 Jul 2010, 21:41

Pinkfluffybunnys wrote:

Ok Can I go..

Cold start: timing advance or retard
fuel – Fuel enrich according to enrichment table , Timing advance 3 Degrees, cold crank timing 10 degrees

Cruising: timing advance or retard
AFR to look at.

N\A – 15.5 – 14.5
Turbo - 16.1 -14.7

Nope - 14.7 - 13.8 would be better, 16's would = lean

DDracomoderator02 Aug 2010, 07:42

Guy wrote:

Interesting, how did you find the timing affected the idling speed? I know some modern oem ecu's use timing to control idle speed.

turning down the timing did make my idle a bit slower, not too much, on idling my timing is now 9.8 but I braught my idling up with my idle control on the ecu with a slight richer afr on the fuel map.

75 posts

Sign in to reply.