I have a built d16z6 running the greddy turbo with an aem ems. I'Ve been tuning for 15psi and i have good afrs in boost 11.5 +/- .2 . the problem is i'm either getting misfires or detonation once past maybe 12- 13 psi up through 15psi. i wondering if my timing is bad. let me know if these timing numbers are good or if they are maybe to aggressive and advanced or maybe even i went to conservative and had to much retard. i'm running 9:1 compression on 93 octane pump gas.


these numbers are from 4500 - redline

15.4psi = 16.4
13psi = 18.9
10.7psi = 21.3
8.5 psi = 24.1
6.4 psi = 26.6
4psi = 29.1
2psi = 31.2


Modified by 93TurboSi at 4:32 PM 8/26/2004

 

I wouldn't go below 19 deg. of total timing. Have you check your plugs, what are they gap at?

 

First of all...make sure your base timing is fine.

A properly setup engine running around 12:1afr should not be detonating around 16degrees timing. 16 degrees is pretty low, but its a perfect place to start.

read your plugs and make sure you are infact detonating.

 

i am interested on this also

how many degrees do u guys consider optimal??
i know it varies from engine to engine, but theres usually a typical average

tought i would keep around 23 degrees on mine......

 

n00b question. when people ask, what timing was it at. what does that refer to? timing at max load at redline?

 

well i went and confirmed my timing on the ems and found i was about 3 degrees retarded to begin with. so at 15 psi i was really at 13.4 degrees of timing. from what it sounds like here that is really really retarded. Could being that retarded cause a small backfire. because the noise i heard sounded like it came from my exhaust like a low toned pop from my muffler.

so what kinda timing would be a good place to start with 15psi (yes i know every engine is different i just want a good conservative starting point.

would 19-20 at 15 psi be good

 

here are my new timing numbers. I haven't driven on them yet but let me know what you think. Also the timing is now synced very well.

again these are from 4500-redline with 11.5 =/- .2 afr 9:1 compression on 93 octane:

17.54psi = 16.8
15.39psi = 18.9
13.04psi = 21
10.70psi = 23.1
8.55psi = 24.8
6.40psi = 26.9
4.06psi = 29.1
1.91psi = 30.8
0psi = 32.6


is it looking good?

 

You are compensating for engine speed.... right? Not just running:

17.54psi + 6000rpm = 16.8 deg advance
17.54psi + 5500rpm = 16.8 deg advance
17.54psi + 5000rpm = 16.8 deg advance
17.54psi + 4500rpm = 16.8 deg advance
17.54psi + 4000rpm = 16.8 deg advance

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Freemantle &raquo;</TD></TR><TR><TD CLASS="quote">You are compensating for engine speed.... right? Not just running:

17.54psi + 6000rpm = 16.8 deg advance
17.54psi + 5500rpm = 16.8 deg advance
17.54psi + 5000rpm = 16.8 deg advance
17.54psi + 4500rpm = 16.8 deg advance
17.54psi + 4000rpm = 16.8 deg advance</TD></TR></TABLE>

well i'm basing it off the base aem startup maps and other peoples maps and they all have timing in the same load row go flat from about 4500-5000 to redline

so for example in load row 15.39psi at 500rpm timing is 1.28 and ramps up quickly to 18.5 by 4100rpm then timing is 18.9 from 4500 - 8500 (my redline is at 7600)

all the boosted aem timing tables i have seen go flat like this and have all the same timing through out the load row from about -4500-5000 up.

actually here is a screen shot of the timing table and graph:



does it look all right. all the other aemmaps look similar


Modified by 93TurboSi at 4:07 AM 8/27/2004

 

can some one take a look at my timing table and see if it looks decent. any suggestions would be great.


Modified by 93TurboSi at 3:48 PM 8/26/2004

 

bump

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tchleung &raquo;</TD></TR><TR><TD CLASS="quote">n00b question. when people ask, what timing was it at. what does that refer to? timing at max load at redline?</TD></TR></TABLE>

Normally, they are just refering to the what the computer advances the timing too. Most will just keep the mechanical base timing stock.

The actual value we are refering too is the Max. timing under full boost.

The amount of timing the engine should need is based on a whole bunch of factors, which is why its just best to dyno tune the car to find the sweet spot. Everything from compression to cams is going to effect how much timing the motor will need.

20 degrees is probubly the maximum amount of timing I would run on a pump gas motor with a decent amount of boost. Personally, I would rather have it conservatve than on the edge so I would keep it around 18.

 

ahh. gotcha. thx!