Anyone running a 306 cam with a '730 and somewhat moderate compression (like 10:1).. ??

I've only got about 4 hours into this but, it barely makes it accross the lot. Occaisionally it will clear up and go sideways, then bogs.

I'm gonna start with another fresh bin tomorrow, from scratch, but i'm curious if you guys had any tricks. I found that a TON of spark advance smooths out idle around 800rpm. otherwise you end up with a 75-80kpa idle, which leaves almost 0 resolution left in the VE table for tuning. Rest of combo is in my sig.

This is an automatic car btw.

-- Joe

 

Drop your o2 constants a bit will help with the over rich idle.
I dropped them around 50-60 and my idle is better now.
(not perfect but not stinking rich now anyway)
Threshold fast, upper and lower thresholds.
Addys are 8496, 497, 498 respectively.

I also got the idle spark to occilate less by increasing the "SA lo gain threshold" at 81E6 to 1150 rpm.
Then I reduced the amount by half in the lower end of the "SA vS RPM error" table at 81F0->81F4 in combination with doing the same in the "retard vS RPM error" table at 81EB->1EBF.
The spark only moves about 3-4 degrees instead of the 8-9 that it previously jumped around.

My cam is not quite that rad (50-55 kpa idle) but it helped. You may need to be a little more aggressive with the settings to stabilize it below 1K.

IF this is AUJP based, did you up the (hardcode 800 rpm) idle limiter?
there's a link to the addy in the tuning guide for that one.

 

I have some from my 415cui in 8D code, not 100% tuned but I drove around some with it and it worked ok. Then I swapped to $58code and there I have a really nice tune for it.

Let me know If you want to take a look.

/N.

 

I also found that disabling the O2 sensor at idle helps to eliminate a variable while you figure things out. Get the timing side of things smoothed out, then the IAC routines and then go back and try to get the stock O2 to behave. I had better luck just running open loop and tuning via WB. Bigger cams don't like to idle at 14.7 to 1. My baby (compared to yours) 218* cam loved a 13.1-13.4 idle. I gained almost 10 KPA adjusting the AFR down to there from 14.7.

Excuse me if this is obvious to you, but you still have plenty of room in the rest of your VE table, it will only be in those 80-90 KPA ranges at low rpm's. Once you get the revs up you'll be able to use much more of the VE table.

Another thing I like to do is make a flat area in the spark and VE tables where it likes to idle. This will settle down timing and fueling changes and let you get a better feel for what the engine really wants. Then you can start to taper off the edges of your flat area to merge with the rest of your table.

 

TTT..

Anyone else running this cam on a 10:1ish motor. Curious what your idle map readings are..

-- Joe

 

Get in touch again, I may have some tips since I think our combos aren't so different.

 

Sounds good.

I'm gonna readjust my valves too one more time, just to make sure nothings too tight. I hear a little pulsing in the exhaust which could be the sign of a tight valve.

I'll be in #bish all day

-- Joe