Tony

For those that have used the Sharktuner what amount of timing are you pulling from the WOT map under boost. How much is considered excessive?
I know the numbers may vary but im curious what others have done/seen. I definitley see the area around 5000-6000 rpm as needing some work at WOT.
Is the objective to get "zero" kocks...or...30....or 100 etc etc?

Ill post some more on the ST thread later but i wanted to post a topic on it here so the ST thread doesnt get too overwelming with stuff.


I spent the afternoon making about 20 runs from 0-140ish...roll ons from 30.60 mph...in 3rd and 4th gear. ..etc etc at 80-100% load. Now im working on the WOT area.

John Speake

Hello Tony,
A good starting point is 1 deg per # of boost. Then do your data runs. I usually monitor each cylinder knocks and then on the worst one tolerate up to 10 knock or so per pull through the rpm range.

AO

Tony-

The goal is to have zero knocks, but to not pull out too much timing that you loose performance. If you can get it to where you only occasionally get a knockon a WOT run... say 1 out of 5 runs you get some knock, I'd say you're doing pretty good.

You may want to adjust how much timing it pulls out when it senses knock and reduce the recovery time. If you leave these values stock it will zap your power. I beleive stock values are 6º retard with recovery of 0.3º every second.

Rick Carter

Hi John,
That's for 87+; correct? The cars without knock sensors already start with less
aggressive timing, so a good starting place would be pulling one degree of timing for every pound of boost above 5? Louie also recommends adding 3-5 degrees of timing at idle.

John Speake

Hi Rick
Yes that's for >87. The 85/86 cars are already retarded about 5-6 degrees in mid to top range, that's why they survive moderate boost OK.

Yes, Louie's suggestion of adding some more advance at idle does help smooth it out. I suspect it is set the way it is for optimum emmissions, but that's a guess.....

PorKen

On my '86 I'm running 5° over the stock idle and cruise maps, with the WOT map disabled. (At WOT, it switches to 3° over the cruise map.)

With a PCV delete, WR5DC's, 75°C/167°F thermostat (85°C/185°F block temp), etc., I'm using 89 R/M, without knock.

Tampa 928s

86 S/C
I have Auto Authority chips installed with my low octane loop connected with Tims kit, 5 lbs of boost. Does this sound right, after reading that the 86 can take a lot of timing I was worried about my AA chips having too much advance.
So I should be good to go?

hacker-pschorr

carry on....

Lizard928

Hey Ken, what is your max amount of advance atm? 45º?

PorKen

atm?

Looking at the cruise map, the max advance I might get would be 43+5, low load, 3500. At 6000 WOT, 30+3.

Lizard928

Interesting,

I am running at 3500+ rpm to redline under WOT 32º advance, and have no detectable knock.

I am running upto 50º during decel, and cruise I average around 45º

This is on 87 octane too.

AO

The issue with the 85/86 (and why Porsche pulled 5º of timing out) is because there are no knock sensors. The AA chipset basically puts all this timing back in. In a naturally aspirated engine the AA chips are probably okay and will not cause any damage (especially if you run a higher octane).

YOU ARE NOW RUNNING A BOOSTED APPLICATION! In theory (using the 1º per 1lb of boost rule) the stock chips should work perfect for you. By running with the AA chipset you have effectively gone the wrong way! you are now exposing yourself to even MORE potential for detonation. Because you have no knock protection, by running the AA chips, you are taking a significant risk of doing permanent damage to your engine!

You should be running with the stock chips at a minimum, and I would highly recommend you get your car SharkTuned when possible or purchase a set of chips from Mr. Murphy after he finishes Shane's car.

I don't think I can be any more clear than that.