BatmanGSX
01-18-2002, 08:46 AM
This is partially in ref. to the Norm/John thread:
I think tuning by 02 voltage on race gas is good but I wouldn't do it on pumpgas. The "sweet spot" doesn't exist on pumpgas in my opinion.
With my car I plan to start at about 24psi. I'm going to set it pretty rich and collect some Karman count data at the RPM where I hit full boost and then at the rpm where I shift. I'm going to take the Karman count at the shift rpm and see what % it takes to get it to about 1550hz. I'm going to adjust my AFC settings by that same percent between the shift rpm and max boost rpm. Then I will fine tune it to .86 all the way across. After that I will further tune it by knock, either with the AFC or just pulling timing myself with an ITC. Below max boost I will just tune for .86 at WOT. I will be doing all of this on 117 leaded/18G/550s. I'm going to mess with fuel and timing until I have 1550hz/no knock/.86v at my shift point. On pumpgas I'll just set the boost to 12psi and possibly inject a litte water.
I'm seriously considering hooking my AFC to 5-volt MAP sensor instead of the TPS and setting the cross over to 50/50 (or 15psi) What do you guys think of this?
If I run a 75 shot I'm going to use the ITC to pull an additional 2^ of timing before 5000rpms and 1^ after that.
I know most people would not consider using an ITC to adjust timing, just let the ECU handle it. But I figure you have a little more leverage to tune out knock while fooling the ECU into thinking it's doing a good job on it's own. If the ECU is happy and the engine is happy then it's a perfect scenario. If you have everything set up right in theory but the ECU is being bitchy it will screw you over.
The other plan I thought about was somehow shutting the knock sensor off to the ECU below a certain count, so like anything bellow "30" the ECU thinks it's at "0". I'm not sure how I will do this... some sort of opamp I suppose. A happy ECU and happy Engine is a good timeslip.
I think tuning by 02 voltage on race gas is good but I wouldn't do it on pumpgas. The "sweet spot" doesn't exist on pumpgas in my opinion.
With my car I plan to start at about 24psi. I'm going to set it pretty rich and collect some Karman count data at the RPM where I hit full boost and then at the rpm where I shift. I'm going to take the Karman count at the shift rpm and see what % it takes to get it to about 1550hz. I'm going to adjust my AFC settings by that same percent between the shift rpm and max boost rpm. Then I will fine tune it to .86 all the way across. After that I will further tune it by knock, either with the AFC or just pulling timing myself with an ITC. Below max boost I will just tune for .86 at WOT. I will be doing all of this on 117 leaded/18G/550s. I'm going to mess with fuel and timing until I have 1550hz/no knock/.86v at my shift point. On pumpgas I'll just set the boost to 12psi and possibly inject a litte water.
I'm seriously considering hooking my AFC to 5-volt MAP sensor instead of the TPS and setting the cross over to 50/50 (or 15psi) What do you guys think of this?
If I run a 75 shot I'm going to use the ITC to pull an additional 2^ of timing before 5000rpms and 1^ after that.
I know most people would not consider using an ITC to adjust timing, just let the ECU handle it. But I figure you have a little more leverage to tune out knock while fooling the ECU into thinking it's doing a good job on it's own. If the ECU is happy and the engine is happy then it's a perfect scenario. If you have everything set up right in theory but the ECU is being bitchy it will screw you over.
The other plan I thought about was somehow shutting the knock sensor off to the ECU below a certain count, so like anything bellow "30" the ECU thinks it's at "0". I'm not sure how I will do this... some sort of opamp I suppose. A happy ECU and happy Engine is a good timeslip.