Jake U
New member
My car is a 2005 GP GT. My car ran fine stock but I wanted to get a little more out of it and make it fun to drive. About 6 months ago I added my first real mod to the car. I installed ZZP Headers and 3" exhaust with a catted downpipe. Which is where all my trouble begins. My car seemed very boggy under load and low rpm. I drove the car like this for a few months. The car is insanely loud even with a resonator and i figured it is very rich due to how boggy it drives. The next thing I did was add the HV3 intake and the ZZP PCM in hopes it would help with my car running rich and make it run like it should. The PCM did not help me in any way.
About 3 weeks ago I took my car to the performance shop in my town which is very well known for tuning and upgrading and does a fantastic job. I was getting my water pump replaced that day and I told him about my car running like hell and he hooked up his scanner. He could not pull any codes and I have never had any CEL,SES lights in my car. He did get the MAF fuel trims on his scanner and it was commanding -10% fuel at idle and -14% under a slight load. I then decided that I would let them have a go at tuning my car and getting it good to go.
My dyno tune was today and I was not actually there during the dyno runs because I had to work. I did get a call from the shop owner and he gave me some very confusing news. First that my car made only 160whp which I thought was a little low. Second that fuel injectors were maxed out at 4500 rpm. But my AF was very good in both the O2 and the MAF. He stated the AF was 15:1 at idle and 13:1 under power. the MAF was also within 5% of 0. All of this made no sense because I know that simple headers and intake insert will not max out stock injectors at only 4500 rpm, that seems very insane.
I am going to pick up my car tomorrow morning and I will have an in person conversation on what all was going on. I suspect that the values he was reading were the commanded values and not the actual values. I will be able to add more information on this tomorrow after I get my car .
About 3 weeks ago I took my car to the performance shop in my town which is very well known for tuning and upgrading and does a fantastic job. I was getting my water pump replaced that day and I told him about my car running like hell and he hooked up his scanner. He could not pull any codes and I have never had any CEL,SES lights in my car. He did get the MAF fuel trims on his scanner and it was commanding -10% fuel at idle and -14% under a slight load. I then decided that I would let them have a go at tuning my car and getting it good to go.
My dyno tune was today and I was not actually there during the dyno runs because I had to work. I did get a call from the shop owner and he gave me some very confusing news. First that my car made only 160whp which I thought was a little low. Second that fuel injectors were maxed out at 4500 rpm. But my AF was very good in both the O2 and the MAF. He stated the AF was 15:1 at idle and 13:1 under power. the MAF was also within 5% of 0. All of this made no sense because I know that simple headers and intake insert will not max out stock injectors at only 4500 rpm, that seems very insane.
I am going to pick up my car tomorrow morning and I will have an in person conversation on what all was going on. I suspect that the values he was reading were the commanded values and not the actual values. I will be able to add more information on this tomorrow after I get my car .
