Well I just got back from my first real test drive since installing the GMS COP's and the BR7EF's. All I can say is RAPED APE!!!!!!!! My truck has never felt like this. It is so smooth when accelerating. This is not an exageration either. I am very please with the way they perform so far. I will have to wait and see how they do in the long run. My local club should be doing a dyno day next month so I will be able to see if they made any difference there.

They were too long but I just ended up trimming them. I cracked two of the COP's in the process, but they weren't cracked bad enough to make me want to return them. All and all I can say that I am pleased with this product.... Minus having to modify them slightly.

 

Good stuff,
Did you widen the gap on the plugs?


Thnx

 

Yes. I was running the TR-6's at 0.030 and I gapped the BR7EF's at 0.032. They run great so far. I got on the interstate yesterday afternoon and took it to full boost and it was smooth as silk. No spark blow-out at all. I will have to wait and see how they do when I stick the race tune to it....

 

Did your AF change?

 

I don't know. I haven't had it on the dyno since I installed them. I wouldn't think a more efficient spark would change the A/F...

 

If the A/F is measured after the combustion chamber and a more efficient spark burns more of the mixture, there will be less fuel molecules remaining in the exhaust, therefore the measured A/F should be leaner, no?

 

I'll have to look into that. I can understand the logic behind that assessment. I am going to my tuner today, so I will ask him.

 

A/F is determined upon the presence of free oxygen in the exhaust stream, not unburned fuel. Free hydrocarbons in the exhaust are another matter entirely.

 

Wouldn't the O2 Sensors pick up on it and adjust the A/F accordingly???

 

Exactly!

 

I spoke with my tuner today and asked him if I needed anything adjusted since I installed these COP's and he said no.

 

As far as these new cop's go,I wish someone could measure the difference in output voltage between the stockers.Im sure they help but Im wondering how much.SWThomas,what rpm are your shifts @ wot,and how much boost.

Thanks,
Frank

Ps. O2's only control fuel in closed loop operation.Open loop fuel is based on maf,and corrected w/ect,and act.