Track night....slower?

[Texas gn]

Well, I guess the positive side is that I didn’t break anything but I did not achieve the numbers I was looking for. For some reason I was running a little slower out of the hole.
I am posting my PL file of one of my runs, hoping that I might learn a little more from it. I see for some reason I am getting some knock at the end of third gear. (never had that before….WB showing 11.0s)(fuel showing around 56 psi) Any input would be appreciated.

60ft- 1.89
1/8 -7.8
1/8 mph-91.9
1000 et- 10.2
¼ mile 12.1
¼ mile MPH 114.9

In tha past it was running 11.8s.... but the air was cooler.

 

[87chrisss]

Your 60ft is way off.. Car would run the same time as before if the 60 was in the 1.58 -1.65 60ft Colder air does help as well. If you have E85 around you should really look into getting that in the engine thats IMO. But good run like you said you didnt break anything

 

[Texas gn]

Thanks 87 chrisss….the last time I made the runs in the 11s my 60 foot was better. I sure was hoping to get someone to take a look at my file an see if anything was out of whack…just need a second opinion or two.

 

[Bescurred]

I'm not sure on you knock issue...was this on 93 and alky? Your sixty foot should be way lower. What tires were you running? Did you change anything from last time you were out?

 

[Texas gn]

I am running 93 and alky…..timing has been left alone on the TT alky chip and I am running MT DRs 275-60-15. I have had some time to think about it. I should of held the car a little longer and built more boost on the line. But the knock at the end of third gear is what is bothering me the most.

 

[Bescurred]

I don't have the software to look at your data logging. Were you shifting into OD? Or did you stay in 3rd the whole time? How much knock retard did it show?

 

[Texas gn]

I stayed in third. I have attached a snapshot of the run....from the powerlogger. boost was around 22psi.

Thanks

 

[bad V6]

If the boost was at 22# and fuel pressure was only at 56#, I'd be looking at the fuel pump. Your fuel pressure should have been in the 64-66 psi range, at 22# of boost. The fuel pressure should be set to 43-44# static (as directed in chip instructions) and increase 1 psi/1# boost.

 

[Texas gn]

I think you are on to something. I was looking at pasted runs and my fuel pressure was in the 65-68 range. This was a couple of years ago so it looks like the walbro 255 LPH is slowly losing pressure. Is that typical of these units? I installed unit Sep of 2009.

 

[aminga]

Look at the A/F rising as well. Either the pump is laying down or the FPR is bad.

 

[Texas gn]

here is a dyno run i completed a couple of years ago Notice the pressure difference? 10psi

 

[Texas gn]

 

[Pronto]

You should change the "pressure sensor" to Fuel pressure. Surprised you're not seeing more knock...

 

[Texas gn]

good one...i will jump right on that!

 

[Pronto]

Make sure your vacuum line to the regulator is good and other possibility is the diaphragm in the regulator is failing. Check the lines and replace the fuel filter. All easier to do b/f blaming the pump and replacing it.

 

[Texas gn]

I am on it ! Thanks for the input everyone. Nice to know there is good help out there.