Tuning Issues

[paxton5.0]

I had my car tuned today. It started pinging on the dyno using a timing curve that has worked well on every other cobra. The tuner backed the timing down to 17 and everything was ok on the dyno. He also said that my fuel pump was about maxed out. I took the car around the block and noticed that the car was pinging, Came back and backed it down to 15, now it seems ok. The dyno graph was also showing some weird things in the upper rpms.Anyone have any ideas about what could be causing these issues? Mods to the car are 2.8,FIPK, accufab, magnaflow catback. I also just had the fuel filter changed so I don't think that is an issue. The guy tuning didnt know what to make of it. Any insight would be greatly appreciated.

Here is the dyno graph.

 

[BUstang]

How are the plugs? You might need to upgrade to NGK6ix's. Also, what was ur duty cycle % at? IT should be ok, but its always good to check.

 

[paxton5.0]

It has Ngk6s in there now, I am not sure as to if they are copper or iridium. The guy tuning says that irridium will burn too hot and that I need copper plug. We also discussed that the gap may be way off on the plugs. Could this type of thing cause it to ping? The timing is what really gets me, I am having to run it on 15 max, just doesnt sound right to me.

 

[BUstang]

It has Ngk6s in there now, I am not sure as to if they are copper or iridium. The guy tuning says that irridium will burn too hot and that I need copper plug. We also discussed that the gap may be way off on the plugs. Could this type of thing cause it to ping?

yeah, gap is important. .32-.34 should suffice. Lots of twin-screw guys run the NGKix's so im not sure if i completely agree with your tuner, but oh well :beer:

 

[paxton5.0]

Ok, here is an update:
Pulled the plugs today and they were all gapped at 32. I talked again to my tuner about this again and he thinks it might be the reluctor wheel throwing things off. I did a search and did no come up with much. Anyone have any insight into this?

 

[akula51]

Are you in Southern Hemisphere or had the car been run for a long time prior to getting on the dyno? It'd behard to get IAT1 up above 150 here where I am this time of year, but getting the intake temp above that could cause the car to pull timing on it's own anddyno low, eh? I'd just be shocked with the pump maxing out with your mods at an A/F of 12...? I mean, if you were running way rich or something, but...?

Ack

 

[paxton5.0]

No, the car was actually sitting for about 30 min before we did the first run. He loaded a standard timing curve and it pinged. The datalogs were all showing that everything was fine, the car just didnt like its timing.

 

[About2bite]

Did you have fans on it? High IAT's will cause the car to pull timing on its own, I was having a similar problem and it turned out to be my plugs.

Where did you get your fuel from and how long had it been sitting in the tank?

 

[paxton5.0]

The car was not pulling timing on its own. The datalogs showed everything was fine. That is why neither of us could figure it out.

 

[About2bite]

Oh ic, I didn't read every post. So the fuel in the car is good?

I can't see the car not getting the fuel it needs or pegging the MAF but I wouldn't count it out

 

[akula51]

It's all ball bearings these days...

New belt when you put on the 2.8? Belt slip?

Ack

 

[paxton5.0]

The car did not appear to have belt slip. The only guess that either of us had would be that it could be something with the reluctor wheel throwing the timing off. Has anyone ever had this issue?