I sprayed the Silverado for the first time this Saturday and want to be safe when I start increasing the shot. I started on a 50 shot but want to go as high as 200.

If I am running 91 oct gas on say a 100 shot with 4 degrees pulled would I still have to pull that timing if I used race(100, 109, C16 etc.) gas?

BTW, the 50 shot dropped my times 1/2 second. I did not have a wideband and I did not pull the plugs because it was just a 50 shot.

 

Anyone!

 

Ask your plugs.

You are probably fine but no one but the timing strap can tell you for sure.

 

If the timing mark on the strap is perfect on 91 and I run 109 in the tank to be more safe from detonation for a track event will the timing mark change?

 

Yes.

If the tune up is safe on 91. Add the higher octane fuel and make a pass. See where the timing mark lies with the added octane.

 

Just curious.. what are you using to pull timing?

 

I have both HPT and EFI Live and currently I am using EFI to reflash the PCM to pull timing but I am going to reflash it using one of there COS so I can pulltiming on the fly by activating the nitrous.

It gets tedious having to flash when you want to spray and I don't want to use the resister trick. I sprayed it for the first time this past Saturday and will be upping the spray slowly and then install the COS.