Boost+Timing+Octane

[o2camaross]

OK this thread is for people to post up what PSI, timing and octane they are running. Ive been scratching my head trying to figure how hard I can push my 5.3 with 93 pump gas so hopefully this thread will help. When I had the truck tuned it was tuned for 9psi and 16 degrees of timing. I recently turned it up to 13psi to beat a modded 5.0 and I was wondering how safe it is. I know I shouldnt have done it without running a log to see if I have any KR but it ran like a scalded dog. AFR was right at 11.0. How much boost/timing can I safely run on pump 93 octane? No meth right now and E85 is out of the question in Louisiana.

[ecld_07]

8lbs, no meth, 91, 16* has Been good an safe for me

[George C]

I tend to push stockers very far.

When either on racegas or pure meth injection i tend to use the rule of .5* reduction for every lb of boost

Using the tables were if iats are over 120 i start yanking timing. If ect are over 180 i pull timing some

Pure 93 ill use 2* deduction for every 2 lb of boost

[o2camaross]

So with that method George, where do you start the add boost/ reduce timing method

[George C]

Around. .60 g/cyl would be my highest timing then it ramps down till 1.20 were it flatlines. As for amount of ramp will depend on how your timing table looks. I also use decimal points to help with transitions.

As for different boost levels i have different tunes for different psi

I also have track tune and street tune. I wouldn't chance running track tune on street

[George C]

Also note as power level rises so will heat range of plugs. For power in the 700s br7ef is to used. For power in the 800s i use a 8series plug (exact number is at home).
Using this method has shown good marks on the strap.

As power rises so will your plug gap close

[o2camaross]

Ok, Im running br7ef's right now so that should be good. I need to do some logging. From what Ive been reading it sounds like I was pushing it a little with 13 psi, 16 degrees of timing and 93 octane.

[DBRODS]

Every combination out there is different. Why don't ya'll learn how to read plugs and give the motor what it wants?

[o2camaross]

doesnt that require cutting them open or requires special tools?

[DBRODS]

I use a lathe, but you can use a 1/2" drill and a hacksaw.