Boost vs Timing on pump gas?

[0-60B4U]

I'm curious what you guys think is a safe amount of timing on pump gas with 20.5#'s of boost. My car is currently at 20.5#'s/15* timing on 93 octane. I also run 1 can of Torco with every tank of gas for insurance. Could I safely add more timing with 93/Torco or am I at the safe limit? Thanks!

 

[Oiljunkie]

If your going to run Torco you should mix it to bump up your Octane value to run more timing instead of using it as a safety cushion. Your tuner shouldn't have your tune on the ragged edge unless you asked for it.

JMO

 

[Weather Man]

Your running hard with the current combo.

 

[0-60B4U]

My tuner tuned the car for 93 only and he didn't factor for torco. I actually add torco just for my piece of mind. The only reason I asked about adding timing was to see if there was room left on pump gas or if I was at my limit.

 

[0-60B4U]

Do you really think I'm running hard with this combo? My tuner acted like it was more than safe. My FPDC is right about 80% and A/F is 11.8 at WOT.

 

[Ponyracer1]

I'd figure what ur total octane is and get it retuned if your going to run torco full time. I'm planning on running 90 oct with torco on my 3.4 at 21lbs. Hopefully justin at vmp will have my tune done soon.

 

[Bdubbs]

Mine tuner doesn't like running anything more than 17-18lbs of boost on pump gas! So that's what I'm going with. IMO op I'd never run that much boost unless I had e85 or race fuel.

 

[Riddick]

You could probably add a degree but I would just leave it where its at. There are tons of people running 20-21 psi and they seem to do fine. I personally feel its harder on the engine but several people have proved it can be done. I dont think to many people have gone over 15-16 degrees of timing on pump gas with 20 plus psi though. Keep in mind when running lower timing your EGTs are going to be higher. Also, since you are running more boost your IATs are going to be higher as well then those of a car with less boost.

 

[0-60B4U]

You could probably add a degree but I would just leave it where its at. There are tons of people running 20-21 psi and they seem to do fine. I personally feel its harder on the engine but several people have proved it can be done. I dont think to many people have gone over 15-16 degrees of timing on pump gas with 20 plus psi though. Keep in mind when running lower timing your EGTs are going to be higher. Also, since you are running more boost your IATs are going to be higher as well then those of a car with less boost.

I knew it would raise my IATs but I didn't think it would be a significant enough difference over my previous setup (3.0" pulley about 2#s less) especially since the car is a weekend toy and rarely driven hard. I didn't think about what it would do to my EGTs though. So should I consider lowering the boost or would you just run better gas (convert to E85, methanol injection, etc) so it can increase timing with my current setup? These may sound like dumb questions but I'm fairly new at this stuff so bare with me. Thanks for your input!

 

[Riddick]

Honestly, its all personal preference. If you want the most possible power out of 93 keep it the way it is. If you pulley down and add timing you are going to lose a little bit of power. Thats probably why people run higher boost and less timing is because it makes more power. I would call up the person who tuned your car and get his opinion. Another option is to call up some of the popular tuners on here and get their opinion as well.

 

[Sick SVT]

That's on the edge imo. I would rather see 18lbs with 18 degrees vs more boost and less timing. Now if you go e85 that's a different story. With e85 you could easily add 4-5 degrees of timing with your current boost as long as you have the fuel system to support it.