Originally posted by warmonger:
Originally posted by gotapex:
Wired pump to get power directly to the fusebox, and grounded it to the chassis. Now getting full voltage to the pump. Only using the thin stock wire to handle the signaling.

Picked up a PLX R500 wideband O2 to monitor the AF and see how much boost we can run.

http://www.plxdevices.com/R-500_productinfo.htm



Fuel pressure up to 55 psi, and AF remains at 11.2:1 or below at 13 PSI at 7000 rpm.

Went to an airfield with a magazine (not sure I can name them yet). It was 103 degrees F, absolutely horrible for turbocharged vehicles. It ran 0-60 in 3.6 seconds, quarter mile in 12.2. Pretty disappointing, but not too surprising.




Wow! Nice if you asked me. You may want to raise that fuel ratio though to at least 12.0-12.2:1
Unless those heads are significantly different than ours, the combustion properties should be the same and 12.2 to one will yield significantly more power and still be detonation resistant if your intercoolers are working properly. I ran 12.0-12.2:1 just this weekend at 14+ psi of boost and nothing happened to the engine but gargantuan amounts of power!
I wasn't ready for that much boost yet so I turned it down but the point is I have stock everything in my 3L block with 10:1 compression, and nothing happened but the tires spinning out at 65-70mph when the boost came back on.
Tune it slowly during the lean out process of course and try 11.5, 11.8, 12, 12.2 and see how it goes. Should do it on a dyno so you can see if the torque levels start to fluctuate or get jagged as a sign of getting close to preignition.
You shouldn't get anything until 12.5:1 or higher in my experience.....on this engine that is.
Good luck with it.



I absolutely agree. We're running too rich right now. I'd ideally like to be right at the 12:1 mark or so. I'd say a little bit rich is ok just for safety, especially with this horrible west coast 91 octane gas.

Next up, we need to tune the boost levels up. Twin GT28R turbos can definitely operate higher than 13 psi before efficiency issues.

The shop that's doing the tuning is getting a dyno in soon. All the dynos I can possibly stomach are coming.

I'm guessing the next issue will be the tranny. Apparently, during heavy sustained roadracing, torque levels about 400 lb/ft become an issue.