How do they do it on the VAG engine?
I have zero technical knowledge on the subject but I know when I upgraded the HPFP in my S3 the mid range was where it benfitted the most.
I believe they upgrade the piston, use coatings to decrease the friction and perhaps open up some restrictive areas, but I'm not sure. "
" Opening up the restrictive passages is not a solution for mid range where hpfp volume is limited due to the RPM of the pump rather than the size of the passages in the pump and rail. Fixing mid range is the hard part. "
Let's keep in mind he's running 100%, non-diluted E85 without Meth. So the Vargas HPFP upgrade might be sufficient for petroleum based fuels (Pump/Race Gas), it might not be enough for 100% E85.
Also stock HPFP is sufficient for petroleum based fuels. "
Originally Posted by Nugs
