View Single Post
Old 04-22-2012, 02:58 AM   #27 (permalink)
Piwoslaw
aero guerrilla
 
Piwoslaw's Avatar
 
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,751

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
Thanks: 1,337
Thanked 750 Times in 477 Posts
Quote:
Originally Posted by ecomodded View Post
Piwoslaw or Diesel Dave or anyone else if you have a fuel economy gauge and a hair dryer or as Stan suggested, run a heat safe hose from over your exhaust to your intake and note any differences
for the good or bad by preheating the air.
If I had a gauge I would be doing the test myself.
I could try one day when the engine will be hot, though now it's getting warm outside, so I'd be comparing a W(arm)AI with a H(ot)AI, I'd have to wait 6 months to test a C(old)AI.

But I wonder if this test would show anything conclusive. Since I don't have a dyno, then I'd just be idling on the driveway. At idle I see ~23% load and ~760rpm, while 80% and 1800-2200rpm would be ideal from a hypermiler's point of view.

Also, my turbo has variable geometry, so it may be that the amount of air getting scooped up depends on more than just the amount of exhaust gases coming out. For example, the ECU will see that the intake air is warm, so it will change the turbo's geometry to force more air into the cylinder. Then the only difference between tests would be the temperature of the air in the cylinder, not the amount, i.e. the amount of air (mass-wise) is constant, but if it is warmer, then it gets crammed in at a slightly higher pressure.
__________________
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell


[Old] Piwoslaw's Peugeot 307sw modding thread
  Reply With Quote