a technical discussion, engine efficiency |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
a technical discussion, engine efficiency |
r_towle |
Aug 15 2005, 08:27 PM
Post
#1
|
Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
so, I have been thinking (not always a good thing)
If an engine is basically an air pump, and the objective is to make it as close to 100 percent efficient, why is the exhaust valve so much smaller than the intake valve? Forget emmisions, forget fuel delivery, just want to understand why this is so...it is so on most engines... Rich |
r_towle |
Aug 18 2005, 07:35 PM
Post
#2
|
Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
I agree, ljet leans out in the higher rpm's.
Again...I am not looking to build a motor that would see those rpm,s keep the power band under 5k, just like stock and ljet will handle it... Plus, ljet has many airflow sensors out there...lots of larger ones... But, with ljet, I dont think it would be needed till it hits 2.4 of above. Again, I can get mercedes injectors for a 4.8/8..same size etc. Raise the fuel rail pressure. build a 2.2 with the 4.8 liter injectors, stock air flow sensor...and of course put a O2 sensor in to monitor it all... Not a hig revving race motor, but a torquey street motor in the 140-160hp range.... Rich |
Lo-Fi Version | Time is now: 27th September 2024 - 09:46 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |