 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. |
|
|
| r_towle |
 Aug 15 2005, 08:27 PM
Post
#1
|
|
Custom Member  Group: Members Posts: 24,705 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 |
   |
 
|
  |
Replies
| messix |
Aug 16 2005, 12:30 AM
Post
#2
|
|
AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
i guess that vacuum assist power brakes don't exist? and the vacuum gage used to tune carbs? the low pressure created by the engine on the intake manifold is referred to as vacuum. [not in the absolute term]
|
|
|
|
Posts in this topic
r_towle a technical discussion Aug 15 2005, 08:27 PM
michel richard Cause on the exaust stroke there's a hard pist... Aug 15 2005, 08:49 PM r_towle I thought that there is a vacuum sucking the mixtu... Aug 15 2005, 09:29 PM Jake Raby ......... Because that about 20% of the air fuel m... Aug 15 2005, 09:38 PM r_towle thanx for that reply Jake...as always you get to t... Aug 15 2005, 09:40 PM Jake Raby Rich,
The summary I made was very general... With... Aug 15 2005, 09:43 PM messix the exhaust is at very high pressure after ignitio... Aug 15 2005, 10:06 PM lapuwali If you look at typical cam timings, the exhaust va... Aug 15 2005, 11:15 PM Brett W There is no vaccum in the cylinder. Nothing sucks... Aug 16 2005, 12:22 AM r_towle So, taking this knowledge, how can we apply it to ... Aug 16 2005, 12:24 PM lapuwali The cam in the stock engine was chosen more for em... Aug 16 2005, 12:46 PM Sammy Brett nailed it, there really isn't such thing... Aug 16 2005, 04:30 PM lapuwali IMHO, Brett didn't "nail" anything. Both of y... Aug 16 2005, 05:20 PM lapuwali Easy. Explain the technical terms first in layman... Aug 16 2005, 06:41 PM r_towle <... Aug 18 2005, 01:11 PM Jaiden Follow this link it will give you all the calculat... Aug 18 2005, 01:32 PM Mueller 
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 11th July 2025 - 02:24 PM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.
| 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 ... |