Intake length vs torque, Just anthoer carb question No boobs |
|
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. |
|
Intake length vs torque, Just anthoer carb question No boobs |
Joe Ricard |
May 18 2005, 02:03 PM
Post
#1
|
CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
So I have short intakes and 44IDF's with 38mm vents
How long of an intake should I go to with these carbs or should I go to 40 IDF's with 32 vents or 28 vents. I have some longer runner intakes and the other carbs so it's just a matter of experimenting I guess. 2.0L Bus piston Web 86B portmatch intake and exhaust ports. 13lb flywheel Bursch SSI Car weighs 1965 lbs 205/50-15 Kumho V700 R tires. Thought of playing with spacers under the carbs to get more length and maybe spacer under the common length velocity stack. Looking for more torque down lower to pull harder exiting the apex of tight AX turns. Whose got the experience of really been there done that? great gains or don't bother. |
lapuwali |
May 18 2005, 04:40 PM
Post
#2
|
Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Andy's right. Long = low-end weighted power curve, short = top-end weighted power curve. In both cases, with all else equal, the area under the torque curve is the same, you're just moving the peak up and down the rev band.
Picture a typical dyno chart, with RPM rising left to right, and HP and torque rising bottom to top. Move the torque peak to the right (higher revs), and you move the HP peak UP as well as farther to the right. Make the intake tract longer (no other changes), and the torque peak moves left (better low-rev torque, but less HP at peak). Make it shorter, and the torque peak moves right (less torque at low-revs, but more HP at peak). Same thing happens with exhaust header lengths. |
Lo-Fi Version | Time is now: 1st June 2024 - 10:47 PM |
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 ... |