Carb question, need to dump little gas in carb just to get car started |
|
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. |
|
Carb question, need to dump little gas in carb just to get car started |
angerosa |
Apr 28 2013, 08:45 AM
Post
#1
|
Member Group: Members Posts: 334 Joined: 21-August 07 From: Reston, VA Member No.: 8,023 Region Association: MidAtlantic Region |
Seems that this year I need to put a little gas into the carb to get the car started initially. I have single Solex carb that no one seems to be able to identify. I'm sure some PO just pulled it off something that was sitting in a junkyard. Once I get car started and it warms up it idles OK but runs rough when you try to drive it. Timing is spot on. Recent (not too many miles ago) tune up with the help of some very knowledgeable 914world brethren. Let’s say it’s a given that there is nothing wrong with the engine. I have an idea of where to go next. I’ve had car for about 7 years. With only what I’ve told you here what’s your opinion?
|
Mike Bellis |
May 4 2013, 04:49 PM
Post
#2
|
Resident Electrician Group: Members Posts: 8,346 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None |
Now you're at the point where you find the achilles heal of that type of carb setup. The biggest challenge is tau. The effect of the long runners is tau or fuel that falls out of suspension and runs down the walls of the runner. VW solved the problem in the Bug with an exhaust tube running next to the intake runner. The extra heat helps keep the tau from forming.
The bucking could be either too much or too little fuel due to tau. Most likely to little fuel in suspension. As the fuel on the wall makes it to the combustion chamber, it is liquid and not aerated. This can make it run like it's lean while blowing excess fuel out the exhaust. You will not get a good burn with liquid gas. As far as tuning you will need to find jets for the carb and get a wide band AF meter or use the seat of your pants method. Bottom line, you will need to play with it but it may never be perfect. |
Lo-Fi Version | Time is now: 27th September 2024 - 01:14 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 ... |