 Bouncy Tach, ...I tried the fix |
|
|
|
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. |
|
|
| yeahmag |
 Apr 28 2010, 11:04 AM
Post
#1
|
|
Advanced Member  Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California 
 |
So once I got my 2056cc built the tach could no longer keep up and just flailed around worthlessly... Especially when running an autocross. So I finally got around to trying the 2200uF trick and now it's over damped... Sigh. Maybe I'll try a different variant of capacitor and see what happens.
Anybody else have a recommended type of capacitor for the application: http://en.wikipedia.org/wiki/Types_of_capacitor |
   |
 
|
  |
Replies
| JamesM |
Apr 28 2010, 11:53 AM
Post
#2
|
|
Senior Member Group: Members Posts: 1,915 Joined: 6-April 06 From: Kearns, UT Member No.: 5,834 Region Association: Intermountain Region |
QUOTE(yeahmag @ Apr 28 2010, 09:04 AM)  So once I got my 2056cc built the tach could no longer keep up and just flailed around worthlessly... Especially when running an autocross. So I finally got around to trying the 2200uF trick and now it's over damped... Sigh. Maybe I'll try a different variant of capacitor and see what happens. Anybody else have a recommended type of capacitor for the application: http://en.wikipedia.org/wiki/Types_of_capacitor I used a 2200uf cap that i pulled off of an old motherboard i had laying around, there are usually a bunch of them surounding the CPU. Works nice and smooth now however i also modded my tach to take the lower voltage output from a spark box. |
 |
|
| yeahmag |
Apr 28 2010, 11:58 AM
Post
#3
|
|
Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California
|
QUOTE(JamesM @ Apr 28 2010, 10:53 AM) QUOTE(yeahmag @ Apr 28 2010, 09:04 AM) So once I got my 2056cc built the tach could no longer keep up and just flailed around worthlessly... Especially when running an autocross. So I finally got around to trying the 2200uF trick and now it's over damped... Sigh. Maybe I'll try a different variant of capacitor and see what happens. Anybody else have a recommended type of capacitor for the application: http://en.wikipedia.org/wiki/Types_of_capacitor I used a 2200uf cap that i pulled off of an old motherboard i had laying around, there are usually a bunch of them surounding the CPU. Works nice and smooth now however i also modded my tach to take the lower voltage output from a spark box. I'm getting the feed off my Mallory 6AL. How or what mod's did you make? |
|
|
|
| JamesM |
May 11 2010, 11:22 AM
Post
#4
|
|
Senior Member Group: Members Posts: 1,915 Joined: 6-April 06 From: Kearns, UT Member No.: 5,834 Region Association: Intermountain Region |
I am using the 6AL as well. Check out the pic that Dave Hunt posted, that is the modification i am talking about. The signal coming from the 6AL is not as strong as it would be off the coil. Jumper that resistor and see if it helps. With the 6AL, the resistor bypassed, and the 2200uf cap across the windings, mine is nice and smooth.
-James QUOTE(yeahmag @ Apr 28 2010, 09:58 AM) QUOTE(JamesM @ Apr 28 2010, 10:53 AM) QUOTE(yeahmag @ Apr 28 2010, 09:04 AM) So once I got my 2056cc built the tach could no longer keep up and just flailed around worthlessly... Especially when running an autocross. So I finally got around to trying the 2200uF trick and now it's over damped... Sigh. Maybe I'll try a different variant of capacitor and see what happens. Anybody else have a recommended type of capacitor for the application: http://en.wikipedia.org/wiki/Types_of_capacitor I used a 2200uf cap that i pulled off of an old motherboard i had laying around, there are usually a bunch of them surounding the CPU. Works nice and smooth now however i also modded my tach to take the lower voltage output from a spark box. I'm getting the feed off my Mallory 6AL. How or what mod's did you make? |
|
|
|
Posts in this topic
yeahmag Bouncy Tach Apr 28 2010, 11:04 AM
Dr Evil Maybe halving the farads will help? Apr 28 2010, 11:13 AM yeahmag My EE friend thought that changing the type is pro... Apr 28 2010, 11:17 AM Dr Evil Where did you get the info on the capacitor? I tho... Apr 28 2010, 11:24 AM yeahmag It's just what the EE stock room on campus had... Apr 28 2010, 11:27 AM Dr Evil IIRC, the 2200uF was the one used to convert to a ... Apr 28 2010, 11:47 AM Vacca Rabite Mine also bounces in the 2056. I just figured it ... Apr 28 2010, 11:52 AM
tat2dphreak
:agree: same here
more aggressive I drive, more ... Apr 28 2010, 11:54 AM DNHunt I'm not sure if this helps (free advice, take ... Apr 28 2010, 01:02 PM Dr Evil Jumping a resistor makes some sense as well. It is... Apr 28 2010, 01:04 PM DNHunt Magic smoke is still contained (knock on wood). Apr 28 2010, 01:06 PM BIGKAT_83 The Tach is dampend with a pin coming off of the m... Apr 28 2010, 01:52 PM Frost My tach justo bounce then i start the car one day ... Apr 28 2010, 04:32 PM D1A3 Had a similar problem and found the connection on ... Apr 28 2010, 04:47 PM sgetsiv Remember that capacitors add in parallel. You can ... May 3 2010, 11:15 PM yeahmag After my PCA event on Sunday I noticed it's re... May 4 2010, 09:43 AM ClayPerrine Just send it to North Hollywood or Palo Alto and t... May 4 2010, 11:07 AM yeahmag Thanks, but with the Mallory 6AL doing the rev lim... May 4 2010, 11:16 AM Dr Evil There are variable capacitors. You could mount one... May 4 2010, 03:59 PM yeahmag Holy Crap! I was just making that up! I ha... May 4 2010, 04:12 PM Dr Evil That was part of the tuning mechanism of old schoo... May 4 2010, 10:24 PM sgetsiv If you are running carbs then...
I cured my bounc... May 10 2010, 11:48 PM Spoke The right capacitor is not an exact science. What ... May 11 2010, 07:40 AM yeahmag I'm guessing some of the reason for my tach ne... May 11 2010, 08:23 AM
yeahmag Will do. Might pull it back out of the dash tonigh... May 11 2010, 11:24 AM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 1st June 2024 - 03:02 PM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.