Author |
Message |
mmunoz Samba Member
Joined: December 16, 2020 Posts: 11 Location: MA
|
Posted: Tue May 17, 2022 6:58 am Post subject: SVDA Timing |
|
|
Good morning, trying to setup proper timing for my engine. It is a 1600DP with a BOSCH blue coil, a Pertronix SVDA electronic distributor (#PER-D186504) and a 34 PICT 3 carb. My pulley has 3 notches, which I believe are TDC, 7.5, and 10?
Valves at .006 at TDC then going CCW 180 for each valve. Distributor set a TDC static. Carb screws both set at all in then out 2.5 turns. Did not mess with the idle cam/screw.
Questions:
Am I correct so far? What should I be timing the distributor for with a timing gun? and at what RPM?
Any tips to get it running would be great, she is running with lack of power on 3rd and 4th gear, and exhaust is way too hot, although oil is cool.
Thanks |
|
Back to top |
|
|
carcrazed Samba Member
Joined: November 15, 2007 Posts: 957 Location: Ohio
|
Posted: Tue May 17, 2022 3:20 pm Post subject: Re: SVDA Timing |
|
|
Sounds like you are running too lean and/or the timing is retarded too much. You are on the right track. Advance the time a little more. Make sure you have your vacuum advance blocked off when tuning (if it has one). The timing should be about 7.5 btdc at idle. Rev the engine to about 2000 rpm and it should advance (can't remember the number off the top of my head). Next...turn your mixture screws out 1/2 turn at a time until the engine starts to load down. turn them in 1/2 turn in and that is it. Go from there. _________________ 1965 Herbie Replica. 1776cc dual Kads.
1961 Beetle 33,000 Original Miles
"Just When you think you are getting ahead, you're always wrong." |
|
Back to top |
|
|
67rustavenger Samba Member
Joined: February 24, 2015 Posts: 9770 Location: Oregon
|
Posted: Tue May 17, 2022 5:16 pm Post subject: Re: SVDA Timing |
|
|
Disconnect the dist. vacuum line from the carb and plug the carb nipple.
Start the engine let it warm up.
Using a timing light. Rev the engine until the dist advance stops advancing, should be around 3K RPM. Ideally set your timing between 28-30° advanced.
When the RPM drops back to idle. Read the timing again with the light. That's your new idle timing.
Reconnect the vacuum line to the carb.
After timing the engine. Now go after the carb tune as described in the post above. _________________ I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!
There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo! |
|
Back to top |
|
|
rcooled Samba Member
Joined: September 20, 2008 Posts: 2506 Location: Santa Cruz, CA
|
Posted: Tue May 17, 2022 7:28 pm Post subject: Re: SVDA Timing |
|
|
mmunoz wrote: |
Am I correct so far? |
Yes.
Here's how to properly adjust the 34PICT-3 carb: http://www.vw-resource.com/34pict3.html
There's another factor to consider here. 34PICT carbs all have a small hole in the throttle plate. Carbs that were originally paired with dual vacuum, dual advance (DVDA) distributors (timing at idle set after TDC) have a 5/32" hole, while carbs paired with single vacuum, dual advance (SVDA) distributors (timing at idle set before TDC) have a 1/8" hole.
If your carb has the larger 5/32" hole, it'll be more difficult to set the idle correctly when using an SVDA distributor, like that Pertronix. A common fix for this is to install a pop-rivet in the hole and punch out its center mandrel to reduce the size of the hole. _________________ '63 Ragtop (current)
'65 Ghia coupe (totaled)
'67 Ghia convertible (current)
'69.5 Ghia convertible and
'62, '63, '65, '69 Bugs (all long gone) |
|
Back to top |
|
|
mmunoz Samba Member
Joined: December 16, 2020 Posts: 11 Location: MA
|
Posted: Wed May 18, 2022 6:26 am Post subject: Re: SVDA Timing |
|
|
Thanks so much for the replies! I appreciate it. I am also going to try the pencil method to make sure TDC is correct with my assumption of the marks on the pulley. |
|
Back to top |
|
|
Cusser Samba Member
Joined: October 02, 2006 Posts: 31379 Location: Hot Arizona
|
Posted: Wed May 18, 2022 6:53 am Post subject: Re: SVDA Timing |
|
|
mmunoz wrote: |
I am also going to try the pencil method to make sure TDC is correct with my assumption of the marks on the pulley. |
NO, NO, NO !!!!
Use a plastic straw instead. Folks have broken off the eraser part of a pencil or the other end inside the cylinder, using this "test".
This "test" with a pencil needs to be retired forever, just like pulling off a battery cable to "test" for charging on an alternator-equipped vehicle..... _________________ 1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297 |
|
Back to top |
|
|
mmunoz Samba Member
Joined: December 16, 2020 Posts: 11 Location: MA
|
Posted: Wed May 18, 2022 9:02 am Post subject: Re: SVDA Timing |
|
|
Thanks for the info on the straw! Will do. |
|
Back to top |
|
|
mukluk Samba Member
Joined: October 18, 2012 Posts: 7028 Location: Clyde, TX
|
Posted: Wed May 18, 2022 9:12 am Post subject: Re: SVDA Timing |
|
|
Use your pulley marks to find TDC.
If you're not sure what your pulley marks are, pull the crankshaft pulley bolt out and look at where the slot for the woodruff key is located. This is always at 90° to a TDC. For TDC of 1&3 it will be 90° to the left (nine o'clock), and for TDC of 2&4 it will be 90° to the right (three o'clock).
Stop sticking items other than spark plugs into the spark plug holes, especially pencils.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9858590&highlight=#9858590 _________________ 1960 Ragtop w/Semaphores "Inga" |
|
Back to top |
|
|
mmunoz Samba Member
Joined: December 16, 2020 Posts: 11 Location: MA
|
Posted: Wed May 18, 2022 11:44 am Post subject: Re: SVDA Timing |
|
|
Thanks my pulley looks exactly like that but no dent dimple thing. |
|
Back to top |
|
|
mukluk Samba Member
Joined: October 18, 2012 Posts: 7028 Location: Clyde, TX
|
|
Back to top |
|
|
|