What's your timing set at? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > What's your timing set at?

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineNEW ZJ Grand Cherokee Tube DoorsGibson WK HEMI 3" Catback - 5 Day Special!

Reply
Unread 07-11-2015, 05:40 PM   #1
ZombiePopper
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2015
Location: Pomona, Kansas
Posts: 120
What's your timing set at?

Have a question guys,
I checked at my 4.2 timing today (up to temp and vac advance plugged) and I'm dead nuts on 8*. (It's nuttered and team rushed.)
But after locking down my dizzy and plugging the vac adance back into the dizzy I double checked my timing again.
At idle (600-700rpm up to temp)
My timing mark on the balancer is past the timing scale on the timing cover (towards the passenger side of the engine).
If I increase the rpm's slightly the timing mark moves even further away.
So I plugged the vac advance again and checked timing again and it's still at 8*.
My question;
Is it normal on these 4.2's for the vacuum advance to kick in at idle?
Thanks

__________________
69Dodge Dart Swinger 5.9l mag swap
89YJ Wrangler 4.2
ZombiePopper is offline   Reply With Quote Quick reply to this message
Unread 07-11-2015, 06:18 PM   #2
Jeepsr4me
Registered User
 
Join Date: Dec 2004
Posts: 7,485
yes,,,,, Thats why you have to take the hose off to set timing.
Jeepsr4me is offline   Reply With Quote Quick reply to this message
Unread 07-11-2015, 06:23 PM   #3
ZombiePopper
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2015
Location: Pomona, Kansas
Posts: 120
Ok thanks Jeeps4me, I just wanted to verify that it should be advanced that far with vac advance plugged in.
__________________
69Dodge Dart Swinger 5.9l mag swap
89YJ Wrangler 4.2
ZombiePopper is offline   Reply With Quote Quick reply to this message
Unread 07-11-2015, 08:00 PM   #4
timatoe
Web Wheeler
 
timatoe's Avatar
1990 YJ Wrangler 
 
Join Date: Aug 2006
Location: Grass Valley California
Posts: 14,321
Yeah, your timing should be checked and set at curb idle with no vac advance. I'm sure elevation will play a bit of a part, but mine set like yours is @ 13* BTDC, that's where it seems to run the best.
__________________
Quote:
Originally Posted by George Orwell
We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm.
timatoe is offline   Reply With Quote Quick reply to this message
Unread 07-11-2015, 09:17 PM   #5
ZombiePopper
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2015
Location: Pomona, Kansas
Posts: 120
Good point Tim, I'm going to play with the timing a bit, a couple degrees +/- to find the "sweet spot"
__________________
69Dodge Dart Swinger 5.9l mag swap
89YJ Wrangler 4.2
ZombiePopper is offline   Reply With Quote Quick reply to this message
Unread 07-12-2015, 05:46 AM   #6
Mike Romain
Registered User
1986 CJ7 
 
Join Date: Nov 2007
Location: Off the Grid in Chester Grant, Nova Scotia, Canada
Posts: 16,882
Well.... I personally don't like my advance to kick in until I give it gas. Mine (nuttered) also won't pass the emissions sniffer if it is advanced all to crap at idle. Lots of folks like to argue with me and say I can't be right, but I think I get a Way better punch off the line on ported vacuum. When I tromp the go pedal, my advance instantly jumps up this way and it will peel my 33's off a start.
When at speed, it makes no difference, ported and manifold vacuum are the same, but off the line, well... I always recommend folks try both ways. Ported is old school muscle car style. It will burble and pop coming down a hill in gear too.
Stock, the ported distributor nipple is the one on the valve cover side of the BBD.
__________________
Mike
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
Mike Romain is online now   Reply With Quote Quick reply to this message
Unread 07-12-2015, 10:25 AM   #7
ZombiePopper
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2015
Location: Pomona, Kansas
Posts: 120
Actually I would tend to agree with you Mike.
Whenever I set-up a v8 I usually always adjust/replace my springs/weights so at idle my advance is minimal until I hit the go-pedal.
But that's with my v8's, I was surprised to find that this 4.2 was advanced so far at idle (with vac advance hooked-up), but I didn't know if it was typical or if folks replace the weights/springs to reduce the amount of advance at idle?
I'm running a 2g carb so my ported vac is straight from the carb so I may play with a couple other vac ports to see if I can reduce the amount if advance at idle though...
__________________
69Dodge Dart Swinger 5.9l mag swap
89YJ Wrangler 4.2
ZombiePopper is offline   Reply With Quote Quick reply to this message
Unread 07-12-2015, 11:14 AM   #8
Mike Romain
Registered User
1986 CJ7 
 
Join Date: Nov 2007
Location: Off the Grid in Chester Grant, Nova Scotia, Canada
Posts: 16,882
Quote:
Originally Posted by ZombiePopper View Post
Actually I would tend to agree with you Mike.
Whenever I set-up a v8 I usually always adjust/replace my springs/weights so at idle my advance is minimal until I hit the go-pedal.
But that's with my v8's, I was surprised to find that this 4.2 was advanced so far at idle (with vac advance hooked-up), but I didn't know if it was typical or if folks replace the weights/springs to reduce the amount of advance at idle?
I'm running a 2g carb so my ported vac is straight from the carb so I may play with a couple other vac ports to see if I can reduce the amount if advance at idle though...
Stock, the 4.2 has an ECU controlling the timing advance. That's why it sets at 1600 rpm, not at idle. Nuttered takes the engine back to pre 82 tuning with the ICM in total control.
The ported vacuum should be 0 at idle and it jumps up when the throttle plate opens.
One old school FSM says it uses manifold vacuum on the timing via a CTO switch so the idle bumps up if you get hotter than 220F to help the fan cool it at the higher idle, otherwise it uses ported.
They do make a different distributor with a wider advance range for the pre- ECU engines, you can order one for say a 1978. They run about $65.00 at Napa. You can also file the slots on yours. Look up posts by Jeephammer on that.
That said, I ran my stock distributor, nuttered for about 10 years before it wore out and I ordered the 78 one to replace it. I really couldn't tell the difference to be honest. But then it isn't a race engine either. :-)
__________________
Mike
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
Mike Romain is online now   Reply With Quote Quick reply to this message
Unread 07-12-2015, 08:15 PM   #9
ZombiePopper
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2015
Location: Pomona, Kansas
Posts: 120
Great info Mike
I'll do some searching on jeephammer and check my various vac ports.
__________________
69Dodge Dart Swinger 5.9l mag swap
89YJ Wrangler 4.2
ZombiePopper is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.