383 stroker timing - Team Camaro Tech
Team Camaro Tech join team camaro
 Ground Up Restorations

Official Sponsor of Team Camaro



Registered users (free) do not see these large ads

Second Generation 1970-1981


Reply
 
LinkBack Thread Tools
Display Modes
Old Mar 9th, 20, 04:19 PM   #1 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Question 383 stroker timing

Hello....This maybe a late response but FWIW,.. I have same issue with my 383 stroker, which I didnt build..
To get it to run good, the timing has to be out of spec... and as many would say, set it up to run good and forget 'WAY OFF' timing marks and leave it...!
I used an endoscope to check TDC #1 piston and valves closed, its spot on '0'deg timing tab...So at idle initial timing is @28deg, if Dizzy is standard(i dont know if its been altered) at @22deg ..which makes total timing @50deg @4000rpm..
I was told it has a 268cam, which is a common streetable for SBC.. L31 Vortec heads roller rocks 1.5.. not overkill at all.


Engine always starts first go, idles, drives, powers and cruises great, no pre detonation, but pings slightly under load in 6th gear only if im heavy on pedal...it has 3:42 rear gears.

before this, I checked timing from a different mark ( was yellow painted on Tab @17deg BTDC.? ) and timing read @14deg initial, and @36deg total at 3500rpm..

This mark was not correct, to TDC, but the result is the same, as engine still runs fine..! the same..(dont know why the yellow paint mark was there.)



The MSD dizzy cap with HEI is horizontal to firewall and #1 and #8 plugs on cap are horizontal as well behind air cleaner..


I have never found an explanation yet, online...?? most comments dont seem to relate to this problem...?
I love driving my Camaro.... this just baffles me..?


this post was in another topic.



cheers.. Den.
denholden is offline   Reply With Quote Quick reply to this message
Old Mar 9th, 20, 08:09 PM   #2 (permalink)
DjD
Retired
 
DjD's Avatar
 
Join Date: Apr 1999
Location: Fortuna, CA
Posts: 26,553
Garage
Re: 383 stroker timing

Most strokers dial in around 34 degs total mechanical advance. Use a timing light, disconnect the vacuum advance and rev that puppy and find your total timing. It's possible to see 50 degs combined at part throttle with vacuum advance. Other things like octane and aluminum heads could allow you to run more total advance without pinging...
__________________
...Dennis

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


"Don't take life so serious, you won't get out alive..."
DjD is offline   Reply With Quote Quick reply to this message
Old Mar 10th, 20, 05:02 PM   #3 (permalink)
Moderator
 
DOUG G's Avatar
 
Join Date: Mar 1999
Location: Maryland, USA
Posts: 19,693
Garage
Send a message via MSN to DOUG G
Re: 383 stroker timing

Lots of things go into what your motor WANTS....give it what it wants.


As for the pinging in 6th...load on the motor. Need to reduce timing.
__________________
68 Camaro~LSx ~all motor
1.54 60'--6.95 @ 98.45 660'--10.96 @ 121.53

Last edited by DOUG G; Mar 10th, 20 at 05:18 PM.
DOUG G is offline   Reply With Quote Quick reply to this message
Old Mar 10th, 20, 05:12 PM   #4 (permalink)
Tech Team
 
Join Date: May 2006
Location: Ringgold, GA
Posts: 56
Re: 383 stroker timing

When at TDC on #1, did you pull the distributor cap, verify the rotor is pointing directly at #1 post? You can use a magic marker on the base of the distributor to make a reference mark.
__________________
Corky
CorkyE is offline   Reply With Quote Quick reply to this message
Old Mar 15th, 20, 10:53 PM   #5 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Re: 383 stroker timing

Corky, That was my next step.. I checked and dizzy rotor was slightly closer to #8 plug..
which explains the early timing light flash at about 30deg BTDC at idle... I retarded it more, and it still ran ok and brought the timing closer at about 24deg at idle..
Now I know I have room to retard Dizzy ( and reduce pinning in 6th gear )while advancing the timing flash and keep it running good while I test drive it.
Cheers to all the advice guys.
denholden is offline   Reply With Quote Quick reply to this message
Old Mar 16th, 20, 02:22 AM   #6 (permalink)
Gold Lifetime Member
 
Join Date: Mar 2016
Location: Austin, Texas
Posts: 1,289
Garage
Re: 383 stroker timing

I had a problem with my timing light showing the timing was way off when it ran correctly. I have an Multi-spark Digital Capacitive Discharge ignition. I purchased a timing light; MSD Inductive Timing light P/N 8992 for Muilti-Spark systems and it read correctly.

Brett......
__________________
Rockets Up In 2020! Inaugural Launch Date: 9/16/2020 - Vandenberg AFB Pad SLC-2W

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1969 Code X-66 SS 396 - RS Conversion - TKO600 - 3.73 Posi - Paint Code 71-LeMans Blue
Brettallen59 is offline   Reply With Quote Quick reply to this message
Old Mar 21st, 20, 05:27 PM   #7 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Re: 383 stroker timing

I believe ATM my idle timing is at about 30-32 deg BTDC 2-2.25 inches from "0" Tab TDC and runs good..?? starts first go, and has a little lobe with mild cam, sounds good.
denholden is offline   Reply With Quote Quick reply to this message
Old Mar 21st, 20, 07:42 PM   #8 (permalink)
Gold Lifetime Member
 
bill3337's Avatar
 
Join Date: May 2008
Location: Victoria, BC Canada
Posts: 365
Re: 383 stroker timing

I don't get it. At that much timing at idle (if everything is reading correctly) I would think it would kick back so hard it wouldn't start, and when you shut if off I would expect it to run on (dieseling). Something must be wrong there. I have a 602 hp 383 stroker and even at 22 degrees initial and 36 total it wants to kick back sometimes on starting and run on occassionally when I shut it down.
bill3337 is offline   Reply With Quote Quick reply to this message
Old Mar 21st, 20, 10:34 PM   #9 (permalink)
Gold Lifetime Member
 
Join Date: Mar 2018
Location: Nashville TN
Posts: 629
Re: 383 stroker timing

Quote:
Originally Posted by denholden View Post
I believe ATM my idle timing is at about 30-32 deg BTDC 2-2.25 inches from "0" Tab TDC and runs good..?? starts first go, and has a little lobe with mild cam, sounds good.
You're supposed to check initial timing with the vacuum advance line plugged.

It sounds like you're problem is too much vacuum advance. You probably get 14-16 degrees advance from vacuum; it should be 10-14.

You'll need a mechanical stop to adjust it.

Vortec heads typically run best with 32 degrees total mechanical advance. Add 12-14 vacuum advance and your total will be 44-46 degrees.
__________________
68 Camaro convertible, 6.0 LQ4 with LS3 heads, Vintage Air, 750 street demon carb, eddy perf rpm, GM hot cam, Hooker headers, 4L80e, 12 bolt, 3.55 gears
NashvilleCat is offline   Reply With Quote Quick reply to this message
Old Mar 22nd, 20, 02:05 AM   #10 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Re: 383 stroker timing

Hi, The dizzy has no vacuum at idle... its connected to ported, so I presumed it doesn't matter to the timing at idle ..?? I left it connected...
disconnecting that vacuum line and blocking it will do nothing if there is no vacuum at idle on that ported line, that's my take on it.? Other carby full vacuum ports are used or blocked off.
This is how it was originally set up when I bought it.???
It is strange...
denholden is offline   Reply With Quote Quick reply to this message
Old Mar 22nd, 20, 02:54 AM   #11 (permalink)
Gold Lifetime Member
 
Join Date: Mar 2018
Location: Nashville TN
Posts: 629
Re: 383 stroker timing

Quote:
Originally Posted by denholden View Post
Hi, The dizzy has no vacuum at idle... its connected to ported, so I presumed it doesn't matter to the timing at idle ..?? I left it connected...
disconnecting that vacuum line and blocking it will do nothing if there is no vacuum at idle on that ported line, that's my take on it.? Other carby full vacuum ports are used or blocked off.
This is how it was originally set up when I bought it.???
It is strange...
Read this, connecting to ported vacuum is for emission controlled vehicles only:

http://www.camaros.org/pdf/timing101.pdf
__________________
68 Camaro convertible, 6.0 LQ4 with LS3 heads, Vintage Air, 750 street demon carb, eddy perf rpm, GM hot cam, Hooker headers, 4L80e, 12 bolt, 3.55 gears
NashvilleCat is offline   Reply With Quote Quick reply to this message
Old Mar 22nd, 20, 03:38 AM   #12 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Re: 383 stroker timing

Hi, Thanks for the link Ncat, I had my suspicions on 'ported vacuum' and read the topic... The reason I didnt change it was I looked up the MSD specs and it said to connect to 'ported' ... thats why I left it as is..
So maybe I May change Dizzy to Full vacuum, and re-set at idle, and check timing again at idle..??
As I said earlier, this is how it was set up when I bought it. I thought the guy knew his stuff as he has many classics and race cars.. maybe he had a reason for it..????
denholden is offline   Reply With Quote Quick reply to this message
Old Mar 22nd, 20, 09:26 AM   #13 (permalink)
Gold Lifetime Member
 
bill3337's Avatar
 
Join Date: May 2008
Location: Victoria, BC Canada
Posts: 365
Re: 383 stroker timing

The timing may have been set correctly with the vacuum line disconnected and the port blocked off. (Be sure to block the port, not just disconnect). Check your timing with it disconnected and blocked and see what you've got. Even if you were into the ported vacuum, I suspect you will find your timing will read lower.
bill3337 is offline   Reply With Quote Quick reply to this message
Old Mar 22nd, 20, 11:19 PM   #14 (permalink)
Tech Team
 
Join Date: Jan 2019
Posts: 31
Re: 383 stroker timing

Hi Bill,NCat and followers...
Ok,Update... tried different applications, disconnected ported vacuum line from Dizzy and blocked it..(no vacuum) idle timing at @30-32 deg. started and idled ok... Retarded Dizzy to get to 16-20deg at idle, but really struggling to idle, so adjusted idle.. Then connected full vacuum line to Dizzy and naturally idle increased a bit as well as a noticeable rattle from Dizzy..which I didn't like...?? and timing went back to about 30deg..Rattle stops when I disconnected vacuum line from dizzy and idle drops again..
So I'm playing safe guys... Ive put it back to ported as it was, adjusted idle and retarded dizzy so its idleing at about 24deg.. took it for a test drive and is running ok, no pinging or detonation and starts first go.. I could even go to 26deg and it could be better..??
So I will leave it for now, I think it is what it is for my stroker.

FWIW the MSD HEI dizzy I have is spec'd at 21 deg Mechanical advance (if standard)..
so 21 + 24 gives 45 total timing.. so it is what it is.?

Thanks for all the input readers, I hope it assists other readers who are stumped.?
But if thats what it must be, lets go with it. cheers!!
denholden 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 Team Camaro Tech 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 email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.

Email Address:
Location
Location
First Name
Rather than just Hot69, gotta real name?

Log-in


Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


» Recent Discussions
New emerging...
Mar 1st, 19 07:00 AM
by Gbauer
Last post by Mkelcy
Today 10:00 PM
9 Replies, 87 Views
Newbie seeking wisdom
Today 09:29 PM
by Cc0599
Last post by Cc0599
Today 09:40 PM
1 Replies, 18 Views
Off topic forum
Today 04:05 AM
by dhutton
Last post by slazisme
Today 08:17 PM
33 Replies, 530 Views
Looking for Some...
Today 12:21 PM
Last post by jimsl78
Today 07:58 PM
3 Replies, 126 Views
67 RS Headlights Doors...
Today 07:37 PM
Last post by 1967CamaroRSSS
Today 07:37 PM
0 Replies, 52 Views
5 years of work to get...
May 27th, 20 01:39 PM
Last post by 97 CAIVIAROSS
Today 06:57 PM
8 Replies, 388 Views
Flushing Coolant...
Today 08:30 AM
Last post by DjD
Today 06:57 PM
5 Replies, 144 Views
Installing roof rail...
Today 12:06 PM
Last post by Sauron67MM
Today 06:36 PM
3 Replies, 128 Views
Kick Panel Speakers and...
Yesterday 07:28 PM
Last post by Nantooch
Today 05:17 PM
5 Replies, 164 Views
tire valve stem lenght...
Yesterday 07:56 AM
Last post by Nantooch
Today 05:09 PM
1 Replies, 172 Views
Powered by vBadvanced CMPS v3.2.3

All times are GMT -7. The time now is 10:03 PM.



Camaros.net - © 2009 AutoForums.com
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.