timing problems 350 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-26-2010, 12:26 PM
Registered User
 
Join Date: Sep 2010
Location: oklahoma
Posts: 37
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
timing problems 350

i have a timing problem with my chevy 350 small block quadrajet carb headers hei distributor new plug wires new spark plugs

ok my problem is my motor will not run smooth when it is time 8 degrees before top dead center its 99 percent stock except headers it lugs when i put it in gear and if i try to put it at 8 degrees it has no power but at say 16 it has a little increase in power but not what it should and runs great but its 16 degrees before tdc?? and wont run smooth any lower i beleive a 350 calls for 8 btdc but it only runs at 12 any lower nothing

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-26-2010, 01:32 PM
Greg T's Avatar
www.krusinklassics.net
 
Last photo:
Join Date: Jul 2007
Location: Escanaba, MI.
Age: 61
Posts: 1,160
Wiki Edits: 0

Thanks: 21
Thanked 41 Times in 32 Posts
Limit the amount of travel in the mechanical advance weights to about 18* and set the initial at 18* with the vac advance unplugged and the idle at about 650 rpm. Also, use some lighter springs on the mech advance to bring it all in sooner. Then, plug the vac advance into full manifold vac. Should run like a scared rabbit.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-26-2010, 01:49 PM
Registered User
 
Join Date: Sep 2010
Location: oklahoma
Posts: 37
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ok i will try that tomorow does orielys or napa sell a kit for it and what kind should i get?
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-26-2010, 02:30 PM
Custom10's Avatar
my KARMA ran over my DOGMA
 

Last journal entry: SS
Last photo:
Join Date: May 2009
Location: Saskatchewan, Canada
Age: 50
Posts: 1,101
Wiki Edits: 0

Thanks: 18
Thanked 33 Times in 28 Posts
A good kit that may help you:

http://www.cranecams.com/pdf/Page607.pdf

One thing that it will not address is the mechanical limit, this you will need to set with some type of travel stop on the rotor plate but I am not sure exacly which HEI you have.

The vacuum advance will need to be limited as well, the plate is in the kit. If you go 18 base, + 18 mech as gregT said, the vaccum adv should be limited to 12, this will require that you set the limiter plate near the last notch on the big side. That would bring your total timing to 48.

You can start with say one heavy spring and one medium/light spring and see if you can get your base + mech to be all in at about 3000rpm with the vacuum adv can disconnected. At idle with the vacuum can connect to manifold vac you should have just over 30 deg BTDC if the mechanical is not coming in as well which is something you want to avoid, the springs will determine this and having one heavy one in there should keep it out below 800-900 rpm.

2 more of my cents
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-26-2010, 02:38 PM
Registered User
 
Join Date: Sep 2010
Location: Tn
Posts: 13
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Chevy makes 3 dist's with 3 different timing setting. Depending on which dist you have maked the difference in initial timing. I do not like to curve a stock motor, I curve one to match an after market camshaft and remove the vacume all together so it always runs at the max curve in the powerband of the camshaft. If you do not have an after market camshft in it, using both the soft springs can still cause it to still bounce. May need a med on one side and soft on the other if you choose to try a kit.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-26-2010, 02:52 PM
Registered User
 
Join Date: Sep 2010
Location: oklahoma
Posts: 37
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
mono what ur saying is since my motor has no aftermarket cam in it would u recomend just buying a new hei dist?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 09-26-2010, 03:36 PM
Registered User
 
Join Date: Sep 2010
Location: Tn
Posts: 13
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
No, there maybe other issues. Have you checked the mark on the balancer? I have seen them slip and be off big time, so 8 maybe 16 or 5 etc.. in reality. Have you put a vacuum gage on the motor to see what the vacuume is while changing the timing? Have you checked the timing at 3k rpm's? If you have is it in the ball park of what it should be(36)? If not you will have to make a new mark on the balancer which is a job but can be done. How did you adjust the carb? Headers usually run a little diffenrent on adjustment screws then stock manifolds, usually a round and a half more. If you have the floats set on the carb. screw the adj screw in until the motor missing slightly back it out 2 to 3 and half rounds for headers and 1.5 for stock manifolds, start at 2.5 Do both sides the same way. Of course if you screw the screws in and there is no change in the motor that is an issue as well. I find it hard to beleive timing would cause an miss, maybe kill the motor or make it slugish but not miss. Have you checked the plugs? On the porcelain portion of the plug what color is it? It should be paper bag brown if it is black it maybe because you did not back the screws out enough. Drive it for a day or two and see if they clean up. Also check the heat range on them while you at it. Also take a can of wd40 and spray the intake and around carb while motor is running, if it dies then you have a leak. I also had a fuel pump one time drove me crazy because it caused the motor to miss at idle, like to have never found it. Good luck
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 09-26-2010, 03:49 PM
Registered User
 
Join Date: Sep 2010
Location: Tn
Posts: 13
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Sorry on the miss, I am reading 2 threads and the other is missing.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 09-28-2010, 08:04 PM
Registered User
 
Join Date: Sep 2010
Location: oklahoma
Posts: 37
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
alright my 350 is now at 8 * btdc now the problem is while im in park i get good throttle response but when i put it in gear if i tap the gas instead of responding like a motor should it almost dies and lugs out and another thing if my vacumn advance is hooked up while idleing it brings my timing mark up but if i take it off it shows 8* any ideals im thinking carb on both problems like i said before i have a quadrajet not sure of cfm or anything else just electric choke and 4 barrel all i know about it tomorow im going to place the motor on tdc and take on the left side valve covers and see if my rocker arm is flat and to adjust my valves thats the only ideals i have about the lack of response while in gear
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last 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 for yourself.
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.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Chevy 350 with 292 cam Total timing ChevyMopar318250 Engine 59 10-13-2010 08:45 AM
chevy 350 timing problems Wildwestshow Engine 5 09-24-2010 05:54 PM
Need Help FAST!!!!!!!!!! millertime85 Engine 14 06-25-2008 08:01 PM
chevy 350 with 272/282 dur cam ignition timing ?? fast68 Engine 9 11-14-2005 01:34 PM


All times are GMT -6. The time now is 01:37 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.