New Start up...350 efi timing help?? - 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 11-28-2012, 03:24 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
New Start up...350 efi timing help??

I have a 5.7 350 vortec .30 over
comp cams 08-300-8 (grind cs 262h-r12)
duration at .050 206(intake) and 210(exhaust)

I have gotten the motor installed back in the truck.

Long story short... I have removed and re-installed the distributor many many times now and just can't seem to get this thing timed right.

I have been too far advanced and to far retarded.

Just can't seem to set this thing up.. used a tdc stop a few times for tdc.

Also had an old timer come over to help and he helped me set it up just my feeling the cylinder pressure with his thumb. Still didn't work.

Any help appreciated. I'm stuck!

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 11-28-2012, 03:38 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
That is a 98 by the way.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 11-28-2012, 03:47 PM
Registered User
 
Join Date: Apr 2007
Posts: 9,599
Wiki Edits: 0

Thanks: 17
Thanked 222 Times in 179 Posts
Quote:
Originally Posted by abbazabba View Post
I have a 5.7 350 vortec .30 over
comp cams 08-300-8 (grind cs 262h-r12)
duration at .050 206(intake) and 210(exhaust)

I have gotten the motor installed back in the truck.

Long story short... I have removed and re-installed the distributor many many times now and just can't seem to get this thing timed right.

I have been too far advanced and to far retarded.

Just can't seem to set this thing up.. used a tdc stop a few times for tdc.

Also had an old timer come over to help and he helped me set it up just my feeling the cylinder pressure with his thumb. Still didn't work.

Any help appreciated. I'm stuck!
Assuming there are no other faults and with a Vortec there are many places where this can go wrong, the distributor needs to be set up with zero advance. The computer will establish all advance including the base setting.

The front timing cover has a sensor that looks for the crankshaft number 1 position. You need to time the damper to this sensor first.

The SBC times the cam to the number 6 cylinder when the pip marks on the cam and crank gear face each other. One crank rotation from that point which puts both marks in the 12 O'clock position then is set to number one cylinder.

All of this in the above paragraphs has to be coordinated; is it?

Bogie
Reply With Quote Quick reply to this message
The Following User Says Thank You to BogiesAnnex1 For This Useful Post:
abbazabba (11-28-2012)
 
  #4 (permalink)  
Old 11-28-2012, 04:02 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
No

How do I time the damper to the sensor? (Crank position sensor right?)

----"The SBC times the cam to the number 6 cylinder when the pip marks on the cam and crank gear face each other. One crank rotation from that point which puts both marks in the 12 O'clock position then is set to number one cylinder."----

Not sure about this one. I set the timing marks on the crank and cam gear so they were pointing directly at each other. I obviously can't see the gears any longer to verify what you are saying.

Thank you for your help!
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 11-28-2012, 04:16 PM
Registered User
 
Join Date: Feb 2012
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
On my 96 there was a punch mark on the block to line up the damper mark. Very hard to see. Had to take the rad shroud off and with finger in the #1 hole bump motor over till marks line up. Stab the dist. Then you need some one with a hand held capable of setting timing, but motor should run fine until you check timing.

Don
Reply With Quote Quick reply to this message
The Following User Says Thank You to dstinch For This Useful Post:
abbazabba (11-28-2012)
  #6 (permalink)  
Old 11-28-2012, 04:21 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
So a mark on block and the line on balancer? I will look for that.

Thanks
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 11-28-2012, 05:31 PM
Registered User
 
Join Date: Apr 2007
Posts: 9,599
Wiki Edits: 0

Thanks: 17
Thanked 222 Times in 179 Posts
Quote:
Originally Posted by abbazabba View Post
No

How do I time the damper to the sensor? (Crank position sensor right?)

----"The SBC times the cam to the number 6 cylinder when the pip marks on the cam and crank gear face each other. One crank rotation from that point which puts both marks in the 12 O'clock position then is set to number one cylinder."----

Not sure about this one. I set the timing marks on the crank and cam gear so they were pointing directly at each other. I obviously can't see the gears any longer to verify what you are saying.

Thank you for your help!
If they were still pointing at each other when you put the distributor in, and you aligned the the rotor to number one, then your timing is 180 degrees off as the cam was left set aligned to number 6 at TDC.

I know this can be confusing, one of GM's little intellectual gifts to the mechanics of the world.

Probably the quickest way to find out where it really is would be to remove the drivers side rocker cover so you can see the valve action on number 1. Put a wrench on the damper bolt and turn the engine over in the normal direction (clockwise when standing in front of the vehicle) watching the valve action. When both valves are closed and the piston is at TDC the timing marks should be aligning to zero (the cylinder is ready to fire), then check to see where the rotor is. If not pointing at number one make whatever the correction is (rotate the housing or remove and realign the distributor to get the proper rotor to cylinder alignment.

Bogie
Reply With Quote Quick reply to this message
The Following User Says Thank You to BogiesAnnex1 For This Useful Post:
abbazabba (11-28-2012)
  #8 (permalink)  
Old 11-28-2012, 05:47 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
Okay sounds like I didn't have tdc lined properly.

Would my motor run if it was 180 off?
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 11-28-2012, 05:49 PM
Registered User
 
Join Date: Apr 2007
Posts: 9,599
Wiki Edits: 0

Thanks: 17
Thanked 222 Times in 179 Posts
Quote:
Originally Posted by abbazabba View Post
Okay sounds like I didn't have tdc lined properly.

Would my motor run if it was 180 off?
No, but it will backfire and stumble around a lot.

Bogie
Reply With Quote Quick reply to this message
The Following User Says Thank You to BogiesAnnex1 For This Useful Post:
abbazabba (11-28-2012)
  #10 (permalink)  
Old 11-28-2012, 05:53 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
I will get to it first thing in the morning. Let you know what comes of it.

Thanks for the info.. I have hope again.

I will keep ya posted.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 11-30-2012, 02:11 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
Well....

So I did all of the above with no success.

Took my valve cover off(which was a total pain in the rear) gotta love those new vehicles.

Verified that tdc is lining up with balancer markings as well as valve position.. also looked in cylinder with mirror and I can see the piston.

pulled dizzy cap and sure enough my pointer is on the number one plug.

Soooo... im stuck again.

Any help would be wonderful.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 11-30-2012, 03:37 PM
Registered User
 
Last photo:
Join Date: Jul 2004
Location: At Speed
Age: 54
Posts: 2,001
Wiki Edits: 0

Thanks: 44
Thanked 205 Times in 181 Posts
The distributor only directs the spark and outputs the camshaft position, the crank position and hence timing are accomplished by the crank sensor in the timing cover.
What does it do when you try to start it?
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 11-30-2012, 05:07 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
I have a 5.7 350 vortec .30 over
comp cams 08-300-8 (grind cs 262h-r12)
duration at .050 206(intake) and 210(exhaust)

First ever turn of the key in the truck it started and ran.

Immediately it was off.

The idle seemed way low. about 500 rpm if i let it fall it would die.

The engine seemed sluggish not firing right.

I have reset the distributor many times and have had it hard to start or just crank crank crank. Both.

Has started several times during distributor re-positioning.


Yes I will test the crank sensor.


A local shop owner says you absolutely have to use a computer to set the timing on these?

Any thoughts on that? Software to buy?

I'm tempted to fork over some dough and get this done at the shop.



Thanks for the help.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 11-30-2012, 05:45 PM
Registered User
 
Join Date: Apr 2007
Posts: 9,599
Wiki Edits: 0

Thanks: 17
Thanked 222 Times in 179 Posts
Quote:
Originally Posted by abbazabba View Post
I have a 5.7 350 vortec .30 over
comp cams 08-300-8 (grind cs 262h-r12)
duration at .050 206(intake) and 210(exhaust)

First ever turn of the key in the truck it started and ran.

Immediately it was off.

The idle seemed way low. about 500 rpm if i let it fall it would die.

The engine seemed sluggish not firing right.

I have reset the distributor many times and have had it hard to start or just crank crank crank. Both.

Has started several times during distributor re-positioning.


Yes I will test the crank sensor.


A local shop owner says you absolutely have to use a computer to set the timing on these?

Any thoughts on that? Software to buy?

I'm tempted to fork over some dough and get this done at the shop.



Thanks for the help.
OK now some more data it actually started an ran at one point. OK the bomb shell I was holding back,,, you just can't stick a different cam into a fuel injected engine!!!

Now you need to look at an external data processor to be added to your computer that defines the changes made to the engine, or a computer tune down load.

Go here FastChip

Bogie
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 11-30-2012, 05:59 PM
Registered User
 
Last photo:
Join Date: Jul 2012
Location: Colorado Springs
Age: 30
Posts: 73
Wiki Edits: 0

Thanks: 51
Thanked 1 Time in 1 Post
I do already have scanXL with gm enhanced but I can't figure out if I can read the "CMP offset" or "camshaft retard offset".

Heres the procedure:

Perform the Camshaft Retard Offset adjustment procedure as follows:

With the engine OFF slightly loosen the distributor hold down bolt.
Start the engine and raise the engine speed to 1000 RPM.
Using the scan tool monitor the camshaft retard offset.
Rotate the distributor as follows:
To compensate for a negative reading rotate the distributor in the counterclockwise direction.
To compensate for a positive reading rotate the distributor in the clockwise direction.
Repeat step 4 until 0 degrees offset is obtained.
When 0 degrees has been obtained turn OFF the ignition and tighten the distributor hold down bolt.

The owner of the speed shop where I got the machine work done insists that this cam works in this engine just fine with no PCM mods.

Is he lying to me?
Reply With Quote Quick reply to this message

Tags
350, chevy, efi timing, ignition timing, start-up

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:
Insurance
Please select your insurance company (Optional)

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
350 not start has fuel and correct timing mwyoung Engine 7 07-07-2012 06:42 PM
FAST EZ EFI hot start issue redride Engine 9 05-29-2012 06:49 AM
EFI Chevy won't start. Why? willys36@aol.com Engine 5 10-18-2009 07:35 PM
Chev 5.3 efi Motor sputter at start bennett Engine 12 01-25-2006 11:42 AM
383 stroker efi - first start william27103 Engine 2 01-04-2006 09:36 AM


All times are GMT -6. The time now is 10:43 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.