...

Go Back   Lateral-g Forums > Technical Discussions > LSX Conversions
User Name
Password



Reply
 
Thread Tools Display Modes
  #1  
Old 10-10-2018, 09:30 PM
sic7camaro sic7camaro is offline
Junior Member
 
Join Date: Jun 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Default Need help, 67 Camaro with rhs 502

When I go to start it, the starter seems to engage the flywheel and spin the motor a little and then a loud bang and it seems like the motor kicks back the opposite way.
Sometimes it will turn and fire up, but seems like it runs a little rough.

Here is a video I made of it. The first two starts are with the coil harness plugs disconnected and it spins the motor fine like that. The others are with them connected and you can see how the motor seems to kick back https://m.youtube.com/watch?v=gmSln5mdTEc

Last edited by sic7camaro; 10-10-2018 at 09:52 PM.
Reply With Quote
  #2  
Old 10-11-2018, 08:17 AM
dhutton dhutton is offline
Senior Member
 
Join Date: Nov 2006
Location: Mountain Springs, Texas
Posts: 1,373
Thanks: 49
Thanked 25 Times in 18 Posts
Default

Too much crank timing advance is my guess.

Might be useful to tell folks what EFI controller etc you are running.

Don

Last edited by dhutton; 10-11-2018 at 08:54 AM.
Reply With Quote
  #3  
Old 10-11-2018, 10:23 AM
sic7camaro sic7camaro is offline
Junior Member
 
Join Date: Jun 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Thanks for the reply, okay so it has a pcm out of a 2004 gto and a vaporworx fuel controller, and the pcm has a base tune in it.
Reply With Quote
  #4  
Old 10-11-2018, 11:09 AM
dhutton dhutton is offline
Senior Member
 
Join Date: Nov 2006
Location: Mountain Springs, Texas
Posts: 1,373
Thanks: 49
Thanked 25 Times in 18 Posts
Default

Quote:
Originally Posted by sic7camaro View Post
Thanks for the reply, okay so it has a pcm out of a 2004 gto and a vaporworx fuel controller, and the pcm has a base tune in it.
What cam? Base tune from a 2004 GTO?

Don
Reply With Quote
  #5  
Old 10-11-2018, 05:17 PM
sic7camaro sic7camaro is offline
Junior Member
 
Join Date: Jun 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Its a cam motion hydraulic. I had a base tune done for the 502 motor
Reply With Quote
  #6  
Old 10-11-2018, 06:33 PM
dhutton dhutton is offline
Senior Member
 
Join Date: Nov 2006
Location: Mountain Springs, Texas
Posts: 1,373
Thanks: 49
Thanked 25 Times in 18 Posts
Default

I’m no expert but I think the timing is too advanced when cranking. I would get a better tune. Maybe one of the experts will chime in.

Don
Reply With Quote
  #7  
Old 10-11-2018, 08:49 PM
Che70velle's Avatar
Che70velle Che70velle is offline
Senior Member
 
Join Date: Aug 2012
Location: Dawsonville Georgia
Posts: 1,997
Thanks: 59
Thanked 26 Times in 20 Posts
Default

Quote:
Originally Posted by dhutton View Post
Im no expert but I think the timing is too advanced when cranking. I would get a better tune. Maybe one of the experts will chime in.

Don
I completely agree here. You need to get HP tuners/EFI Live scan of your cranking ignition timing, before you try to start the car again. It will likely break the starter boss off the block, if you continue. If it were an Oem block, it already would have broke. Check the timing first. Ive seen this many many times.
__________________
Scott
---------------------------------------------------------------
70 velle' on custom chassis w/custom RideTech coilovers, RED sleeved 434 with Mamo 265s, built T56, 12 bolt 3:73, wilwood 6/4's, bla, bla, bla...build. thread https://lateral-g.net/forums/showthread.php4?t=39631
New 434 engine build here https://ls1tech.com/forums/generatio...ved-block.html

Thanks Dad!!

My Chevelle is old school... It has a belt driven power steering pump.
They're 17's, but I keep em clean!
Reply With Quote
  #8  
Old 10-13-2018, 09:29 AM
572Camaro's Avatar
572Camaro 572Camaro is offline
Member
 
Join Date: Nov 2016
Location: Central Missouri
Posts: 88
Thanks: 1
Thanked 11 Times in 6 Posts
Default

I watched the video.
My guess is you have too much ignition timing advance during cranking.
Please please put a timing light on and check during cranking.
My guess on your application is you want about 15-18 degrees btdc while cranking. That means you want 15-18 degrees between 0-400rpm.

I have a F.A.S.T. fuel injected 572ci 68 Camaro.
I completely shredded my flywheel when it backfired through the intake when I had cranking timing set at 22 degrees btdc.

Please don't do what I did! Ugh.....,

Keep us posted. You have friends you've never met who care!

Last edited by 572Camaro; 10-16-2018 at 10:07 AM. Reason: 28btdc, sorry.., not 22btdc
Reply With Quote
  #9  
Old 10-15-2018, 01:06 AM
sic7camaro sic7camaro is offline
Junior Member
 
Join Date: Jun 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Thank you for all the help, I will definitely check crank timing this week.
I will let you guys know what I find with that
Thanks again
Reply With Quote
  #10  
Old 10-16-2018, 10:15 AM
572Camaro's Avatar
572Camaro 572Camaro is offline
Member
 
Join Date: Nov 2016
Location: Central Missouri
Posts: 88
Thanks: 1
Thanked 11 Times in 6 Posts
Default

sic7camaro,

I apologize for an error..,
When I shredded my flexplate, the crank timing was 28btdc, not 22btdc like I posted earlier.

Sorry.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -5. The time now is 07:03 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Copyright Lateral-g.net