12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

stretched afc spring and I need some tuning advice

Thread Tools
 
Search this Thread
 
  #1  
Old 05-14-2011, 08:40 AM
almostthere's Avatar
Newbie
Thread Starter
Join Date: May 2011
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default stretched afc spring and I need some tuning advice

I heated and stretched my stock 215 afc spring about 1/2 inch. The tension is tight, I havn't checked it with air, with the starwheel backed just out of sight. I just put in the injectors and turbo and I needed advice on getting my boost up earlier. I have been playing with the pre boost screw regularly with no real effect(about 1/4 inch of thread showing past the locknut). AFC is forward and 0 fuel plate is 1/8" back of forward. The boost needle won't move until 1200 rpms and doesn't really climb until 2500, it cruises at 65 in 5th gear at about 6psi boost. I was hoping to get the boost to show up sooner and needed some advice on tuning to get it right. I was going to get a spring kit, put the light one in and set it with air to 25-30psi and try that and then turbo and manifold blankets to try to get it where I want it. I have a timing kit coming and will bump it to 16.5*. Would the spring tension effect this? Any other tuning advice would be appreciated or someone in the southeast that could have a look and set it up just right would be great.
Tyler
 
  #2  
Old 05-14-2011, 09:12 AM
12vcummins96's Avatar
Administrator

Join Date: Aug 2009
Location: Pearland Tx
Posts: 5,765
Received 340 Likes on 273 Posts
Default

so your saying that turbo is that laggy something else is wrong if it wont light till 2500 rpms
 
  #3  
Old 05-14-2011, 09:32 AM
almostthere's Avatar
Newbie
Thread Starter
Join Date: May 2011
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default

It probably lights earlier than that, 2200 or so. Its non wastegated and I just got it from ED with the injectors to match so I am thinking it is in the tuning. I just got it on last week. I will continue to mess with the pre boost screw on the back. It doesn't smoke at all right now so maybe it needs fuel a little earlier. It ran good before hand and lit early, fuel pressure 31-32psi, and I just did the afc mods(stretched spring, ground lip off washer and barrel, and backed out pre boost screw), injectors and turbo so I am just looking for some ideas so I am not just guessing what to do next. Heating and stretching that spring along with no smoke makes me think it is requiring too much boost to move the foot until you get up in boost pressure then it releases the fuel and takes off.
Thanks
 

Last edited by almostthere; 05-14-2011 at 10:18 AM.




All times are GMT -5. The time now is 10:32 PM.