AFC spring kit? pros/cons

[Deezul1]

Getting ready for a TST #11 plate soon and wonder about others experience with the AFC kit. I dont mind mild smoke but dont like the dump truck look except under WOT. Now the waste gate is disconnected and making 34lb boost with 370s.

TIA

John

 

[SLang]

Running light spring in mine. With 370's smoke is minimal compared to factory injectors. If you want little smoke I would at least change to the medium spring. With a little control the light spring is nice to drive.

 

[Don M]

Light spring= less smoke, less low rpm fueling

Medium spring= little more

Heavy spring= you get the picture



I changed my AFC spring to the lighter one in the begining to cut down the low boost smoke.

Once I changed to the 16CM2 housing I pulled that dude out and went with the heavier one.



Adds a little low end power to combat the low boost. Smokes a ton though.



Don~

 

[HEMI®Dart]

Don,



Correct me if I'm wrong, but the different springs should give have these characteristics:



Light spring: More smoke & more fueling at low boost.



Medium spring: Less Smoke and less fueling at low boost.



Heavy spring (stock): Scrap it





Deezul 1,



IMO, There are no cons to an AFC spring kit. Get one and install the medium spring, with the star wheel all the way retracted (towards the front of the engine). There will be a little bit of "pre-load" on the diaphram because the AFC springs in the kit are longer. This is what you want anyway. I never have had to adjust my star wheel from the fully retracted (rich) position. In fact, I have LESS pre-boost smoke & MORE low end torque with the meduim spring in the kit than I had with the heavy stock AFC spring. They are easy install too.



Here is more info I dug up from Ted Jennety's AFC spring kit install directions:





"The AFC housing's, and especially those of the 215 hp engines , use a very stiff spring that opposes the movement of the AFC link forward. Full link travel in some cases requires 34+ lbs of boost. It can be difficult to minimize the smoke level by just the "star wheel" (moving the "star wheel" towards the rear of the housing) with the OEM heavy spring to reduce low boost smoke will reduce the power level below the level possible with an AFC spring kit. Sometimes seriously the hotter torque plates"



In other words, you're losing low end power with the stock heavy AFC spring.



" Changing the spring to one in the JRE AFC spring kit ensures that full AFC link travel occurs with a reasonable amount of boost, and allows smoke control by adjusting the star wheel. The spring tension is sufficient to allow smoke adjustment without reducing power at usually attained boost levels. The spring is a bit longer to give a bit of "pre-load" without turning the star wheel so far that full link travel may be impeded. Engine responsiveness and power under initial acccelaration and at medium rpm's will be greater, as verified by dynomometer testing. 2 Springs are included in the kit. The lighter of the springs is made from thinner diameter wire, and is noticeably easier to compress. The medium spring is usually best with the 215 hp engines.



In other words, If you have to turn the star wheel alot (with the OEM heavy afc spring) to try to reduce smoke, you're preventing the AFC diaphram from moving all the way forward to the max fueling position , and losing hp & torque thats attainable with a lighter AFC spring.





Hope this helps. No this wasn't off the top of my head ( the bold writing). . Its Ted Jennety's writing.

 

[Don M]

Yeah Hemi... I was backwards... Im still tired from being out of town too much. . I just cant sleep when away from home too long.



I did install the medium on the last go round. .





Oops!



Don~