my friend bought a tst afc spring kit for his truck which came with a medium and a light spring. I put the medium one in his truck and he gave me the light one since he wouldnt need it. just wondering how good the light spring would do in my truck? thanks

 

That is the one I ran in my 5-speed 215 truck . Just let's the diaphragm move sooner, it takes less boost to move the AFC arm also lets you get a inside view of the AFC, also if you go this far flip your washers on the diaphragm allows for a hair more travel also!

Brandon

 

Works well and is more adjustable with the starwheel for the feel you want on the throttle. Anything is an improvement over the stock spring in the 215 pump.