Moroso 72300 Advance Curve Kit, Fits GM HEI Distributors

good quality working good perfect fit

They make two different styles for HEI. I recommend you take distributor cap of and verify they is your style. Worked good for me,and I used the middle springs for timing advance all-in at 2800 rpm.

I had installed an aftermarket HEI which had a horrible timing curve. Using this recurve setup i was able to use one light and one medium spring to bring in all my timing by around 3200rpm.The timing advance starts around 1100rpm and comes up perfectly smoothly through the RPM range.This fixed a part throttle bog I had when towing heavy trailers with my truck and generally increased my towing experience.No directions are included, but if you google Moroso 72300 you'll find the instructions which show the different spring characteristics.I would 100% recommend installing these.

I was looking at the Crane advance kit but they were sold out. I stumbled onto this kit and I’m very happy with it. Installation was easy, the bushings that were supplied were perfect and the spring are of good quality too. Between this kit and and the adjustable diaphragm, I had a noticeable difference in feel. I installed it into a 1970 455 HEI conversion.

Purchased to upgrade a GM hei distributor. Three different sets of bushings are included, the only one even close to fitting were the black ones. They are incredibly tight going into the included weights. Next time I will use the original weights and drill them out so the bushings will fit them. I feel the original weights are a much better setup. I used the medium springs ,its working fairly well. I will experiment with the other springs in the near future. Be sure to take a few pics of the original setup so you can install the new stuff correctly.

I needed to recurve my timing and this had everything I needed.

fixed my problem

Didn't receive all the springs