Put the 70 psi spring in and was very happy with the results keep my fuel psi above 60 when full throttle with stage 2 injectors.

Went with the middle of the road spring. Great throttle response. Sounds smoother at idle.

Great part fantastic customer service. I will be continuing to reccomend yor company!

Works as it should, checked every spring fuel psi, right on the money

I have just installed the gold spring not long after the oil crossover pipe it has made it run slightly smoother again and quieter again on the hwy. Slightly more power and has smoothed the engine out right through the rev range . Even noticed less cackle another awesome product from riffraff.

I used the gold spring and it works good. Honestly can't tell much of a difference in power. Idle is a little smoother. Spring is definitely a little longer than the original I took out but went back really easy.
Mines stock other than
TS6 position chip
6637 intake
Wicked wheel 2
4 inch turbo back exhaust
Oil crossover

Great product..

Fuel system is much happier. Quieter injectors, smoother power curve, 1mg increase. I installed gold and have 175s, curious about black though.

I only wish this kit was available with the special beveled o ring that seals the poppet.

Overall very happy

I am running the recommended spring for my stock engine. It definitely quiet it down and smoothed out my idle I haven't hooked up a gauge to see what my fuel pressure is. I would recommend it