What is the word on underdrive pulleys these days for a 5.3 liter? I seen a 2 piece set on Summit Racing and Jeggs, but was wondering if the are a waste of time and money?
I had a 3 piece set on my 1990 Chevy 5.7 and the only time I noticed them was when I was pulling a trailer. At night at idle the lights (dash and head lights) dimedand A/C fan motor slowed down. I was also wondering if it will increase the MPG too?
When i installed them on my 1990 I also installed an Edelbrock intake and Hypertech thermomaster chip and thermostat at the same time. So I did not get to check the MPG or Horse power increase.