So heres what ive got going on took my 86 iroc off the road for alittle over a month to do some work on her, installed founders rear kit did a diff fluid change KN filters BBK Underdrive Pulleys new water and power steering pumps. Car ran great prior to these mods. I drove it yesterday and the hotter it gets the louder it knocks, it doesnt knock at idle or in gear (atleast i cant hear it if it does) Its more like a rattle that will increase with rpm. I dont want to say its rod knock because it doesnt sound like a Cummins. I have already installed 1.6 stamped rockers previous to this noise happening. Car revs strong and pulls strong no lose in power if anything it gained alittle with the new mods. Any info would really help thanks in advance.

 

Detonation?


Your water pump is running slower now, so it may not be cooling as well, which could cause hot spots and lead to detonation under load.

What octane gas are you running?

 

I'm running regular gas however the under drives I bought would no affect to cooling and charging because the water pump is slightly bigger than stock as well as the alt.

Should I run a mid grade gas?

 

The call them Underdrive pulleys because thats what they do, underdrive your accesories, otherwise, they are useless.

What ones did you get?


I would run 89 octane at least.

 

OK cool I'll try that on my next fill up