Suspension Drop/Brake Question

[Cam17]

I'm working on my '89 C1500 LD 5.0L. I'm planning on dropping it 2/4" with spindles in the front and drop shackles in the back. I've heard good things about the McGaughy's lowering kits, so I was looking into getting one of those.

I'm also planning on doing a complete overhaul on the brakes. The previous owner didn't do anything other than maybe change the brake fluid since the truck was new, and so the brakes are almost completely shot and pretty unsafe. I was thinking new dual piston calipers/rotors/pads in the front, and drum to disc conversion in the back (along with new brake lines, adjustable proportioning valve, probably new master cylinder, etc.). It might also be good to mention that I'm thinking of swapping out the 305 that is currently in it for a 350 (maybe 383 stroker) in the future.

In looking into those kits, I noticed that there is one for 1" and one for 1.25" thick front brake rotors. The truck currently has 1" rotors, but since I'm completely overhauling the brakes, would it be a better idea to get the kit for 1.25" thick brake rotors and then get all of the other front brake components to switch to that (could I even do that without messing something up)? Also, how much does the brake rotor thickness actually matter when it comes to stopping power in comparison to the single to dual piston caliper conversion? Any other advice/things to consider for this or things I might be missing?

Also what are thoughts on Doetsch Tech drop shocks vs Belltech? Any suggestions regarding what drum to disc conversion parts to use?

Thanks for the advice!

 

[gearheadE30]

The thicker rotor just gives you a bit more thermal mass and marginally better venting through the rotor. It won't help stopping power, but it would make a difference with repeated stops, especially from high speed, and with towing.

You aren't going to notice much going to the 1.25" thick rotors, but I would suggest the upgrade mainly because it's easier to get parts down the road as all of the later trucks used the thicker rotor. The caliper will make more of a difference, as will getting rid of the QTU master cylinder which should be done if you are changing calipers and makes a big difference even if you aren't.