Part 2 of the update, it's amazing when you have a truck how many people call on you.. "heyyy... so you have a truck, right......?..." haha.. I'm pretty sure I'm the only person with a truck that a lot of my friends know. Anyways, she gets loaded often and put to good use.
After having the intercooler coupler between the driver side charge pipe and the intake horn blow off multiple times on the northern BC trip, I had to replace with what I could find.. which was blue and about 1.5" too long, so it jams and acordians the angled reducer elbow coupler at the intercooler. And having a coupler on the turbo side blow off while hauling my friend's car, well I just decided I'd replace all of them.. with black. These BD Diesel units seem good quality, fit pretty well (tight to the OD of the pipes).. in hindsight it would've made things a bit easier if I misted some water on the piping to get them to install a bit easier.
The old couplers that didn't blow off previously were really stuck on to the pipes, but once that fit was unstuck I could fit a screwdriver between the pipe and the coupler and they just farted off. I guess 20 years of heat and pressure will loosen up the material.
Coupler between turbo outlet and passenger side charge pipe...
Coupler between passenger charge pipe and intercooler..
I then decided I wanted to try and reconfigure the intake filter setup, to buy myself a bit more room around the filter so I could fabricate an aluminum shroud/case around it, that I can wrap in heat foil and make a duct to pull air from an area cooler than directly above the turbo. This meant ditching the popular BHAF (Big Honkin' Air Filter).. that filter is cheap, works well, and lets the turbo sing... but man is it huge.
Previous rejigged stock setup with BHAF..
Just for the heck of it, I thought I'd attempt an ABS intake... which is something I never thought I'd do. The OD for 3" ABS pipe connectors is right around 4", so I thought I'd see how much I could bore it out and maybe it'd work.
The straight coupler worked well and I was able to bore and trim it to about 1/8" wall thickness, and turn the OD, so that I could ABS glue it to the 45* elbow to adapt a 4"-ID-inlet AFE cone filter I got to the ~4.375" ID of the OEM rubber inlet tubing. The elbow I tried to bore out as smooth as I could as there where some lips inside.. I think the average ID of it is now around 3.625"... probably a bit small but I was curious to try it.
Option #1.. AFE filter, ABS elbow, OEM rubber elbow...
Option #2 is to use the parts from an extra S&B cold air intake that came with the truck, but was missing a coupler and some fasteners. The ID of the S&B rubber coupler is about 4.5", which tightened down onto the elbow contraption. This is the setup I decided to try for a bit to see if I could notice a difference. The turbo whistle is definitely quieter up until maybe 1500rpm, then it starts to sing again thru 2000rpm. I noticed the truck builds the same boost but seems to smoke a tiny bit more when chugging along under load maybe 1200-1500rpm.. so I'm thinking the step down from the previous ~4" ID to the now ~3.625" ID restriction at the elbow is preventing it from getting just that little bit more air as the turbo is beginning to spool. I'm now looking at trying a 5"-ID-inlet filter of similar size, with 5" OD 45* bend aluminum elbow, and lathe a transition down to the 4.5" ID of the S&B coupler.