You want a big lazy turbine and a smaller compressor for towing. Actually a 75mm S400 Borg Warner should work great and happens to be one of the least expensive options. If you go with a smaller more responsive turbine, you could very likely run into problems burning exhaust valves

 

Thanks, did some digging online and didn't find much in terms of "bolt on kits" is the reason for the posting. At this point I don't even know if this is a good choice for the swap. LS turbo combo seems popular in racing and hot street applications but your concerns regarding valve failures and such are my fear as well.

Looking at the turbo you recommend I see a listing for .90 to 1.25 AR housing option, how does this affect response and power? This isn't necessarily a towing application but the rig is a shoebox aerodynamically so it will be pushing hard anyway you slice it.

Any sources for headers/crossover for a single setup like this?

 

With all that room, fabbing up a single turbo starting with cast exhaust manifolds should be pretty straightforward.
I would upgrade the exhaust valves to ferrea super alloys or get the gm ly6 1.59 inconel valves, part number 12612427 due to the extended high loads.
Use good fasteners, get a proper cam with super mild lobes compatible with a nice beehive spring and it should last for years.
I have been thinking about doing this to my 2wd stick 2500hd. It would be fun to tow for sure!
Good luck with the project!

 

Thanks, I actually have a 4.8 take out engine I'm going to start mocking up. Been wanting to turbo something for awhile now.

 

96mm turbine T6 1.32. Trick turbo makes some bad ass cast drivers side mount exhaust manifolds, for sure in a T4 flange, possibly in a T6. Them and On3 make bolt on T4 single kits for 99 up trucks. I've been told by someone with personal experience that the quality of the crossover isn't "Custom" quality

 

I have a s475 t6 1.32 96mm on my tow rig

Had it on a 6.2 and saw full boost of 6 psi at 2000 rpms..towed my enclosed very well with next to no pedal

I now have same turbo on a 402 and it's responsive as can be...

KBracings or trick both make good turbo kits for trucks...I made my own that is similar to both of those

 

Thanks for the sources! I appreciate the hell out of it. Stay tuned for more questions as I go full turbo newbie.

 

I had a KB Racing kit on my 2013 5.3 CC Z71 with a S400 74/83 1.10 AR.. It made 500/550 on 8 lbs and I normally ran 12 lbs.. Only issue I had was trying to keep a 6L80E in it but you shouldn't have any issues with a 4L80E..

 

I run the 6l80 and been boosted since 2014...have came across scales at 15,800.... my trans still going strong

Big issue with a 6l80 is person behind keyboard...cant tune them like a 4 spd

 

On a bright note, I may have talked him into keeping the 440 and getting an overdrive and going with injection.

This now makes this project even better cuz I get to do the truck to my likings. Going to try to snag a truck this weekend to get started.

Where do you start on cam selection, this is a serious question.

 

I was just gonna say, I would do a goodself learning FI setup on the 440/727 and just bolt up a gear vendors to it