1969x11

iTrader: (36)

I am in the process of building a tow rig. The platform is a 1987 Chevy V3500 Crew cab 4x4. The truck will have a lq4/80e and 4.10 gears in the dana 60 and 14 bolt rear. I will fit the biggest intercooler I can in the front and buy a good meth kit. The fuel will be 93 octane, single walbro 450 and deka 80's. Big power isn't the goal for this truck nor do I want to be in boost constantly. What would you guys use??

smokeshow

iTrader: (17)

If you actually want to use it for towing and not just something you pull a boat with once a year...then run something like a BW S468 T4.

1969x11

iTrader: (36)

I wanna be able to pull a fifth wheel camper >10,000lbs anywhere I choose.I will check out the s468...Thanks Jake

smokeshow

iTrader: (17)

You might want to check out a better radiator/cooling system with that weight. Stock stuff wasn't meant to handle the extra heat from an additional 100+ horsepower at any substantial duty cycle.

93camaro_zzz

iTrader: (13)

I have a 2003 2500HD (LQ4/4L80e/8 lug 14 bolt) and I also have considered turboing it. For me, I was thinking between a 70mm-76mm. I was actually leaning more towards the 76. From my experience with towing, you dont need the turbo to spool in 0.02 milliseconds, there is ALOT of load on the motor when towing. But like you said a larger turbo will make the power you want at a lower boost level, and be more resistant to unnecessary spooling when you are not towing. My truck makes 300 flywheel hp right now, and I was thinking if I could have it at the 450rwhp but hopefully at or over 500 torque, that would be pretty good with me I think. That would be about a 225rwhp increase over stock. I should notice the difference.

smokeshow

iTrader: (17)

Try not to get caught up by the idea that a bigger turbo will always make your desired power at a lower boost level. This is untrue; a turbo's isentropic efficiency does not begin decreasing as soon as it crosses into a pressure ratio range greater than 1:1. In fact it is quite the opposite. Some turbos need a ratio of 2:1 or more to really breathe well, so the efficiency of the turbo will increase to an extent while boost is increased.

Also, while considering 'load' on the turbo, don't forget to factor in RPM, as that is as much a part of load as throttle position is. If you use a turbo that is too large, you may not be able to build enough boost to make it useful while towing. For example on my own truck, my twin setup is just a hair too large to really make enough torque to pull large hills without downshifting under 65mph or so. I discovered this when my cruise control decided it should downshift and go full throttle up a hill with a 5k pound load...it got my attention really quick At 65mph, I'm under 2000rpms...its just not enough exhaust to drive the turbos. It would take hills with no issue at 75mph, but you're not always towing at that speed. So a smaller turbo is absolutely beneficial when the primary goal is maintaining torque at low RPM.

1969x11

iTrader: (36)

Ok so I have this little master power 70 with a .96ar on my rcsb and I am ready to move to bigger turbo on that truck... how would the mp70 fit the bill for my towing application? I have read that backpressure issues would make greater EGT's but 8-10psi on this cammed lq4 should give me plenty of power to tow with.

93camaro_zzz

iTrader: (13)

Keep us updated on what turbo and numbers you get. I am interested.

smokeshow

iTrader: (17)

That would be a good choice. EGTs won't be a concern because ECT will become an issue first. lol

evillsx

iTrader: (7)

I have heard of guys getting less than 5mpg when towing with set ups like this?
What do you guys get?

dmaxvaz

iTrader: (1)

turbo gas sound cool, but i would seriously consider swapping a 12 valve cummins turbo diesel into that chassis. 10,000 + lbs is alot of weight and overheating would almost happen all the time.

gpr

iTrader: (6)

I have always wondered and wanted to do this myself. build a turbo LS motor to pull with. I would error on the small side of a turbo so you are making more power down low and don't need to spin 4500-5000 rpm up every hill.

I wonder how it would compare to a diesel? I'm assuming towing large loads with a gas engine with turbo is not going to get very good mileage.

1969x11

iTrader: (36)

I salvaged this 6.0/80e from one of my trucks. I look at it like this engine was free and I will install and build the turbo kit. A Cummins would be nice , my brother tried to get me to put a duramax in it but it would be $$$$. There has to be a way to keep it cool. We shall find out

1969x11

iTrader: (36)

I don't expect the mileage to be to good. Most ton trucks with the 6.0 only get around 10-13 city this has been my experience anyway.

code4

iTrader: (30)

I know Kurt tows some heavy **** with a gas turbo. I remember reading about him running a second radiator but can't find it.

Here is some info about his tow rig: https://ls1tech.com/forums/forced-in...comes-end.html

smokeshow

iTrader: (17)

Yeah its not going to get great mileage lol. You can make tweaks in the tune to lean out the mixture at lower boost levels to conserve fuel...that's where you'll be while towing anyway. I run .86-.87 Lambda on 6psi and runs great. Tows really well.

93camaro_zzz

iTrader: (13)

Yeah it seems like a double edged sword run it slightly leaner to help with mpg, but then it will run hotter and we will still be in trouble with ects. The double radiator idea is a good idea though. And god knows the chevy trucks have plenty of room in the front!

smokeshow

iTrader: (17)

If the truck is going to be in boost for anything other than accelerating from a stop or on bigger hills, cooling upgrades are a must. There's a reason a Cummins radiator has its own zip code

93camaro_zzz

iTrader: (13)

I totally agree, I have to pull my transam on a trailer up the side of a mountain to get to my local race track with the truck in my sig, and there is one part that is a very long stretch of a big incline, and I can't keep into the throttle the whole way or else the temps raise to over 230*. My truck is stock though.... unfortunately.

Sarg

iTrader: (6)

Don't think you need a baby turbo to get quick spool. I have a s480 with the 92mm turbine on my lil 5.3 and I see positive pressure before 2500 Rpms and full boost before 3800 Rpms. This is a t6 1.10 ar turbine.