Tow pig power upgrades

So I have a 01 Suburban 2500 6.0 . Bone stock and well taken care of from the last owner. 170k miles on it. I just replaced the radiator and added the biggest transmission cooler I could get.

Now I'd like to do some power upgrades. It has 3.75 gears and I'd like to keep them. I usually tow my 25 foot tritoon to a few different lakes and would like more power for when I have to lug it up the hills in the mountains.

My wife drives it a few times a week to haul the alicorn kid to the barn so it has to be something she can get into and drive without blowing up.

Cam, headers and a tune ?

Turbo ! Ok she'd blow this up..

Supercharger ? 

Give me your thoughts please..

No duraburb.

I would be interesting to see a Sloppy style turbo set up for towing instead of street racing.  I’m sure it could be done.

I'd use a radiator from an '07-up (it SHOULD fit the existing core support) and electric fans.  They can be controlled by your existing PCM just by adding two fuses, three relays, and adding a couple wires to the PCM, and using software like HPTuners to enable them.  (The existing fan shroud will not work, the new radiator is anout 6" wider)  It will run cooler on the highway and cooler temps means less likely to go into some sort of engine saving mode.

Then, headers.  Then monitor the engine when it is under heavy stress and see if it's going into any self-preservation modes like catalyst overtemp enrichment.  I had a customer with headers on an 8100 and he loved the increase in hill oomph that he didn't mind having to pay us to replace the gaskets every 20k or so. 

Turbos sounds fun but it won't work without the same kind of cooling that a Duramax has, and for the same reasons...

In reply to Knurled. :

So your saying a Duramax turbo will work ?

Positive displacement supercharger sounds like the answer to me.

scottdownsouth said:

In reply to Knurled. :

So your saying a Duramax turbo will work ?

No, and I am not sure how that would come across.

In reply to scottdownsouth : A cam doesn’t magically make power, the engineers that designed the engine let it make all the power it can within the operating parameters.  They have access to the same cam options you do.  

Yes they have cams that do make more peak power at the expense of power at lower rpm.  If you are building a motor for racing then yes get a cam. Or they can give more bottom end power at a cost of worse fuel mileage and greater wear.  But it’s all a trade off. 

As for headers. Let’s clarify terms. True headers are equal length and based on the camshaft’s operating parameters.  Power at low RPM ( which is easy to feel) requires longer tubes the same length for each cylinder.  

Most of what is sold aren’t real headers.  Tube diameters may be too big, length is wrong for stock camshafts, and they aren’t equal length. Those”headers” should be called tubular exhaust manifolds.  

Can they add power? Maybe yes, a trivial bit if the stock manifolds are particularly bad .  Here is one area where the potential for improvement exists.  A lot of compromises can exist for packaging purposes. 

A tune?  Your best bet but please remember there is no free lunch.  If more power is created more fuel will be used.  Plus the potential exists for damage. 

The factories spend a great deal engineering and perfecting the tune. You won’t get something for nothing. 

In reply to frenchyd :

These engines respond well to tighter LSAs, which will really boost midrange torque.

If you're trying to make more power at like 3000 rpm I'd say headers and a tune. Maybe E-fans. If you're looking for a big power gain at a low rpm you're pretty limited on what you can do while naturally aspirated, and i think boost is just going to trade problems for different problems.  Now if you are WOT and doing 4000+ rpm during these moments of inadequate power then the run of the mill bolt ons might actually do a lot for you. 

As much as I love turbos, I don't know how well they will do on  gas burners going up a long hill . Staying under 10-12 psi may be the best, but then how much power will it be making there and how much will a cam and such make ? It may be a wash. 

The burb towes fine on flat roads and 65-75 mph. Big hills kill it and that's when you have to floor it and let it rev .

Dyk..the Chevy and Ford  turbos are kissing cousins ? 

If you're flooring it and letting it rev then a cam may be a huge improvement in your case. 

Also, 10psi of boost on a 6.0 will blow literally anything you can do to an NA engine out of the water, torque wise. Cams generally don't make massive improvements in peak torque, they just move around where peak torque happens with incremental change to what the peak torque actually is. A stockish engine with a cam won't make tons more torque at peak, it will just make more high rpm power by moving the torque peak up in rpm. 

Durability under boost would be my chief concern. Oh you might get up a hill or even a mountain faster but the probability of whatever time you save being spent repairing the damage is too high.  

One thing that absolutely must be done to any engine using boost is open up ring end gaps.  To control leakage with resulting blow by oil ring end gaps are as tight as possible.  But the heat of boost will cause the rings to expand, closing up end gaps until the ends butt together. Then they curl up or down which blows the ring lands off and the engine is done. 

Durability is key.... you want something that will do high load for MINUTES at a time.  Not some bolt on forced induction that is good for 4 or 5 seconds at a time before the too-small intercooler is heat soaked.

Note that GM and Ford are going back to large displacement gas engines for their gruntmaster HD trucks.

A friend of mine has a 1500 Avalanche 5.3 that he slapped a blower on.  Four transmission rebuilds later he uninstalled the blower and drives slower.  He said that 500 hp was a blast to hoon around with but something always gives.  

With your (and mine, I have a 2500 'burb 6.0 as well) rig the trans is much more durable than the weenie 4L60e but the truck is heavy and "fast" just isn't really it's game.  Mine is a 2004 with a 2007 engine, is there more power from newer motors?

Electric fans, long tube headers(with hi-flow cats), a ported throttle body/intake manifold and a tune. Maybe a cold air kit?

Id stick with a quiet exhaust setup though as a loud truck towing is absolutely horrendous for your mental health.

The e-fan alone was a great upgrade on a few of the trucks/suv's i have had in the past. I dont suggest a junkyard setup though. I have had bad experiences with junkyard fans on daily drivers. Flex-a-lite has a nice setup for most installations that i would trust over a budget junkyard setup.

 

kevinatfms said:

Electric fans, long tube headers(with hi-flow cats), a ported throttle body/intake manifold and a tune. Maybe a cold air kit?

Id stick with a quiet exhaust setup though as a loud truck towing is absolutely horrendous for your mental health.

The e-fan alone was a great upgrade on a few of the trucks/suv's i have had in the past. I dont suggest a junkyard setup though. I have had bad experiences with junkyard fans on daily drivers. Flex-a-lite has a nice setup for most installations that i would trust over a budget junkyard setup.

 

Isn’t that the truth.  I remember my dad bringing home a time-capsule ‘74 C10 one day back in the mid ‘90’s.  We pulled the fan, dropped in a Flex-a-lite plus a $20 junkyard HEI distributor, fresh plugs and wires, and added the biggest and quietest Flowmaster we could find just behind the Y-pipe —leaving the rest of the exhaust on the garage floor.  The butt dyno said that truck picked up 100 hp.  Not really of course.  But it sure felt like it.  I attributed the biggest gain to the removal of the fan.

Will an Efan help in a diesel as much as a gas motor? 

Talk to these guys about a cam. 

Then talk to these guys about a tune. 

grover said:

Will an Efan help in a diesel as much as a gas motor? 

Probably not, given the sheer size of the cooling stacks that they are using.  I have a good feeling that this was a good chunk of why Ford eliminated having a radiator and an intercooler and an oil cooler and a power steering cooler and a trans cooler and just went with an engine radiator and an everything-else radiator that liquid-cooled everything.  It's HARD to pull air through a 8" thick stack of "stuff".  (Also hard to plumb!  And you can't rust out your transmission lines if you don't have transmission lines...)  Most electric fans won't cut it trying to pull air with that much pressure drop, you need power.

I only suggested the e-fans mainly because the 34" wide radiator I suggested had them available, and the nose airflow on the Chevy trucks SUCKS.  You can get a situation where the fan clutch is in stangant air and the clutch disengages.  The HD trucks get around this somehow but I fixed a 1500 that had big overheating problems on the highway with a plow on the front by converting to the big radiator and OE (well, Dorman) electric fans.  As a bonus, it also runs cooler on the highway all the time, and the A/C works a heck of a lot better.

Will an Efan help in a diesel as much as a gas motor? 

Simple answer is no. A diesel engine fan actually uses MORE power at equivalent rpm than a gas version because it needs to do more cooling. I wouldn't put an E-fan on a modern diesel truck because its cooling needs are probably going to be more than what a run of the mill e-fan setup can handle. Consider that a 30 amp fan (rare) at 12v is 360w, or about half a HP. Engine Masters just did a dyno test showing typical old SBC 18" engine fans take 10-20hp to drive. Diesel fans are MUCH larger diameter (new duramax is 28"). Not a particularly good comparison but gives you a sense of scale of how great the power difference can be between a clutch fan and E-fan. The engine fan may not convert all 20hp (or way more in the video below) to air movement, but the conservation of energy theory says that the e-fan CANT convert more than half a hp into wind. You can stack up e-fans or find crazy ones and wire for them blah blah but the appeal goes away when you realize how hard it would be to make an e-fan setup truly equivalent to the clutch fan on a modern diesel. You realistically couldnt replicate the air moving potential of the stock fan without doing some serious reengineering of the stock electrical system so you could flow hundreds of amps into huge fan motors.

Gale Banks talks about the clutch fan on a modern diesel in this video a bit:

Fan part is in the middle.

Before we go nuts here, post the RPO for the engine.  If it's an LQ9 I have different recommendations than if it's an LQ4.  The LQ9 basically has LS6 heads with larger chambers, so it would respond differently than an LQ4 with different flow.

I wouldn't fuss too much with physical engine parameters like cam or headers.  The factory manifolds are actually very good for chunks of cast iron.  Intakes are great.  They flow about the same as an LS6 intake.  The only reason they didn't use them in cars is that they're too tall.

GM does an amazing job of matching components, so if you swap out something like heads, cam, or intake, it won't be the magic bullet that makes a bunch of power.   It would take a pretty comprehensive swap of things to make significant power changes.  I wouldn't change the cam without changing heads.  You can do a modest cam change and still keep things matched, but you'll only gain a wee bit of oomph.

Cam swaps on LS motors can get hairy if you go outside the GM parts bin.  Valve lash is not adjustable, so lash is set by the pushrod length.  The shaft-mounted rockers don't look like anything special, but they are wonderful and stoopid reliable.  Don't let anyone sell you on upgraded rockers.

Look into some of the changes you can get with a tune.  Some will require 93 octane, but in general you can usually lean out the fuel trim a bit and gain 10 or so HP.  Factory tunes run them a tad rich to balance NOx and HC emissions.  The timing can be bumped up (again, they keep it conservative for NOx) but that is where you'll likely need the higher octane.  The two mods (fuel and timing) should get you 15-20hp.  Add another couple hp with a good air intake and exhaust.

Thanks for all the suggestion, I believe I'll get a tune first and do a good duel exhaust. Anyone ever use PCM of nc ?

It has the lq4 in it for what it is worth.

I'm thinking about the efans to help out the AC when were sitting in traffic.The AC works great while you're moving,but sucks when you're sitting still. The thing never runs hot, and now with the trucool trans cooler I should be good to go !

Vigo said:Consider that a 30 amp fan (rare) at 12v is 360w...

You should see some of the stuff coming out nowadays.  My "weapon of choice" is the fan package from an early 00s Chrysler 300M, which each will pull in the 35A range on high, and there are two of them.  The twin fans for the Silverado I posted above will draw 18A each.  The mongoid '13-up GT500 fan requires a 40A as well when on high.  And I don't know how much power a Ford Flex's fan set pulls, but I have two sets sitting in the garage waiting for me to do something with them (the fan controllers died, and were only available as fan assemblies).

They still don't move as much air as a good belt driven fan can.  Part of this is because of power availability, the rest is because electric fans tend to be mounted right up against the radiator, while optimal fan position distance is something like half the diameter of the blade, minimum.  So the fan needs to be pretty far from the radiator and well-shrouded, so the fan is pulling air from the whole core with no dead zones.

scottdownsouth said:

Thanks for all the suggestion, I believe I'll get a tune first and do a good duel exhaust. Anyone ever use PCM of nc ?

It has the lq4 in it for what it is worth.

I have never used that company, but try Bryan Herter of PCMforless.com if you want.  He does all my LT1 stuff.

The LQ4 has either 317 or 035 heads and 9.4:1 compression from dished pistons.  The cam is 196/207 with a 116 LSA.

The LQ9 is the same basic assembly, but with flat-top pistons that are actually .025 above deck at TDC for 10.1:1.  Cam is very similar, but a degree or two different. 

This page outlines some LQ4/9 performance mods, but I disagree with him on cam choices.  He tries to make you believe that just adding 10 degrees of intake duration will magically make 50 more hp at the wheels.  Intake, exhaust, tune.  Then see how you feel.  If you want to up the ante, you could swap to LS6 heads (243) to bump the compression.  They're not dreadfully expensive... Bare used castings can often be found for $250/pr, fully assembled heads more like $350-400/pr.  LS2/3/6 cams are not advised for a truck... they give up too much down low.  Stick with something in the 210/215 range with a 112 LSA.

I actually put CNC ported LS6 heads on an LQ9 for a whopping 11.4:1.  If it doesn't rip the head studs out on 93 octane, it should make close to 600.

Well I do have a spare 4.8 with 799 heads I believe, was out of a van I was told. Was going to build a turbo motor for a rx7 that never happened. Maybe if I'm not happy with the tune and exhaust I'll slap in a cam and heads. I was just reading some magazine says they made 70+ hp with a bigger camshaft.