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Towing with a supercharger

JohnnieMo

SM 2017
PM 2014
SM 2013
Full Member
Joined
Jun 2, 2011
Messages
905
Location
Calgary, Alberta
I'm getting a new 22 foot tow boat this year and I am trying to determine how to mod my 2008 LTZ. It has the 5.3 and 3.73 gears with trailering package.

The boat will be around 6000 lbs and I won't haul it too much. However when I do it will be a good 500km. If I add a blower will I start spitting out drive train parts? I don't mind going the blower route but I don't want to destroy the rest of the truck.

It is a slow drive but there are a lot of good hills, topping out at 4500 ft elevation. I drive it pretty easy and I'm not the type to drive aggressively the rest of the year either.

Anyways just looking for some advice on how to proceed from others running boost.

 
I'd say you'd probably be best with a Magnuson SC for good low end torque.  Should probably also upgrade servos for better band holding power.  Afterwards you may want to get a custom tune to adjust tranny shift points.
 
I towed a 28' travel trailer with my Magnacharged Avalanche, without load-equalizing hitch. I was only towing it one time, from the point of purchase to the farm, a total distance of about 250 miles. Towing was pretty much effortless; I hardly knew the trailer was back there. It was extremely easy to maintain 70 mph highway speeds, regardless of the steepness of the hill. I occasionally tow other items, but most of these are lighter-weight (maybe 2000 lbs tops) so they really don't even count as towing in my mind.

If you decide to do it, another absolute must is a good transmission oil cooler, and this is regardless of whether you go with the supercharger or whether you don't (not sure if the new-model towing package has an external TOC; the first-generation did not).
 
RedRocketZ28 said:
It will pull that just fine in stock configuration.
Remember the truck is easily 7000lbs alone and with the boat I'm now at the max combined weight of 13,000lbs. Add the hills plus elevation and I can't imagine it will be a pleasant experience.

It does have a Trans cooler (and even a temp gauge In the DIC) I'm not sure if the stock cooler is good enough though.

My alternate approach is intake, headers, exhaust and gears. My shop does amazing custom tunes either way so no worries there. They coaxed 500rwhp out of my Trans am with vortech blower.
 
Can anyone comment on the survivability of the drive train in this situation? I'm looking for personal experience and not opinion. I don't want to add so much power as to start spitting teeth out of the transmission or rear end. If upgrading the transmission in needed then I may go for a reduced horsepower option.
 
A stock Magnacharger is delivered at about 5 psi. Add a Corvette servo to the tranny and make sure the tranny cooler is sufficient and you should be good to go unless you dog the pi$$ out of it all the time. You've already stated you drive easy, which means you should be fine. At the 5 psi boost level towing will be pretty easy for you.

The Magnacharger has been on my truck for about 9 years now. It's been cammed for about 5 years, pullied down, and stalled; I'm at about 8 psi. I've put about 55k miles on it and haven't touched it since it was first installed. I don't dog the crap out of mine either, but when I want to run it, I do. That includes full throttle shift points at 6300 rpm.

All of that said, there are no guarantees. There are tons of Magnacharged vehicles out there at the stock boost level that have survived for at least 100k miles.
 
Thanks, that is quite helpful.

I have a supercharged Trans Am to play with, so my truck is just for getting the family from A to B.  My only concern are the long hills out in the Rockies where I am tugging up hill at a high elevation for 10+ miles.  It is those climbs I'm looking to get through with everything in one piece.  I can go slow, but if I am going to do that, I may as well leave the truck as is.  Clearly that isn't acceptable.  :p
 
JohnnieMo said:
Remember the truck is easily 7000lbs alone and with the boat I'm now at the max combined weight of 13,000lbs. Add the hills plus elevation and I can't imagine it will be a pleasant experience.

Wow, GM added that much to the new style truck?
When I bought my 2003 Z71 1500 Avalanche the weight listed for it was 5600...
Can't remember where I saw the weight but was no where near 7000.
 
redheadedrod said:
Wow, GM added that much to the new style truck?
When I bought my 2003 Z71 1500 Avalanche the weight listed for it was 5600...
Can't remember where I saw the weight but was no where near 7000.

It is 5800 and change curb weight. Gvwr is 7200 and I'm using most of that with my family and gear on vacation. Not to mention 250lbs of gasoline!
 
Glad to see all this info on superchargers. I recently started towing a Toy Hauler travel trailer with my '08, 5.3, 3.73 rear, flex fuel engine with trailer package.  Pulling a maximum total load of about 6,500#, on level surface it is fine (which is okay in South Fl) but even a moderate +grade I really have to dog it to keep it going.

I spoke to a friend who is a GM mechanic and after he explained my options he suggested a supercharger. He said either a Edelbrock or Whipple should work fine. I read about both and while I like the Edelbrock's appearance I prefer the overall options of the Whipple.  Also, he said that with the Flex Fuel engine it will not require a fuel pump change and the 3.73 will work fine for what I'm hauling.  When I go supercharger I am considering a Borla Cat-Back exh.

Any thoughts before I dig very deeply into my bank account?



 
The Edelbrock is a good unit, but it's more expensive than a Magnacharger. I would personally choose a TVS 1900 over the Edelbrock.

I haven't been in the market for a supercharger for a long time, but the last I knew, Whipple had issues with poor after-sales support and the supplied tuning. As long as you have someone who can do your tunes, the Whipple units are capable of more power than the Edelbrock or TVS 1900. Any of the units should provide all of the power you need to tow.

You definitely need a good tranny cooler, and I would suggest you add an aftermarket cold air intake in addtion to the cat-back. You need more air into the engine to go along with the additional air that the freer-flowing exhaust allows out. It wouldn't hurt to at least consider adding a Corvette Servo to  the tranny.
 
I did some further research and agree with MyBigToy. I've ordered the Magna TVS 1900, 6th Generation and a Borla Cat-Back ss Exh system. Magna was $5,700 out the door.  Borla was $820.

I already have a K&N Cold Air Intake I'd like to use with the Magnacharger.  They claim an average 120hp gain and hopefully it will be at least that much with the CAI and Borla.

That will put me in the 440hp range.  I'll find out in a couple of weeks.

A friend of mine is a GM mechanic in Orlando Fl, and is sending me a "good" tranny cooler (?).  I'm going to ask him about the Corvette servo.  Thanks for the input...
 
JohnnieMo said:
Remember the truck is easily 7000lbs alone and with the boat I'm now at the max combined weight of 13,000lbs. Add the hills plus elevation and I can't imagine it will be a pleasant experience.

It does have a Trans cooler (and even a temp gauge In the DIC) I'm not sure if the stock cooler is good enough though.

My alternate approach is intake, headers, exhaust and gears. My shop does amazing custom tunes either way so no worries there. They coaxed 500rwhp out of my Trans am with vortech blower.

My buddy pulls a Crownline 225br with a 05 Tahoe.  My cousin has a Crownline 245ss (4,800lbs. without trailer) and pulls it with a 2012 Tahoe.  I recently pulled my 01 Z28 (3400) on a 16+2' trailer (~2000), with 4 people in my truck, another set of tires, floor jack, tools, luggage, etc., on a 3 hour trip running 75 mph no problems in my basically stock Avalanche that has 110k miles on it.  Yes, there were hills involved.

I think you will be more than fine pulling a 22' boat every once in awhile.  What 22' are you getting that weighs 6000 lbs. anyway?

By all means though, supercharge your Avy.  I would build a turbo kit for my truck if I had the time to do so.  It would get a 4L80e like my Camaro has though before that.  The 4L60e will not last long with more than stock power even with a cooler.
 
RedRocketZ28 said:
By all means though, supercharge your Avy.  I would build a turbo kit for my truck if I had the time to do so.  It would get a 4L80e like my Camaro has though before that.  The 4L60e will not last long with more than stock power even with a cooler.

While I agree the best bet would be to move to an 80E (it's a LOT of work that I'm not ready to tackle), I've got 55k miles on the 60E/supercharged engine combo (77k miles total on truck), with about 30k of that cammed and stalled, and I've had no tranny issues so far. The tranny is not stock, but it's what would be considered pretty mildly built. Better frictions, a shift kit, hardened separator plate, Beast sunshell, aluminum accumulator pistons, and billet servos (and I wish I had just put in a Vette servo for 1-2 shift portion as the 1-2 shift hits way to hard, even with the shift pressure turned down and shift time turned up - there's just too much apply area on the billet servo). I don't dog the crap out of the truck, but I also don't baby it. If I decide I want to floor it, I do; that's why I bought the supercharger.

Maybe I'm just lucky, but I suspect many of the people who have issues with a 60E behind a supercharger are those that take full advantage of the supercharger all of the time.
 
How do I know which Corvette servo will fit my '08?

Someone told me to first make sure that the 08 tranny used a servo.  He thought that some later models might have switched to electronic devices and eliminated the servo.

I saw this one on Ebay for $15.15, NEW CORVETTE SERVO 700R4 4L60 4L60E TRANSMISSION.  As you can easily tell, I am new to supercharging and all that it entails.
 
hollywood Av said:
How do I know which Corvette servo will fit my '08?

Someone told me to first make sure that the 08 tranny used a servo.  He thought that some later models might have switched to electronic devices and eliminated the servo.

I saw this one on Ebay for $15.15, NEW CORVETTE SERVO 700R4 4L60 4L60E TRANSMISSION.  As you can easily tell, I am new to supercharging and all that it entails.

This appears to me to be what you need:

http://www.ebay.com/itm/CORVETTE-Servo-2ND-4TH-Servo-Piston-KIT-4L60E-4L60-700R4-4L65E-4L70E-M30-MD8/251165897039?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D261%26meid%3D111441615424947956%26pid%3D100005%26prg%3D1088%26rk%3D2%26rkt%3D5%26sd%3D161032956469%26

But what I've always been told is to just go to your Chevy dealer and tell them what you want, that their prices on this part are not much more than you can get it for over the internet, and that they typically have them in stock.
 
Hollywood,

Are you have any second thoughts about sinking major money into a 5 year old truck? That is the hardest thing for me. My truck only has 120,000kms on it but it just seems kinda silly to put so much money into an older avalanche. I'm struggling with it.

However I've looked at new avalanches, new sierras, and f150's and nothing is a silver bullet for what I want. Plus I already have the money for the blower. So keeping the Av means no truck payment. I just want to make sure I get another 7 years out of the truck.

As my wife said "you're nuts if you think you're getting a new boat AND a new truck!"

The boat I'm getting will be a Tige. Either an rz2 or z3.
 
JohnnieMo said:
Hollywood,

Are you have any second thoughts about sinking major money into a 5 year old truck? That is the hardest thing for me. My truck only has 120,000kms on it but it just seems kinda silly to put so much money into an older avalanche. I'm struggling with it.

However I've looked at new avalanches, new sierras, and f150's and nothing is a silver bullet for what I want. Plus I already have the money for the blower. So keeping the Av means no truck payment. I just want to make sure I get another 7 years out of the truck.

As my wife said "you're nuts if you think you're getting a new boat AND a new truck!"

The boat I'm getting will be a Tige. Either an rz2 or z3.
I am selling my S/C if interested for half the cost, if interested email me. hemicharger08awd@gmail.com
you will only need tune and fuel pump add on (which is less than $60). (y)
 
Johnnie,

My '08 Avy just rolled 25K. I use my 2010 HD more than the truck. Also, the truck is already blacked out, has 6 month old black rims and tires, air lift rear and 1.5" front lift. All LED/Fiber Optic lights, cab clearance lights, side marker lights, mid-gate 60/40 platform, etc. And it's paid for.

When I considered all that it seemed worth it to throw some money into the power side.  I hope to keep it at least another 5 years.  The Borla exhaust arrived today. Looks good in the box.  We'll see.

As for the tranny, a friend of mine who builds trannys and rear ends and is considered an expert in the field, told me he can simply boost the pressure 5-10 lbs and keep everything OEM.  He said the shift will feel pretty much the same but it will perform better with the extra horsepower.  He strongly encouraged me to forget the Corvette servo. 
 
Turning the pressure up will improve the shift feel, but does not do the same thing the Vette servo does, which is increase the apply surface. You get better clamping pressure over a larger surface area. It's a long-time proven mod that works to help the tranny live longer, which turning the pressure up will not.

Check out FLT Transmission if you want expert advice on a good tranny for our trucks. They build some of the strongest 4L60E trannies out there for our trucks. There's a big difference between a 4L60E surviving behind a high horsepower 4000 lb. Camaro versus a high horsepower 6000 lb. truck.
 
I was also prompted by my shop NOT to do the corvette servo. He said proper tuning does enough to clean up the shifts.

The way I see it, I am throwing away half the price of the blower as soon as I buy it but it should slightly improve the resale if I ever sell it. I'm looking forward to getting the avy moving a little more quickly.

 
hollywood Av said:
That will put me in the 440hp range.  I'll find out in a couple of weeks.
Fyi my shop showed me some dyno sheets of other 5.3's they have done with the Magnason kit. (they have done hundreds btw). They are seeing around 360 to 380 rwhp depending on the aggressiveness of the tune. I think that is with only the kit and nothing else. I honestly expected more. Torque was about the same. Obviously the good part is that it is available at 2000 RPM.
 
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