# Supercharger



## 23krsfan (May 29, 2006)

I was thinking about adding a magnacharger radix onto my truck. This weekend when I took the 23KRS fully loaded my '05 Silverado 5.3L 3.73 4x4 was struggling up some steep grades. My wife thought is was going to blow up. As of now I have Hypertech programmer and Flowmaster catback exhaust. I hate to spend the extra dough but I think it will help prevent getting the birdie from angry drivers as they make their move to pass


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## PDX_Doug (Nov 16, 2004)

I don't know anything about the MagnaCharger specifically, but from the looks of the other mods you have done to your TV, I would say it is definitely in order!

BTW, Let me know if the ploy works on your DW!
















Happy Trails,
Doug


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## Oregon_Camper (Sep 13, 2004)

23krsfan said:


> ...snip...
> but I think it will help prevent getting the birdie from angry drivers as they make their move to pass
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Let them be rude...you're going camping. In a few more hours you'll be tilting back a cold brew and they will still be rude!


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## NJMikeC (Mar 29, 2006)

23krsfan,

With all due respect I think that would be a waste of money. I could elaborate at great length but I'll keep it short.

With the money you spent on the hypertech and exhaust you could have maybe bought a 4.10 rear. Then with the money you will spend on that supercharger you could have gotten an exhaust but you should always start at headers first which provide lower RPM torque gain.

Essentially I believe you are heading in the wrong direction and are thinking of HP not torque. Pardon me for sounding tutorial but you need the latter as in Torque which is work, which is pulling that trailer. HP is the rate at which you do work. The word rate brings in time or speed.

2 examples point this out rather easily: Think light racecar. Far lighter then your truck and trailer for that matter. Once you get that light racecar moving you want it to move at a high rate which is where HP comes into play. Higher HP means you are moving it at a higher rate going faster , winning races.

Diesel engine- look at the torque vs. HP ratings then also note the RPM's that a diesel turns and where it develops that peak torque and HP. Very low HP number due to the rate at which the engine spins but tremendous low RPM torque due to the high compression ratio and long stroke.

I looked at many modifications for many vehicles which I have owned. The hypertech increases both torque and HP but keeps the peak RPM levels the same. Essentially you got more but probably at less fuel efficiency, premium gas, higher temp something. There are no freebies here.

You want to bring the peak torque down to a lower RPM . That will save you downshifts in the trans going up those hills and also keep that motor running at a lower RPM which is closer to the peak torque RPM. That is efficiency in a nutshell.

Then bring that 4.10 into play and we got that setup some GRUNT!.

PM me if you want to continue this discussion.


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## camping479 (Aug 27, 2003)

Don't forget about the transmission, more torque, more strain on the trans. You could be putting money into that soon too if can't handle the extra torque while towing.

Tell your wife not to worry about it blowing up, the 5.3 has no problem running at higher rpm's.

Mike


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## PDX_Doug (Nov 16, 2004)

NJMikeC said:


> I could elaborate at great length but I'll keep it short.


Short?

You have learned well, my son!
I'm just so darned proud!









Happy Trails,
Doug


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## 23krsfan (May 29, 2006)

NJMikeC said:


> 23krsfan,
> 
> With all due respect I think that would be a waste of money. I could elaborate at great length but I'll keep it short.
> 
> ...


Some valid points but why do you advise against the supercharger? I got the hypertech and exhaust when I got my truck lifted and aftermarket wheels put on. I have my hypertech set to use 87 unleaded and it corrected my speedo with the big rim and tire setup. The MagnaCharger install is a bit exspensive but it will add 120 horses and torque which should give me a little over 400 on both. I fiqured I got a decent deal on the truck last year when GM had their discounts and I could splurge a little bit on upgrades.


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## Scrib (Jun 28, 2005)

I'd do it in a heartbeat - but my Mustang's getting one (also Eaton-based) next month, so the TV will have to wait.


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## NJMikeC (Mar 29, 2006)

Supercharger is all about flat out power, more power, but in my mind fails to address efficiency at all. I believe you may have to change your hypertech , run Super unleaded all the time and to do it correctly think about re-tuning your exhaust. What about warranty? What about gas mileage?

So you have made some investments but I would put in the 4.10 next. It will not bog your motor so much and maximizes the efficiency of the drivetrain for towing. You will get less downshifts. Think of those down shifts . Trailer weight, plus truck weight plus gravity all are on those little valves in the trans when no doubt the trans is at it's peak temperature. Not a happy trans for sure. After the 4.10 I would try some headers from either Gibson or JBL and check if they reduce that peak torque RPM. I'm pretty sure they do and they also understand the difference between towing and racing. You will save even more shifts and you might just be done.

So to summarize if you do the Supercharger you will get much more power at much less efficiency in both the drive train and MPG. The 4.10 might just barely negatively effect MPG but will boost the efficiency of the drive train. With the 4.10 you no doubt will save maintenance money and gas money. Supercharger will mean more money on both.


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## PDX_Doug (Nov 16, 2004)

Sorry Mike, but I have to respesctfully disagree.

Correctly applied, any supercharging device (supercharger, turbo, whatever) will do more to increase efficiency than anything out else there. You keep refering to racing applications, and you are correct in your assesments of the benefits there. But let's take a look at the big rigs rolling down the Interstate. Every one of them is supercharged (via a turbo usually), and they are not about race car performance. They are all about two things... torque and efficiency.

As far as the 4.10 gearing is concerned, it is great for a lot of things (towing included), but efficiency is not something that one sees in the plus column. A 4.10 forces the engine to work much harder for the same result (speed). That harder work translates into better acceleration and pulling power, but at the cost of top end, drivetrain wear and tear and fuel mileage (especially when not loaded up).

Besides, from the list of mod's 23krsfan has listed for his truck already, it is obvious he is a motorhead, and as such his 'motivation' may be more than just what is openly being addressed.









I'd say mount that bad boy up, and enjoy the ride!

Happy Trails,
Doug


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## huntr70 (Jul 8, 2005)

Buy a diesel and forget about the gasser and add ons..........









Steve

If I added up what my truck cost new, plus what I've put into it to try to ugrade and get more from it, I could've bought a diesel in the first place.


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## kjp1969 (Apr 25, 2004)

huntr70 said:


> Buy a diesel and forget about the gasser and add ons..........
> 
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> 
> ...


Gotta agree- throwing money at the "wrong" truck just doesn't make sense- all you're going to do it find the next weak link in the chain, be it cooling, the transmission, or something else. Go for more cubic inches, or diesel, before you supercharge that engine. In a TV, anyway. Just my $.02.
Kevin P.


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## 23krsfan (May 29, 2006)

Thanks for all the great input. Yes, I now realize I should have gotten a diesel engine but this is my first TT so the learning curve is slow. I don't want to trade it in cause quite frankly I like the way the truck looks with my aftermarket mods. I don't want to start all over again. So supercharger here I come!


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## tdvffjohn (Mar 10, 2005)

A lot of good opinions to go on ..................Let us know what the difference is.

Take a pic of it installed.....Hot rodding a truck









John


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## NJMikeC (Mar 29, 2006)

23KRSFAN,

The supercharger will do it. Hope it works out.

Understand that you can't buy a new truck. My next one will be diesel as well.

Hope I was of assistance. I attended GM Automotive Design institute and have a little bit of soft spots for Chevy's not to mention a fair amount of knowledge both book wise and greasy hands wise. Favorites were of course engines but also fuel systems and automatic transmissions.


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## 23krsfan (May 29, 2006)

My only question is will my tranny be able to take the extra horsepower and torque? The tuners said "yeah man it'll do fine". That's the one thing that worries me. Any thoughts?


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## huntr70 (Jul 8, 2005)

23krsfan said:


> My only question is will my tranny be able to take the extra horsepower and torque? The tuners said "yeah man it'll do fine". That's the one thing that worries me. Any thoughts?
> [snapback]116537[/snapback]​


That is where it is a completely different scenario....the tuners aren't towing a 6000 lb + trailer behind their cars.....

You will discover soon enough where the weakest links are.

Steve


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## NJMikeC (Mar 29, 2006)

23krsfan,

Based on my creditials that I briefly outlined in a previous Post.I thought I adequaetely guided you with some well thought out factual advice. It was free at that!

So I will continue to do so which is the very essence of this forum.

I believe you have changed the operating point outside of the original design criteria which will show up as a reduction of lifecycle. The reasons I say that are in the previous posts. My recommended changes are also there which will keep you from reducing the lifecyle of your truck.

Another good piece of advice which I hope you don't find snide, but instead factual is:

This is a towing forum and I believe the the questions that you ask would more accurately and easily addressed in some kind of street race car forum.

Superchargers + V8 engines + towing +100,000 mi lifecycle---- This does not compute Will Robinson!


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## kjp1969 (Apr 25, 2004)

NJMikeC said:


> Superchargers + V8 engines + towing +100,000 mi lifecycle---- This does not compute Will Robinson!
> [snapback]116648[/snapback]​


Ya mon, best to pick your favorite three out of four and be happy with that!

Kevin P


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## GlenninTexas (Aug 11, 2004)

Hey 23krsfan,

One question. I assume since you have a 4x4 you've also added larger diameter tires. In fact I think you said the hypertec was used to adjust for this. If so, jkeep in mind that you have effectively changed the drive ratio, how far depends upon the difference between your stock and upgraded tire/wheels. So your 3:73 isn't 3:73 any longer. This is where your loosing the "umf" while towing I suspect and adding more hp/torque isn't going to help that much.

Regards, Glenn


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## MJRey (Jan 21, 2005)

23krsfan,

GlenninTexas beat me to it but I think alot of your difficulty isn't the engine but the "effective" drive ratio that you now have with those larger tires. You really need to figure out what your effective ratio is with those tires and then decide what to do. I don't know offhand how to make the adjustment for the increase in tire diameter but I'm sure someone here has the info or a link to a site that has it. It may be far more cost effective (even with the 4x4) to change your gear ratio to account for the tire change. An even easier option may be to switch back to the stock rims and tires when towing the trailer.

One more thing to consider before boosting the HP and Torque substantially with a supercharger is the durability of the driveline. The transmission was already mentioned but you'll also be putting alot of additional stress on the u-joints and differentials. The u-joints will be especially vulnerable to failure because you've lifted the truck and increased the angle they have to transfer the power through. Good luck with whatever you go with.


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## NJMikeC (Mar 29, 2006)

Correct Glenn and MJRey,

If the tire change for instance was from 27" to 28" the resultant gear ratio is now 3.60 down from it's original 3.73. All the more reason to go 4.10.


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## OVTT (Mar 31, 2006)

NJMikeC said:


> Correct Glenn and MJRey,
> 
> If the tire change for instance was from 27" to 28" the resultant gear ratio is now 3.60 down from it's original 3.73. All the more reason to go 4.10.
> [snapback]116759[/snapback]​


I agree!


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## MJRey (Jan 21, 2005)

Okay I found a quick was to see what your effective ratio is when you increase the tire size.

Effective Gear Ratio = Actual Gear Ratio x Original Tire Diameter /New Tire Diameter

This will get you close to the right answer. As an example if you change from a 30" to a 33" diameter tire with the 3.73 ratio you end up with an effective ratio of only 3.39 which is terrible for towing. For that example you need to go to a 4.10 actual ratio to get back to the 3.73 that you started with. Hope this helps.


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## Katrina (Dec 16, 2004)

Yup, I say the money is better spent on gears first.
Supercharger later if you must have it.


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## 23krsfan (May 29, 2006)

Everyone has posted some very useful info. I even ran out to the garage and check my tire load rating(3195lbs). I running Toyo Open Country M/T 35x12.50R20. I'm starting to lean towards the 4.10 gears cause it does make more sense now that you all have dropped some insightful knowledge.


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## NJMikeC (Mar 29, 2006)

23krsfan,

Fact is, inorder to get the maximim gain out of the supercharger for towing go even higher on the ratio. It's quite simple concering your high revving on hills. An equal torque applied to the pinion for both the following ratios produces greater force with the 4.10 but greater distance with the 3.73 as torque =ft lbs. On a 10% hill the load increased 10% as in a 10,000 lb GCW now is 11,000 .

The 3.73 didn't have that force thus the tranmission down shifted , requesting more torque from the engine to get that force. If you keep that 3.73 with the supercharger I believe to will go to RED LINE on that engine. The transmission will downshift and you will get an awful burst from that supercharger. I also worry about the fuel and exhaust system setup correctly to avoid pinging.

Now for the trans. If you insist going up hills fast or even faster you will heat the trans fast, faster. Hence me saying going to even 4:56 which will still reduce the max temp of the trans. That will help but you are still on the path to grenading that trans if fast up the hills is the requirement. All the trans cooler and temperature guages will not change that. You have max load at max heat. Bigger cooler only changed the max heat.

The irony of it all is that you will get your diesel faster if you have the money for it. That might be good.


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## kjp1969 (Apr 25, 2004)

23krsfan said:


> Toyo Open Country M/T 35x12.50R20. I'm starting to lean towards the 4.10 gears cause it does make more sense now that you all have dropped some insightful knowledge.
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With those tires (HUGE) I'd go with the lowest gearing you can, perhaps 4.56 is available? You're never going to get back all the power those wheels and tires are soaking up with any readily available gears, but every little bit will help. I won't even mention the increase in unsprung weight or reduced braking capacity.

Sounds like you really want two vehicles: Your tahoe and a stock (or stockish) tow vehicle!

By the way, how much lift do you have- 6" or so? Suspension or body lift, or both? Rear blocks or rearched springs? Betcha have a monster drop on your tow bar! Any brake work to go with those wheels/tires? My point is: how stable is your rig when the TV is jacked that much?

I don't mean to talk down your truck (I have a heavily modified miata myself, so I'm not adverse to that sort of thing) but modifying a vehicle like you have can raise a whole bunch of issues that wouldn't exist if you'd have left it stock. In fact, I wouldn't be alone is saying that you pretty much have to throw the factory tow ratings out the window and reassess considering what you've built!

Kevin P.


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## 23krsfan (May 29, 2006)

kjp1969 said:


> 23krsfan said:
> 
> 
> > Toyo Open Country M/TÂ 35x12.50R20.Â I'm starting to lean towards the 4.10 gears cause it does make more sense now that you all have dropped some insightful knowledge.Â
> ...


Easy killer I'm not looking for any flaming comments bro. It has a 6 inch lift. The tuner shop I took it to in Gilroy, CA (Advanced Truck) was highly recommended and I let them do all the mods. Really the biggest tire/wheel combo I wanted to go was 18's but they convinced me into 20's. As far as braking is concerned I was going to do the brembo big brake upgrade. I was just looking for some more umph when going up hills. I just like putting money into my autos. This is my 1st TT and when I get the upgrade bug I'll go for the 5ver and then upgrade to a diesel.


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## huntr70 (Jul 8, 2005)

23krsfan said:


> kjp1969 said:
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> > 23krsfan said:
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I don't think anyone is trying to flame you here....

We are all just giving our opinions, as that is what you asked for in the first place.

You need to make the final decision, whether it turns out to be the right one, or the wrong one.

The final decision and consequences or advantages are yours.

Steve


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## kjp1969 (Apr 25, 2004)

23krsfan said:


> kjp1969 said:
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Hey- I didnâ€™t mean to rile you, but in re-reading my last post I can see that you might take offense. This isnâ€™t me bashing you or your truck, Iâ€™m just pointing out a few facts and giving my opinions.

Iâ€™m no â€œexpert,â€ but I do have the unique and unofficial board title of King of the Towing Screwups. 6 weeks into ownership of our first TT, a 21rs, I wrecked it (and the TV) due to sway. If you were headed north on I-5 near Castaic on Memorial Day weekend, 2004, you had me to thank for shutting down the 2 right lanes for a few hours. Fortunately, no one was hurt. You can read all about the gory details at the thread entitled â€œWe Crashed,â€ but the short story is that we were towing with a â€˜98 explorer, which, although it had a Reese dual cam sway control, was a poor tow vehicle for a trailer that size. Lack of experience on my part also played a role, and Iâ€™ve been up more than a few nights thinking about that, too.

Anyway, this experience doesnâ€™t make me any more of an expert than anyone else, but you came here looking for comment, and I gave you some from my perspective. Just as a carpenter sees every situation in terms of wood and nails, I see every tow rig in terms of stability- for me, thatâ€™s paramount and power comes later. After all, you can always go up the mountain a little slower, but first you have to make it safely to the mountain. Other people may have different views, and thatâ€™s fine too.

Some TV mods can help trailering stability, but in my opinion yours havenâ€™t- you may have raised the center of gravity (depending on your new wheel offsets), and youâ€™ve definitely lowered your final drive, and probably doubled your wheel weight. That not necessarily fatal to anything, because you may have had enough â€œreserveâ€ stability that compromising it as youâ€™ve done wonâ€™t create a big problem. It doesnâ€™t mean youâ€™re going to crash or burn up your transmission or anything else, either. It does mean that you should recognize and accept these limitations, and compensate for them elsewhere if possible.

Iâ€™m not immune from this by the way- I havenâ€™t weighed it, but our new trailer probably blows past our TVâ€™s max tongue weight by a couple of hundred pounds. Its just something I keep in the back of my mind as I watch for tire wear, etc.

I hope this straightens us out, because I donâ€™t want to talk smack and I donâ€™t want to start a war with you or anyone else. Often when someone seeks advise on TVâ€™s, and I see something that looks unusual, Iâ€™ll mention it just on the off chance that they hadnâ€™t thought of it before. You can listen to me, disregard me, or whatever. This board has always been (for me) a place where you can get straight advice and no flame wars, and thatâ€™s why Iâ€™m here so often.

Kevin P.


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## 23krsfan (May 29, 2006)

No problem KP. If I'm gonna post 23krsfan has gotta accept corrective criticism. I am going to start with the final drive of 4.10 as my first mod cause after reading all the posts it's the most logical.


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## Scrib (Jun 28, 2005)

Heh - Kevin's post reminds me that as I was headed north out of Stockton last week, I got passed by a 6" lifted shortbox towing a ~24' Arctic Fox (not the lightest trailers in the world). Guy had to be doing 70mph.


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## GlenninTexas (Aug 11, 2004)

23krsfan said:


> No problem KP. If I'm gonna post 23krsfan has gotta accept corrective criticism. I am going to start with the final drive of 4.10 as my first mod cause after reading all the posts it's the most logical.
> [snapback]117837[/snapback]​


Just one more thought. I'm sure you already know this, but just in case, you'll need to change the gearing in both front and rear differentials.

Regards, Glenn


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