Not sure what route to go...

[DQ Dave]

Hey all,

I have a 2017 denali with 20k miles on it. I don’t drive a whole lot as I work close to my business and in the winter months I’m gone traveling.

I’m looking to put some power to the truck. A few years ago I had a trailblazer SS with some work done, went to a Subaru sti, had some kids and well now “family” man haha.

I’m on the fence about what to do. Do I get a warranty for another 6years/60k miles through GM for 2700$ or do I drop the truck 3-4” and do some motor work? A supercharger? Just a cam, headers, and exhaust? I guess I’m looking for some advice.

I know I want to put 24” rims on it and lower it, but do I stop there?

Thanks all
Take care
Dave

 

[iamdub]

If you're "looking to put power to it", then the warranty would be a waste. Do what you're gonna enjoy most- Would a "stock" Denali with an extended warranty for as long as you keep it [mostly] stock do this for you? Pretty sure we all know the answer already. That $2700 is half the cost of a good supercharger kit. Or, it'll cover the smaller supporting mods for a supercharger.

 

[DQ Dave]

If you're "looking to put power to it", then the warranty would be a waste. Do what you're gonna enjoy most- Would a "stock" Denali with an extended warranty for as long as you keep it [mostly] stock do this for you? Pretty sure we all know the answer already. That $2700 is half the cost of a good supercharger kit. Or, it'll cover the smaller supporting mods for a supercharger.

You’re definitely right. It’s my opinion and I’m on the fence so I need a little slap, thank you.

If I’m to go power on it, is there any ideal route for those of you have put +100 hp to it? Have you ran into any issues?

Again, thank you.

 

[gat0r]

see if your dealer will work w/ you on magnuson supercharger & keep warranty

similar to what callaway & other tuners have done.

 

[hcvone]

I used to mod my trucks, six Suburban's, then twelve Escalade's, always had to worry about warranty if you tuned the truck, so what I did this time is I ordered a Callaway Tahoe, my closest Chevy dealer is setup to service Callaway Corvette's and now their trucks, so you get a warranty and Chevy can repair it, and the truck is a blast to drive

 

[wjburken]

For me, one question I would ask is are you able to work on your vehicle? If you have the tools and are able to wrench in it in your garage, I’d skip the warranty and go for power. If, on the other hand, you would need to take your vehicle to the dealership if anything needs fixed, I’d say get the warranty, work with the dealer on what mods you can make without voiding it.

I have never purchased an extended warranty myself, much to my wife’s, frustration, but that’s me. I personally would save up money in a savings account for repairs to a level I am comfortable with and then start getting the power mods I wanted.

 

[Captain Insaino]

I'm a big fan of heads, cam and full exhaust, but for something this heavy I personally would opt for a good spec'd blower cam with little overlap, upgraded fuel, cooling (maybe some meth in the intake charge) and around 9-11lbs of boost via a roots blower with a really good and safe tune. Not sure if you're 2wd, but gears as well for a dependable sleeper with LOTS of torque. I'm not sure of what our transmissions can handle, but again, if you're 2wd, a nice stall converter would be a fun edition.

 

[Rocket Man]

I went with a cam, blower and headers on my 02 Denali and I am glad I did every single time I drive it. It’s lowered 2/4 with suspension upgrades and Wilwoods so it handles and stops great too. So if you want to make it fun to drive, I say do it. These things can be made to accelerate and handle amazingly good.

 

[iamdub]

I say skip the cam and slap on a quality supercharger kit. They're designed to work with an otherwise stock setup and it'll be more than 100HP- plenty for fun. If you did something "small" to get 100 HP, it'd have to be a cam. That requires digging into the engine and that 100 HP will get old REALLY quickly and you'll be looking for the more expensive stuff anyway. As the others have said, you CAN get a supercharger and maintain the warranty, so you can satisfy the angel and the demon on your shoulders. It's pricey, but, you gotta pay to play. At least this is playing responsibly.

 

[Subanbur]

I say skip the cam and slap on a quality supercharger kit. They're designed to work with an otherwise stock setup and it'll be more than 100HP- plenty for fun. If you did something "small" to get 100 HP, it'd have to be a cam. That requires digging into the engine and that 100 HP will get old REALLY quickly and you'll be looking for the more expensive stuff anyway. As the others have said, you CAN get a supercharger and maintain the warranty, so you can satisfy the angel and the demon on your shoulders. It's pricey, but, you gotta pay to play. At least this is playing responsibly.

What supercharger would you choose and can you run supercharger on regular pump gas 87?

 

[gat0r]

magnuson or whipple are nice

87 would suck w/ boost... but, if you like detonation & knocking, give 87 a try (may get some engine damage as well)

 

[iamdub]

What supercharger would you choose and can you run supercharger on regular pump gas 87?

I'd have to research the fine details of all the offerings, but I'd definitely get a roots style blower such as that from Whipple, Magnuson/Radix, Edelbrock, etc. rather than a centrifugal. Running 87 should not even be a question. If you're considering putting a $6,000+ supercharger on a vehicle you don't drive a whole lot, then spending an extra $9 per fill-up shouldn't even be a concern. These things should be fed 89 or higher in stock form, anyway.

 

[Subanbur]

magnuson or whipple are nice

87 would suck w/ boost... but, if you like detonation & knocking, give 87 a try (may get some engine damage as well)

Lol no thx

I'd have to research the fine details of all the offerings, but I'd definitely get a roots style blower such as that from Whipple, Magnuson/Radix, Edelbrock, etc. rather than a centrifugal. Running 87 should not even be a question. If you're considering a putting a $6,000+ supercharger on a vehicle you don't drive a whole lot, then spending an extra $9 per fill-up shouldn't even be a concern. These things should be fed 89 or higher in stock form, anyway.

I’m just wondering why you would need supreme 91 oct if your not playing with the compression ration.Your basically pushing in more air. I understand higher compression = higher octane to reduce knocking or pre-donation. On my civic si I never ran with anything but 91 or better ,it’s recommended fuel anyway . Now looking up at the stats of the l83 ,it has the same compression ration as the k20z3 11:1. Why are they recommending 87 for the suburban?

 

[Rocket Man]

Lol no thx



I’m just wondering why you would need supreme 91 oct if your not playing with the compression ration.Your basically pushing in more air. I understand higher compression = higher octane to reduce knocking or pre-donation. On my civic si I never ran with anything but 91 or better ,it’s recommended fuel anyway . Now looking up at the stats of the l83 ,it has the same compression ration as the k20z3 11:1. Why are they recommending 87 for the suburban?

Boost pressure behaves the same way as an increased compression ratio since you’re starting with an increased atmospheric pressure. 91+ is required for my Whipple supercharged 6.0. Otherwise it would knock constantly and destroy the engine.

 

[Sam Harris]

Boost pressure behaves the same way as an increased compression ratio since you’re starting with an increased atmospheric pressure. 91+ is required for my Whipple supercharged 6.0. Otherwise it would knock constantly and destroy the engine.

91 is the best I can get in Co. [emoji3525] which I use in all my vehicles (except E85 in my Yukon [emoji6]).. I mean... unless I bought race gas.. [emoji3166]

 

[Rocket Man]

91 is the best I can get in Co. [emoji3525] which I use in all my vehicles (except E85 in my Yukon [emoji6]).. I mean... unless I bought race gas.. [emoji3166]

Yep me too. It’s the minimum octane Whipple recommends but that’s the best I can get pretty much anywhere in Oregon except maybe a few stations.

 

[iamdub]

I’m just wondering why you would need supreme 91 oct if your not playing with the compression ration.Your basically pushing in more air. I understand higher compression = higher octane to reduce knocking or pre-donation. On my civic si I never ran with anything but 91 or better ,it’s recommended fuel anyway . Now looking up at the stats of the l83 ,it has the same compression ration as the k20z3 11:1. Why are they recommending 87 for the suburban?

As the others have said, it's to stave off preignition. The more pressure in the cylinder, the hotter the air and the more easily it ignites. Diesel engines kinda run off of detonation. You can have high compression with no knock by retarding the timing. On your Si, it was tuned to run on 91. Your L83 with the same compression is tuned to run on 87. Yes, it's kind of a waste, but the engineers have to meet specific criteria. It's easy to manipulate the timing to account for varying fuel grades. You can't really manipulate the compression ratio. You can a little (the dynamic compression ratio) with variable camshaft timing (VVT), but it's nothing like the adjustability with spark timing. So, you make the static compression ratio high and have the knock sensors tell the PCM how far it can advance the timing to make the most of whatever fuel is in it. Run 87 and it'll only advance the timing so far and you'll only get X amount of power. Fill up with 93 and it'll advance the timing a little further to take advantage, yielding more power. This is all on a naturally aspirated, stock engine. With a supercharger, you need 91 at a minimum.

 

[Subanbur]

Thx guys , I really appreciate the input. I was wondering how’s the fuel economy on a supercharger?

Is there a way to use a clutch type system like on a A/C compressor to engage and disengage the blower pulley on the fly ? Does that make any technical sense ? What about having a propane/gas hybrid + supercharger. Propane is 110 octane.

 

[gat0r]

that was a movie prop in mad max

although i thought procharger has some option a few years back that allowed boost to be turned down to 1# & then could crank it up when real power was needed. think it was controlled in the tune, versus a dial though.

 

[91RS]

If you can afford it, I would go for a Magnuson supercharger. Their kits bolt right on and I've seen plenty of used vehicles that still have them on after years of use so they're reliable. Then you can have a vehicle that drives like stock but has 150 extra horsepower. I'm doing a cam in my 08 but ONLY because I want to replace the lifters before a failure. If I had a newer truck that I had no reason to go into, I wouldn't bother with a cam. The only downside to a supercharger is the cost.