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Please help with 4.3L HP increase?

TomBrady80

By TomBrady80
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DONWT15 Enthusiast

DONWT15

Posted
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1 hour ago, Donstar said:

Stock tire on a  factory 20" wheel is 275/55/20.  I think this is a comfortable riding and good looking tire size. 

I have that exact size with black factory wheels. They do look good, but "comfortable" is not the word I would use. Passable fits better but they run smooth without vibration and handle well enough at 32 to 33 PSI. Any more pressure than that and it gets to riding like a buckboard. 

 

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i82much
i82much

Stop!  You are wasting your money.  I had the old 4.3 Vortec and I never *needed* more power, your truck is a rocket compared to my old one.  If you want a faster truck, buy a truck with a bigger engi

TXGREEK
TXGREEK

Looks is what gets everyone into hating their ride. My truck came w 22”’s, had dealership downgrade to 20”s then had to order new rims, made the mistake going back to 20”’s cause they look good but wi

newdude
newdude

Procharger?  Would have to be a custom setup, but that might be a way to go.  E85 is the cheapest mod for the 4.3 as that adds some HP.  And the 4.3 comes flex fuel equipped.  If it can be tuned and o

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TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted
Stock tire on a  factory 20" wheel is 275/55/20.  I think this is a comfortable riding and good looking tire size. 


Looks is what gets everyone into hating their ride. My truck came w 22”’s, had dealership downgrade to 20”s then had to order new rims, made the mistake going back to 20”’s cause they look good but wish I had gone to 18”’s just more side wall would give me smoother ride and more sidewall protection too. 20”s tow less too.


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TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted
I have that exact size with black factory wheels. They do look good, but "comfortable" is not the word I would use. Passable fits better but they run smooth without vibration and handle well enough at 32 to 33 PSI. Any more pressure than that and it gets to riding like a buckboard. 
 
wheel.thumb.jpg.06c9c829af0988490ab56295d788d9d9.jpg

Absolutely agree


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DONWT15 Enthusiast

DONWT15

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To the OP: wheels and tires are cool and some are really sharp, but if you go bigger/taller it will show up in less responsiveness. It just takes more energy to turn bigger meats. I would look into a lot of the suggestions here on tuning to get more out of the engine. These Gen V engines are pretty good across the board. Somebody out there must have something for the 4.3.

Pearl2017 Enthusiast

Pearl2017

Posted
Posted (edited)

A lot of good and bad info I'm hearing. IMO spending thousands on forced induction or gearing to change your stock truck into something it is not is a huge mistake. If you want the bigger engine trade that sucker in and apply those thousands to get what you want. Tuning and CAI is cheap stuff that can wake up a sleepy machine. 6 or 8 speed trannies are the secret sauce that avoids having to do these more expensive add on's. The trans multiplies power and the tune optimizes shifting the available gears to get you there.

 

If you do want to tow be aware a tire with E load rating will handle the load better and I know for michelins can be aired yup to 80PSI if need be to safely carry a load. And they will have less rolling resistance than a smaller heavier mud tire so more MPG.

Edited by Pearl2017
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TomBrady80 Enthusiast

TomBrady80

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7 hours ago, newdude said:

 

Performance/speed shop.  https://www.procharger.com/      https://www.procharger.com/dealer-locator   It would take some custom work to get the 5.3 kit I'd imagine to work.  We've got a place up here in NY that would be great at making that type of thing happen.  https://www.berg-racing.com/ 

 

Custom tune.  Never out of the box plug in tuner.  BlackBear Performance, or a local LS/LT engine specialist. 

So the out of the box tuners aren’t worth it? I’m sure I’ll have to rely on a experienced tech somewhere to help but I was hoping some of these new plug in programmers were easier to use now. I’ll definitely look into the tuning to E85 and possibly 4.10 gears or 3.73...

TomBrady80 Enthusiast

TomBrady80

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1 hour ago, Pearl2017 said:

A lot of good and bad info I'm hearing. IMO spending thousands on forced induction or gearing to change your stock truck into something it is not is a huge mistake. If you want the bigger engine trade that sucker in and apply those thousands to get what you want. Tuning and CAI is cheap stuff that can wake up a sleepy machine. 6 or 8 speed trannies are the secret sauce that avoids having to do these more expensive add on's. The trans multiplies power and the tune optimizes shifting the available gears to get you there.

 

If you do want to tow be aware a tire with E load rating will handle the load better and I know for michelins can be aired yup to 80PSI if need be to safely carry a load. And they will have less rolling resistance than a smaller heavier mud tire so more MPG.

Right now I have some 275/55/20s. I switched from the small factory 17s hoping to get a better and sportier ride and look. I ended up getting a rougher ride over 70mph on the interstate! I’m definitely opting for a 2.5” leveling kit so when I get some better tires, they don’t rub. I see know that I need a taller tire. My old ram that I used to have was all ready for me with the Hemi and Laramie 4x4 Edition. I’m just chasing some extra HP to get me through a couple of years. 

028ECB78-B7F9-497E-A114-3E9925FE5862.jpeg

98CCF52E-3D2D-4C3B-8A72-E72C4B0D1664.jpeg

TomBrady80 Enthusiast

TomBrady80

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12 minutes ago, TomBrady80 said:

So the out of the box tuners aren’t worth it? I’m sure I’ll have to rely on a experienced tech somewhere to help but I was hoping some of these new plug in programmers were easier to use now. I’ll definitely look into the tuning to E85 and possibly 4.10 gears or 3.73...

There’s a procharger place about 80 miles away in Decatur, Al! I’ll call them up. Thanks

Donstar Senior Enthusiast

Donstar

Posted
Posted
3 hours ago, TXGREEK said:


Absolutely agree

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I once thought that 20's with a 55 aspect would be like wagon wheels until I experienced my daughter-in-law's Yukon XL and my son's High Country both with factory 20's.  I believe premium quality highway tires on 20's will give a nice ride and wouldn't hesitate to have these on my own truck.  Unfortunately, changing tires and wheels is not as simple as  trying on shoes. I was able to try the different sized rims with similar tires on similar vehicles.  If I relied solely on what I read and didn't have this recent experience I too would be anti-20".

TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted
I once thought that 20's with a 55 aspect would be like wagon wheels until I experienced my daughter-in-law's Yukon XL and my son's High Country both with factory 20's.  I believe premium quality highway tires on 20's will give a nice ride and wouldn't hesitate to have these on my own truck.  Unfortunately, changing tires and wheels is not as simple as  trying on shoes. I was able to try the different sized rims with similar tires on similar vehicles.  If I relied solely on what I read and didn't have this recent experience I too would be anti-20".


I’ve got the 16 Yukon XL, wife loves it but did notice harsher ride once I got ride of the factory tires and then put these Michelin Defenders on, they’re 27/55/20. I’d like to change them but what’s a better tire?

dc3bb945b1bcd19534f52f33c81290a4.jpg

My 18 GMC Sierra 6.2 rides on 275/60/20 and rides harsher with new BFG KO2’S. Need the AT’s cause I’m off-road in grassy areas often.

b9d5382ff9beaa2e4b1b2bff1a8bc725.jpg



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TXGREEK Senior Enthusiast

TXGREEK

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Posted

Btw, both vehicles aired at 35 psi


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Donstar Senior Enthusiast

Donstar

Posted
Posted
1 hour ago, TXGREEK said:

 


I’ve got the 16 Yukon XL, wife loves it but did notice harsher ride once I got ride of the factory tires and then put these Michelin Defenders on, they’re 27/55/20. I’d like to change them but what’s a better tire?

dc3bb945b1bcd19534f52f33c81290a4.jpg

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The harsh ride on this combination surprises me.  Good to know as I thought this would be the ideal wheel and tire!  I believe my positive experience on 20's referred to earlier was with Continentals and BF Goodrich highway tires.  I have Defenders on my 17's. 

TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted
The harsh ride on this combination surprises me.  Good to know as I thought this would be the ideal wheel and tire!  I believe my positive experience on 20's referred to earlier was with Continentals and BF Goodrich highway tires.  I have Defenders on my 17's. 

It rode very smooth with the continentals. I’ll let you know once I switch them out.


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TomBrady80 Enthusiast

TomBrady80

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4 hours ago, TXGREEK said:

 


I’ve got the 16 Yukon XL, wife loves it but did notice harsher ride once I got ride of the factory tires and then put these Michelin Defenders on, they’re 27/55/20. I’d like to change them but what’s a better tire?

dc3bb945b1bcd19534f52f33c81290a4.jpg

My 18 GMC Sierra 6.2 rides on 275/60/20 and rides harsher with new BFG KO2’S. Need the AT’s cause I’m off-road in grassy areas often.

b9d5382ff9beaa2e4b1b2bff1a8bc725.jpg



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They look good! My offset may be throwing it off some though. I’d like a taller tire like that.

6FD513AF-2FA2-4B06-A6F5-5F0A236113F7.jpeg

EBC1ACA1-55C5-463A-B73F-39ABAEABEFC9.jpeg

TomBrady80 Enthusiast

TomBrady80

Posted
  • Author
Posted
8 hours ago, TXGREEK said:

 


Looks is what gets everyone into hating their ride. My truck came w 22”’s, had dealership downgrade to 20”s then had to order new rims, made the mistake going back to 20”’s cause they look good but wish I had gone to 18”’s just more side wall would give me smoother ride and more sidewall protection too. 20”s tow less too.


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Thanks! Yeah once I hit 70mph the truck is shaking so bad..... 

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