Anyone upgraded to intake manifold from 6.2 to 5.3

[jaxscuby]

I have seen youtube videos on swapping intake manifold from 6.2 with larger throttle body to 5.3.

Anyone done this yet?

 

[Marky Dissod]

Opening your mouth and/or nostrils wider will not meaningfully improve your cardio (although I suppose Julia Roberts can still take unusually large bites of food).
By the same token, a larger throttle body on an engine with the same cam & heads and valves and tune, will make little to no difference.
If the 6.2L throttle body is larger than the 5.3L throttle body, the 5.3L throttle body MIGHT be restrictive on the 6.2L,
but it does not follow that the 6.2L throttle body would improve the 5.3L's performance.

More importantly, if there is ANY commonality whatsoever between how engine tunes work now and how they worked in the 90s,
this will wear out the transmission more quickly.

In other words, if you're going to put a 6.2L throttle body on a 5.3L, you better tune the ecm for it when you do.

 

[Joseph Garcia]

^^^^^x2^^^^^ @Marky Dissod is spot on with his reply. If that is the only mod that you are considering in the scope of this project, you won't get anything meaningful out of it.

If you want to squeeze a bit more out of your 5.3, talk to @BlackBearPerf about a tune.

 

[Basecamp]

I have seen youtube videos on swapping intake manifold from 6.2 with larger throttle body to 5.3.

Anyone done this yet?

Yes, just did that 2 weeks ago. I went this route- Genuine GM L86 Intake Manifold 12639087 which mates perfectly to the aFe POWER 87mm Throttle Body 46-39109.
The TB is connected to an aFe Momentum GT Cold Air intake Part Number 51-74110. The plastic GM manifold is a great deal compared to all the rest, especially if you have supercharger dreams and might toss it in favor of a magnuson some day.

 

[jaxscuby]

did you have to have maf table revised for the larger throttle body?

in other words..tuning involved?

 

[Doubeleive]

it's a thing people do it, it's a relatively cheap small upgrade. I have thought about doing it, if i did I would buy one that has been ported already and of course get the tune adjusted at the same time.
I am leaning more towards just replacing the engine with a 6.2 though and then changing the front diff and rear carrier to 3.42
the transmission is the same in either case 5.3/6.2 what they change is the axle ratio.
and I am guessing some of that has to do with the sweet spot between engines.
5.3L (L83/L84): 1,500 – 1,800 RPM
6.2L (L86/L87): 1,400 – 1,700 RPM
the 6.2 has more low end torque, actually more overall torque and hits peak at a smidge higher rpm

 

[Basecamp]

did you have to have maf table revised for the larger throttle body?

in other words..tuning involved?

Yes, I did. I have the MPVI3 and tuned it. Installed the Kooks long tubes and green catted ypipe at the same time. Also full LT4 and E85 fueling. Max NA gains but I have to wait till summer for the good E85.

 

[OR VietVet]

So....I gotta ask....WHY?
Too much extra money?
Go for it....I guess!

Plus, your thread title says 6.0, not 6.2....
C'mon man!!!!!

 

[jaxscuby]

the youtube videos of dyno runs without tuning showed +10whp & more torque.

The manifold is about $160 & throttle body $70, orings $20 for intake & throttle body.

so for less than $300 increase in power. but they did not report on daily mileage gains.

spent way more than $300 when I had my 65 Mustang on manifold & carb.

 

[Joseph Garcia]

the youtube videos of dyno runs without tuning showed +10whp & more torque.

The manifold is about $160 & throttle body $70, orings $20 for intake & throttle body.

so for less than $300 increase in power. but they did not report on daily mileage gains.

spent way more than $300 when I had my 65 Mustang on manifold & carb.

So, for $300, you get an approximate 3% increase in horsepower. It is certainly not costly for sure, but do you think that you will even feel that difference?

Hey, I get it, if you love to wrench and have spare money lying around, then go for it.

 

[Basecamp]

Yes, I did. I have the MPVI3 and tuned it. Installed the Kooks long tubes and green catted ypipe at the same time. Also full LT4 and E85 fueling. Max NA gains but I have to wait till summer for the good E85.

And… that GM L86 intake I installed on my L83 3 weeks ago is going to have to come off in a month or two. I had a mental break and ordered the Magnuson TVS2650 for L83 5.3 today. This “better to die with memories than dreams” thing is going to kill me.

 

[LSCALADE]

While all these mods make you feel good about the money spent, the best advice I can give anyone is to do a stage "0" reset, all new fluids, spark plugs, filters and fuel system clean. My Suburban runs so much better now than it did 1mo ago when I bought it and that is money spent that I can feel every day when I drive it.
On my average commutes, I barely ever get over 2200-2400rpm so if I can't feel the 10hp at 6000rpm then its money wasted in my book.

Say we line up at a traffic light and we have a wide open road where we can get up to 70-80mph and both trucks take off at the same time. How much farther do you think the truck with the 6.2L intake manifold will get by say 1/4 mile down the road?

 

[ReaperHWK]

Who is racing these big ass trucks anyway?! lol. Line up the Tahoe?

I have a 2026 RST with the 6.2 and performance package, it’s slow as balls to any real vehicles that are considered fast. My other ride has twice the HP and weighs half as much, so driving this Tahoe is like driving a bloated school bus.

It does look/sound nice though. But it’s not a race car!

I don’t understand these modifications to increase “performance” on these things. You guys running top speed events and getting 1/4 mile runs in the single digits? Lol.


Here is an extreme example. Hennessy H600:

NEW Supercharged H600 Chevrolet Tahoe and Suburban | Dyno Testing | 600 HP

In this video, we strap the Hennessey H600 Chevrolet Tahoe to the dyno to measure just how much power it's putting down.

www.hennesseyperformance.com

That runs 13.5 1/4 and a 5.3 0-60.

A Honda accord will run a 13.9 1/4 mile and 5.5 0-60.

So that modified Tahoe will get a run for its money with a STOCK accord.

 

[OR VietVet]

Except at a drag strip, give me a stock reliable 5.3, like my GMT800, and set up the tires, steering and suspension and stand by for some fun on any roads.

 

[Marky Dissod]

Who is racing these big ass trucks anyway?! lol. Line up the Tahoe?

I have a 2026 RST with the 6.2L and performance package, it’s slow as balls to any real vehicles that are considered fast.
My other ride has twice the HP and weighs half as much, so driving this Tahoe is like driving a bloated school bus.
It does look/sound nice though. But it’s not a race car!

I don’t understand these modifications to increase “performance” on these things. You guys running top speed events and getting 1/4 mile runs in the single digits? Lol.

Here is an extreme example. Hennessy H600:

NEW Supercharged H600 Chevrolet Tahoe and Suburban | Dyno Testing | 600 HP

In this video, we strap the Hennessey H600 Chevrolet Tahoe to the dyno to measure just how much power it's putting down.

www.hennesseyperformance.com

That runs 13.5 1/4 and a 5.3 0-60.
A Honda accord will run a 13.9 1/4 mile and 5.5 0-60.
So that modified Tahoe will get a run for its money vs a STOCK Honda Accord.

(It'll also get a run for its money against a conscientiously modded mid-90s Caprice or RoadMaster with an LT1 - if the Caprice/RoadMaster doesn't fall apart ...)

Now that I think about it, I seem to notice at least one glaring omission from the H600's mod list:
How come they don't bother to improve the axle gearing?

 

[ReaperHWK]

(It'll also get a run for its money against a conscientiously modded mid-90s Caprice or RoadMaster with an LT1 - if the Caprice/RoadMaster doesn't fall apart ...)

Now that I think about it, I seem to notice at least one glaring omission from the H600's mod list:
How come they don't bother to improve the axle gearing?

I had an LT1 once……

 

[LSCALADE]

Best bang for the buck I have found is lighter wheel and tire option. Dropping down from a 22" to a 18" or even a 20" does wonderful things to the way the heavy truck feels. Brakes become stronger, steering becomes lighter, accelaration and corerning benefit. I think a set of light wheels is worth its weight in gold compared to any power adders.

I went from 20" Wagoneer wheels to a 20" PPV Steel wheel and the difference is staggering. Adding unsprung mass has me questioning why I did this. I will be going to a 18" set up soon. The cushy ride with thicker tire is also a nice bonus.

 

[Joseph Garcia]

Who is racing these big ass trucks anyway?! lol. Line up the Tahoe?

I have a 2026 RST with the 6.2 and performance package, it’s slow as balls to any real vehicles that are considered fast. My other ride has twice the HP and weighs half as much, so driving this Tahoe is like driving a bloated school bus.

It does look/sound nice though. But it’s not a race car!

I don’t understand these modifications to increase “performance” on these things. You guys running top speed events and getting 1/4 mile runs in the single digits? Lol.


Here is an extreme example. Hennessy H600:

NEW Supercharged H600 Chevrolet Tahoe and Suburban | Dyno Testing | 600 HP

In this video, we strap the Hennessey H600 Chevrolet Tahoe to the dyno to measure just how much power it's putting down.

www.hennesseyperformance.com

That runs 13.5 1/4 and a 5.3 0-60.

A Honda accord will run a 13.9 1/4 mile and 5.5 0-60.

So that modified Tahoe will get a run for its money with a STOCK accord.

You know, to each their own. I own a truck, and I LOVE to performance mod it. My truck, my choice, and nobody has to understand. And, that is cool, as we all have our own desires and opinions.

And, everything is relative. The example of the 'performance' Hennessy is still a turtle, compared to a Bugatti. Who cares?

That's the beauty of a free country. We get to do what we want with our vehicles, within our own budgets, and sometimes the law, and nobody else needs to understand or care.

Here's a little secret..... I have a truck modded for performance, because I like smiles per mile. But, I also KNOW, that at 73 years of age, if I had a car modded for performance, I'd probably kill myself in it, while getting smiles. My truck offers me some protection against becoming a fatality while smiling.

And, I have 2 White German Shepherds who demand to go with me everywhere I go, and the truck affords me the opportunity to satisfy their desires.

For me, it's a win-win.

Just my 2 cents worth.

 

[Boston]

Opening your mouth and/or nostrils wider will not meaningfully improve your cardio (although I suppose Julia Roberts can still take unusually large bites of food).
By the same token, a larger throttle body on an engine with the same cam & heads and valves and tune, will make little to no difference.
If the 6.2L throttle body is larger than the 5.3L throttle body, the 5.3L throttle body MIGHT be restrictive on the 6.2L,
but it does not follow that the 6.2L throttle body would improve the 5.3L's performance.

More importantly, if there is ANY commonality whatsoever between how engine tunes work now and how they worked in the 90s,
this will wear out the transmission more quickly.

In other words, if you're going to put a 6.2L throttle body on a 5.3L, you better tune the ecm for it when you do.

LOL… I have a bloody nose!

 

[ReaperHWK]

You know, to each their own. I own a truck, and I LOVE to performance mod it. My truck, my choice, and you don't have to understand. And, that is cool, as we all have our own desires and opinions.

And, everything is relative. Your example of the 'performance' Hennessy is still a turtle, compared to a Bugatti. Who cares?

That's the beauty of a free country. We get to do what we want with our vehicles, within our own budgets, and sometimes the law, and nobody else needs to understand or care.

I'll let you in on a little secret..... I have a truck modded for performance, because I like smiles per mile. But, I also KNOW, that at 73 years of age, if I had a car modded for performance, I'd probably kill myself in it, while getting smiles. My truck offers me some protection against becoming a fatality while smiling.

And, I have 2 White German Shepherds who demand to go with me everywhere I go, and the truck affords me the opportunity to satisfy their desires.

Just my 2 cents worth.

Hey man whatever makes you happy. I get it.

I was just saying that someone stated “lining them up” in regards to racing these trucks. My point is in regards to that, you’re not going to be winning any pink slips lol.

You’d need a 2000hp Tahoe to keep up with a stock hellcat……. It’s not a “racing” platform.

I love my 6.2L Tahoe with performance package. It’s nice and can keep up with traffic. For me it feels very slow though. It really falls flat after 3000rpm and any speeds over 50mph it won’t get out of its own way. But it’s fun as it sounds nice and has a little low end grunt.

I’m used to pulling my “fast” car to these speeds so you can understand my comparison: