Intake manifold swap?

[Jon A]

I think you just made that all up

 

Wow. Seriously? And here I've been feeling guilty about not spending enough of my very, very, very valuable time here contributing information many would find very valuable. Spend a little time doing that and this is the thanks I get....

 

That's OK. In my abundance of free time I was able to figure out how to log into wifi with my photographic memory so you can share in all I imagined!

 

There was this:

 

 

and this:

 

 

and:

 

 

and:

 

 

 

 

and last but not least my real wet dream!

 

 

 

 

A few of these too!

 

 

I actually have more than that but you can only fit so many dynos on one sheet.... Such an imagination....

 

 

Nobody thinks that the difference between the lt1 and l86 is just in the intake manifold.

 

Actually lots of people do think exactly that. There have been many conversations about it here and elsewhere the last four years. Since the intake manifold is the only major powercurve affecting difference between the shortblocks, that was the natural thing to think. 1/2 the people here will tell you catbacks and CAI's won't gain you any power ("all they add is noise, etc"), so it had to be the intake manifold, right?

 

 

 

We think it's the intake AND exhaust manifold.

 

Who is "We?" I guess I missed the memo. I don't think I've ever seen any discussion of the LT1 exhaust manifold (which one?) here as making a meaningful difference. A better question would be, who cares? If a couple of the ponies are coming from the exhaust manifolds and not the better cat-backs...who cares? The point is those are HP not coming from the intake manifold.

 

 

I will eat my words if you post up your "data" showing the primary hp difference between the two engines is before the intake manifold and after the exhaust manifold, just as you stated.

 

 

I stated the data pertained to the air intake system. Attached you will find a scan from a stock Camaro on the dyno. If you look at the MAP values, you can see it only pulls 3-3.5 kPa of vacuum from beginning to ~6K RPM, depending upon the exact RPM ranges over which you take your averages. That's as good as the trucks will do with an aftermarket CAI. With the stock system, the trucks will pull 5.5-6 kPa of vacuum.

 

If you do the math, that's a solid 10-12+ HP the air intake system alone is worth. Add somewhere around that much for a better exhaust system, and you realize most of the 35 HP difference isn't coming from the intake manifold. Even more importantly, the manifolds are not equal in the midrange torque they produce.

 

The L86 manifold is head and shoulders above the other two in the midrange. That won't matter much when racing once you're out of first gear (especially with an 8-speed), but for a truck doing truck things it is a difference to note.

 

If GM put the truck manifold on a Camaro, it would not be rated 420/460 as many would assume. It would be more like 440/480...or what you'd expect on a truck with a CAI and a catback. Like I said....

 

 

EDIT: I guess it won't let me attach an .hpl file. I'd be happy to email it to anybody who wants it.

[truckguy82]

I just want to see the data

 

You can probably convert it to .jpg

[truckguy82]

What is that dyno graph of? It's just a bunch of lines with no information pertaining to what is what

[ruby15z71]

 

Wow. Seriously? And here I've been feeling guilty about not spending enough of my very, very, very valuable time here contributing information many would find very valuable. Spend a little time doing that and this is the thanks I get....

 

That's OK. In my abundance of free time I was able to figure out how to log into wifi with my photographic memory so you can share in all I imagined!

 

There was this:

 

 

and this:

 

 

and:

 

 

and:

 

 

 

 

and last but not least my real wet dream!

 

 

 

 

A few of these too!

 

 

I actually have more than that but you can only fit so many dynos on one sheet.... Such an imagination....

 

 

 

Actually lots of people do think exactly that. There have been many conversations about it here and elsewhere the last four years. Since the intake manifold is the only major powercurve affecting difference between the shortblocks, that was the natural thing to think. 1/2 the people here will tell you catbacks and CAI's won't gain you any power ("all they add is noise, etc"), so it had to be the intake manifold, right?

 

 

 

 

Who is "We?" I guess I missed the memo. I don't think I've ever seen any discussion of the LT1 exhaust manifold (which one?) here as making a meaningful difference. A better question would be, who cares? If a couple of the ponies are coming from the exhaust manifolds and not the better cat-backs...who cares? The point is those are HP not coming from the intake manifold.

 

 

 

 

I stated the data pertained to the air intake system. Attached you will find a scan from a stock Camaro on the dyno. If you look at the MAP values, you can see it only pulls 3-3.5 kPa of vacuum from beginning to ~6K RPM, depending upon the exact RPM ranges over which you take your averages. That's as good as the trucks will do with an aftermarket CAI. With the stock system, the trucks will pull 5.5-6 kPa of vacuum.

 

If you do the math, that's a solid 10-12+ HP the air intake system alone is worth. Add somewhere around that much for a better exhaust system, and you realize most of the 35 HP difference isn't coming from the intake manifold. Even more importantly, the manifolds are not equal in the midrange torque they produce.

 

The L86 manifold is head and shoulders above the other two in the midrange. That won't matter much when racing once you're out of first gear (especially with an 8-speed), but for a truck doing truck things it is a difference to note.

 

If GM put the truck manifold on a Camaro, it would not be rated 420/460 as many would assume. It would be more like 440/480...or what you'd expect on a truck with a CAI and a catback. Like I said....

 

 

EDIT: I guess it won't let me attach an .hpl file. I'd be happy to email it to anybody who wants it.

 

What are the runs in the dyno graph? Is this all with a 5.3L L83 swapping the intake manifolds? What other mods are on this motor?

[jrob56]

What are the runs in the dyno graph? Is this all with a 5.3L L83 swapping the intake manifolds? What other mods are on this motor?

 

Well you can see in the pictures all are with headers, AFE cold air, plug wires.Guessing nothing beyond that besides some catback.

 

Cant tell if 5.3 or 6.2. Intake is usually the tip off. Id guess 5.3 or we wouldnt be talking about swapping the 6.2 truck intake manifold on.

[07Softail]

 

Well you can see in the pictures all are with headers, AFE cold air, plug wires.Guessing nothing beyond that besides some catback.

 

Cant tell if 5.3 or 6.2. Intake is usually the tip off. Id guess 5.3 or we wouldnt be talking about swapping the 6.2 truck intake manifold on.

Those power numbers are clearly 6.2 at the wheels!

 

RT

[wuznme]

6.2 - check the catch can hose routing.

[wuznme]

if anybody with a 5.3 is interested will have 6.2L intake manifold and throttle body for sale in 2 weeks.

[07Softail]

Hahaa I have had mine for sale for a while now. What throttle body are you going with?

 

RT

[wuznme]

Either having Tony port one or the Katech 103MM; haven't decided yet.

[jrob56]

6.2 - check the catch can hose routing.

That doesn't apply if you switch a 5.3 to the 6.2 intake manifold... it would then have the catch can routing of a 6.2.

 

Like softtail said, numbers seem like 6.2 though, that was a good catch.

[07Softail]

Well that and Jon A's truck has a 6.2

 

RT

[shift_grind]

Any idea on what a 5.3 would gain if switched to the 6.2 intake manifold and throttle body?

 

Seems like a stock looking bolt on afair that wouldn't raise any red flags at the dealership.

[07Softail]

It will give you a 100 HP and around 120 Ftlbs! LOL JK!!!! BTW I have a 6.2 Manifold for sale!

 

RT

[ruby15z71]

Any idea on what a 5.3 would gain if switched to the 6.2 intake manifold and throttle body?

 

Seems like a stock looking bolt on afair that wouldn't raise any red flags at the dealership.

It is a simple bolt on job and only way they would know isnif they plug in the tech2 and run a diagnostic to see it's been tuned. Also if the tech is smart he'll notice the throttle body and factory/cai connection is a bit bigger. I have an aFe momentum GT cai and it comes with a reducer coupler to Attach the throttle

Body to the intake. That's only way they'd find out.

 

As for the power it can give, I've seen about 15-30hp tuned (depends on da and dyno you're on or track times) which isn't bad for only spending $250 roughly. The MSD intake manifold is about a grand and will maybe net 10-15 hp more but also requires you to change out the upper pulley so it actually comes out to like 1200 + the tune.