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The RedBurb

Every Part Is Replaceable
Yes, you have a 1/2-ton emissions intake manifold ("C-code"). The picture below shows what a dual-plane non-emissions J-code manifold looks like. These were used on 3/4-ton and 1-ton trucks. The opening is larger, and these are air-limited engines. I noticed a difference when I swapped out my C-code manifold.


maxresdefault.jpg



These two cover most 6.2 trucks, but there are a few more intake manifolds used on these engines (6.5TD manifolds are a bit different on top to accommodate the turbine plenum). @AgDieseler has at least half of them hanging on his wall... ;)

So it’s probably not as simple as removing the EGR valve, is it? Need to replace the whole manifold?
 
So it’s probably not as simple as removing the EGR valve, is it? Need to replace the whole manifold?
The improved torque and throttle response is worth the effort.

And yes, I have most of the 62/6.5 intake manifold variants hanging on my wall, save for the weird van/M998 piece. I should probably hunt one down.

David
 
The improved torque and throttle response is worth the effort.David

Then that’s a yes, replace the intake manifold, sounds like. From what I’ve read seems like the hmmv ones are the best to go after. Just surprised because from what other people told me on other forums, I already had a J code intake. Oh well.
 
Go J code - much simpler than the hummer intake, and your air filter will bolt on.

David

Here’s the info I was given elsewhere a while back, if y’all disagree that’s fine, just wanting clarification:

“Judging by the distance between the rear of the IP and the intake, and the height/angle of the runners, it is a "J code" single plane. Much easier to know, by looking at the inside under the air inlet cover. We never did a post with the differing intakes and the corresponding parts #'s, might be a good work project for the winter, as we have 5 different OEM manifolds here (think there are 7, including military)....J&J.


BTW, yours is a rare manifold, with the DD spinning arrows.....:thumb::thumb:

FF3007DD-C46B-45D9-8833-07440F2970BC.png


Is it POSSIBLE that this IS a J code intake and some PO installed the EGR valve when swapping the 6.5 into the truck?
 
Here’s the info I was given elsewhere a while back, if y’all disagree that’s fine, just wanting clarification:

“Judging by the distance between the rear of the IP and the intake, and the height/angle of the runners, it is a "J code" single plane. Much easier to know, by looking at the inside under the air inlet cover. We never did a post with the differing intakes and the corresponding parts #'s, might be a good work project for the winter, as we have 5 different OEM manifolds here (think there are 7, including military)....J&J.


BTW, yours is a rare manifold, with the DD spinning arrows.....:thumb::thumb:

View attachment 293304


Is it POSSIBLE that this IS a J code intake and some PO installed the EGR valve when swapping the 6.5 into the truck?

Just answered my own question, went out and looked inside the intake manifold and it’s obvious that the EGR is not something that is just swapped in. It is a part of the casting of the manifold. Speaking from ignorance again! Sorry about that. On the hunt now for a J code intake manifold.

5241BD0B-5D93-493D-8066-8F71CCA46F57.jpeg
 
On my 6.2 I had my egr valve disconnected so it did not function. Recently I made longer air filter studs to run my air cleaner lid flipped for more air flow and since the studs also hold the egr valve in I whipped up a quick egr block off plate out of the old egr valve and got rid of the egr valve altogether. https://ck5.com/forums/threads/83-k...es-rear-discs-boring-but-works.324516/page-25

That’s a great alternative. I’ll read over your link more and will probably go for it
 
Just answered my own question, went out and looked inside the intake manifold and it’s obvious that the EGR is not something that is just swapped in. It is a part of the casting of the manifold. Speaking from ignorance again! Sorry about that. On the hunt now for a J code intake manifold.

View attachment 293305
I have one ready to go and a couple still on engines I am parting out.
If you want it pm me
 
Here’s the info I was given elsewhere a while back, if y’all disagree that’s fine, just wanting clarification:

“Judging by the distance between the rear of the IP and the intake, and the height/angle of the runners, it is a "J code" single plane. Much easier to know, by looking at the inside under the air inlet cover. We never did a post with the differing intakes and the corresponding parts #'s, might be a good work project for the winter, as we have 5 different OEM manifolds here (think there are 7, including military)....J&J.


BTW, yours is a rare manifold, with the DD spinning arrows.....:thumb::thumb:

View attachment 293304


Is it POSSIBLE that this IS a J code intake and some PO installed the EGR valve when swapping the 6.5 into the truck?


The easier way to see that it's a single plane is.............it has a single plane.

No measurements required. :waytogo:
 
My observation from side by side examinations of my MP4 and MP5 intake manifolds is that they're the same, minus the extra machining for the secondary fuel filter (missing from the later manifold). I don't think there was any benefit whatsoever to using the military manifold when comparing apples to apples. Those guys are comparing different styles of manifold. That's where the gains come in.
 
That’s a great alternative. I’ll read over your link more and will probably go for it

The goal isn't to ditch EGR. You've already done that twice over by blocking the ports and disconnecting the solenoid. You want to get rid of the reduction in cross-sectional area where the air is entering the manifold. And that's part of the casting. These engines are air-limited, and getting rid of the obstruction is the goal. If you're not doing that I wouldn't bother with blocking the port and ditching the actuator. With the stock air cleaner the actuator is fairly high and somewhat out of the way. It's not the primary flow restriction.

A good mill could probably cut that center divider out of there. Then you'd approximately have a single plane C-code manifold, the only one on earth!
 
Go J code - much simpler than the hummer intake, and your air filter will bolt on.

David

Side note.... The center bolt holes on a 6.5 manifold are the same as the 6.2 air cleaner holes. The mounting surface is about 3/8" lower. But if you slightly clearance where the stock air filter housing touches the IP, you can run a 6.5 manifold on a 6.2 quite well.

I have pictures buried in a build thread somewhere... :rolleyes:
 
Here’s the info I was given elsewhere a while back, if y’all disagree that’s fine, just wanting clarification:

“Judging by the distance between the rear of the IP and the intake, and the height/angle of the runners, it is a "J code" single plane. Much easier to know, by looking at the inside under the air inlet cover. We never did a post with the differing intakes and the corresponding parts #'s, might be a good work project for the winter, as we have 5 different OEM manifolds here (think there are 7, including military)....J&J.


BTW, yours is a rare manifold, with the DD spinning arrows.....:thumb::thumb:

View attachment 293304


Is it POSSIBLE that this IS a J code intake and some PO installed the EGR valve when swapping the 6.5 into the truck?

I am a bit cornfused. The manifold pictured here is NOT the one you pictured recently. Do you have two of them?


And it's too bad Martin isn't around here anymore. I'd love to get his reaction to seeing Detroit Diesel arrows cast into a 6.2 part. And Detroit green, no less!





"It's not a Detroit.
Martin."

:haha: :rotfl:
 
I am a bit cornfused. The manifold pictured here is NOT the one you pictured recently. Do you have two of them?


And it's too bad Martin isn't around here anymore. I'd love to get his reaction to seeing Detroit Diesel arrows cast into a 6.2 part. And Detroit green, no less!





"It's not a Detroit.
Martin."

:haha: :rotfl:


No sir that was a sample photo someone sent me to show the similarities to my intake. ;)
 
Are these in better shape than yours?

Yessir they are. They need to be doctored up (some goober painted them white with house paint), but the sheet metal is solid. Mine are rusted out at the bottom and falling apart (not even worth fixing). Plus they were only $200 for all 4 of them so ...

The middle row seat is also in really great shape and matches the rest of the seats, as compared to what I currently have which is a mixed matched tan and blue middle row seat. Always been an eye sore and always bothered me.
 
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