C-code intake manifold to HMMWV intake manifold swap questions

[AJMBLAZER]

I recently got a great deal on a 6.2L HMMWV intake manifold. Searched around on here and pretty much got the impression that other than your intake lid being 90 degrees different orientation than before it was A-ok as a swapping candidate from the stock C-code intake on my '89 6.2L .

I've run in to two problems so far that have stopped my effort.

-The CDR hose fitting on the C-code intake and on my CUCV's J-code intake is big, like 3/4" or so. The HMMWV intake fitting is much smaller, 1/2" or so. I'm thinking I can just get some hose and an 3/4"-1/2" adapter to fix this. A bit annoying but would this cause any trouble?

-While researching this over the phone for me my buddy ran into a reference that since the HMMWV / Hummer intake sits so much lower than the truck intakes the stock air cleaner won't clear the IP. Is this true? Anyone had to get around this? He said the guy vaguely mentioned making a spacer or something.

Frustrated. Another project of mine turns to a steaming pile. Gotta go back outside and put the original stuff back together.

[john8662]

Darn,

Yeah, the Hummer intake isn't a bolt-on deal for sure.

I've got one too and observed the same thing, just in looking at it though.

The right part can be had pretty easily, pretty sure that Diesel Depot has more than enough of the style you need. You need the 6.2/6.5 single plane intake, really common. I think I can come up with one through this route too if needed.

And a later 6.5'er n/a intake will work because you're not dependant on the fuel filter mounting to the back of the intake manifold with the FM80 filter. The FM100 filter mounts differently (round one used on the 6.5TD's and NA's).

J

[AJMBLAZER]

I'd kind of like to make this one work since I have it and I doubt I can get the guy to take it back. Money's tight.

Think the CDR outlet being so small would cause trouble?

I've had a number of suggestions to just make a spacer for the stock air filter housing. Going to talk to my buddy who's Mr Fab-it about this.

What's the Diesel Depot?

[john8662]

Diesel Depot is an engine remanufacturer that does a lot of these engines, and has a lot of parts. Google 'em.

I can't say on the ability of the smaller port to work, it probably will. Find a picture of the CDR system on a 6.2L H1 and maybe that will answer how it works.

I'd think it would work though, just your 6.2 takes it's blow-by off the valve cover, and I think an H1 is off the oil filler tube like previous 6.2's did.

[AJMBLAZER]

Yeah, I found them later last night. Thanks. They have a decent price on J code truck intakes, $75 plus shipping. I might still go that route through them. Surprised me when Jamie there emailed me at 6:30pm EST.


I was talking with my buddy that knows a thing or three about these 6.2L's and he doesn't think much of the CDR tube being smaller either. Not like these pull a vacuum or anything.

[Robyn]

Drill the plenum on the Hummer manifold and tap it with a pipe tap so a proper sized fitting will screw in.

Not a real issue at all.

You can modify whichever side of the plenum area that you ned to in order for your factory CDR to hook up.

I have done this for a couple folks.

Wont take very long to do, especially with tha manifold off and easy to access.

As far a s the filter hitting the IP ????????// Seems that the Hummer has a special top hat that bolts on and the filter is remote mounted.

Scrounge the Bone yards and find an air filter spacer off a chevy pickup, HMMMMM 350 Gassers of several years had these spacers.

I think the one that fits a quadrajet is the right size.

If not make a spacer thats just tall enough to work. You might have to mess with the length of the retaining studs that hold the filter on though.

Minor little stuff but easy to remedy.

Robyn

[AJMBLAZER]

Hah...junkyards around here having anything with a carb in them? HAH! They scrapped anything older than the 90's body styles a few years ago when scrap prices shot up. Makes getting parts for my trucks hard. I'll be gone soon enough though.

I remember my '92 K1500 had a spacer on it's 350 TBI but I'm sure it wasn't 6" or so wide like this is.

Derp, can't believe I didn't think of drilling and tapping it.
Is the original fitting thing pressed in there? That's what it looks like.

[Robyn]

I do believe the fittings were a press in. No matter, horse out whatever is there, drill and tap the hole for a barbed fiitting to suit and your set.

Make a spacer using a piece of suitable aluminum pipe or even ABS or PVC would work great. Just be sure the faces are straight so the gasket will seal.

Gotta get creative.


Robyn

[DmaxMaverick]

....Or, go to Jegs or Summit and pick up an intake riser spacer. They have all height sizes, and the 6.2L inlet isn't an oddball dia. (5.125", IIRC??). And, they're cheap (less than $10, or really up there if you want billet aluminum). The stud can be replaced with some all-thread (use Loc-Tite).

[AJMBLAZER]

Make a spacer using a piece of suitable aluminum pipe or even ABS or PVC would work great. Just be sure the faces are straight so the gasket will seal.

Robyn

Gasket? Is there supposed to be a gasket under this thing?

I'll have to check at Summit, thanks!

[AJMBLAZER]

Off hand anyone have any idea how tall of a spacer I'd need?

[john8662]

The 6.2L Vans had a spacer for the intake manifold that would probably do the trick here just fine and you could use the Van Studs for the intake.

It does use two gaskets, two of the cardboard looking gaskets. Anything you'd buy would too. I'm using buna rubber gaskets that I had made...

Good idea above to drill out the intake, but only after you figure out a good way to get out the fitting in the existing intake. They're a press-in design.

[AJMBLAZER]

Problem I'm running into is there doesn't seem to be a 6.2L van in a 'yard within a 3 hour drive of my location or my friends downstate...even LKQ has nothing. Probably have to get something from Summit.


So...anybody got a clue on how tall the spacer should be?

Funny part is I'm eyeball deep in buna rubber o-rings and washers every day...have hundreds of pounds of them...sadly not a single one of them wider than 1.5" though.

[EWC]

I've got a J code intake that I'd like to sell . PM me if interested .

[AJMBLAZER]

Well, all the intake spacers I could find on Summit were 5 and 1/8". The HMMWV intake is 5 and 7/8" across at the lip. No go.

Think I'm just going to scrap this thing and get EWC's truck intake. By the time I make this thing work I could have just bought his, bolted it on, and been done.

Anybody want a HMMWV intake for cheap?

[85-m1028]

here's what I did with my single plane.



I bought some sheet rubber at the depot and made a gasket for it by using the oily surface of the manifold for a template.



this is just abs stuff I got at home depot, it worked great for the last couple of years I owned the truck.. If you use 6" abs the I.D. will fit pefectly.

[AJMBLAZER]

Eh, like my stock civie cold air setup.

[handcannon]

Well, all the intake spacers I could find on Summit were 5 and 1/8". The HMMWV intake is 5 and 7/8" across at the lip. No go.

Think I'm just going to scrap this thing and get EWC's truck intake. By the time I make this thing work I could have just bought his, bolted it on, and been done.

Anybody want a HMMWV intake for cheap?

If you decide to sell the HMMWV intake I'd be interested if the shipping isn't too much to get it to Oregon.

Don

[AJMBLAZER]

handcannon, you will have a PM very shortly.

[AJMBLAZER]

Errr, looks like you can't get PM's yet.


Send me an email at my screen name on here with @yahoo.com after it.

Post on here when you do. Thanks.