Mopar 337 intake info and pics here.

Not alot of info out there on this intake, I got one and compared it to my M1 RB 4150 single plane and thought I would post the info. The 337 is a 4150 flange single plane for RB with Max wedge sized ports with a cast in valley pan. While it is billed as Max Wedge size ports they are far undersize. This should allow them to be used on std. port heads with some port work. It it shorter then the std. M1 intake and is around $260.

As cast port sizes, Max Wedge should be around 2.63 x 1.35

Std. gasket

It is about 1/4 shorter at front and 3/8 shorter at the rear of the carb flange.

Carb flange is straight not tilted like the Std. M1

Plenum

Std. M1 plenum

Rough measurement of how much the intake ports on a Std. port Trick Flow head will need to be opened up to work with this intake. To the outside of the markings, Should be around a 2.47 x 1.32 port opening.

The 337 is a really good intake. It solves a problem that no other intake solves and it works a lot better than it looks. I made 800 hp with that intake on my old 505. That was out of the box, I'm sure it would've picked up another 25 hp or more if it had been port matched.

http://www.hotrod.com/how-to/engine/mopp-1206-project-505-the-final-chapter/

I have a ported 337 on my 517, works great

Is this intake available again?

I thought it was unobtainable a few months back...

I just got this one last week from my local Mopar dealer. Summit and Jegs showed it on back order. I had it in 3 days from the dealer and they said there were 3 more left in the system at that time.

Interesting info & pics.

It would probably take some serious grinding and Belzona to make a '337' work for me, but it looks cool.

It is one of the best BB intakes made

It's one of the best intakes no one uses. I have one on a 440 with MW Performers and it runs great. Good price and the built in valley tray is a big plus.

It also makes for a nice fit on a Low Deck with Stage VI heads

I wonder if the TF heads would pick up any flow by making them the size of that manifold.
There is certainly plenty of meat on the head to go that big(or even out to full MW size).

Mmmmmmm, not so much I think.

The bigger question in my mind would be, how well does it work on a 440-470ci street strip combo?
493+ I'm sure it's good...... Might be a tad big on a 440-470(depending on the rest of the combo of course).

I had commented before that as delivered the ports are about 1/2 way between 906 and true Max Wedge, I really think they did this on purpose ( or maybe, knowing Ma MoPar) probably more a 'fortunate accident'....for a change.

What's key to this manifold is the awesome taper ratio from the plenum to the port, great for Horsepower although lower end torque may be down a tad vs say a traditional M1 off idle on a 440-470" motor.

I'd love to see someone try it.

It's a little unsightly with the extra bosses and such on it too......I'd have to trim that stuff off if I were going to actually run it in my car.

Guess they're for mounting an Econorail scoop, lol

I don't mind the injector bosses though.

That really would be a good boss to drill and tap for a scoop pan or wire looms. Hmmmmmmmmmm small gears in brain turning. lol

I'd suspect it would be prone to having a big dip in the torque curve below the torque peak, similar to what the ported Stage VI 4150 intake showed when dynoed with my old Stage VI heads. Probably pull hard up top, though.

I had a similar thought. There is a lot of material on the top side of the ports in the TF heads so I think it could be done. Not sure if it would improve flow or not, I suppose it depends how skillfully the port was reshaped.

Another idea (more work of course) would be to use the 337 intake to make a "high port" TF head. Match up the head to the top of the intake runner and then fill in the bottom of the ports to keep the runner volume at 240 cc. I think that would work really well but it would be expensive to build and probably fairly fragile.

Hypothetically... If I wanted to spend the $$$ for one of these to sit on my shelf for a few years and gather dust, where is the best source to acquire one?

Your local Dodge dealer should be able to round one up for you. Free shipping too.

Might want to check with double00joe, I think he might have one......which I believe be got right from MP.

Is there a lowdeck version of the 337?

Nope. (not unless you consider Stage VI heads on a low deck)

Mopar Performance could've built one, but the chances of than happening now are zero. They don't even like the 337 intake that they do have! They killed it off a few years back and Zippy got them to bring it back after I wrote a magazine article telling everyone about it. But I don't think there is anyone left at MP anymore who cares about big block engines.

They would rather sell us a $23,000.00 Hellcat engine in a crate.

No love for the heritage of the brand whatsoever...

I give MP as little of my money as possible these days.

That 337 plenum looks nice. Appears to look a tad better than the M1. Looks like the roof into the runner has a pretty decent shot to the head for as cast intake.

shows there are only 3 left in Sherwood...... $195 dealer net....

I was told if I ever use one that it will sit just over my indy valley tray plate that I use with my EZ heads ? So I was told I can leave my indy valley plate on and it will clear it and the bolts and bolt right on my eng ? Ron

Yes that might be correct. I ran the 337 intake on top of my billet valley cover. I think I had to use button head screws but that was it.

If Mopar would have cast this intake with the ports the same size just moved together with the normal center port divider width it would have been an easy match to std. port heads. You would just have to raise the top of the port and not have to widen them also.

Ron,

I have an Indy valley plate on my low deck under the 337 with the Chapman Stage VI's, I went ahead and drilled bolt head clearance under the manifold, not all the way through, just enough to clear the valley cover bolts.

I think your 493 motor is going to be right at the cusp of whether the 337 works almost as well, the same, or better ET/wise than the 440-2D. It depends really on the stall and if your car ET's relay more on torque (which I suspect), or top end power. And if it is better it may just be because your manifold is unported. Porting the lower plenum on the 2D is worth an easy 20 hp on what you already have, maybe more. It's about a 40 CFM difference, I (suprisingly) had to jet-up after I ported mine. Don't remember what you're CR is, the 517 I have is right at 11.7:1. There's no question the 337 will flow more air up top, it's just a question of which (and not all may) combinations benefit overall from it.

In order to achieve it's power potential, the intake must flow several % better than the port it feeds; On the 2D unported/ out of the box, your Upper can flow about 360 but the lower only flows about 320, so 4 of your 8 holes may be 'choked' above maybe 4800rpm on a 500" motor with the Ported EZ heads that probably flow ~360.

I installed the 337 on a RB with EZ heads and the Indy 440-6R valley cover. I just had to trim the ends on the bottom of the plate of the manifold. No biggie..... Just did it with a hand grinder.

Thanks Andy , Streetwize and Dwayne. I appreciate your input. I kinda feel the 337 is the only single plane that would fit under my hood and I just feel it would be nice to try a single plane one day just to see how the car runs compared to the dual plane Indy intake which I like alot and the single plane may not be any better on my car. Course as all of us drag racers know sometimes you will never know unless we try it and one day I may give it a shot. Might not be this year and it may not be for a few years or more but when the time is good for me I want to try the 337 if not for my own curiousity to see if the car likes it. Wize my comp is 10.6 and the head flow as I believe 329 @ .600 on the intake as Dwayne gave me my flow sheet on the heads but I have not looked at it for a bit although I am pretty sure it was the 329 @ .600. Thanks again for the advise and input from you all as I dont want to hijack this post from the OP. Ron

There are now 2 left in Sherwood..... I'd say once they're gone.... they're gone for good! I'm tempted to buy them and see if I could flip them at MaTS!

Would it really hurt anything to run this with a std port head? I always thought that since air is drawn from the cylinder, a larger port on the intake wouldn't make much difference. Can someone educate me as to why this would or wouldn't work well?

You can put a smaller port intake on a larger port head, but not the other way around. Air crashes into the wall where it is mismatched and really messes up flow. If the intake port is smaller than the head, it acts more like an anti-reversion setup. Just remember that your flow is only as high as the smallest port.

Thats true, but it's not a lot of work to get a standard 906 port window to match up to the 337, Like i said, they might have made the Goldilocks port size on purpose to broaden its possible appeal. A true MW window limits it's use.

Azzkikr, do you plan on opening up your TFs to match the 337?
I am interested in doing this. Is there a lot meat on top of the port?
Please share pics if you do, and thanks for the info so far.

After talking with Dwayne P. the current plan is to open up the Trick Flow Ports to work with this manifold. There is a lot of room to work with on the top of the port. Will probably raise it slightly more then my earlier outline. Overall size will be smaller then max wedge. I will post some pics, but I will be awhile before a get a chance to start on it.

Started on roughing in the head ports, Decided on a 2.55 x 1.35 port size.

Now I have to start working the ports in.

Looks good, I agree with definitely raising the port like in the pics.

Keep us posted on the progress. I bet you end up with one heck of a set of Trick flow high flowing heads.

If they flow 330 or so stock, Id like to see your flow numbers after you get done.

Any progress on your heads? Any flow numbers yet?

I finished opening up the intake ports and they tuned out good. I will probably send one to Dwayne to see what it flows, when I get a chance. I will post flow numbers if I do.

Any updates yet?

Agreed, I don't think so either, and thank you for the name drop, I probably wouldn't have found this thread otherwise. Glad I was able to get a couple small things done for the hobby and post about part availability while I was there, but was very low on the totem pole and limited as to what I could do/who would listen. Hope to get after it again and be a civilian, now that I've been away from it for awhile.

Nice to see you post Zippy. Have a Merry Christmas!

You too dannysbee, thank you

x2 from me.

Aw man. You too Brad, thank you sir.

Rich! Holy cow, thought maybe you jumped ship and bought a Porsche or something.

Good to see you, buddy!

Mark...thanks...still around, just a whole lot less, and not getting very much done that anyone here would want to read about...

Zippy, You have a pm

OK tried to pm, said you were over your limit.

Sorry, just deleted a few hundred. Will send you a message.

Started working on this project again. Ended up using the Superformance Max Wedge size gaskets on the heads. I did not port the floor lower, I shifted the gasket up to get the roof higher. The intake matches the floor of the port perfectly with only a small void where the gasket goes lower.

Intake ports marked to match the heads. Intake lines up good with ports in head.

I'll be getting a set of those heads to do that same thing to sometime this summer.
Going to be used with a factory x-ram.

Although, I'm looking at that pic of the MW gasket on your head and wondering if there is going to be a fitment issue with the top of the intake runner and that ridge on the intake flange of the head.

Would anyone by chance know how tall this intake is?

I'll go measure mine for you, I have the TF heads, just tell me where you would like the measurement from.

Could you measure from the intake valley plate up to the carb base? If there is a gap from the block valley to the intake valley cover could you take another measurement from the engine block valley edge to the carb base? Thank you for the help!

It was pretty tough to get a good eye but about "4.75 from block valley surface to carb base.

Awesome, thank you. I think this thing is actually slightly lower than my 6 pack intake.