I use to run a destrokes 383.. was a HIGH rpm
engine.. I shifted it a 9800 rpm(4 speed car)
in a 2900# with me Valiant ... it was more of
a square block for the aerodynamics... I used
a set of home ported max wedge heads on it with
a tunnel ram

I'm thinking that you should get some B1 heads and turn the RPMs up. I don't think you will need the torque as you probably will be spinning in the salt from what I was told from a friend that ran a NASCAR Ford 358 in a B/SR tying to top 200 MPH. Maybe use a 5-speed transmission or maybe a 6-speed with OD to get top end? Sounds like a fun project.

If you need a super low profile billet dry sump pan I have one. I built it for a project but do not need it anymore. It should help you get the engine as low as it will go in roadster.

Wonderful head work there fast68!

Guess they is later smog castings?

I'm going for 2.225 intakes and 1.84 exhausts myself...

Those are a set of 346’s.
2.14/1.81

I did work on a set of the repro 518-M’s last year though.

I’ve never had a set of original 518’s in my shop, so I can’t say how similar they are to the -M versions.
But I can tell you this........ both the intake and exhaust ports on the 518-M’s are shaped nothing like the early 286 heads.

I race a fairly fast Max Wedge Superstock car, the first lite weight Plymouth shipped in 64 (in SS/EA I have ran 9.39 at 141), I developed my own engine program as their have not been any SS Max Wedges go this fast. I cross the Stripe at Sea Level at around 8700rpm, I did everything on the heads myself and I have done both original 518 and 518M heads, you have to know which ones to pick. The exhaust side does not need much work but to make 800hp the intake Port needs lots of creative work. Good luck with your Project and be selective on who you use.

Max Weg

And they say big blocks won’t turn! I bet it sounds sweet up top, I had one back in the 70s, a whole nuther sound.

Many thanx for the quick replies Guys!

The port work and pictures are truly AWESOME!

Very interesting your comment on 518 to 286 Max Wedge ports?
I am fortunate to have a set of 62 286 heads and the ports are awesome lol.

There were a lot of trick iron headed 440's here in the 80's and 90's.
But the evolution of Aluminum has pretty much 'killed them off'...

For me I want to run in a kinda 'Superstock' set-up with a six-barrel on my 71 GTX.
Its a Canadian car with 346 heads and the engine is BLUE?

The car was raced in the 90's and has succumbed to rust issues.

After a 20 year resto I want to get her back out, with another 440 or 511.
Sold all my Ali heads but have a few 'old school irons' laying around lol.

Gonna practice on some ex Jensen sixpack 902's for now with a 3/8 inch manifold spacer.

ps, my old 452ci iron-engine used to rev to 7200, would have gone more but I didn't want to wreck an ex 69 SP Superbee block, (now back in the car)!

Just watched Nick on YT running the 520cube 71 GTX engine.

It has answered a lot of questions real quick for me!

Don't use a stock intake or stock exhausts lol...

But the real question is?

How good or bad 'are' the Stealth heads...

Can I 'out-port' them with iron???

We did buy a set back in 2005 and fitted them on a 543 engine with high compression.
It was pretty new stuff back then and I think it ran high tens in a street car (65 Coronet).

I would be happy with 11's with my homeported 902's and 511 cubes.
Start with an Edelbrock Torker and then hopefully an iron six-barrel...

It might be a post from 4 years ago, but I wasn't around for it, so I'm gonna say......

That's a really cool car, Mike. Love it. Thanks for the pic.

4 years is a 'blink' in Mopar time!

I still feel like its the mid 80's (to me), so little time/money and so much to do...

It was always our 'mantra', got to be an all iron engine and normally aspirated!

But I'm still looking for an Aluminum MP hemi head, please Zippy lol...

Back to iron 440 heads!

Best size of valves is my next question?

I have 2.225 intakes and 1.84 exhausts...

Am I over-valved???

We always spent a week on Intake porting and a day on exhausts...

Now we know better...

Best iron head exhausts I have ever seen...

The Stealths can be ported to flow better than a ported iron head with much less work , I have the Super Stealths that I ported to Max Wedge on my 512 street car, they quit making them they use .650 offset intake rockers, My junk runs pretty good for what it is, small cam, 9.7 compression, if you want the stock looking head with straight spark plugs they can be made to flow pretty good for a NON raised port head.

Actually, there isn’t all that much done to those ports. Just some basic clean up and smoothing.
The 518-M exhaust ports are pretty good as cast ...... especially the later versions.

On the 906 and 346, etc…., what was the reason for the big intrusion sticking out on one side of the exhaust port? I see those 518 heads do not have that at all.

The area filled in on one side of the ex port in the OE heads is to facilitate more coolant capacity in the head.
There is a corresponding mild bulge in the adjacent intake port.

Apparently that’s less of a concern to the aftermarket head designers. They’re going for the flow instead.

A straight valve size comparo doesn't cover what's happening. The ports function at violently different pressures: .74 psi WOT vacuum in the intake manifold, perhaps 7 psi vacuum in the cylinder near TDC, vs. 70 psi pressure in the cylinder when the exhaust valve cracks open.
Opening the exhaust even a few degrees earlier helps a weak port.

I know I’ll get beat up for this but we always found good power with stock size intake valve and the max wedge exhaust (1.88) just mild bowl work under the seat. Never could understand why it was said they wouldn’t help. Maybe what poly said, 70 psi

Yes it does!! It has a very flat power curve from 6800 to 8700 and could spin higher but there is no need. The biggest thing is crankshaft stability so a 2 bolt block does not like it, therefore a crossbolted conversion is required. The 518M heads latest version Exhaust Ports can be made to flow almost to good. With creative work on the intake ports you can make a stock port size with a 2.08" intake valve flow over 330cfm. And support North of 800hp na.

Max Weg

Ok I will be the Big Dummy in the conversation. So is the 518M head a Max Wedge head?