Mopar Stage VI max wedge head progress and HP expectations

[Scott Kiger]

So I got these heads in a swap and decided to go all out on them. I sent them to KG Engines to have him use his CNC program on them. They turned out beautiful. Chambers ended up being 80CC after he reworked them. They will be smaller than that when finished as the heads will be milled some. They are going on a 496 that is based off a 440 block that is bored .040 with a 4.15 stroke crank. The block has billet caps, four bolt mains, a girdle, and will be filled. Overkill probably but planning on being at 15:1 compression. Running H beam rods and Icon 2618 alloy pistons at a zero deck height. Running Harland Sharp rockers with billet rocker stands. Cam is .750 lift solid roller with 292 duration. Do y’all think 750HP is a reasonable expectation out of this combo? Engine will be on alcohol.

 

[pnora]

Are these the Mopar or Chapman version. Part number will reference that. I ran them on a 440. They were a good head 20 years ago. You will need spacers or a special intake to run them. Porter racing can tell you more.

 

[Scott Kiger]

These are the Mopar version that KG went fully through for me. I have the correct 4500 flange Maxie intake for them.

 

[pnora]

These are the Mopar version that KG went fully through for me. I have the correct 4500 flange Maxie intake for them.

What intake do you have?

 

[Scott Kiger]

M1 Stage VI dominator flange. It’s the intake made for these heads. It is new never bolted on. The heads were new also before all the work was done.

 

[pnora]

M1 Stage VI dominator flange. It’s the intake made for these heads. It is new never bolted on. The heads were new also before all the work was done.

There are several intakes. My M1 with dominator flange required the spacers on a RB. There is a special intake that fits nothing else but a RB block using the stage6 heads without spacers. Thats why I asked what part number.

 

[Scott Kiger]

P4532758 is the part number. It is the right one to run on an RB block with these heads without the spacers

 

[PRHeads]

Do y’all think 750HP is a reasonable expectation out of this combo?

I’d say so.

 

[INTMD8]

They look super nice! As for the numbers, would be better to see the whole sheet.

Appears the numbers are corrected but would mean more if "corr to" wasn't chopped off.

 

[PRHeads]

To convert flow at 25” to flow at 28”, divide by .945

 

[INTMD8]

I thought the post originally said something to the effect of them being flowed at 25 so they would flow more at 28 (but the sheet appears to be corrected numbers already)

 

[PRHeads]

My take on the “corrected” part was, the “actual” test pressure(which isn’t quite 25”), being corrected to 25”.

Looking at the intake flow at .800” shows [email protected]”

331.4/.945 = [email protected]”

However......... I’m not quite sure what the writing to the right of this says.
Maybe the numbers are already corrected to 28”

 

[INTMD8]

However......... I’m not quite sure what the writing to the right of this says.
Maybe the numbers are already corrected to 28”

Yes that was my question essentially. Are they corrected to 28 or are we correcting them twice.

 

[PRHeads]

Need to see the rest of that info on the sheet.

Then....... it might be clearer.

 

[451Mopar]

Those look nice. 350 cfm sounds about right? I think they flow like the CNC B1-B/S heads if they are MW port size?
Which pistons are you using for 15:1 compression? My 4.15" stroke 400 block has the flat tops, and about 12.4:1 compression.
Also, check the piston to valve clearance. I was concerned with PV clearance on my ICON pistons with 0.726" lift and 278 @ 0.050" duration (comp HXL lobes with 1.6:1 rocker ratio.)
What springs and install height?
With my CNC MW Victor heads, I wanted to use 2.00" valve spring install height, which took 0.100" raised retainers and spring locators that are 0.030" thick (normally 0.060" thick.)

 

[RemCharger]

Those look nice. 350 cfm sounds about right? I think they flow like the CNC B1-B/S heads if they are MW port size?
Which pistons are you using for 15:1 compression? My 4.15" stroke 400 block has the flat tops, and about 12.4:1 compression.
Also, check the piston to valve clearance. I was concerned with PV clearance on my ICON pistons with 0.726" lift and 278 @ 0.050" duration (comp HXL lobes with 1.6:1 rocker ratio.)
What springs and install height?
With my CNC MW Victor heads, I wanted to use 2.00" valve spring install height, which took 0.100" raised retainers and spring locators that are 0.030" thick (normally 0.060" thick.)

Who's cnc port do you have?

 

[451Mopar]

Hughes Engines: Head Flow Charts & Comparisons

On the '71 Charger now: Edelbrock Big Block Victor (Monster (Max) Wedge Port Size) Fully C.N.C. Ported # HUG77949-S3

On the old engine: B1-B/S heads were not CNC ported, ported by Koffels Place.

 

[RemCharger]

Hughes Engines: Head Flow Charts & Comparisons

On the '71 Charger now: Edelbrock Big Block Victor (Monster (Max) Wedge Port Size) Fully C.N.C. Ported # HUG77949-S3

On the old engine: B1-B/S heads were not CNC ported, ported by Koffels Place.

Thanks, I have some of those as well going on a 440. I couldn't find a flow chart except for these with a 2.25 valve, which mine aren't.

 

[451Mopar]

I had the Hughes CNC heads inspected and flowed when I got them to verify the claimed numbers and they were very close.

I had the B1-B/S heads repaired after the old engine dropped a valve, and we installed Manely severe duty 2.25" intake valves, but haven't ported them for the larger valves.
I was looking at sending them out for CNC porting and I can't recall the place, but I think CNC ported with the bigger valve and max wedge intake port they were suppose to be around 350 cfm?

I just got a set of the CNC ported 440 Source stealth heads for a different engine. I'll have to have those checked out too.

I have my head guy flow most of the heads I have used. Most of the "out of the box" heads are down on flow from their "advertised" ratings, but the CNC ported heads usually are real close to their advertised flow ratings.
From what I have seen the "out of the box" heads will flow as advertised with some port cleanup and a valve job.

 

[RemCharger]

I had the Hughes CNC heads inspected and flowed when I got them to verify the claimed numbers and they were very close.

So are yours the big or small valve?
As I read it, hughes only published the flow with the big valve?