Mopar Stage VI 6 heads questions

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monc440

monc440

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Ok I’m in the planning phase for my big block combo and I have been doing research on the stage 6 heads I’m going to use. I have read many articles on these heads and have seen many different builds being done. I have seen guys posts about the engines they are running these heads on including the cam size and what not and it seems the more I read the more questions I have.

Questions I have at this point.
1. How much value lift will these heads take out of the box?
2. Do I need offset rocker arms?
3. Do I need custom length push rods?

Here is more info if you need it.

So the heads I have are 4532134 casting from the mid 90’s. They are not the early design that had porosity issues and are not the Chapman heads. They are just as they were out of the box, never been milled or had any port work done.

The Mopar description of these heads say they can be used with all stock big block parts, valves, rockers, push rods, use a RB intake on a B engine and use spacer plates on an RB engine. That all sounds good.

I tried to find a spec or installation sheet from Mopar but no luck and I can’t find my Mopar engine book. So I start doing some research to find out how much value lift the heads can take and I start finding all kinds of different info. Some info says max lift is .600, other says .630, another says .675 and one post I found the guy says he is running a .700+ lift. The problem is the posts that I find don’t say what work if any was needed to get that kind of lift. I did find some info on not to have the valve pocket cut for taller springs because it will weaken it and a stiff spring can cause it to fail.

As I’m doing this research I find posts saying you need offset rockers and custom push rods to use these heads but the Mopar description says they work with stock parts.

Thanks in advance for any info.
 
okay what port size are your heads , my p4532657's are max wedge port sized , had them ported by story porting , yes mine use offset rockers . there are a few guys here running these stage 6's . i was lucky enough to score a rb max wedge port m1 stage 6 dominator carb mouth intake of this site .

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The amount of valve lift it can take is related to the valve length used combined with the spring height, retainer and the valve seal height. I’m sorry that wasn’t specific but the parts used on the head can vary a lot.

I don’t know about rocker offset.

I’d say yes to custom length pushrods as a better than a 90% probability. Considering your not using a stock can and the rocker may not be the same or in the same exact place as the stock rockers.

The head was designed within the confines of the stock architecture, hence there limitations.
 
rumblefish360 said:
The amount of valve lift it can take is related to the valve length used combined with the spring height, retainer and the valve seal height. I’m sorry that wasn’t specific but the parts used on the head can vary a lot.

I don’t know about rocker offset.

I’d say yes to custom length pushrods as a better than a 90% probability. Considering your not using a stock can and the rocker may not be the same or in the same exact place as the stock rockers.

The head was designed within the confines of the stock architecture, hence there limitations.
Click to expand...
Ok I understand that I could use a longer length valve, if I do that do I need to use a spacer under the rockers?

Thanks
 
As I remember, I ran that # head on my 440 Duster in the 90's.
Stock offset Crane Rockers Back then. I always make my own pushrods
so I do not know if the production ones would fit. A 590 Clay Smith Solid
Roller cam was biggest that I ran with High Compression TRW pistons due to
piston and Valve Clearance. It ran 10.46 @ 126 back then with 830 Holley.

As I recall = On the flow bench it stalled at 600 lift.
 
Post 3. Valve lift (IMO) should be as much as the valve will tolerate without a bunch of issues. Or, until the lobe gets so aggressive you have to reduce lift.

Ive only done one set of those heads and that’s one of the few aluminum heads I won’t do again. They take a crapload of work. But the engine that I did those for heads was .2 better than his B1 stuff. Then I got to do his B1 stuff and it was my first engine (and his) that did 1k hp NA on a single 4.
 
Take the heads to a machine shop. They should be able to tell you when spring bind is and what max lift can be. I'm not sure about rocker offset. I believe stock port may be ok but you can probably throw the head on a block and drop some stock rockers on and see if they line up. I'm pretty sure the exhaust will be ok but the intakes may require an offset. I have MW Stg 6 heads. I needed offset intake rockers. A custom set of pushrods are a small price to pay for proper length and function. And you didn't say but obviously different style lifters will need different length pushrods.
And I think you are leaving a lot on the table by running them as is. At least have a shop disassemble and do a minor clean up. It's worth it.
 
66Valiant528 said:
Take the heads to a machine shop. They should be able to tell you when spring bind is and what max lift can be. I'm not sure about rocker offset. I believe stock port may be ok but you can probably throw the head on a block and drop some stock rockers on and see if they line up. I'm pretty sure the exhaust will be ok but the intakes may require an offset. I have MW Stg 6 heads. I needed offset intake rockers. A custom set of pushrods are a small price to pay for proper length and function. And you didn't say but obviously different style lifters will need different length pushrods.
And I think you are leaving a lot on the table by running them as is. At least have a shop disassemble and do a minor clean up. It's worth it.
Click to expand...


100% true. That head out of the box leaves a lot to be desired.
 
@PRH Maybe Dwayne will chime in.I'm sure he has seen a set or two and could touch them up if needed.
 
monc440 said:
Ok I understand that I could use a longer length valve, if I do that do I need to use a spacer under the rockers?

Thanks
Click to expand...
I hate to sound like a dick & I don’t want to come off as one, but here but here we go…..

Your 1st question was very general, general answers given.
Your second question was a little more focused but it’s still in a wide open field. So I explained it.

Your third question is more focused but still in a big field.
I’ll answer it in a second. First! What are you planning on doing with the heads?
Will your application need standard length valves or longer valves? What length do they need to be or will be?

Moving the rockers upwards is easy. Moving them front to back, (towards the valley or towards the exhaust side) or whatever is harder. This maybe needed depending on your valve lift, spring height and ultimate goal. We have no idea of what that is.
I do realize you’re looking for information and I’m happy to answer what I know. Which isn’t a heck of a lot on these heads.

Keep asking questions!

The suggestion to take to a head guy/machinist is an excellent one. What you could do is get to stock valves and used springs and a valve seal, etc…. Set up 1 valve and check it with a mic. This you could do at home if you have a mic and such tools.

Do you have experience worked by on cylinder heads at all, as in setting them up?
 
rumblefish360 said:
I hate to sound like a dick & I don’t want to come off as one, but here but here we go…..

Your 1st question was very general, general answers given.
Your second question was a little more focused but it’s still in a wide open field. So I explained it.

Your third question is more focused but still in a big field.
I’ll answer it in a second. First! What are you planning on doing with the heads?
Will your application need standard length valves or longer valves? What length do they need to be or will be?

Moving the rockers upwards is easy. Moving them front to back, (towards the valley or towards the exhaust side) or whatever is harder. This maybe needed depending on your valve lift, spring height and ultimate goal. We have no idea of what that is.
I do realize you’re looking for information and I’m happy to answer what I know. Which isn’t a heck of a lot on these heads.

Keep asking questions!

The suggestion to take to a head guy/machinist is an excellent one. What you could do is get to stock valves and used springs and a valve seal, etc…. Set up 1 valve and check it with a mic. This you could do at home if you have a mic and such tools.

Do you have experience worked by on cylinder heads at all, as in setting them up?
Click to expand...
lol. I don’t think you are being a dick at all. As far as head work experience I have done steel heads in the past. I have my own equipment to do valve seats and valves. I have done port jobs on 906 heads using Mopar templates. I have not done anything in 15 years and just getting back into engine building. Everything I have ever done was for my own stuff and I try to use what I have because I have never had the money to do a big budget build. I do however have a big selection of Mopar big block parts that have been accumulated over 50 years by my family. These heads are my first aluminum heads.

Ok to get more specific question I was asking is if I use stock length valves, retainers, keepers and rockers what lift can these heads take? What I was thinking was at some time when the heads were marketed as using all stock parts that they would have listed the maximum valve lift with stock parts. I guess I was thinking along the lines of when I was working on 906 or 452 heads when I wanted a cam bigger than.550 I would have the valve guides cut down and maybe the spring pocket cut down.

After seeing a couple replies on here I’m thinking that the offset rockers would be for the max wedge port design that was offered in this head. Mine are standard port design but I didn’t want to assume that stock style rockers would work.
 
monc440 said:
lol. I don’t think you are being a dick at all. As far as head work experience I have done steel heads in the past. I have my own equipment to do valve seats and valves. I have done port jobs on 906 heads using Mopar templates. I have not done anything in 15 years and just getting back into engine building. Everything I have ever done was for my own stuff and I try to use what I have because I have never had the money to do a big budget build. I do however have a big selection of Mopar big block parts that have been accumulated over 50 years by my family. These heads are my first aluminum heads.

Ok to get more specific question I was asking is if I use stock length valves, retainers, keepers and rockers what lift can these heads take? What I was thinking was at some time when the heads were marketed as using all stock parts that they would have listed the maximum valve lift with stock parts. I guess I was thinking along the lines of when I was working on 906 or 452 heads when I wanted a cam bigger than.550 I would have the valve guides cut down and maybe the spring pocket cut down.

After seeing a couple replies on here I’m thinking that the offset rockers would be for the max wedge port design that was offered in this head. Mine are standard port design but I didn’t want to assume that stock style rockers would work.
Click to expand...


What lift you can use is determined by (the number one factor IMO) how much load can the fasteners and the shafts take? Five 5/16 bolt won’t take the load of five 7/16 bolts. Even the hood downs matter. Using OE style hold downs won’t take the load of a block system like the W series heads use.

And, in a similar manner, the W style rocker system will not take the load of a Jesel or T&D system. It just cant.

The other factor is length of valve and what your retainer to guide clearance is. You can machine the guide down and get more clearance.

The answer is if you can’t figure that stuff out, find someone who can. It’s not hard.

You can also change the length of the valves, but unless you or whoever is doing doesn’t understand correct valve train geometry you will make your world a very miserable place using longer valves.
 
monc440 said:
lol. I don’t think you are being a dick at all. As far as head work experience I have done steel heads in the past. I have my own equipment to do valve seats and valves. I have done port jobs on 906 heads using Mopar templates. I have not done anything in 15 years and just getting back into engine building. Everything I have ever done was for my own stuff and I try to use what I have because I have never had the money to do a big budget build. I do however have a big selection of Mopar big block parts that have been accumulated over 50 years by my family. These heads are my first aluminum heads.

Ok to get more specific question I was asking is if I use stock length valves, retainers, keepers and rockers what lift can these heads take? What I was thinking was at some time when the heads were marketed as using all stock parts that they would have listed the maximum valve lift with stock parts. I guess I was thinking along the lines of when I was working on 906 or 452 heads when I wanted a cam bigger than.550 I would have the valve guides cut down and maybe the spring pocket cut down.

After seeing a couple replies on here I’m thinking that the offset rockers would be for the max wedge port design that was offered in this head. Mine are standard port design but I didn’t want to assume that stock style rockers would work.
Click to expand...
Are your heads bare? Are you asking if factory cast iron head valves can be used in these heads? Just trying to clarify.

As for rocker arms, if I am not mistaken, the Stage VI heads had their own rocker arm offset. The ports may be standard size, but the casting is thick so an offset rocker arm is required to clear the casting. The same thing happened with the Stage V cast iron head. They said you could run standard rocker arms, but many of the castings did not have the pushrod area machined enough for clearance. I was running the Stage VI offset rocker arms on Stage V cast iron heads to allow the pushrod to clear the head without grinding any more off the head.
I will try to find my 2002 Mopar Performance catalog.
 
AAAAAAAAA HA!

Now who has a B/RB manual handy?
The offset amount is probably within.
 
monc440 said:
lol. I don’t think you are being a dick at all. As far as head work experience I have done steel heads in the past. I have my own equipment to do valve seats and valves. I have done port jobs on 906 heads using Mopar templates. I have not done anything in 15 years and just getting back into engine building. Everything I have ever done was for my own stuff and I try to use what I have because I have never had the money to do a big budget build. I do however have a big selection of Mopar big block parts that have been accumulated over 50 years by my family. These heads are my first aluminum heads.

Ok to get more specific question I was asking is if I use stock length valves, retainers, keepers and rockers what lift can these heads take? What I was thinking was at some time when the heads were marketed as using all stock parts that they would have listed the maximum valve lift with stock parts. I guess I was thinking along the lines of when I was working on 906 or 452 heads when I wanted a cam bigger than.550 I would have the valve guides cut down and maybe the spring pocket cut down.

After seeing a couple replies on here I’m thinking that the offset rockers would be for the max wedge port design that was offered in this head. Mine are standard port design but I didn’t want to assume that stock style rockers would work.
Click to expand...

Thanks! I appreciate that, I didn’t wanna come off in a rude manner. Sing that you have done head work in the past though it’s been a while, glad to read your getting back into it.
 
Bobzilla said:
Are your heads bare? Are you asking if factory cast iron head valves can be used in these heads? Just trying to clarify.
Click to expand...
I know I can use factory size valves in the head. I’m asking at what point valve lift do I need to start modifying parts?

I have a set of 906 heads with stainless steel valves that I will use in the stage 6 heads if I can with the cam lift I want.
 
I apricate all the comments. I didn't want to make my first post a novel with all my background and my may of doing things I just wanted to see if someone on here could answer some questions about these heads before I start buy/trading for parts. I know I can mock up a valve and measure the clearance but I live in Michigan, my shop isn't heated and it's cold outside. Call me lazy or maybe I'm just getting old. Also my wife hates it when I start brining engine parts in the house in the middle of winter. lol

So a little about me and my way of thinking. I grew up on a farm where I learned to fix all kinds of things at a young age. Why did I learn these things, because when something broke my dad or grandpa would have to fix it and I wanted to learn how to do it. They couldn't just stop and say well I guess the cows don't eat today because the tractor will not start and you couldn't call the local tractor shop to come fix it for you because A, it would be 3 days before they could get there and B, because we couldn't afford it. My dad and mom were also car people from drag racing in the 60's - 70's to building hot rods, street rods and muscle cars up until my dads passing in 2022. My first engine rebuild was a briggs on my mini bike, I rebuilt my first V8 when I was 12, a 1955 Dodge 270 Hemi, my dad walked me thru it. By the time I was 21 I had completed my associates degree in Auto Tech and was a state certified technician. I have always tried to do everything I can on my own and over the years I have built everything on old cars from top to bottom.

I have always had to build on a budget unless I was building something on customer pay. I have never had the bank for a pro built anything. I have a family and farm that comes first and toys come probably 5 or 6 on the priority list so basically not much left over. I learned at a young age that some guys have their cars built and other guys build their own. I have always fell into the latter group, not by choice but by necessity. I would love to be able to go online and order 10K in parts, take everything to a shop to have a 1000HP engine built for the Duster but that isn't going to happen. So I have to use what I have if I can or sell/trade things I have to fund my project. So when people say just take the heads to a professional and have them build well I would if I could and I will if I find it is out of my ability to do it but then that will take money from something else.

So that's where I'm coming from, first try to use things I already have, second trade things I have to get things I need and three as a last resort buy new parts.

As far as these heads go I know I can't use stock stamped steel rockers and push rods with high pressure springs without either bending a push rod or pushing the push rod thru the stock rocker but I need to know if I need stock geometry rockers or offset rockers. Thanks to Bobzilla for the info on this, now I know what to look for.

If anyone knows what the max lift is on these heads using stock length valves and retainers that would be great. Or if someone has info like I ran a xx size cam but I had to use do xyz to do it that would also be helpful. If I can't get info on here I will in time measure for myself and report back.
 
My suggestion is, the first thing you should do is check the valve drop for all 16 valves before going any farther.
It’s not uncommon for them to vary .030……or more.
If they’re within .060, then getting them within about .015 or so for all the intakes, and the .015 between all the exhaust would be the goal.
I’ve also seen where on each head the drop is close between the intakes, and between the exhaust, but the two heads aren’t very close to each other.
If that’s the case, then you have to determine what needs to be addressed to get them closer to each other(milling, sinking valves, or some of both).
Get a game plan for how you’re going to address this……if it’s a problem on your two heads.

One other thing you’ll want to check……..
Put a dowel pin on each end and rest a straight edge against them. Then measure from the straight edge to the intake surface at the two ends.
You’d like them to be within .010”.

I will say this, back when these were popular, I worked on quite a few……….and every set had their own little surprise.

As for lift, make life easy for yourself and plan on running less than .700”.
 
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These are the last ones I worked on:

Some stage 6 stuff


A follow up to that thread…….
Speaking with the owner of those heads, it appears I misunderstood how they ended up being the way they were.
I had assumed he was involved with the rework that had been done previously, but that was not the case.
He had just ordered a number out of the MP catalog……and that’s how they showed up.
I can tell you one thing, when he got them, they had already amassed a bunch of shipping labels on the boxes from all the places they had already been.
Where any of that previous work was done is a big mystery.
 
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Companion thread:

Mopar stage 6 heads

Hey there guys !!! I'm looking at a set of Mopar stage 6 heads to buy part # p4532796They are brand new in the box ....just had a couple questions about them ...Cc for for comp ?Flow?Bolt on a normal intake without spacers ?Angle or straight plug ?I heard that there were casting with crack...
board.moparts.org board.moparts.org
 
PRH said:
My suggestion is, the first thing you should do is check the valve drop for all 16 valves before going any farther.
It’s not uncommon for them to vary .030……or more.
If they’re within .060, then getting them within about .015 or so for all the intakes, and the .015 between the exhaust.
I’ve also seen where on each head the drop is close between the intakes, and between the exhaust, but the two heads aren’t very close to each other.
If that’s the case, then you have to determine what needs to be addressed to get them closer to each other(milling, sinking valves, or some of both).
Get a game plan for how you’re going to address this……if it’s a problem on your two heads.

One other thing you’ll want to check……..
Put a dowel pin on each end and rest a straight edge against them. Then measure from the straight edge to the intake surface at the two ends.
You’d like them to be within .010”.

I will say this, back when these were popular, I worked on quite a few……….and every set had their own little surprise.

As for lift, make life easy for yourself and plan on running less than .700”.
Click to expand...
Great info. Thanks
 
monc440 said:
As far as these heads go I know I can't use stock stamped steel rockers and push rods with high pressure springs without either bending a push rod or pushing the push rod thru the stock rocker but I need to know if I need stock geometry rockers or offset rockers. Thanks to Bobzilla for the info on this, now I know what to look for.
Click to expand...
Just to make sure it was clear, I am not saying your heads cannot use factory offset rocker arms, I am only saying you will need to mock them up and check if stock offset will work. If they have plenty of pushrod clearance with stock offset there would be no need to use a greater offset.

monc440 said:
I know I can use factory size valves in the head. I’m asking at what point valve lift do I need to start modifying parts?

I have a set of 906 heads with stainless steel valves that I will use in the stage 6 heads if I can with the cam lift I want.
Click to expand...
What valve diameter is in your cast iron heads, for the valves you are hoping to use? The factory cast iron head intake valve is a 2.08" head diameter, the exhaust is usually 1.74" diameter, and I think all of the stage VI heads came with the seats cut for 2.14" intake and 1.81" exhaust. That is why ask about the valves you have, since that is what you are hoping to use. Nothing at all wrong with trying to use parts you have, if they will work.

The Mopar catalog listed the available valve lengths as 4.86" for intake and 4.87" for exhaust. I do not know if that was accurate, but that is what it showed.
 
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