What heads require intake spacers when used on RB blocks?

[375instroke]

So if I was going to use an intake like the ICH DP, which only comes in RB flavor, it would fit on a 400 based stroker with these heads.

[BrianShaughnessy]

The old MP Stage VI aluminum heads need spacers for a RB.   

[ACUDANUT]

RB blocks are 413,426 wedge and 440. You have a B engine. No it will not bolt on.  Never heard of adapter either. The intake would hit the valve covers.

[elacruze]

I've been looking into this very thing myself.

Mopar Performance Stage VI heads take RB manifolds when used on B blocks and require spacers when used on RB blocks.

If you buy these heads, be *certain* you are buying the correct ones; they come in low-port (RB) and high-port (B) styles. If you get the low port heads you can't use RB manifolds on the B engine.

[375instroke]

These are the spacers I'm talking about:

[mauve66]

ad says it all,

stage VI heads on RB block need spacers

AND

stage VI heads on B block WITH B manifold need spacers

[375instroke]

Are these the only ones, though?  I think B1 heads used them, too, but that's going too far for my application.

[ACUDANUT]

 Wow, I never stop learning.  It sounds like a very expensive route though. Special heads, spacers, intake. I guess if you have the money, they will it work.

[375instroke]

It's not like all that.  Edelbrock casts the extra thickness into their raised port heads.  These heads, when used on a B engine, require the use of an RB manifold.  Now the cost is around $2,400 a pair, but that's for a set of CNC ported heads that flow 351CFM with stock port window, and 381CFM in Max Wedge size.  Exhaust is 252CFM.  You can read up about them here: Chapman/Mopar Performance Big-block Heads

[firefighter3931]

The Chapman stage VI heads are awesome, but very pricy. The amount you quoted might be for just the bare heads....better check to make sure. 

Yes, any RB manifold will work with these heads on a B (lowdeck) block. 



Ron

[375instroke]

Wow!  That price is bare, which isn't that big a deal, but it's for each head, not a pair.

[ACUDANUT]

 For that price I would just 440 all out.

[elacruze]

Does anybody know the actual ready-to-install price on a pair of Chapman heads?

Are these streetable heads? Or race-only limited cooling capacity heads?

[greenpigs]

2400 each and bare is crazy. Unless you have a extreme drag car it'd be a total waste of money if this for a street car.

[firefighter3931]

Does anybody know the actual ready-to-install price on a pair of Chapman heads?

Are these streetable heads? Or race-only limited cooling capacity heads?

Based on the $2400 per head (bare) you'd probably be looking at $5500 for a complete ready to run set excluding rocker arms. A little rich for my blood ! 

There are a lot of better flowing heads available....for less money. 

I'm sure these would run fine in a street application and make excellent power. 



Ron

[elacruze]

There are a lot of better flowing heads available....for less money. 

Ron

Then what's all the hype about raised ports, offset rockers, yada yada and so much $$ if they don't pass the most gas?

I have a 'stock' set of Edelbrock RPMs on my 505" which will probably stay just the way it is for a touring motor. I'm not sure I want to do my 400 build with a B manifold. I know that's a little cryptic but...and I may just broom the 400 out to do a Turbo /6 instead. The turbo motor would be a more interesting learning curve.



Eric

[firefighter3931]

The Chapman standard port heads are at the top of the food chain, no doubt....but you pay bigtime for that CNC porting + R&D ! 

On a street driven 500in motor the standard port heads aren't a bad option....lots of low end grunt and no need to wind it to the moon to make descent power. Those motors are all done by 6k due to the port section cross area which limits power but that isn't necessarily a bad thing depending on the usage. 

Slant 6 turbo sounds like a neat project 



Ron

[375instroke]

This is the power they made with the MW port windows:
Our 470 cranked to the tune of 774 hp at 6,700 rpm, and 667 lb-ft of torque at 5,900 rpm.

The small port heads flow more below .600" lift with a smaller volume, so I'm sure they would do much better on a street motor, but my God, the cost.  I guess the same can be said for a Hemi motor.

MP/Chapman Head Flow (Advertised)
   Stage VI 260   Stage VI 285 MW   
Lift     In    Ex    In    Ex
.100"    71    55    77    55
.200"   157   112   151   112
.300"   230   177   220   177
.400"   290   211   283   211
.500"   325   233   330   233
.600"   351   242   364   242
.700"   351   252   375   252
.750"         260   381   260

[375instroke]

Just found a guy selling a set of "professionally ported," 2.19 intake Stage IV heads with 2 new M1 manifolds, offset Crane rollers, pushrods, and spacers for $1500.  Sounds like a good deal, but I don't know if I could use that much head.  Would 330CFM, as the ad says, too much for a street motor with 3.23 gears?