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I’m not sure how well you had the bolt holes for the spacer and manifold lined up in this pic........ but if they were lined up pretty well....... then it looks like the transition from the spacer to the plenum could use a little attention.

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Edit- I see that spacer is more of a sheer plate than a spacer......... so it may not be quite as critical(or..... it may not matter at all).
 
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I believe a “1250” carb has a bigger throttle bore than a 1050 or 1150.
2.125” vs 2.00” I believe.

If the sheer plate is for the bigger bore...... it’s likely just bigger than the manifold(which is probably sized for a 2.00” throttle bore).
 
dave story ported my chapman's mw stage 6 mopar heads , he claimed over 300 cfm on the intake ports . i build them for a 470 , but now building a 4.5 stroke rb 540 plus cubs . should i be looking into another pair of heads for this build ? as so using the new mopar mw intake with two 750 or bigger carbs or hillborn injection . a roller cam of custom grind . not trying to steal this tread just looking for info , so anyone can advise me on this new combo .
 
Yes u need bigger heads for a 540. The 6s will be the choke point even if they are max wedge ported. I have Indy SRs and they still are not big enough to support 540 cubes. I know a guy that used ported stock port Victors. He says it dynoe’d over 800 hp. He has a 69 Charger that ran 9.69 last weekend. Kim
 
Imo...... at least from what I’ve seen through my own efforts, SR’s are definitely a superior head compared to a non-Chapman Stage 6 Head.

Getting “big” numbers from an SR head does take a fair amount of work though.
 
my stage 6 mw heads were not cnc ported , so chapman is wrong , but i had dave story of story porting in crestwood , ky . he did the porting though my cam grinder/builder . dave claimed well over 300cfm in the intakes side . my question is , are these stage 6's mw ports pro ported enough to feed my 540plus street engine and turn 6500 plus ? or should i rethink the heads ? and why are trick flows not in this discussion ?
 
Because it’s about the heads I have for my build. I have Stage 6s and Indy SRs standard port. I got a Super Victor and 1250 Dominator. Now I need to decide which set gets max wedge ported for the SV. Kim
 
The TF heads aren’t in this particular discussion because....... oldkimmer doesn’t own any of them.

Depending on the rest of the combo, with your original style stage 6’s on a 540” motor...... I would expect it to make peak power somewhere in the 6000rpm range.
If it had enough compression, cam, header, intake, and carb to get it there.
So, yes...... the top end of the “usable” power curve would be in the 6500 range.

Of course, there is really only one way to know where any given combo of parts will actually make peak power.

On a bigger cube combo like what’s being talked about here........ I would expect a properly ported set of SR’s would make as much power as the TF270’s.
I think the same could be said for the 285cc MW Chapman stage 6’s.
In fact, they’re probably the best of the three.
 
I know a guy that used ported stock port Victors. He says it dynoe’d over 800 hp. He has a 69 Charger that ran 9.69 last weekend. Kim

Just goes to show...... there’s more than one way to get it done.
 
I have sold 1 set of my Procomp Victor knock offs and traded the other 2 sets for other parts to use now and in the future. I got the 1250 and SV on trade. I just needed the fuel log and air cleaner which I have found now. So MW ports are in the near future for sure. Kim
 
My build consists or a 440 block that has been bored .060. Billet main caps with studs and line bored. Parallel decked, notched for 4.5 stroker crank. Probe balanced rotating assambly. 7.100 I beam rods. Reverse dome Pistons with tool steel wrist pins. Romac balancer. Compression will be 11-1 with 75 cc heads and .040 gasket. I have a solid roller or a solid flat tappet. 1.6 rockers. Lift will be approx .620 with the roller or .730 with the sft. With 1.6s. Kim
 
prh , thanks for your insight in my build , and sorry for squeaking my way in the thread , but when you guys talk heads i'm all ears . my cam guy thinks the tf 270 should be used on my 540plus . he thinks there a better head than the stage 6 mw's . but as you say there the better of the three being talked about here that kim has . do to my short rpm and street/strip use .
 
prh , thanks for your insight in my build , and sorry for squeaking my way in the thread , but when you guys talk heads i'm all ears . my cam guy thinks the tf 270 should be used on my 540plus . he thinks there a better head than the stage 6 mw's . but as you say there the better of the three being talked about here that kim has . do to my short rpm and street/strip use .
What cam u gonna run? Kim
 
my cam guy thinks the tf 270 should be used on my 540plus . he thinks there a better head than the stage 6 mw's . but as you say there the better of the three being talked about here

You’re not paying attention.
I said the 285cc Chapman stage 6 was probably the best of them.
That head really has almost nothing in common with an original stage 6.

If your heads aren’t cnc ported, they are not “Chapman” stage 6’s.
The castings being machined and ported by Chapman........ is what makes a stage 6 head a “Chapman” stage 6 head.

If you posted a couple pics of them, it should be pretty easy to clear up exactly what you have.
 
i'm using a mopar 440 rb "r5" block motor home and ind , thick webs and cylinders . its going over .06 do to a few scared cylinders , it got plenty of wall to handle the next up in bore , hoping it cleans up at 4.40 , but if needed it can go larger as long as we can find rings , pistons can be made . and i'm using i beam 7.1 rods , bryant 4.5 stroke crank turn under to 2.2 bbc pin . i've got a set of7075....alum main caps and a stud griddle , arp fasteners through out .
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kim , my cam grinder has something in mind , he hasn't give me the specs yet . but i'm thinking t&d rockers assemblies . stage 6 mw's need an off set rocker package . i'm building this engine to last with good old usa made stuff , i want the americans to enjoy having a job , and of course parts that last over and over again .
 
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