Stealth, RPM, 906 heads

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IQ52

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So after playing on the flowbench for two weeks of testing, we have some results for the Standard Stealth, RPM and 906 iron head with the standard stock intake port windows.

At .700" lift the Stealth went 337 cfm, the RPM 335 cfm and the 906 went 338 cfm. When we opened up the intake port windows, the Stealth went to 346 cfm and the Edelbrock RPM went to 350 cfm. The 906 heads in this session were not tested with the raised port window.

Funny thought. You could buy valves, springs and porting, a pair of $999.90 Stealth heads, and have heads that flowed as good as bare, CNC ported B1 BS heads for way less money. Stealth heads, not the "Super Stealth". I have no idea what "SS" heads may do. HAH, maybe nothing!
 
the real purpose for the 906 heads is if you are doing a perfect resto for 68,69,70 B or RB

chrysler put them on all the big blocks those three years. it would be worth it to have them CNC ported if you had a 69 R/T or Dart GTS or something

the RPM's and Stealth are great for medium builds. i think the torkers are for all out race. the indy's are very nice heads too. just gotta be careful which ones you get because of the maxwedge size ports and stuff you might end up having to buy new headers intakes etc.

port flows are nice on most of them
here's a page with listings of most available heads
http://users.erols.com/srweiss/tablehdc.htm#Chrysler_Big_Block
http://users.erols.com/srweiss/tablehdc.htm#Chrysler
 
Salty Dog said:
Any info on the MP Stage VI heads? (Non CNC, but ported and unported versions?)
Click to expand...

We are really buried in work at this moment or I would pull one off the shelf and test it. I have unported stock flows at the shop. May be I can post those later today. If I remember, they are about equal to or less than the out of the box Stealth.
 
OH! HEY! No problem, make money first! I like dead pres's myself. I think there my best friend. No complaints, zipped mouths, leave when I tell'em to....etc....

I'd like to know for surely how they are when ported if you have that info. OOTB info would be cool, but, ported is the big question in my head. NO ONE seems to know much of anything about these heads. Also, by chance, would you know the port sizes in cc's? And at what amount of inches there flowed at?

Thanks IQ!
 
IQ52 said:
So after playing on the flowbench for two weeks of testing, we have some results for the Standard Stealth, RPM and 906 iron head with the standard stock intake port windows.

At .700" lift the Stealth went 337 cfm, the RPM 335 cfm and the 906 went 338 cfm. When we opened up the intake port windows, the Stealth went to 346 cfm and the Edelbrock RPM went to 350 cfm. The 906 heads in this session were not tested with the raised port window.

Funny thought. You could buy valves, springs and porting, a pair of $999.90 Stealth heads, and have heads that flowed as good as bare, CNC ported B1 BS heads for way less money. Stealth heads, not the "Super Stealth". I have no idea what "SS" heads may do. HAH, maybe nothing!
Click to expand...
Thats good info but what about flow at lower lifts, any numbers for that? Also I noticed you said stock port windows but I'm assuming there was work done on the ports with numbers like that. How good is the casting quality on the Stealths?
 
IQ52 said:
Funny thought. You could buy valves, springs and porting, a pair of $999.90 Stealth heads, and have heads that flowed as good as bare, CNC ported B1 BS heads for way less money.
Click to expand...
So what would a guy be looking at for this level of porting, if a guy would send you a set of bare heads?
 
Salty Dog said:
LOL, no John, I do not have a set, yet is also the key word. Cost is a factor, but not the limiting one at all. Where is he located?
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he is located in Burlington ,Vt. , not sure if he is on this site but he goes by fast68plymouth. Porter Racing Heads . 802 851 1955
 
Not picking on anything but I also dont care what a head flows at .700 since im never going to run that much cam in a street engine. Im more interested in the .5-.650 numbers.
 
JohnRR said:
he is located in Burlington ,Vt. , not sure if he is on this site but he goes by fast68plymouth. Porter Racing Heads . 802 851 1955
Click to expand...


I have spoken with Mr. Porter on numerous occasions, and he sure seems to be a stand up fellow. Years ago I saw him talk a guy out of buying a set of his heads, as he told the fellow he had a better set on his car already. That impressed me, as a lot of guys would have just made the sale.
 
JohnRR said:
he is located in Burlington ,Vt. , not sure if he is on this site but he goes by fast68plymouth. Porter Racing Heads . 802 851 1955
Click to expand...
OMG! Yea, I do know the screen name very well. Thanks John, your of great help. Thank you!

BBBCUDA said:
I have spoken with Mr. Porter on numerous occasions, and he sure seems to be a stand up fellow. Years ago I saw him talk a guy out of buying a set of his heads, as he told the fellow he had a better set on his car already. That impressed me, as a lot of guys would have just made the sale.
Click to expand...

Now this is something that is just simply great to read.
 
72BBSwinger said:
Not picking on anything but I also dont care what a head flows at .700 since im never going to run that much cam in a street engine. Im more interested in the .5-.650 numbers.
Click to expand...

You should be more concerned with the low lift numbers , the valve only see max lift once per cycle , it's sees all the other lifts TWICE , valve opening and valve closing .
 
John - Dwayne doesn't come here. While I'm sure I understand why, we suffer as a result...lol

"You should be more concerned with the low lift numbers , the valve only see max lift once per cycle , it's sees all the other lifts TWICE , valve opening and valve closing ."

I agree 1000%
 
Salty Dog said:
Any info on the MP Stage VI heads? (Non CNC, but ported and unported versions?)
Click to expand...

Got this Stage VI head maybe 10 years ago. I think they now have slightly different castings with smaller guide bosses and machined intake bowls. Least wise I got one like that in a box here.

Out of the box........................Some porting today, stock port opening

.100.....66 cfm...............................88 cfm
.200....131...................................161
.300....188...................................218
.400....212...................................265
.500....226...................................302
.600....229...................................324
.700....232...................................331

This old head was a lot worse out of the box than I thought it was.

72BBSwinger said:
Not picking on anything but I also dont care what a head flows at .700 since im never going to run that much cam in a street engine. Im more interested in the .5-.650 numbers.
Click to expand...

Come on guys, I was just playing and going for maximum lift numbers and you want me to fess up to lower lift numbers?

OK here they are.

440 Source ported head, raised port opening, recommended 4.375 bore.

.100"..........72.6 cfm
.200".........152.2
.300".........218.3
.400".........266.8
.500".........307.7
.550".........325.4
.600".........336.8
.700".........346.3

Sorry I didn't check it at any intermediate lifts other than .550". This was just an experimental port one day recently.

I forgot to bring the sheet with the stardard port opening. Maybe I can post it way later tonight.


MRL Performance said:
So what would a guy be looking at for this level of porting, if a guy would send you a set of bare heads?
Click to expand...

'Bout 2 Grand

72BBSwinger said:
Is this Mr. LaRoy?
Click to expand...

Yeah
 
I didn't want to blow your cover. You seemed to be having fun flying incognito.. :)
 
Thanks IQ, awesome dude, thanks!

The numbers look like they would support a fairly healthy engine up to 400. Kind of reminds me of about what a average porting on a W2 could do...ya know, without really pushing the W2. IDK about a 440 though. Humm, i guess it would depend on whats going on.
 
Salty Dog said:
Thanks IQ, awesome dude, thanks!

The numbers look like they would support a fairly healthy engine up to 400. Kind of reminds me of about what a average porting on a W2 could do...ya know, without really pushing the W2. IDK about a 440 though. Humm, i guess it would depend on whats going on.
Click to expand...

Day was kinda shot so I went ahead and played some more. Went through some useless antics and lost some flow on the Stage VI and then hit this.

.100"........75 cfm
.200".......151
.300".......215
.400".......264
.450".......288
.500".......308
.550".......331
.600".......335
.650".......339
.700".......344
.750".......348

Its enough to make 775 HP with a 451.
 
MRL Performance said:
Yes, would love to see the flow as it ramps up to the .700" mark.
Click to expand...


440 Source Stealth head flows, with the stock intake manifold opening, in various states of "tune".


.100".......88...........83..........77
.200"......158.........158.........153
.300"......214.........220.........216
.400"......261.........264.........265
.500"......290.........297.........306
.600"......306.........313.........324
.700"......318.........329.........337
 
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