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440 Source Stealth Heads

Houle #382

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Just wondering who's running the 440 Source stealth heads, any issues with them ? What kind of power gain with the stock exhaust manifolds.
 
Just wondering who's running the 440 Source stealth heads, any issues with them ? What kind of power gain with the stock exhaust manifolds.
Just my opinion, but running those heads with stock manifolds is a waste of good horsepower, not to mention money.
 
Just wondering who's running the 440 Source stealth heads, any issues with them ? What kind of power gain with the stock exhaust manifolds.

You need to tell us what you have now and how it performs to give an idea of relative improvement.
 
Lots of people running, them, and the issues are pretty well documented by now.

Type these in your google search bar, tons of good reading--

Stealth head site:www.forbbodiesonly.com

Stealth head site:board.moparts.org
 
Those links didn't take me to.....very much.....
They aren't really links... type exactly as I showed, or just copy and paste one into the googly search. You'll get pages and pages of relevant results.
 
They aren't really links... type exactly as I showed, or just copy and paste one into the googly search. You'll get pages and pages of relevant results.
Got it.....but that was different lol
 
Got them on my 496. But I copied the "Mopar for the Masses" build just larger engine. Had the ported at Muscle Motors so I don't know how they would've performed. They say the heads flow pretty close to advertise. That said, I've got 610hp at the crank. As said above, no point if using stock exhaust.
 
I Disagree with the ‘pointless if you use stock manifolds’ comments. Depending on your build you can still gain quite a bit. Just not as much as a car using a header or more free flowing exhaust.
 
I Disagree with the ‘pointless if you use stock manifolds’ comments. Depending on your build you can still gain quite a bit. Just not as much as a car using a header or more free flowing exhaust.
Waste of money!! You can get those same gains with stock heads if you're going to use restrictive stock manifolds.
 
Out of the box running stock cam, exhaust manifolds they should be a good improvement. Many will say to have them checked out which is a good idea, at least to make sure the valve job is correct and no sticking in the guides. If you have higher lift cam, the springs should be swapped out, retainers and locks changed, etc.

Check out the Edelbrock heads for a little more.
 
On a stockish motor, the power improvement will be about the same, with or without headers. And it could be a little, or it could be a lot.

This is why we need to know what the OP is starting with. If on a stockish motor, the improvement will be somewhat of a function of how bad the current heads are, which could be a lot, or not. Generally, there is a compression boost that comes along with the Stealths that helps. A little professional prep on the Stealths will help as well.

Assuming a stockish motor, the OP's improvement could be 10 hp, or 50 hp, depending on what he's starting with
 
You need to tell us what you have now and how it performs to give an idea of relative improvement.

My current set up is, 440 .03 over Straightline performance hydraulic flat tappet cam 226/238 duration @.05 503 lift with adjustable hydraulic rockers, Edelbrock Performer RPM intake with a Edelbrock 650 AVS-2 carb. Pertronix 3 distributor. 4 speed with 3:54's. This winter I plan on going with a Scott Brown Hydraulic Roller setup and possibly a new set of heads not sure who's heads right now. Not sure about the Eddie's as the plugs are set at a angle and if I decide to go with headers not all headers will clear the plugs. 440 source heads and Mopar Performance heads have straight in plugs like factory heads, I like the Mopar heads but are about $800 bucks more than the 440 source heads. I do know some guys running the Mopar Heads and they really like the improvement but I do have a budget and the way this country is heading who knows what's going to happen and might need my car fund for other things to survive LOL
 
My current set up is, 440 .03 over Straightline performance hydraulic flat tappet cam 226/238 duration @.05 503 lift with adjustable hydraulic rockers, Edelbrock Performer RPM intake with a Edelbrock 650 AVS-2 carb. Pertronix 3 distributor. 4 speed with 3:54's. This winter I plan on going with a Scott Brown Hydraulic Roller setup and possibly a new set of heads not sure who's heads right now. Not sure about the Eddie's as the plugs are set at a angle and if I decide to go with headers not all headers will clear the plugs. 440 source heads and Mopar Performance heads have straight in plugs like factory heads, I like the Mopar heads but are about $800 bucks more than the 440 source heads. I do know some guys running the Mopar Heads and they really like the improvement but I do have a budget and the way this country is heading who knows what's going to happen and might need my car fund for other things to survive LOL

A few comments if you stay with manifolds:
I assume the Scott Brown cam you have now is ground with a 112° lsa, as that is what Scott normally does. In my opinion, your 226/238 on a 112 lsa is a real nice exhaust manifold cam.

Be sure to have a direct and detailed conversation with Scott on the hyrdaulic roller upgrade. A 238°/246° even on a 112° lsa might be a little big, but I've never tried a hydraulic that size on a 440. And seat timing matters too. An aquaintance had his exhaust manifold car running 11.50s @ 116 with a smaller Scott Brown solid lifter cam, then switched to a 240° -ish hydraulic and is sucked power out of it, like 3 tenths and 3 mph. I think it hurt average power (verses peak power), but that is a guess.

In short, exhaust manifold motors are sensitive to cam timing and unforgiving with the wrong cam.
 
I have a set on my 383. with manifolds. I wanted them mostly for the crap gas factor so I would not have any knock or ping. my only issue is the valve cover rail is cast wrong in the corners and it only has a little bit of the gasket coverage it should have. of course it is on the lower rear corner where it leaks, so it takes a bit of finessing to keep it sealed. Otherwise not built for max performance. If i was after more power I would up the compression and cam and use headers. but I like them. Also my engine Never runs hot no matter what the temperature , it can idle for ever in traffic. Also the weight savings is HUGE, with an aluminum intake , heads, water pump and housing, the engine weighs the same as a small block. like free horse power
 
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A few comments if you stay with manifolds:
I assume the Scott Brown cam you have now is ground with a 112° lsa, as that is what Scott normally does. In my opinion, your 226/238 on a 112 lsa is a real nice exhaust manifold cam.

Be sure to have a direct and detailed conversation with Scott on the hyrdaulic roller upgrade. A 238°/246° even on a 112° lsa might be a little big, but I've never tried a hydraulic that size on a 440. And seat timing matters too. An aquaintance had his exhaust manifold car running 11.50s @ 116 with a smaller Scott Brown solid lifter cam, then switched to a 240° -ish hydraulic and is sucked power out of it, like 3 tenths and 3 mph. I think it hurt average power (verses peak power), but that is a guess.

In short, exhaust manifold motors are sensitive to cam timing and unforgiving with the wrong cam.

Yes my current cam has 112 lsa, I have a nephew who has a 70 Cuda 440 four speed and he's running a hydraulic roller Comp cams Extreme Energy 23-712-9 it's 236/242 @.05 and 541 lift and he has the crappy heads on it so he has to run 93 octane and it runs very good. I bought my current setup from Scott so I'm pretty confident with him.
 
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