STEALTH Head Update.... A "lowly" 440 Street Engine

[Challenger340]

OK,
Dyno'd the 2nd lowly 440 yesterday.
Virtually Identical Shortblock

However,
* This one uses the CompCams XE284H Hydraulic Flat Tappet Cam, .507"/.510"Lift, easy on parts.
* The better fully Street Ported Stealth Heads
* A port-matched Performer RPM Intake Manifold.

545 HP @ 5500 rpm
562 Ft/Lbs of Torque @ 3500 rpm

Lots of vacuum for power brakes.
Had to fix a sticky Oil Pump relief valve later on(gained hp later to just under 560 @ 5700), but I'll leave that later Dyno sheet, until I get photos up on the Headwork done on this one.

Not too Bad for a Flat Tappet Hydraulic Cam at .510" lift ?

[BSB67]

   Thanks for posting the results

[heyoldguy]

Not too bad? I'd say that is very, very good. I hope we can approach those numbers when we go the the EZ heads and 10.4:1 compression.

[Challenger340]

Not too bad? I'd say that is very, very good. I hope we can approach those numbers when we go the the EZ heads and 10.4:1 compression.

LOL !
Something tells me.... I don't think YOU will have much problem "approaching" those numbers with the INDY EZ Heads ? and 10.4 ? more like leaving these numbers far behind like a faint spec in the rearview ?

Gotta LUV them INDY EZ Heads !!

[Cooter]

So what's the 411 on Steaths now?
good?
Need reworking still?
Out the box?
Castings porous still?

[GPULLER]

Thanks for posting!  The more of these 440 builds I read the less I think about a stroker.  560+ ftlbs of torque would be plenty scarey enough in my 4100lb '66.  Very impressive!

[Challenger340]

So what's the 411 on Steaths now?
good?
Need reworking still?
Out the box?
Castings porous still?

IMO,
The Stealth Heads biggest claim to fame, is indeed their factory "Stock" external appearance once painted, for those looking wishing to hide the aluminum/aftermarket Head.
OOTB,
both sets we received had negative longside Bowl transitions to the seat, the worst 2 individual Heads we then reworked with Porting and better Seat prep, with a 1.98" seat I.D. to correct(284 cam Engine)
the 2nd pair then.... only treated too seat prep on the stock I.D. leaving the "dip" in the longside wall above the seat, and then just a bowl and Intake opening clean(274 Cam Engine).

* No excessive casting porosity was found.
* OOTB Machining & Assembly, Guide Clearance, Seat Prep, etc., was otherwise satisfactory for Street Engine use.
* OOTB Flows approached 260 cfm @ .550"
In our opinion only
The Stealths should only be considered for OOTB configuration useage in sub-500hp applications
and for 500 Plus HP applications
substantial reworking should be undertaken a competent Shop, and Budgeted for in the initial purchase.

No wars wanted, just our opinion.

Nice Head for the money.... just don't anybody go kidding themselves, that they are going to install basically OOTB Stealths on a Stroker, add a Cam and make great Power ? FORGET IT... wasting your time.

[firefighter3931]

So what's the 411 on Steaths now?
good?
Need reworking still?
Out the box?
Castings porous still?

IMO,
The Stealth Heads biggest claim to fame, is indeed their factory "Stock" external appearance once painted, for those looking wishing to hide the aluminum/aftermarket Head.
OOTB,
both sets we received had negative longside Bowl transitions to the seat, the worst 2 individual Heads we then reworked with Porting and better Seat prep, with a 1.98" seat I.D. to correct(284 cam Engine)
the 2nd pair then.... only treated too seat prep on the stock I.D. leaving the "dip" in the longside wall above the seat, and then just a bowl and Intake opening clean(274 Cam Engine).

* No excessive casting porosity was found.
* OOTB Machining & Assembly, Guide Clearance, Seat Prep, etc., was otherwise satisfactory for Street Engine use.
* OOTB Flows approached 260 cfm @ .550"
In our opinion only
The Stealths should only be considered for OOTB configuration useage in sub-500hp applications
and for 500 Plus HP applications
substantial reworking should be undertaken a competent Shop, and Budgeted for in the initial purchase.

No wars wanted, just our opinion.

Nice Head for the money.... just don't anybody go kidding themselves, that they are going to install basically OOTB Stealths on a Stroker, add a Cam and make great Power ? FORGET IT... wasting your time.

The Stealths OTTB are a 500hp head on a pump gas street build....no matter what the displacement is. It's stricly a matter of cylinder head flow and the Stealths are a bit weak out of the box as compared to an Edelbrock or Indy EZ.

A few years back MFR426 (Mike) built a mild hyd cam 500in motor with non-ported stealth heads. It made 510hp/590tq. A set of unported RPM's would have upped the power another 40-50Hp and made more torque as well. 
 
Mike's build with dyno results at Ray Barton's shop :

http://www.dodgecharger.com/forum/index.php/topic,43911.0.html

When you compare the power numbers it becomes obvious why Pro's like Bob can make a big difference in power output with a little handywork on the die grinder.   


Ron


Ps. Bob, those are very nice numbers on the second budget 440 as well. Peak tq @3500 is gonna be lots of fun on the street. A nice 10in converter and he'll be flyin 

[Cooter]

Thank you gentlemen for the info. Very good to know. Was thinking bout a set of Stealths and like myself, a good ole straight up answer is what I got.

[Challenger340]

I should add here, and subsequent to my last post, that I would agree with Ron(Firefighter3931),
that we too believe....
the Edelbrock RPM Head "OOTB" is a superior, and has more power potential in OOTB form than the Stealths, based upon our Flow Data on both.

We are only one Flowbench... but I am thinking the Eddy's are 20-40hp better based upon the application "OOTB".

[Cooter]

Don't have no high dollar flow bench, but I'm thinking once CNC ported, the Stealth 'could' support??
Maybe 600-700hp?(stroker)

[heyoldguy]

A cnc ported Stealth shouldn't have any problem with 640-660 HP on a 4.15 stroke pump gas engine. A very good set of Stealths can go 750 HP on a pump gas 451.

[Troy]

Just a quick question because it seems relevant to the discussion...

How much would a guy lose with iron heads with the same work done to them on the same build? Closed or open chamber. It might help guys who are on the fence about going with aluminum.

Troy

[Challenger340]

Just a quick question because it seems relevant to the discussion...

How much would a guy lose with iron heads with the same work done to them on the same build? Closed or open chamber. It might help guys who are on the fence about going with aluminum.

Troy

That is a really good question Troy, and I think I have the answer in another Dyno Sheet ? but I will have to go find it and get it up here.
We did a "resto" style 440-6 pack just awhile back, that might be a good comparison as it used the same 274 CompCam, but similar Head Cleanup Prep etc. on the 906 Castings, albeit stock 2.08"/1.74" Valves.
We tested through the Iron HP Manifolds and 2 1/4" pipes though ? ..... seems to me if I recall correctly 445HP and 515 Trq ?
Stay Tuned... I'll find it.

[Troy]

Just a quick question because it seems relevant to the discussion...

How much would a guy lose with iron heads with the same work done to them on the same build? Closed or open chamber. It might help guys who are on the fence about going with aluminum.

Troy

That is a really good question Troy, and I think I have the answer in another Dyno Sheet ? but I will have to go find it and get it up here.
We did a "resto" style 440-6 pack just awhile back, that might be a good comparison as it used the same 274 CompCam, but similar Head Cleanup Prep etc. on the 906 Castings, albeit stock 2.08"/1.74" Valves.
We tested through the Iron HP Manifolds and 2 1/4" pipes though ? ..... seems to me if I recall correctly 445HP and 515 Trq ?
Stay Tuned... I'll find it.

Cool! I forgot to look to see if a "stock" type build had been previously posted. I know guys will say that it costs the same to bolt on a set of untouched Edelbrocks (probably Stealth too) as it does a set of ported iron heads and you end up with more power. Just looking for more of a same-same comparison (ported vs ported). I'm more than happy with 500 HP on the street - especially if it looks stock with power brakes and runs on pump gas (without having to constantly mess with it).

Troy

[justcruisin]

Very good reading and great info, you say the 284 cam had enough vacuum for brakes, what did it pull? I am considering swapping out my 275 for a 284 cam along with some steeper gears and gear vendors. I seem to recall that you are not a fan of the HL/XE series, can you tell us why?

[Challenger340]

Very good reading and great info, you say the 284 cam had enough vacuum for brakes, what did it pull? I am considering swapping out my 275 for a 284 cam along with some steeper gears and gear vendors. I seem to recall that you are not a fan of the HL/XE series, can you tell us why?

I think the XE284 pulled around 13"@ 900 rpm, which I think is fine for power brakes given an Engine like this will have an 11" or Tight 10" Convertor behind it ?

Nah, the HL Cams we tried didn't work for us... BUT, that doesn't mean they are no good ?....we were using them as swap Cams in Engines with unknown Head Flow... so no data or real reason to dismiss them ? and certainly not fair for me to diss them in any way... probably fine Cams in the right application.

As for the Comp XE Cams, we've used them lots, proven results, they work well for us when we know what we want to achieve, so we keep using them.
No point in us re-inventing the wheel with Hydraulic Flat Tappet Cams... because... we just don't do enough Flat Tappet Hydraulic Cam Engines to worry about it ? We have a "known"... easy on parts / lifters / and bleed down on the Johnsons with 120# seats and sub 300# nose.
NOT saying there aren't "better" F.T. Hydraulics out there... there PROBABLY IS.... just we have no time to find out.

just a suggestion here....
maybe pm Firefighter3931(Ron) on this Site ? He is far more current with Hydraulic Cams than I am ? and he has lots of valuable knowledge/feedback particularily on the Lunati stuff in different combos ?
He can probably tell you exactly what to expect with a Lunati Cam versus a given CompCam.
just saying... that's who I WOULD BE ASKING ?

[Challenger340]

Just a quick question because it seems relevant to the discussion...

How much would a guy lose with iron heads with the same work done to them on the same build? Closed or open chamber. It might help guys who are on the fence about going with aluminum.

Troy

That is a really good question Troy, and I think I have the answer in another Dyno Sheet ? but I will have to go find it and get it up here.
We did a "resto" style 440-6 pack just awhile back, that might be a good comparison as it used the same 274 CompCam, but similar Head Cleanup Prep etc. on the 906 Castings, albeit stock 2.08"/1.74" Valves.
We tested through the Iron HP Manifolds and 2 1/4" pipes though ? ..... seems to me if I recall correctly 445HP and 515 Trq ?
Stay Tuned... I'll find it.

Cool! I forgot to look to see if a "stock" type build had been previously posted. I know guys will say that it costs the same to bolt on a set of untouched Edelbrocks (probably Stealth too) as it does a set of ported iron heads and you end up with more power. Just looking for more of a same-same comparison (ported vs ported). I'm more than happy with 500 HP on the street - especially if it looks stock with power brakes and runs on pump gas (without having to constantly mess with it).

Troy

I'll have to get in the 'puter and dig for that 6-pack sheet Troy.... stay tuned as we're really busy right now.
personally,
I DO think the Stealths OOTB with minimal work, and a bigger Cam like the XE284 instead of the XE 274, would probably get the 500 HP, WITH the ability to paint them and play "stock" sleeper.
And really,
that XE 274 Engine, probably would have got to 500HP(others have) if not for the piss-poor longside wall in THOSE Castings as delivered ootb.
We did NOT fix the XE274 Engines Heads with Porting, like we did on the XE284 Engine, and I know it hurt it  badly on the Dyno with the smaller Cam.

[69wannabe]

So if I was going to buy a set of aluminum heads and bolt them on and go I would benefit from the edelbrock RPM's rather than buy a set of stealth heads and then have to have work done on them and I would have to find someone who would know what they were doing too. Not alot of mopar fans where I live but if it were a chevy it would be different!! Wouldn't I have to swap in the recommended valve springs for a XE284 comp cam on the RPM heads? The 600 lift springs seem like they would be too much for my 510 lift cam. What would your thoughts be on a set of iron open chamber heads with the 214/181 valves and minor porting done compared to the stealth or RPM heads?? I would hate to spend $1500 and not notice any difference in the performance of the engine. Love these numbers on these stock stroked 440's!!! I have a spare 78 block in case anything ever happened to my 493 and it would go back with a stock stroke like one of these engines! I like my 493 but my stock stroked 440 was plenty powerful!! I got a wild hair and ordered the stroker kit and spent a pile of cash when I already had a great running engine. Live and learn I guess!!

[Budnicks]

So what's the 411 on Steaths now?
good?
Need reworking still?
Out the box?
Castings porous still?

IMO,
The Stealth Heads biggest claim to fame, is indeed their factory "Stock" external appearance once painted, for those looking wishing to hide the aluminum/aftermarket Head.
OOTB,
both sets we received had negative longside Bowl transitions to the seat, the worst 2 individual Heads we then reworked with Porting and better Seat prep, with a 1.98" seat I.D. to correct(284 cam Engine)
the 2nd pair then.... only treated too seat prep on the stock I.D. leaving the "dip" in the longside wall above the seat, and then just a bowl and Intake opening clean(274 Cam Engine).

* No excessive casting porosity was found.
* OOTB Machining & Assembly, Guide Clearance, Seat Prep, etc., was otherwise satisfactory for Street Engine use.
* OOTB Flows approached 260 cfm @ .550"
In our opinion only
The Stealths should only be considered for OOTB configuration useage in sub-500hp applications
and for 500 Plus HP applications
substantial reworking should be undertaken a competent Shop, and Budgeted for in the initial purchase.

No wars wanted, just our opinion.

Nice Head for the money.... just don't anybody go kidding themselves, that they are going to install basically OOTB Stealths on a Stroker, add a Cam and make great Power ? FORGET IT... wasting your time.

The Stealths OTTB are a 500hp head on a pump gas street build....no matter what the displacement is. It's stricly a matter of cylinder head flow and the Stealths are a bit weak out of the box as compared to an Edelbrock or Indy EZ.

A few years back MFR426 (Mike) built a mild hyd cam 500in motor with non-ported stealth heads. It made 510hp/590tq. A set of unported RPM's would have upped the power another 40-50Hp and made more torque as well. 
 
Mike's build with dyno results at Ray Barton's shop :

http://www.dodgecharger.com/forum/index.php/topic,43911.0.html

When you compare the power numbers it becomes obvious why Pro's like Bob can make a big difference in power output with a little handywork on the die grinder.   


Ron


Ps. Bob, those are very nice numbers on the second budget 440 as well. Peak tq @3500 is gonna be lots of fun on the street. A nice 10in converter and he'll be flyin 

very well said

[Budnicks]

I should add here, and subsequent to my last post, that I would agree with Ron(Firefighter3931),
that we too believe....
the Edelbrock RPM Head "OOTB" is a superior, and has more power potential in OOTB form than the Stealths, based upon our Flow Data on both.

We are only one Flowbench... but I am thinking the Eddy's are 20-40hp better based upon the application "OOTB".

thank you for an honest assessment...

[Steve P.]

WOW!!  Great info in this thread. Thank you Bob, for bringing us all in on your builds. I'm loving the numbers. One day I would love to put together a nicely refined, Planned and built), motor and get back in the seat. Until then I get to dream about builds like this..

I am wondering how you would go. Cheaper heads that you can fix or more expensive heads that you won't have to spend crazy hours on fixing? I'm asking on a similar build. Say - 550 HP/TQ on a weekend driver and now and then race weekend?

[Challenger340]

WOW!!  Great info in this thread. Thank you Bob, for bringing us all in on your builds. I'm loving the numbers. One day I would love to put together a nicely refined, Planned and built), motor and get back in the seat. Until then I get to dream about builds like this..

I am wondering how you would go. Cheaper heads that you can fix or more expensive heads that you won't have to spend crazy hours on fixing? I'm asking on a similar build. Say - 550 HP/TQ on a weekend driver and now and then race weekend?

Steve
Thanks for the kind words.... really though, I am just an old retired fart playing in his Shop ? so take my opinions, as just that... and old fart playing around.

I haven't seen many Heads period.... that don't require dis-assembly, and at least some work/improvement from as delivered ?
Even the expensive ones that Flow more, still need work sometimes OOTB ?
Some are better than others, but no matter INDY, Eddy, Brodix, Stealth, all should be checked, and most if not all, can usually stand some improvement even it is just a guide re-hone.

We hadn't seen much of the Stealths prior to these ? only a few times in passing so this was a good opportunity.
That said,
and again here, just our opinion only, if a guy is going to apply the normal Dis-assembly/Check, and then contemplate the "least" amount of Port work/Cleanup conduscive to a 550/550 type pump gas build.....
for the cheapest total initial outlay & work
Then the Edelbrock RPM Head would be my first choice

The Eddy's may cost more initially than the Stealth.... but require less re-work for the 550/550 levels IMO.

[Steve P.]

 

Old fart or not, you have provided a ton of great info and your experience is fantastic. I know I love reading your posts!!! 

[Budnicks]

Old fart or not, you have provided a ton of great info and your experience is fantastic. I know I love reading your posts!!! 

X2 on that