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

[Ghoste]

This is an awesome thread btw. 

[Challenger340]

Would there be any other changes if the 284 Cam was used??

No, we don't do anything different between the 274 Cammed Engines and the 284 versions.
But the power jumps with the 284 Cam..... far more than one would expect when swapping a Flat Tappet Cam for another Flat Tappet Cam.
because,
the smaller 274 cam in function.... really acts more like a "cork" than anything else, with the Cylinder Head Porting/Prep we do already there, which should be considered as a "mid-way" step between the ootb Stealth Head, and the CNC ported Stealth Version.

You can look back in this thread for the 284 Cammed version numbers... but about 540hp and 550Ft/Lbs.... improvement well worth an afternoon Cam Swap if so desired.
albeit.... you are starting to move into more Convertor required, Lumpier Idle Quality, more Gearing, etc.

So everybody might say.... "why not just use the 284 Cam and brag the higher HP number" ?
well.....
DRIVE-ABILITY is the best answer.... for a drop-in Engine capable of really waking up a musclecar with the least amount of changes required ?
The 274 deal is small enough for 3.55 gears, good idle, and a 24-2800 stall convertor is lots !
with the added benefit....
of knowing with any later afternoon Cam swap.... more power is already "built in".  

[firefighter3931]

Good stuff Bob....500hp/tq at just under 5500rpm is a fantastic street build. 

Anything more will be a waste with a street tire anyway.....been there, done that 



Ron

[Challenger340]

   I meant by you!  Everything posted here by you is gospel in my book. I went to great pains and waited 9 months just to have Chuck at CJ's Automotive handle my mild build. 
  I'm certain your builds are much stronger and will last longer as your really going the full route with the new heads/connecting rods, extra attention to tolerances and so on. I wouldn't hesitate to have you build my next engine even with hefty shipping to Florida! I was just wondering what YOUR out the door total was around? 
 

$20,000 friggin Dollars !    .... just kidding

Thanks for the kind words B5, much appreciated.
that said,
I am not here soliciting any work, as I am pretty much retired now, just an old fart playing in his shop still doing a few Engines for Drag Racer friends, and really.... doing so(Soliciting work) or pricing on here, would not be within the "genre" of this Site, which IMO, has gotten it RIGHT ! .... devoid of the usual Car Guy Site B.S. that seems to permeate the Internet.
Wouldn't ya know it... takes a Mopar Site where guys can honestly trade ideas.... to show the rest how it SHOULD be done !

My point being...
I think the "lowly 440" combo's... are reasonably "repeatable" for many on their own locally... on a Budget... with just some attention to detail ?
So IMO, a good "Fit" here ?

IMO, you most certainly do NOT need me !
just some good basics:
* Some good Headwork done on the Stealth's.... available at a Performance Shop in your area ~$600. ?... or consider the CNC "super" Stealth, albeit pushes the Budget ?
* Some decent "generic" Machining.... doesn't have to be "Blueprinting", just so long as they have a Torque-Plate and can Machine decently straight & round ?

It is NOT a case of....  "Even Blind Chickens get the odd kernel of Corn", ...... IMO, ANYBODY should be able to repeat fairly close !

Personally,
I just like the idea of a std 440 inch Engines "useable" rpm range for street useage, with the entry level Heads... versus Price Point ?
especially since,
with respect to minimal other modifications required in the Car ? to things like Cooling & Fuel Systems that are Taxed vrs increased Stroker Cooling, etc.

The Idea was:
* to build around "entry level" Cylinder Heads, which even ported IMO,.... don't "fit" the Strokers real well for useable rpm range without a large Camshaft, so the std 440 was chosen.
* Cost Effective, but expandable between 475 to 550 hp, so No Roller Cam expenses, High Spring pressures, etc., etc., yada, yada, just a $129. Hydraulic Flat Tappet Cam and NO MAINTENANCE.
* Minimal vehicle support system upgrades required, Cooling, Fuel, Exhaust, Gearing, etc.... again here, the lowly std 440 seemed to fit better ? IMO.

[Steve P.]

I think this is one of the best threads ever!!   

Can't think you enough Bob.... 

[justcruisin]

How would you rate your prepped stealths compared with OOTB edelbrock RPM's on this kind of build - performance wise.

[Paul G]

Given this combo;
4100# car
3:91 gears
2400 stahl converter
Eddy heads with the basic prep package from Dwayne Porter, instead of stealths.

Which combo would be recomended? The XE274 combo or the XE284 combo since everything else in these builds is the same?

[Challenger340]

How would you rate your prepped stealths compared with OOTB edelbrock RPM's on this kind of build - performance wise.

OUR prepped Stealth Heads are far better than an OOTB Eddy Performer rpm... 20+ cfm across the curve below .500" Lift even WITH the smaller Valves.
That said,
Easier to get there with the Eddy's as a starting point.

[Challenger340]

Given this combo;
4100# car
3:91 gears
2400 stahl converter
Eddy heads with the basic prep package from Dwayne Porter, instead of stealths.

Which combo would be recomended? The XE274 combo or the XE284 combo since everything else in these builds is the same?

I dunno Paul  
I don't know what Dwayne's "basic prep package" on the Eddy's Flows ? ... so I can't comment, and he would have his own Rec for HIS Heads anyways.

Just say'in...
We invested some time and effort, to get a fatter .200" to .500" Cam Lift Stealth Head prep & flow package... that we were happy with, and could be accomplished in one day, That would draw the MAX from the relatively smooth Idling .488" 274 profile, and still work with the .507" Lift 284.
In other words...
we worked the Heads targeting THOSE Cams.... no point chasing .550" or .600" lift Flows, for Cams that don't go there ?
We developed really FAT off the seat Flow.... figured out the quickest way to do it.... easiest to Port afterward.... went with it.
Once you go ahead a fawk a Port up to see what it does NOT like....
pretty easy then....
to go the "udder way" to figure out what it DOES LIKE
and along the way....
figure out what you need to do for BIG Lift Cams as well.

[Bob T]

Bob, Thanks for publishing your results and tips for all to read & learn from, quite a handy reference for budget engine spends for those of us that are not super clued up on different combo's and what could work best for the chosen application, much appreciated.
It'll most surely be helpful when I get around to my upgrade.


Have a cold one on me  

[Paul G]

Thanks for this entire thread Bob. It has really explained a lot of things, like how not to spend too much money on a build that is not really needed to achieve great results for a street car. To reach 500+ HP and mid 500 TQ with a stock stroke is fantastic. No need for a big inch build. (which I think was the entire point of this thread)

One last question, Is the 60 overbore required to achieve the expected results?

[Challenger340]

Thanks for this entire thread Bob. It has really explained a lot of things, like how not to spend too much money on a build that is not really needed to achieve great results for a street car. To reach 500+ HP and mid 500 TQ with a stock stroke is fantastic. No need for a big inch build. (which I think was the entire point of this thread)

One last question, Is the 60 overbore required to achieve the expected results?

Thanks for the kind words, we'll keep on having FUN with the small Cam 440's for a while yet around here, so stay tuned for some more results.

No, on these last two- 440's..... the one Dyno'd is .040" and the other will be .030"... Bore size is making diddly difference on these.

As time permits....
we're going to machine up a couple for inventory, and have them ready to go. It would be nice to just have them in "stock", that we can then just "Cam" and final assemble according to our data between 475 to 550hp as req'd, then Dyno before leaving.
I am ready for some better small Cam design testing very soon.
They seem to fill a "niche" for decent power without breaking the Bank, at least around here anyways, so why not.

[b5blue]

I'd be real interested in seeing how the old school MP# P4452783 "RESTO" cam did. (268/284-46*overlap-.450/.458lift on 115*center line.) It's the same as the six-pack spec. except for the six-pack's lower lobe slope. (MP# P4529270) 

[Brass]

Or the Crower 282HDP Ron likes.  If you're taking requests. 

But truly, thank you for sharing.   

[Paul G]

The challenge I am facing is explaining to the local machinist how I want the engine to be built. They all have there own ways and preferred builds.

If I am getting this right, the heads are the key to it all.  The machinists I have spoke to so far really haven't convinced me they are very good at head porting.  So that is what leads me to Porter Racing. Dwayne has a great reputation, and he ships anywhere.

[500Jon]

Hi Challyman
I'm another Old Fart engine builder here in Limey-land...

We have a V8 here in the UK called the all-aluminium Rover 3.5 litre.(based on the 50's Buick iron block engine). Very popular in the 70's and 80's...
Anyways, a specialist company here in the South-East of England used to build them up to 500hp...
Back ten years ago I joined them and we built Mopar engines too.
Sadly due to outside pressures it has now gone outta business, but we had some fun along the way.

My opinion is and always will be, don't use 40 year old connecting-rods!!!
The bulk of Mother Mopar 440 rods either 'LY' or 'SP heavy' are terrible to say the least!!!
There are plenty of good aftermarket rods with fully floating bushes pre-installed.
Forging quality is ten times better and no need to lighten and balance...

Apart from that, ALL is good in the World with your amazing builds!!!

ps., as I always say, anyone can build and engine..its the quality of machining THAT'S IMPORTANT!!!

[DC69RT]

Bob,
      The 274 Cammed 440 did you guys dyno the engine with the HP Exhaust manifolds? Seeing as this engine spec would more than likely be fitted in a "Stealth" engine bay was wondering the torque /hp loss (Torque more important as if we are serious the engine on the street spends most of its time from idle to 3000 RPM, torque is what we like on the street).
I am just about to start a build same engine as the 274H 440 but as 512 stroker with HP exhaust manifolds, 2.5" exhaust with Hemi mufflers, 3.23 gears 727 standard convertor, a true street engine. More concerned with torque numbers below 3000 RPM. Only question will the 274 be too small in a 512 ci and would the 284 idle and act like the 274 in a 512.
Wondering if you have ever built a 512 with the same lowely street spec?

[BSB67]

Well, I would suggest........, oh wait, I'm not Bob.

[Challenger340]

Bob,
      The 274 Cammed 440 did you guys dyno the engine with the HP Exhaust manifolds? Seeing as this engine spec would more than likely be fitted in a "Stealth" engine bay was wondering the torque /hp loss (Torque more important as if we are serious the engine on the street spends most of its time from idle to 3000 RPM, torque is what we like on the street).
I am just about to start a build same engine as the 274H 440 but as 512 stroker with HP exhaust manifolds, 2.5" exhaust with Hemi mufflers, 3.23 gears 727 standard convertor, a true street engine. More concerned with torque numbers below 3000 RPM. Only question will the 274 be too small in a 512 ci and would the 284 idle and act like the 274 in a 512.
Wondering if you have ever built a 512 with the same lowely street spec?

Nope, that was with 2 1/8" Dyno Headers I believe ? which probably KILLED Torque as too big for that Engine,
and
Nope, never done a 512 with a Cam that small or with Stealth Heads.

BSB67 has LOTS of experience with Big Engine/Little Cam combo's... so I'll digress and let him talk !

[DC69RT]

BSB67,
          Please suggest!!!

[BSB67]

Here is what I suggest.  Start a new thread with what you have (engine, parts, car, drivetrain), what your goals are, AND what you budget is.  Then we can go from there.

Or maybe better yet, reach out to Dwayne Porter.  He is a professional in the high performance service business, a Comp Cam distributor, and has speced a bunch of exhaust manifold cams for both street guys and racers.

On here he goes by: PRH

porterheads@gmavt.net

This is going on at Moparts, some info.  http://board.moparts.org/ubbthreads/ubbthreads.php/topics/2439243/1.html

[Challenger340]

Bob,
      The 274 Cammed 440 did you guys dyno the engine with the HP Exhaust manifolds? Seeing as this engine spec would more than likely be fitted in a "Stealth" engine bay was wondering the torque /hp loss (Torque more important as if we are serious the engine on the street spends most of its time from idle to 3000 RPM, torque is what we like on the street).
I am just about to start a build same engine as the 274H 440 but as 512 stroker with HP exhaust manifolds, 2.5" exhaust with Hemi mufflers, 3.23 gears 727 standard convertor, a true street engine. More concerned with torque numbers below 3000 RPM. Only question will the 274 be too small in a 512 ci and would the 284 idle and act like the 274 in a 512.
Wondering if you have ever built a 512 with the same lowely street spec?

pm sent

[Challenger340]

Bob,
     The 274 Cammed 440 did you guys dyno the engine with the HP Exhaust manifolds? Seeing as this engine spec would more than likely be fitted in a "Stealth" engine bay was wondering the torque /hp loss (Torque more important as if we are serious the engine on the street spends most of its time from idle to 3000 RPM, torque is what we like on the street).
I am just about to start a build same engine as the 274H 440 but as 512 stroker with HP exhaust manifolds, 2.5" exhaust with Hemi mufflers, 3.23 gears 727 standard convertor, a true street engine. More concerned with torque numbers below 3000 RPM. Only question will the 274 be too small in a 512 ci and would the 284 idle and act like the 274 in a 512.
Wondering if you have ever built a 512 with the same lowely street spec?

Yes, on one of the Collection's examples...
we've exceeded 500hp using the factory HP Manifolds and 2 1/4" Exhaust, WITH the factory Air Cleaner installed, on a NON-Stroker 440 +.030" Engine using Ported Stealth Heads and a custom grind Hydraulic Roller Camshaft
so...
I see no reason you could not easily reach your goals with gunga Trq down low on the 512, with the qualification to access Porting/Flow data on the particular Head R&D adequate for custom Cam selection.

[Challenger340]

Not much time to revisit these old 440 builds, but as a result of some sb Chev 355 "restricted" Sprint Car Cylinder Head R & D....
We've apllied an updated V/Seat application for the Stealth Heads, that doesn't require the same porting/time/money and expense(10-12 Hrs) that we used to imput on the "lowly 440" Pkg

Long story short:
I'll get a before/after Flow Sheet on the STEALTH's up soon,
and,
the resulting .030" over 440 Dyno Sheet.

But we've been able to shave our time imput on the Heads within 4 Hrs Labor floor to floor, then Bolt 'em on with NO Intake or Head Intake/Exhaust Opening Porting(lousy OOTB Port Match)
and
we saw 504hp @ 5,400 rpm, and 525 Ft/Lbs on the Dyno, WITH the Air Cleaner INSTALLED(N96 style Oval 4 BBL)

Pkg update skinny:
STEALTH Heads, changed seat prep/angles/check guides/Bowl blend ONLY after the seat cutters, Valves back cut(4 hrs floor to floor)(NO runner or entrance Porting). Intake Flow averages were much improved.
Stock Stamped Steel Rockers/Shafts
Comp Cams XE284H
Street Dom OOTB
850 cfm Holley
10.14:1

Dunno when we'll get a chance to back this up on a 2nd 440 Dyno Test ? but when/if we can.... or do back it up on a 2nd 440 build, it may move the STEALTH Heads into a basically a very cost effective 500hp Bolt On Head for the "resto" appearance/budget build crowd ?
I'll save the revised seat prep until we back it up on a 2nd lowly 440 build, but I'll order some more STEALTH Heads later today to re-apply/flow again.

[garner7555]

Very interesting.         All the info you have in this thread is incredibly valuable.          Thanks for posting.