How Much HP/Torque for decent street charger

[guywantscharger]

Got a standard 74 dodge charger. Want to do it up and have some decent power for street car. I want it too go like a charger should with great power and noise, however I have no idea when it comes to cars. If I put bigger engine, I would then need to upgrade diff, Brakes. Just want most suitable hp amount for good street car.
Any suggestions on what you would recommend. I have the 440 engine, out of a fury I think (78)
What do you all think is enough Decent HP?

[Ghoste]

A nice rebuild on the 440 to 1969 specs with a little more compression, Edelbrock heads and a slightly better cam will give you more than enough happy.

[skip68]

It's really an individual thing.  Some guys are more than happy with 300HP for the street.  Then there's other guys that feel 600 or 700HP isn't enough.      if all you need is a nice rumble from the motor and ability to smoke your tires once in awhile then I'd say in the 350 to 400 HP is fine.  You can always change gearing for better performance (quickness) without more engine upgrades.  
Keep in mind that just because one guy has 400HP and his car seems slow, another guy can have the same 400 HP and be really quick and seem to have way more power.   It's all in the build and gearing  

[400sforever]

I built my 74 charger with a 400 that we stroked out to a 512 cubic inch. It has a cheetah manual valve body in the tranny with a 3.91 sure grip. Definitely the nastiest street charger around my parts. Never been checked but I know it's around the 600 hp mark.

[Stegs]

i just redid my 440

9.5 compression

stock pistons, stock rods, stock bottom end

stock 906 heads with a port and polish

new cam, but a stock spec cam

firecore igniton, with a eddy performer intake....the power is good...the 440 torque is wonderful

more than enough to get you in trouble....


But, I must admit, horsepower is addicting...im already thinking a slightly bigger cam, and some heads for next year 

[Ghoste]

So guywantscharger, what are your plans for the car?  The real usage you expect to see.

[Challenger340]

A nice rebuild on the 440 to 1969 specs with a little more compression, Edelbrock heads and a slightly better cam will give you more than enough happy.

just for informational purposes....

There is NO stock "CAST" Piston availability anywhere in the marketplace, OEM or aftermarket..... to rebuild the 440 short block to "1969 specs", using an 84 CC Eddy Head, little-lown any open chamber cast iron head.... NOT even close
To attain "69 specs" with any Cast Rebuilder Piston is impossible..... without/requires substantial Block and Head Milling..... that then requires an adjustable Valvetrain to compensate for the bottomed out lifters.

If you have a "stock" Valvetrain and Rocker Arms, and CAST Pistons, and it RUNS.... you are an 8's:1 Engine (although you may believe whatever you want).

The only/first and cheapest viable Piston option available....  targeting the mid 9's:1 or better "1969 440 Magnum spec" with open chamber "906" or other iron heads is the L2355 FORGED Piston from speed pro if you are planning stock valvetrain on '69 spec to keep costs down.

[68pplcharger]

It's really an individual thing.  Some guys are more than happy with 300HP for the street.  Then there's other guys that feel 600 or 700HP isn't enough.      if all you need is a nice rumble from the motor and ability to smoke your tires once in awhile then I'd say in the 350 to 400 HP is fine.  You can always change gearing for better performance (quickness) without more engine upgrades.  
Keep in mind that just because one guy has 400HP and his car seems slow, another guy can have the same 400 HP and be really quick and seem to have way more power.   It's all in the build and gearing  

For me it's about 1100hp... 

[Challenger340]

i just redid my 440

9.5 compression

stock pistons, stock rods, stock bottom end

stock 906 heads with a port and polish

new cam, but a stock spec cam

firecore igniton, with a eddy performer intake....the power is good...the 440 torque is wonderful

more than enough to get you in trouble....


But, I must admit, horsepower is addicting...im already thinking a slightly bigger cam, and some heads for next year 

Piston availability, and careful selection therein.... is paramount to any rebuild when assessing the "goals" in the Engine output, both initially and regarding future upgrades if any are contemplated ?

I know of NO available aftermarket "Cast".... or "stock" replacement Piston available today....  that can yield anywhere even close to 9.5:1 C.R. on stock cast iron open chamber heads, without extensive, and EXPENSIVE MILLING to either the Block and Heads, and/or Valvetrain & Rocker Arm upgrades to then compensate for that extensive Milling that bottoms out the Hydraulic Lifter plunger....
not to mention...
expensive Intake Manifold Milling to correct fitment.

The double-whammy to poor Piston selection initially, if later upgrades are contemplated like "Aluminum Heads" for example.....
is that Aluminum Heads and low Compression Ratios are DISASTEROUS for power output....
due to the Aluminums higher dispertion of combustion heat...
then compounded,
by any Cam upgrades longer duration events.... further dropping cylinder pressure further.

IMO,
the first.... and cheapest... and ONLY piston available for 9.5:1 C.R. on "stock '69 specs" for a 440 Engine is the L2355F Forged Pistons from Federal Mogul.

IMO,
INITIAL PISTON SELECTION FOR THE ENGINE IS CRITICAL !
because really... there is no way to go back and correct later without re-doing everything all over again.

[Ghoste]

Shouldn't a rebuild be leaning to a forged piston for any performance application though?  (by performance I mean anything better than standard pedestrian use)

[Challenger340]

Shouldn't a rebuild be leaning to a forged piston for any performance application though?  (by performance I mean anything better than standard pedestrian use)

The 1968-1970 375 hp 440 Magnums, and 390hp 440 6- Pack Engines used "cast" pistons back in the day, and piston failures were very UN-common .

Today,
and specific to BB Mopar owners unfortunately, due strictly to parts un-availability..... there really are no other choice for a "performance" rebuild, other than to default to a Hypereutectic or Forged Piston offering to get an adequate Compression Height piston for a performance type build. (2.035 C.D. "Flat Top Piston or 2.061" C.D. FT W/4 valve reliefs)

If a suitable cast Piston was available for the 1968-1970 440 Magnum ..... in a conduscive Compression Height(see above)... plenty strong enough and they could be used, but alas, they just are NOT made anywhere..... by anybody.

Part of the problem, and the main reason the mis-information is still out there.... is the aftermarket "rebuilder" Piston manufacturers themselves are perpetuating the myths in their Catalogs.... by listing a "low" and a "High" 440 piston offerings which confuses unsuspecting readers of a "high" compression.
When in fact at 1.92" C.D. for the LOW Piston .... and 1.99" C.D. for the HIGH Piston.... BOTH Pistons are low compression... , one is just lower than the other !
meaning,
that for any real performance 440 rebuild attempt, if either the LOW or HIGH Piston is selected, all you are doing is building a 1972-1978 smogger engine at best even with the HIGH Piston offering ?

Default then is to the L2355F FORGED offering, NOT for it's obvious strength perspective(it is stronger)..... but because it is about the cheapest and ONLY way to get an actual 9.5:1 on a cast iron head.

[Homerr]

I think most people are mistakenly thinking they want HP for street use.  What they really want is torque.

[Ghoste]

And reliability.

[charge69]

My brother used to drag race the old Kawasaki900/1000 motorcycles of the '70's and early '80s in sanctioned drag races and even had a shop specializing in them. He said they were easy to hotrod and basically bullet proof. Called them the "327" of motorcycles back then.

Anyway, he explained it this way:  HP is speed in the quarter, Torque is Elapsed Time!   His street cycle was a mid-'70's Kawasaki 900 bored to about 1015 and custom head-work and, even in full-street trim with both rear view mirrors on it, he would turn low 10's @ about 130mph !  This was late '70's and this was a fast motorcycle!  

He always said getting it off the line was the easy part, the "big end" was the scary point as you accelerated past 130mph and the front end started to get very light!

Remember:  MPH is horsepower    Elapsed time is Torque !  Works for me.

[66FBCharger]

Shouldn't a rebuild be leaning to a forged piston for any performance application though?  (by performance I mean anything better than standard pedestrian use)

The 1968-1970 375 hp 440 Magnums, and 390hp 440 6- Pack Engines used "cast" pistons back in the day, and piston failures were very UN-common .

Today,
and specific to BB Mopar owners unfortunately, due strictly to parts un-availability..... there really are no other choice for a "performance" rebuild, other than to default to a Hypereutectic or Forged Piston offering to get an adequate Compression Height piston for a performance type build. (2.035 C.D. "Flat Top Piston or 2.061" C.D. FT W/4 valve reliefs)

If a suitable cast Piston was available for the 1968-1970 440 Magnum ..... in a conduscive Compression Height(see above)... plenty strong enough and they could be used, but alas, they just are NOT made anywhere..... by anybody.

Part of the problem, and the main reason the mis-information is still out there.... is the aftermarket "rebuilder" Piston manufacturers themselves are perpetuating the myths in their Catalogs.... by listing a "low" and a "High" 440 piston offerings which confuses unsuspecting readers of a "high" compression.
When in fact at 1.92" C.D. for the LOW Piston .... and 1.99" C.D. for the HIGH Piston.... BOTH Pistons are low compression... , one is just lower than the other !
meaning,
that for any real performance 440 rebuild attempt, if either the LOW or HIGH Piston is selected, all you are doing is building a 1972-1978 smogger engine at best even with the HIGH Piston offering ?

Default then is to the L2355F FORGED offering, NOT for it's obvious strength perspective(it is stronger)..... but because it is about the cheapest and ONLY way to get an actual 9.5:1 on a cast iron head.

Great info!
What is the down side to a forged piston vs. a cast piston? Could a six pack/six bbl. piston be used?What are the disadvantages to using the six pack pistons?

[Ghoste]

Speaking out of turn, but I thought the Six Pack pistons were the same as any other 440 hp piston.  The rods are bigger but I thought pistons were the same?

[68pplcharger]

I think most people are mistakenly thinking they want HP for street use.  What they really want is torque.

Definitely debatable and more of a personal preference. I personally like both...   Then it's up to how talented you are with your right foot and your knowledge of your cars characteristics. Also how good you are at setting up the chassis. 

[ws23rt]

I think most people are mistakenly thinking they want HP for street use.  What they really want is torque.

Definitely debatable and more of a personal preference. I personally like both...   Then it's up to how talented you are with your right foot and your knowledge of your cars characteristics. Also how good you are at setting up the chassis. 

Ones personal preference for how a car feels with an engines power really comes down to gearing. At what speed do you want to feel the kick?

Transmissions, rear gearing, etc. are just torque multipliers.  Horse power is a measure of how much work is being done. A heaver car will require more hp than a light one to accelerate.

I like charge69's way of looking at torque and hp.---mph is hp (work being accomplished).--torque is et. (the work happened faster).   Torque get's you up to speed and horsepower holds the speed.

BTW I still have my 73 900 Z1.  55K on it and the engine was running strong when I last road it.

[Challenger340]

Shouldn't a rebuild be leaning to a forged piston for any performance application though?  (by performance I mean anything better than standard pedestrian use)

The 1968-1970 375 hp 440 Magnums, and 390hp 440 6- Pack Engines used "cast" pistons back in the day, and piston failures were very UN-common .

Today,
and specific to BB Mopar owners unfortunately, due strictly to parts un-availability..... there really are no other choice for a "performance" rebuild, other than to default to a Hypereutectic or Forged Piston offering to get an adequate Compression Height piston for a performance type build. (2.035 C.D. "Flat Top Piston or 2.061" C.D. FT W/4 valve reliefs)

If a suitable cast Piston was available for the 1968-1970 440 Magnum ..... in a conduscive Compression Height(see above)... plenty strong enough and they could be used, but alas, they just are NOT made anywhere..... by anybody.

Part of the problem, and the main reason the mis-information is still out there.... is the aftermarket "rebuilder" Piston manufacturers themselves are perpetuating the myths in their Catalogs.... by listing a "low" and a "High" 440 piston offerings which confuses unsuspecting readers of a "high" compression.
When in fact at 1.92" C.D. for the LOW Piston .... and 1.99" C.D. for the HIGH Piston.... BOTH Pistons are low compression... , one is just lower than the other !
meaning,
that for any real performance 440 rebuild attempt, if either the LOW or HIGH Piston is selected, all you are doing is building a 1972-1978 smogger engine at best even with the HIGH Piston offering ?

Default then is to the L2355F FORGED offering, NOT for it's obvious strength perspective(it is stronger)..... but because it is about the cheapest and ONLY way to get an actual 9.5:1 on a cast iron head.

Great info!
What is the down side to a forged piston vs. a cast piston? Could a six pack/six bbl. piston be used?What are the disadvantages to using the six pack pistons?

The downsides to a Forged Piston used to be fitting them with more running clearance and "noise", but with today's alloys and cam & barrel skirt designs it is minimal.

The L2355F is a copy of the original '68-70 six pack Piston, albeit "forged" construction.

No dis-advantages really to using the six pack piston whatsoever, other than it is heavy(stock weight). And at the 2.061 Compression Distance with 4 Valve reliefs(7 CC's), when used with most cast iron open chamber heads(86-88 CC's) and a composition style head gasket(11 CC's) on an UN-milled block(.020"down from deck is 4.8 CC's) , it yields about a perfect mid 9's Compression ratio.
(7 + 86 + 11 + 4.8 ) = 108.8 CC Clearance Volume
.030" over 440 = 914 CC's
914 + 108.8 = 1022.8 / 108.8 = 9.4:1

Now, consider any kind of performance aftermarket Camshaft addition to the mix, even a small CompCams XE274H with an Intake Valve closing event of around 65* ABDC, and you are still only making around 145 psi, which is about MINIMUM for that Camshaft to work well, and plenty safe for pump premium fuel.
 

[68pplcharger]

I think most people are mistakenly thinking they want HP for street use.  What they really want is torque.

Definitely debatable and more of a personal preference. I personally like both...   Then it's up to how talented you are with your right foot and your knowledge of your cars characteristics. Also how good you are at setting up the chassis. 

Ones personal preference for how a car feels with an engines power really comes down to gearing. At what speed do you want to feel the kick?

Transmissions, rear gearing, etc. are just torque multipliers.  Horse power is a measure of how much work is being done. A heaver car will require more hp than a light one to accelerate.

I like charge69's way of looking at torque and hp.---mph is hp (work being accomplished).--torque is et. (the work happened faster).   Torque get's you up to speed and horsepower holds the speed.

BTW I still have my 73 900 Z1.  55K on it and the engine was running strong when I last road it.

Agreed it definitely matters how the car is set up, but a true street car would generally be set up for cruising etc. and you are limited to the gear ratios if you really spend a lot of time on the road and expect reliability. I know the pros and cons of both low end torque vs high end horsepower. I've been building these things for thirty years. That's why I like forced induction on a V8 you can have the best of both worlds. You can feel the kick at any speed... 

[Challenger340]

Speaking out of turn, but I thought the Six Pack pistons were the same as any other 440 hp piston.  The rods are bigger but I thought pistons were the same?

Nope.
The 440 "Magnum" Pistons from '68 to '70 were the same as any other 440 grocery-getter, a 2.035" Compression Distance Flat Top design(about .055" down from deck), advertised as 10:1 (13.2 CC downfill volume)
and,
The 440 "six-pack" pistons were a 2.060" Compression Distance Flat Top with 4 Valve Reliefs (about .020" down from deck), advertised as 10.5:1 (9.7 CC downfill volume)

In actual production, none of the above actually met those compression numbers... they were "targets", with most leaving the door .3 to .4 lower.

Anybody reading this..... starting to see why so many so-called "numbers matching" perfectly restored 440 magnum and six-pack cars, that have had the engines rebuilt using TODAYS stock replacement 1.92" and so-called "high" 1.99"Compression distance pistons are such FAWKING DAWGS !

[skip68]

  thanks 340.  Good info.   

[charge69]

"Slight Hi-jack"     Hey ws23rt,  I had a 1974 Z900 and loved it. Very reliable, fast and, just a great looking classic bike.  As with most bikes of that era, they could be evil handling if you pushed it too much in the twisties but were awesome bikes for leisurely cruising the back roads or making into a 1/4 mile drag bike! I miss my old Z-1!

Also, that was my brother who told me about Torque and Horsepower and it still rings true today!

[66FBCharger]

I thought I read several months back that a replacement cast 440 piston (with the correct compression distance) was going to be available soon. Did I read that or dream it?

[Challenger340]

I thought I read several months back that a replacement cast 440 piston (with the correct compression distance) was going to be available soon. Did I read that or dream it?

No, your read it.
I investigated having 30 sets built through a manufacturer, even went as far as the engineering drawings off the blanks....
Problem is,
that's one hell of a cash outlay with very little chance to ever sell them and recoup the money..... when as evidenced here even on this site, we can't even convince ONE GUY who is rebuilding his 440 that he needs them ?
because,
Manufacturer Catalogs, and dumb engine machinists reading those same Catalogs with questionable math skills, are still stuck in their "myth"  mentality.

The stoopidist part of the whole fiasco....
is that in my conversations with the SAME company's piston engineer that is currently producing the terd 1.92" & 1.99" pistons.... he agreed 100% with my calculations.... and admitted point blank their current Pistons(1.92"  & 1.99")  are much lower compression than advertised ?
But who cares ?
Why change ?
Hundreds of these Engines rebuilt and running around with them... the owners certainly don't "how" they are supposed to perform ?

So, for me it was why spend thousands, and thousands more in marketing..... trying to educate the UN-educatable who are just going to go buy the 1.92" and so-called "high" 1.99" Pistons anyways ?
You can lead a horse to water.... but ya can't make the damn thing drink.