Sticking with cast heads for build.

[BSB67]

I think it's interesting that stock Street Hemi's in 3900# B-Bodies, rated at 425 HP and 490 TQ would run the 1/4 mile with 3.23 and street tires around 13.7 and 103-104 mph.

Right.  Factory numbers were somewhere between a little to a lot over inflated, usually by the time they got the car to the magazines they were in less than perfect tune, and if you get the details of the test run, they usually had some on board equipment and/or a second person. They usually came in at well above 4200 lbs.  And of course, the 60 ft times were not reported which has the biggest impact on et.  A 103/104 mph w/ a 2.0 to 2.05 60ft. will net a 13.30 to 13.40 unless something silly is happening mid track or a fuel problem on the big end..

[Canadian1968]

Well I get the idea, if I want to keep the iron heads, i am gonna pay some $$$ to get them to flow enough to hit 500HP.  Easily more than a set of Stealth heads.  

Now back to my question that I asked,  what kind of HP/TQ should I aim for if I want to hit 13s flat. Keeping 3.23 gears.  

FORGET the Head Flow...
until,
you figure out WHAT MANIFOLDS you want to use to utilize that FLOW... or allow the exhaust to get out ?
For ANY E.T. or Gearing.

I know 13 flat ( if I could dip into the 12 I would not be upset!) is nothing crazy but that is why I want to aim for it. I know it is do able with reasonable ease.

The headers area hedmans 1 3/4 with a 2.5 x pipe all the way to the back .  I was looking at a Holley street dominator , but with my lowered HP goals I think I might not have the motor to make use of the single plane?? In which case I would look at the eddy rpm dual plane.  The carb I have right now is the Holley 750 .

[firefighter3931]

I know 13 flat ( if I could dip into the 12 I would not be upset!) is nothing crazy but that is why I want to aim for it.

"I know it is do able with reasonable ease"

It's harder than you think 

The 3.23 gears are going to hurt, especially with a heavy car. You need torque multiplication to effectively launch the car and keep it accelerating down track. You're going to need descent tires so it'll 60ft properly. Weight transfer with suspension mods to plant the back tires is very important as well. 



Ron

[Canadian1968]

Sounds like higher gear is strongly recommended ?? 3.55 ??

[BSB67]

You absolutely do not need a different gear!!!!

I do agree that it is not a walk in the park.  But good planning it wont be hard.  

If you want to change gears, converter, and tires, make that part of your plan.  If your goal is 13.0, and you have not built the engine, it does not make sense to me that you would build a motor that was short 30 hp of your goal, and you then purchase $2,000 of suspension parts to achieve your goal.

The information that I posted was not theoretical or read in a magazine.  Call it what ever horse power you like, but if you make enough power to go 106 - 107 you'll be right the at your goal.  The 2.0 60 ft will take a little practice if you are using a small BFG type street tire.  Also notice that in my earlier statement there was a qualifier....DA <2000 ft.  If you are wanting to run a 12.80 at 3500 ft altitude, on a 95° F day, it will take a lot more power than running a 13.0 at Atco (about sea level) in the fall.

Build a solid 440 with 9.5 to 10.0:1 CR (iron head) with quench.  This will be a bit of a PITA with 906 heads.
Good set of heads with comp valve grind and ported to flow 260 at .500" lift.
Use the RPM intake and headers with a mandrel bent 2 1/2" exhaust system and ultra low mufflers.
Use about any decent cam with 230 to 236° intake lobe measured at 0.050" would work.  I would use a LSA of 110 or maybe 112.

I like to add adjustable rockers to everything that I build. But I have friends that have done what you are trying to do with the factory stamped steel.

The problem I see with this combo is the 906 heads.  If you build this motor, your short block will be set up for 906 heads unless you change pistons.

There are a bunch of other ways to get to your goal.  This is what I would recommend.   You could skip the porting and add a bigger cam, as an example.

If you would like for me to give you the details of several different combinations that have met you goal, let me know.

[Canadian1968]

You absolutely do not need a different gear!!!!

I do agree that it is not a walk in the park.  But good planning it wont be hard.  

If you want to change gears, converter, and tires, make that part of your plan.  If your goal is 13.0, and you have not built the engine, it does not make sense to me that you would build a motor that was short 30 hp of your goal, and you then purchase $2,000 of suspension parts to achieve your goal.

The information that I posted was not theoretical or read in a magazine.  Call it what ever horse power you like, but if you make enough power to go 106 - 107 you'll be right the at your goal.  The 2.0 60 ft will take a little practice if you are using a small BFG type street tire.  Also notice that in my earlier statement there was a qualifier....DA <2000 ft.  If you are wanting to run a 12.80 at 3500 ft altitude, on a 95° F day, it will take a lot more power than running a 13.0 at Atco (about sea level) in the fall.

Build a solid 440 with 9.5 to 10.0:1 CR (iron head) with quench.  This will be a bit of a PITA with 906 heads.
Good set of heads with comp valve grind and ported to flow 260 at .500" lift.
Use the RPM intake and headers with a mandrel bent 2 1/2" exhaust system and ultra low mufflers.
Use about any decent cam with 230 to 236° intake lobe measured at 0.050" would work.  I would use a LSA of 110 or maybe 112.

I like to add adjustable rockers to everything that I build. But I have friends that have done what you are trying to do with the factory stamped steel.

The problem I see with this combo is the 906 heads.  If you build this motor, your short block will be set up for 906 heads unless you change pistons.

There are a bunch of other ways to get to your goal.  This is what I would recommend.   You could skip the porting and add a bigger cam, as an example.

If you would like for me to give you the details of several different combinations that have met you goal, let me know.

Thank you now there is some info to chew on. !!

I am obviously playing with the same factor that everyone else has....... a bit of a budget.  There is not one set in stone,  but if I can keep a few of the parts that I already have, that will work toward what I want, then why not use them !!  If I dont' have to replace every single part of my drive train, I would perfer not to !!!

I am just finishing up rebuilding the entire rear frame / trunk of the car.  I want to be able to drive the car this summer. As posted before I already have the exhuast purchased for the car, ( yes I am actually using ultra flows already ).  The engine will get me threw the summer with out issue as it is now.

BUT !!! I obviously have the rear end out of the car right now, if I need to put in gears , this is the time to do it i realize.  But it is also probably an additional $500 (parts and labour)  that I had not planned on spending before summer.  If I can use other parts of the drive train to help me wiht my 3.23 I would rather do that.

I dont' totally understand the Tire size / gear relation.  I would like to put a different rim/tire combo on there eventually, I like the look of a 16/17" rim.  So going bigger will that hurt or help my Tire/gear ratio??

I am also going to purchase a set of CE adjustable shocks for the front and rear, this should give me a bit help with weight transfer ??


Let go wiht that before, we start talking about the engine again???

[Cooter]

Taller than a 26-27" tall tire will hurt final drive ratio. Example...
3.23 gear with a 26" tall tire = 3.23.....
3.23 gear with say, a 30" tall tire/wheel (like some of those pimp wheels you see), final drive ratio acts like 2.76.....

[Canadian1968]

Ok so if I keep the 3.23 I deffinantly need to keep my over all tire diameter the same

[firefighter3931]

Or if you plan to go with a taller tire....adjust the axle ratio to compensate 

The reason I suggested a deeper axle ratio is becaue most Charger guys use a 275/60 out back. 

275/60 with 3.23 gears knocks it down to 2.99 final drive.

275/60 with 3.55 gears knocks it down to 3.30 final drive

So, using a 3.55 with a 28in tall 275/60 is basicly the same as using a 3.23 with a 26in tall (stock height) tire



Ron

[firefighter3931]

Build a solid 440 with 9.5 to 10.0:1 CR (iron head) with quench.  This will be a bit of a PITA with 906 heads.
Good set of heads with comp valve grind and ported to flow 260 at .500" lift.

While I agree that a 260cfm@.500 will get the job done with a reasonably streetable cam....I'd say you'd be hard pressed to do that for less than the cost of a set of RPM's.....and you'd still be stuck with 40 yr old castings that can crack and also weigh a lot more (50 lbs) than a set of RPM's. 


Ron

[cudaken]

 68, you lost me when you said "I like the look of a 16/17" rim.", yea I am old! But then again, Mom and Dad could not understand why I wanted Bell Bottom pant's either! 

Here is something for you to play with.

http://vexer.com/automotive-tools/speed-rpm-calculator

Gives you something to think and play with.

Good luck with your quest.

Cuda Ken

[c00nhunterjoe]

It can be done. And it can be done on a budget. It all depends on your capabilities and resources and willingness to be meticulous with details. I am doing it with a 383 and "junk" 516 heads. I cant hit 12's every day because like bsb said, when the air quality is horrible and its 100° out i cant do it but on a good evening im in the 12's with my jalopy. Shes a solid low 13 second car every run. Its a 4 speed and a blast to drive. I cruise it everywhere and if i stick to 45-50 mph i can get 11 or 12 mpg. Its super reliable, requires no maintenance other then a yearly oil change and air filter cleaning and turns heads everywhere i go.

[69wannabe]

$1500.00 in a set of iron heads thatmlimit you to 10.0:1 compression. Therefore, limiting power.
not to mention the cost of the heads. (Usually, around $100-150.00 a set)....

Out of the box aluminum heads for $1500.00 that OUT FLOW the iron heads, and allow 11.0:1 compression on same fuel...


Now, you know why.....

Well said Cooter! I am planning on swapping to a set of eddy RPM's when I get my credit card paid down some more!! I have a set of cast big valve heads on my engine now but there are several more advantages to aluminum heads than just having bigger valves and more flow.

[c00nhunterjoe]

Yes, but you dont have to buy aluminum heads to get into the 12's nor do you have to dump a ton of money into iron heads either. Build the rest of yiur engine around your heads. Its more difficult when you are on a tight budget but not impossible.

[firefighter3931]

Yes, but you dont have to buy aluminum heads to get into the 12's nor do you have to dump a ton of money into iron heads either. Build the rest of yiur engine around your heads. Its more difficult when you are on a tight budget but not impossible.

The OP is looking for a mild 440 that will idle at 850 and run a brake booster. 

Joe, your 383 runs well but it has a 509 cam and 1300rpm idle using 4.10's to wind her up....apples vs oranges. 


Ron

[firefighter3931]

Here's a good article by Dwayne @ Porter Racing Heads on cylinder head porting. The post is several years old so the pricing is not current but it gives you an idea of how much work it takes to make a set of factory heads flow as well as a set of "as delivered" RPM's 

http://www.moparts.org/Tech/Archive/bb/40.html


Ron

[ACUDANUT]

Yes, but you dont have to buy aluminum heads to get into the 12's nor do you have to dump a ton of money into iron heads either. Build the rest of yiur engine around your heads. Its more difficult when you are on a tight budget but not impossible.

Very true. 

[Canadian1968]

If I decided to go with the aluminum heads . They will be stealth heads....

[Troy]

If low 13's is all you want... most people can RUN faster than that in sneakers

Sorry, but this has me rolling! 

Troy

[firefighter3931]

If I decided to go with the aluminum heads . They will be stealth heads....

The Stealth is a descent head but it is no RPM   

Out of the box you're leaving 40-50 hp on the table vs an RPM. 



Ron

[moparsr2fast]

    Just my    but i have been a machinist for almost 30 years, and know my way around metal. That being said, i generally will spend around 40 hours porting a set of iron heads start to finish. And while they work very well, it isn't the most fun way to kill time.  My vote is for the aluminum  heads also. 

[c00nhunterjoe]

Yes, but you dont have to buy aluminum heads to get into the 12's nor do you have to dump a ton of money into iron heads either. Build the rest of yiur engine around your heads. Its more difficult when you are on a tight budget but not impossible.

The OP is looking for a mild 440 that will idle at 850 and run a brake booster. 

Joe, your 383 runs well but it has a 509 cam and 1300rpm idle using 4.10's to wind her up....apples vs oranges. 


Ron

My point was you dont need a ton of money to dip in the 12's. If you want it to idle likes its bone stock it will take a little more. So my "budget" suggestion will be to punch the 440 .060 and run a set of kb236's on those stock heads. Run a comp xs282 or maybe 1 step down. In my opinion a small to mild solid will be a better choice then a hydraulic for what he expects out of idle temperment and vaccum. The bottom line like everyone aggrees is if you are going to dump a ton of money to port iron headz just buy aluminum. If you are hell bent on runni g iron heads over aluminum then perhaps looking into a set of max wedge iron heads and really wake up that 440...

[ACUDANUT]

What are max wedge heads going for these days.?  I wonder why they did not make these the standard heads.

[Cooter]

Used to be a time when aluminum heads was considered 'race only' due to price.
now however, it seems that spending $150.00 on a set of iron heads that need by the time your done, around $1000.00 worth of work, when aluminum heads will out flow your port work, for about $300.00 more.

[ACUDANUT]

What are max wedge heads going for these days.?  I wonder why they did not make these the standard heads.

That did not answer my question.