Realistic Expectations - 11 second Demon weekly driver

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xguard

xguard

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Hi,
Been buried in articles and threads. Think I have a combo sorted out. I have a 72 Dodge Demon, full interior, factory suspension, etc.

I'd like to have a low 11 second car that i can drive to work once a week. A "friday car" so to speak. Then drive it to the track after work. 40ish mile round trip.

I've got a 440. Forged factory internals. 915 heads with 2.14 / 1.81 valves. From what I've read that may have been a mistake installing the larger size valves in the 915 head.

So the question is, having proffessional work done on the iron heads i already have vs buying indy ez or trick flow heads.

The rest of the combo is as follows:
Lunati solid flat tappet cam 243/251 @ .050. .546"/.566" lift with 1.5 rocker.
Weiand team G intake.
Holley 850 dp.
3000 stall convertor.
3.55 gears

Thanks for input, tear me a new one if i need it. If this won't get low 11's what's a realistic expectation between the ported iron heads vs mostly ootb indy ez or trick flow 240 head.
 
The use of iron heads has certain draw backs worth considering even though the head could very well be ported to support the power/ET you search for.

Think about it!
Aluminum heads ...

Save 50/60 lbs. off the nose off the car
After a quick check from the machinist, the heads flow very well. Vs porting the iron and all New everything else that it will need to compete with the aluminum head.
Lighter weight helps ET penalty free.

I'm not pooping on the iron head route but .....
 
I have almost the same identical combo. Mine can be daily driven. It's certainly a Friday driver.

440, eddy RPM heads, 242 cam, 950 carb, 456 gears, 3500 stall. Goes 11.70's @114

I wouldn't put a nickel into iron heads. Go aluminum.

That combo may touch the 11's with a decent stock replacement head. It won't go low 11's unless you have some impressive heads on it. Even then the tall gears and low stall are going to hinder you.
 
roccodart440 said:
I have almost the same identical combo. Mine can be daily driven. It's certainly a Friday driver.

440, eddy RPM heads, 242 cam, 950 carb, 456 gears, 3500 stall. Goes 11.70's @114

I wouldn't put a nickel into iron heads. Go aluminum.

That combo may touch the 11's with a decent stock replacement head. It won't go low 11's unless you have some impressive heads on it. Even then the tall gears and low stall are going to hinder you.
Click to expand...

Thanks! Are your heads ported?
 
From the 90's... 440, on hyper flat tops, MP solid .528, RPM intake Holley 750, cheap headers. In a heavier 100% original body B body and 4.10s it went 11.70s driving to and from the track. Pump gas, on 915 heads with 2.14/1.81 valves. He had ported 915s and it would go 11.90s. I ported a replacement set when one cracked. Money wise given the options now, I'd just buy a set of RPMs and have them corrected. They should, out of the box, get the air you need. In terms of your goals... not lofty but you'll need a little more gear and a really well set up suspension to do it.
 
roccodart440 said:
-- That combo may touch the 11's with a decent stock replacement head. It won't go low 11's unless you have some impressive heads on it. Even then the tall gears and low stall are going to hinder you. --
Click to expand...
-- Agree -- Also, shed, all, unnecessary weight - rear seat, heater core & box. radio, possibly go to aluminum radiator, etc. -- 3.91 gears are streetable, around town. -- Low 11s doesn't come easy.
 
moper said:
From the 90's... 440, on hyper flat tops, MP solid .528, RPM intake Holley 750, cheap headers. In a heavier 100% original body B body and 4.10s it went 11.70s driving to and from the track. Pump gas, on 915 heads with 2.14/1.81 valves. He had ported 915s and it would go 11.90s. I ported a replacement set when one cracked. Money wise given the options now, I'd just buy a set of RPMs and have them corrected. They should, out of the box, get the air you need. In terms of your goals... not lofty but you'll need a little more gear and a really well set up suspension to do it.
Click to expand...
RPMagoo said:
-- Agree -- Also, shed, all, unnecessary weight - rear seat, heater core & box. radio, possibly go to aluminum radiator, etc. -- 3.91 gears are streetable, around town. -- Low 11s doesn't come easy.
Click to expand...

I'd like to keep the interior intact. Maybe I'll have to settle for a little slower time. Or go another route
 
You can do 11's with a full interior. You can save weight else where. Fiberglass parts are a hiuge help. Hood and truck lild as well as bumpers are a huge savings.
(I still suggest aluminum heads though it is not a mandatory item.)
 
Sure it can be done. But the car has to stick, and the package has to be well sorted out and matched for a 1/4 mile race. Not highway cruising. If it was easy everyone would be doing it. Remember too - if the goal is low 11s, you will have to have a cage and other safety equipment on it too. So it gets heavier and more expensive. My advice - look to go 11 70s - 11.60s. Then the bar and safety stuf goes away, and the gearing can be more mild. You will still need a really well sorted car. But it gets a bit easier than low 11s.
 
A buddy of mine had a '72 Duster with a worn out 383 in it. He wanted a fresh engine so we built a stock stroke 400 with RPM heads (Stage II porting by Dwayne) and a small Ultradyne roller cam. Car had Hooker fenderwells in it which are crappy but that is what he had. Car had full interior, full exhaust, street tires, all steel, etc. He drove it to work and around town. It was a little lumpy but driveable. Car was deadly fast with the new 400 engine. He took it to the local track and ran a stack of 10.90 @ 122 mph passes until someone he beat complained and he got kicked out since he didn't have a rollbar.
 
Stick it all together in there and run 3.91 gear. Ill bet it goes 11's, and if you want a little quicker... blue bottle and high tens no problem!
 
AndyF said:
A buddy of mine had a '72 Duster with a worn out 383 in it. He wanted a fresh engine so we built a stock stroke 400 with RPM heads (Stage II porting by Dwayne) and a small Ultradyne roller cam. Car had Hooker fenderwells in it which are crappy but that is what he had. Car had full interior, full exhaust, street tires, all steel, etc. He drove it to work and around town. It was a little lumpy but driveable. Car was deadly fast with the new 400 engine. He took it to the local track and ran a stack of 10.90 @ 122 mph passes until someone he beat complained and he got kicked out since he didn't have a rollbar.
Click to expand...

That's exactly what I want! Would the ported heads help much with the cam I mentioned?
 
Spray it! That motor will live with a moderate shot! Get the car to hook and it'll go 11s and still be reliable and fun
 
I drove my 65 Valiant with a 360, 904 and 4.30 every single day for almost fours about 9 miles one way with some interstate driving. It ran consistent 11.40s.

You ain't gonna make it with 3.55s.
 
So even with indy heads (or trick flow or rpm) still need at least a 3.90 gear? Maybe more? What about converter?
 
You just have to figure out how fast you want to go and then put the gear in the car to make it happen. Figure out where your torque peak will be and then where the power peak will be and put the gear in that puts you at the power peak at the stripe. If you car is 3400 lbs you'll need 550 honest hp to run 10.90. It is easy to make 550 hp with a pump gas big block, the trick is getting it to the ground all the way down the track. Here is an article on one of my 470 pump gas engines. This one is 10.5 compression, 4150 carb, wet sump, etc. It makes right at 700 hp which would put you well into the 9's. The cam is probably a bit big for street driving but you'll only lose 40 or 50 hp if you put a smaller cam in it. So that gives you 650 hp with a fairly streetable combo. If you built this engine you would need to gear it so you hit 6800 rpm at the stripe. You'll probably be going 125 mph so the gear ratio you need just depends on your tire size. You'll probably need a 4.10 gear if you have a 26 inch tire. Build a copy of my engine, put the right gear and converter in the car and it will run 10's on pump gas. We Test Intake Manifolds and Carburetors on our 400 Stroker in Search of Ultimate Power - Hot Rod Network
 
It have said this before and mean every word of it, there ain't NO shame in a copy cat engine. You do the owner proud by copying his word. A tried and proven set up in YOUR car. Can't beat it with a stick!
 
Check out the F.A.S.T web site. With my barracuda I WILL have a mid to low 11 sec. street car. With steel heads. It can be done. Don't get me started on NOS lol
 
Mine is a bit different, in that it is 500 cubes, but with a 236/242 541/544 hydraulic roller cam, 750 DP, 3000 stall and 3.55 gears it has run a best of 11.53 with consistent 11.60-11.70's. Full interior and large driver. Very street friendly, I drive it to shows and to and from the race track. I race it right off the street with full 2 1/2 inch exhaust and drag radials. I originally had home ported 452 heads and switched to stock Eddies which picked up about 2 tenths. I would say with fewer cubes and better cam and heads it is still possible to run mid to high 11's.

Me at St. Thomas.jpg
 
xguard said:
So even with indy heads (or trick flow or rpm) still need at least a 3.90 gear? Maybe more? What about converter?
Click to expand...
I ran a bunch of 10.60 in the 1/4 with a 93 pump gas 440 in a 3520 pounds 73 dart swinger. It had 4.10 gears and 28 inch ET street Tires. You could drive it any wear you wanted. It had a 9.5 inch converter that stalled around 4200. But like everybody is saying I would recommend in getting a set of aluminum heads. Mine had a pretty much stock Indy EZ head
 
Xguard... dont let this turn into a witch hunt, everyone will tell you what you NEED, but until you get a solid baseline with some passes and drive it around, IMO theres no point to get aluminum heads yet. Use what you have first, it will be serious handful in an Abody anywho! My dart is an iron headed smallblock, full interior and goes 11.60's
 
rumblefish360 said:
The use of iron heads has certain draw backs worth considering even though the head could very well be ported to support the power/ET you search for.

Think about it!
Aluminum heads ...

Save 50/60 lbs. off the nose off the car
After a quick check from the machinist, the heads flow very well. Vs porting the iron and all New everything else that it will need to compete with the aluminum head.
Lighter weight helps ET penalty free.

I'm not pooping on the iron head route but .....
Click to expand...
go alum. if u can afford it. My alum victor knock offs are only 6 pounds per head lighter than 915`s, not all alum. heads are alike !~
 
What we see here today are good combinations that have one thing in common, big or small block, is that a certain amount of power has to be made in order to get what you want.

A few have done it with iron heads.
 
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