aluminium head questions

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A 440 with iron heads, 500 hp, and very streetable; call Dvorack Racing in Waldo, Fl .We can't believe the engine he is building for us, visited twice, see it happening. Call Dan. Google his national records. Price good.
 
You guys make some good points about keeping the iron heads and possibly adding nitrous. I agree that I can reach the same goals and save money going that route.

I've made up my mind on going w/ AL heads though... I like the increased flow, lighter weight, hopefully better sealing valve covers and dry header bolts. I also feel like the heads will help it take advantage of a bigger cam (hence the switch to the roller).

I really like the looks of the 6 pack setup though. If I'm only leaving 10 -15 hp's on the table it's probably not worth it to me to switch. I'll probably leave it on initially w/ the new heads and cam and see how it runs before I try a 4 barrel.

Any thoughts on the cam selection?
 
What gear ratio and tire size? Car weight? Overall taget goal of the car and it's performance?
 
I've got a 505" RB with a factory sixpac with some tweaks running around here. He has a factory shaker hood and wanted the car to stay externally "factory". It makes around 550hp, just shy of 600tq with cleaned up RPMs and a solid flat tappet. With a 4sp it's a torque monster to drive and will spin the tires in 3rd at 55mph with 3.54s if you nail it. That intake was only gasket matched and the carbs use the ProMax jet plates. Otherwise it's just a well tuned factory six pac. If you get Stealths, be careful on gasket choice (use Source's and factor in it's thickness when designing the engine), and assume the springs, retainers, and locks will be tossed. Modern Cylinder Head (in MI) has a good program for them and Jeff does outstanding work for fair price.
 
Gear is a 4.10 w/ 27" tires. I have a 3.55 I can swap in for street driving if the 4.10 gets annoying (and it does above 55 mph). Car weighs 3400. I'd like to get into the mid to high 11's. 550hp would be awesome but I'd be happy w/ anything over 500.

I can spin the tires at 20 mph or so but not much above that.

I've got the vacuum outboard carbs and the only tunning I've done on them (besides idle mixture) is change the vacuum springs to get rid of the bog it had off then line. It runs good but I'm sure there's more there for someone that knows what they're doing. I've contemplated adding the Promax metering plates but wasn't sure if it was worth it or not.

I'm talking to Modern Cylinder Head about CNCing the MP heads. They have a program for the Eddy's and this is the same head.
 
I've run 100's of pounds of NOS.
Some thoughts on it.
You never run out of ported heads.
Hard parts never leaving you running to the NOS filling station.
Having 10 bottles taking up room in your trailer.
Don't get me wrong I like Nos,but in the long run it's not cheaper than building all motor.
 
440+6scamp said:
Now I'm not so sure... I'm finding a lot of posts like this:

http://www.cuda-challenger.com/cc/index.php?topic=52902.0

I know that's just a few folks opinions but the exposed gasket and dropping valve issues seem to be repeated on several forums.

So, back to the MP heads. Everyone claims the "452" head (5153524) is the same thing as the Edelbrock RPM (in fact made by Edelbrock w/ a Mopar logo) but w/ straight plugs.

What about the MP 4876311? I can't seem to find any feedback about it. I would think it's a better choice since it has a smaller, closed chamber. Do people not prefer the factory 906's over the 452's for the combustion chamber? Why is so much made of the "452" Edelbrock copy head but so little mentioned about the "906" 4876311 head?
Click to expand...

I know you already picked a head but the 311 I don't think is available anymore , the new 452 replaced it. The 311 is basically a stage 6 head with stock port locations. I have a set that are ported, they flow roughly 290 cfm at .600 lift. Don't believe any of the quoted numbers from the sellers, actual tests on production pieces show less flow, as much as 30cfm.

you asked this .... What's the length difference in flat vs hyd lifters? Will I have to change pushrods? , if you go to a roller cam you will need pushrods , adjustable rockers if you don't have them , a bronze distributor drive , a cam button , stiffen the stock timing cover , cam and rollers , about 1300 to make the switch .

How far in the hole are your pistons currently ?
 
440+6scamp said:
I've got the vacuum outboard carbs and the only tunning I've done on them (besides idle mixture) is change the vacuum springs to get rid of the bog it had off then line. It runs good but I'm sure there's more there for someone that knows what they're doing. I've contemplated adding the Promax metering plates but wasn't sure if it was worth it or not.

I'm talking to Modern Cylinder Head about CNCing the MP heads. They have a program for the Eddy's and this is the same head.
Click to expand...

The metering plates would be a good idea as it will allow you to make jet changes to tune in the setup, the billet throttle plates also allow you to ajdust the idle screws that are sealed on the stockers without haveing to pull the carbs .

I was going to suggest the mordern CNC program , it also works on the stealths because they are just a copy of the ebrock heads .
 
I'm not sure how far in the hole the pistons are. That's the 1st thing I'll check when I pull the heads.

You're right about the 311 heads. I'm going to go w/ the 524 now. I'll send them to Modern.

I've already purchased a Cloyes hex-adjust double roller timing set w/ a thrust bearing and cam button. I also ordered a bronze gear.

As for a cam, I think I'm going to go for the next step up from the one I have listed:
Comp XR286HR... 236/242 duration, .580/.570 lift w/ 1.6 rockers

My current cam is a 230/236 duration w/ the same lobe separation as the one above. It has .521/.524 lift w/ 1.6 rockers. It idles great (750 rpm easily) w/o much of a big cam lobe to it. I want to go to the roller for the added lift now that I'll be able to flow more air. I figured I'd bump up the duration a little too to get more of a lobe to the idle. The lift is almost the same b/w the 230/236 and 236/242 roller cams. Will I gain much by the added duration or would I be better off w/ the lower duration to increase dynamic CR (my static probably won't be over 10.0)?
 
I think so too and with the 1.6 rockers....cooool man, cool. The increase in duration is small and will be a minor moving up the powerband.
What are the overlaps between the 2 cams?
 
Cost to go to a roller cam on my race car.
Cam $350,over .700 lift
Lifters $500
Push rods $160
Springs Retainers locks lash caps $500
More head work,$500
T&D rockers $1269,needed for cam,spring and head combo.
All this to get 1/2 second.

T&D rockers ie race car ****
Unknown.jpg


2011-02-10_12-43-20_295.jpg


Took off Crane rockers because they won't work on the Indy heads I have,the geometry was off.
These are the rockers that came from Muscle Motors and they were not right from them.
So remember check everything twice,I ran this engine 200 pass's and bent 6 push rods.
The sweep over the valve tip was off.

These are the diff rockers we tried.
0902001018.jpg


Wrong rockers,retainers,locks and rockers.Mass $$$$ mistake.
0902001018a.jpg
 
Thanks for the pics and good info. I currently have the 440source adjustable rockers and figured I'll be able to retain them (MP heads use stock rockers). Is there any reason these rockers w/ be subpar for the mods I'm making?

What lifters would you recommend (that fit the stock lifter bores)?

Lobe separation on all the cams (my current flat tappet and all rollers in consideration) is the same (110).
 
Roller lifters in above picture won't work had to go to $900 lifter because of the over the nose spring pressure.IE 720 lbs.
 
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