What heads does one run with a 511 stroker 400 B block

[Wookie316]

Hi
Some may have seen my thread about my MP P5153524 head that is porous and leaking out the end. I managed to get it stopped and hope it will hold for the summer. Now thinking ahead to the winter when I tear it down to do a correct repair, I am looking for honest opinions on what I should consider switching to with the current build I have. I am not really wanting to switch the cam, but would consider if needed. I am really taking a hard look at the Indy EZ as cast heads, however I understand a person is best to get a set not finished from Indy because of quality control on their end. I am told I am better off to have them finished by a reputable head builder. So the million dollar question is where? Being in Canada it would be nice to have someone up here, but I am not opposed to shipping if needed? What are lead times on average at good machine shops? If I place an order now will I have for the winter to do a swap then?
Looking at continuing running the dual plane as I want to keep everything under the hood. So please give me your opinions on what direction to take this build. Below is the current build as is and what I am looking to accomplish. Thx in advance for your time. Feel free to PM me as well if you wish not to post to forum.

1971 Charger Superbee. 4500 lbs with a full tank and me in it. This is a car that will see mostly street use. I want my build to be one that I am not scared to drive 4 hours to a show yet make as much power as possible with current parts installed without compromising any reliability. Right now I get 16.95 MPG @ 70MPH & 14 MPG @ 80 MPH. Milage isn't a real concern in the build, but that is what it does currently just for information purposes.

MP 452 Aluminum head P5153524 84cc
Comp adjustable rockers 1.5 ratio 1621-16
Comp hydraulic cam 21-228-4 .545 lift 241 intake 247 exhaust
Performer RPM intake
Holley 870 Street Avenger
MSD distributor and 6AL-2 box
Callie's Dragonslayer crank 4.250, 2.750, 2.200
Scat H Beam 4340 Rod 6.535
Custom Diamond Piston 4.375 .990x2.930 Pin -24.0cc #52409 with 84cc it is supposed to be 9.5-1
Cometic Head Gaskets C5461-040
Power Bond Balancer
TTI Headers
3" TTI Exhaust with Magnaflow Mufflers
McLeod Flywheel 464100
McLeod 6913-07 RST clutch
McLeod 1400 series Hydraulic release bearing
Tremec TKO600
3.91 8 3/4" with 27.4" MT's ET Drags 295/45R17

If I have missed any info that is important, please let me know.

 

[GrabberOrange69]

Dude, how are you getting that MPG with that cam and those gears? Imperial gallons?

Well done, it looks great!

 

[IQ52]

Man, if you like it the way it is just put the Edelbrock RPM heads on it. Check with TTI to make sure the RPM heads fit with the headers you have. When we are pressed for time it takes about 30 days to get service prepped heads out, but it could take as little as two weeks from the time the heads get to the shop. Being ready for winter should be no problem.

 

[MikeyT]

I would say big block ones....

:hello2:

Seriously, a nice set of 440source heads

 

[Wookie316]

Yeah that is imperial. I was shocked as well. I was expecting 12-13 @ 70.
Yeah I know Eddy's could be an option as well. Just not sure what to do and since I have time I can get opinions and make a good decision.

 

[benno440]

edelbrock or indys for sure

 

[IQ52]

The OOTB Edelbrock RPM head will out flow the OOTB EZ to almost .600" lift by a substantial amount. The Indy EZ is a better head for a high horsepower build if you port them and take them to max wedge size. But then you can't take advantage of the EZ flows until you use a max wedge port size intake. And they all need to be prepped before use.

Lift...........OOTB EZ.............OOTB RPM..............OOTB Stealth

.100.............66......................73............................73
.200............127....................149..........................151
.300............181....................211..........................205
.400............232....................253..........................245
.500............272....................280..........................262
.600............299....................292..........................276
.700............315....................292..........................281

All flows from the same flow bench. Not outta any book.

If you go to the 75cc EZ head you also pump up the compression ratio.

 

[Wookie316]

The OOTB Edelbrock RPM head will out flow the OOTB EZ to almost .600" lift by a substantial amount. The Indy EZ is a better head for a high horsepower build if you port them and take them to max wedge size. But then you can't take advantage of the EZ flows until you use a max wedge port size intake. And they all need to be prepped before use.

Lift...........OOTB EZ.............OOTB RPM..............OOTB Stealth

.100.............66......................73............................73
.200............127....................149..........................151
.300............181....................211..........................205
.400............232....................253..........................245
.500............272....................280..........................262
.600............299....................292..........................276
.700............315....................292..........................281

All flows from the same flow bench. Not outta any book.

If you go to the 75cc EZ head you also pump up the compression ratio.

So am I better to get a set of Eddy's or Stealths worked over in my build? Am I going to see any gain over the 513/608 I make now? Thx.

 

[Gpuller]

I'll take your old MP ones if your just going to throw them in the aluminum barrel. :glasses10:

 

[IQ52]

So am I better to get a set of Eddy's or Stealths worked over in my build? Am I going to see any gain over the 513/608 I make now? Thx.

Well, we built a 493 with the 4.15 stroke, 4.35 bore combination using service prepped RPM heads, the same cam and intake as yours with an old 750 cfm Holley and it made 565 HP @ 5300 RPM and 635 LB-FT @ 3500 RPM. You can't race dynos but that is what it did on that dyno.

 

[383man]

I use the standard EZ heads I bought from Dwayne Porter. He did a little clean up porting on them and also gave me a good price. I like the standard EZ's as they use the stock geometry rockers and the exh is in stock location. They flowed 329 @ .600 lift and work great on my 493. The eng pushes my 3700 lb 63 to 10.70's so far. I had to use these dished pistons from 440Source to have pump gas friendly 10.6 comp and I built good .046 quench in it. Runs great on 92 pump and I race it like I drive it thru the pipes on pump. But I am very pleased with my EZ heads I bought from Dwayne Porter. They have been on the eng since June 2011. Ron

 

[Bigal75]

I would go with EZ's as well.

 

[IQ52]

Hey there is no doubt the EZ Heads will work. We have a ported pair here we slapped on a 440 dyno mule running a stock crank and rods and TRW forged 6-pack pistons. With an old Racer Brown roller cam ground in 1968 it made 658 HP and with a Comp Cams XE285HL it made 595 HP. We pulled 787HP with Edelbrock RPM heads on a 451 and 91 octane. Anything will work if you put it together correctly.

 

[Propwash]

So am I better to get a set of Eddy's or Stealths worked over in my build? Am I going to see any gain over the 513/608 I make now? Thx.

I'd listen to IQ52. As far as power gains, good breathing eddy heads would open the bottled up HP/TQ. My 512 build is pretty similar to yours (w/eddy heads). Cam is just about identical as far as lift/duration, but I'm running a solid flat tappet, and a tad bigger quickfuel carb. Also running about 100 more HP and Torque. I would think a nice ported set of eddies would bump up your 513/608 nicely.

 

[Wookie316]

Yeah the MP's were when my plan was to just add cam and heads to a stock 400. Now that my build grew I always knew I wanted to upgrade the top end. Just didn't think it was going to be so soon! I know I have more HP in this beast, so now I am looking to release it and go a direction that is going to work best for me.

 

[super-bee_ski]

As IQ 52 suggested and NOW Edelbrock has the new Mopar Performer head available...

 

[Supershafts]

Id put the bigger Indy head on it and get another cam and be well beyond that 513 hp mark.

You have a heavy breathing bottom end and are giving up quite a bit with smaller ports, quite a lot a bit

 

[Wookie316]

Question? Since the Indy EZ head sits above the valley deck, does that raise the intake manifold any amount? If so how much? Need to keep my build under the hood. Thx.

 

[Kern Dog]

Holy CRAP that is a beautiful car! I see you have the Comp XE285HL cam. I ran that one and did like it. Unfortunately I ran regular engine oils and wiped out TWO of those cams before I heard about the problems associated with todays oils!
I have no doubt that with better oil, any cam will have improved chances against failure.

 

[Supershafts]

Question? Since the Indy EZ head sits above the valley deck, does that raise the intake manifold any amount? If so how much? Need to keep my build under the hood. Thx.

Oh that's gonna be a issue, considering id also use the bigger intake. In my car which i moved the motor back a few inches and down a couple or few inches i didn't have room for an air cleaner.... and ALWAYS always use an air cleaner.