Heads...again

[4eyedblonde]

This kinda relates to my last post regading dist clearance on Edelbrock heads. I have to replace the heads as one is cracked and cannot be repaired. The machine shop has a set of 906 heads. Mine had the casting # 216. I was told these are open chamber heads with 2.1 valves etc. Well ported but not matched to the Performer intake. It's '69, 440.
Question; what are 906 heads in comparison to the 216's I took off? I have the option to go aluminum, or with the cast iron units that are prepped already (ported etc). I have full crane adjustable valve train that is still good to re use on either head.
Is aluminum Edelbrock performer heads the way to go or even the Victors? Or for street use stick with the cast iron?
Cam is the 509 purple stick, flat top pistons..basically a well built bottom end on this 440. This is gonna cost me a **** load so I want to do this right once and I don't have the knowledge for this kind of decision, so please help..anyone

 

[67 B-body]

If your wanting to use the Edelbrock brand, the Victors are certainly king of the Hill....... They do however require special offset rocker arms to keep valve train geometry straight, They have raised exhaust and intake runners, this means that you'll probably ditch the headers you currently have for a set of TTI or equivalent offering the extra length on primary tubes....
The good thing is,,, they do have the ability to be easily upgraded to MAX WEDGE ports, they can flow very high CFM, They have a modern heart shaped combustion chamber, Reduced chamber volume in CC's, and they are aluminum so higher compression works better.

 

[4eyedblonde]

If your wanting to use the Edelbrock brand, the Victors are certainly king of the Hill....... They do however require special offset rocker arms to keep valve train geometry straight, They have raised exhaust and intake runners, this means that you'll probably ditch the headers you currently have for a set of TTI or equivalent offering the extra length on primary tubes....
The good thing is,,, they do have the ability to be easily upgraded to MAX WEDGE ports, they can flow very high CFM, They have a modern heart shaped combustion chamber, Reduced chamber volume in CC's, and they are aluminum so higher compression works better.

Thanks 67 B-body,
I can't change out the headers, they're new Doug's($1000) and I'd have to pull the motor to get them out anyway, which is not in the cards

 

[IQ52]

Unless the head porter can give you a flow bench comparison of his ported 906 heads to the Edelbrock RPM heads that show something different, you will get more flow per dollar from the aluminum heads OOTB than you will get from ported 906 heads. It takes a REAL good head porter to get 290 cfm from the 906 and outflow the RPM.

 

[4eyedblonde]

Unless the head porter can give you a flow bench comparison of his ported 906 heads to the Edelbrock RPM heads that show something different, you will get more flow per dollar from the aluminum heads OOTB than you will get from ported 906 heads. It takes a REAL good head porter to get 290 cfm from the 906 and outflow the RPM.

Understood. This guy is one of the best around up here for porting etc. Unfortunately at this time I can't justify the $2500 for the heads when his C.I. set is $950 plus the 300 or so porting chrg.
I'd like to go aluminum but for a street car, it doesn't make sense to drop that kinda dough..at least outs my wallet lol

 

[Meep-Meep]

I'm not familiar with a 216 head but the 906 head is great on the street with even just a pocket port job. Personally I'd just grab the 906's and run. Why do you need high flowing heads for a mild street car that sees redline maybe once in a blue moon? You live at 3000 RPM on the street so what is 300 peak CFM going to do for that? I bet nothing that you will notice.

 

[daredevil]

Why use high tech heads with a low tech old school cam.906s will work fine.

 

[IQ52]

What heads are costing $2500?

The difference between the stock 516 (not 216) and the stock 906. These numbers are not from my flowbench but someone elses.

lift..................516..................906

.100...............62....................61
.200.............126..................126
.300.............177..................187
.400.............199..................223
.500.............209..................234
.600.............220..................236

Now from the same bench, a 906 that has a 2.14 intake and TWO HOURS of porting in ONE PORT. That is AT LEAST $100/port, or $800 of porting for just the intakes!

.100.............70
.200...........148
.300...........218
.400...........263
.500...........276
.600...........287
.700...........294

Back to our bench.

Lift.........stock 906...........$500 porting...........OOTB Stealth............OOTB RPM

.100............66......................67........................66............................73
.200..........130....................137.......................142..........................146
.300..........189....................199.......................205..........................209
.400..........222....................239.......................240..........................254
.500..........234....................256.......................255..........................276
.600..........237....................262.......................267..........................287

The ported 906 is $500 for both the intake and exhaust. Then you add head cores, cleaning, bronze guides, valves, springs, retainers, locks, expansion plugs, seals, milling the the surfaces and the valve job.

Given the opportunity, I would like to run factory iron heads every time! But unless you must run iron heads according to the rules, or you just want to use iron heads, or the performance expectations are rather low, the aluminum head is a better dollar value.

 

[RustyRatRod]

Thanks for the 906 and 516 comparison, Jim. That's something I've been wondering about.

 

[IQ52]

Hey Rob, the same guy that did the comparo with the 516 and the 906, spent two hours porting the 516 with the 2.14 intake and got:

.100..........69
.200........145
.300........209
.400........248
.500........264
.600........277

If we can get almost 300 cfm from a J head and a 2.02, I'm sure there is more in there with the 516 and the 2.14

 

[RustyRatRod]

That's encouraging......even though I will be running only the 2.08 along with the 1.74 exhaust valve. I think it will run good on my 383 after seein those numbers.

 

[Meep-Meep]

So my question is this. Who has actual dyno runs with a 906 head and a 452 head? Heads with similar prep to keep things consistent. 516's have pretty much the same port as a 452 so aside from the chamber shape the flow numbers should be similar.

 

[RustyRatRod]

Mopar Muscle did a head shootout a long time ago.

 

[68 Sport Satellite]

Also, I was steering away from stealth heads a year ago when I was starting my build, but did I hear correctly that Stealths OOTB quality is getting better?

 

[IQ52]

Also, I was steering away from stealth heads a year ago when I was starting my build, but did I hear correctly that Stealths OOTB quality is getting better?

Yes it is getting better but you STILL need to check ANY head before you install it.

- - - Updated - - -

So my question is this. Who has actual dyno runs with a 906 head and a 452 head? Heads with similar prep to keep things consistent. 516's have pretty much the same port as a 452 so aside from the chamber shape the flow numbers should be similar.

Such at test would be inconclusive, interesting but inconclusive. The reason being, the same casting number head flows, vary from head to head, port to port. Also the heads vary from casting to casting.

Lift.......915.........915.......906.........902.........902...........452

.100......63...........61.........66...........65..........58.............61
.200....137.........133.......130..........137........127...........130
.300....187.........190.......189..........185........186...........188
.400....216.........215.......222..........206........207...........213
.500....224.........229.......234..........218........220...........227
.600....232.........239.......237..........222........223...........230

The same prep, without flowing the head will vary wildly from port to port, until the porter has gained vast experience. Even then the upper flows need to be compared and balanced.

Then if you take the time to balance the flows from a 906 to a 452 would you really expect to see a power difference. Again, interesting, but why bother.

I can tell you from experience, on March 31, 2006, a 452 head w/290cfm @ .700", on a 451 stroker, with 9.5:1 compression, made 588 lb-ft @ 4600 rpm and 621 hp @ 6100 rpm.

Some of these question may be answered better in the future. We may be able to make the first dyno runs on our own engine dyno this afternoon. The test mule will be just a stock 1971 cast crank 383 with a 4bbl slapped on it. We haven't got everything completely calibrated so who knows how accurate the horsepower ratings will be. But this is just a test to see if the dyno will operate in the automatic mode. It will at least manually load the engine right now.

 

[RustyRatRod]

Here are some flow numbers from Mopar Muscle.

http://www.moparmusclemagazine.com/..._big_block_cylinder_head_testing_flow_charts/

 

[Meep-Meep]

I guess I was after results that MAY show a 906 / 915 head to be better than the flat floor 516 / 452 head. Flow numbers are one thing but installed on an engine going down the track may be a different story - or maybe not. Your dyno run proves that a 452 headed BB will produce some good power - and I know this - but have to wonder why the different port configurations from the factory.

Following the early days of the BB head as I understand / seen it, the intake port floors were flat, then the Max Wedge just got bigger flat floor ports. It wasn't until Harry Weslake's intervention that brought the advanced redesign of the intake port to improve the transition into the bowl area and out of that the 915 heads was born and carried over to the 906. Then for some reason they went back to the flat floor, which may have been an emissions related reason.

As a side note the hemi solves the right turn from port to pocket by radically changing the angle of the intake valve, which is an entirely different approach. But on a wedge, where you are stuck with the valve angles, something else needs to be done if you want to optimize flow. Have you ever seen a 427 high riser head? It's like they raised the roof about 1/2" creating almost a straight shot into the valve pocket. But without such luxuries of radically changing the casting, perhaps working on the turn into the pocket is your only option. Bob Mullen is quoted as saying the 67 440 head can flow within 95% of the Max Wedge head and I believe that's keeping the same 915 port opening.

This is all interesting but I also have to agree why bother sorting out the old iron heads as to which one is better if they all produce similar HP / TQ numbers, however, I'll still run my 915's and 906's. With all the new heads that one can just basically bolt on and get high CFM numbers (with hopefully a redesigned port to promote good velocity) the job is done. I'm just of the opinion that you don't need to take the aftermarket aluminum head to its max regarding valve lift if you only want a nice street cruiser. So what if you are leaving some power on the table. The reward is long life due to a mild cam profile with single springs and a more efficient port that requires LESS cam to get the job done as compared to a restrictive port requiring more cam. The whole purpose of the cam is to make an otherwise restrictive head work better for higher RPM. But if you improve the port design you can get away with less cam and have a broader power range, better idle vacuum all leading to a better overall driving experience.

 

[RustyRatRod]

Well said Meepamous. But you know, it's my opinion that power is left on the table with every build. Look at it like this. Say you built an all out N/A 750 plus HP "street" motor. You couldda put nitrous on it. You couldda put a blower or turbo(s) on it. So really, power is left on the table no matter what you do.

Jim has said all along that ANY of the iron big block heads will support 600 HP.......and I think the flow numbers from the different castings support that. In the end, since they ain't makin anymore big block iron heads I have to ask "what difference does it make?" Like you I don't really give much of a damn about power left on the table either. I say just build what you have and have fun with it.

Hell, races were won and records were broken with every single big block iron casting before the 915 and 906. They WILL perform. It's been proven. Jim has gotten close to 800 HP from 906 iron heads.....maybe he has gotten 800, I don't know. Is it fair to say those who use 906s at a lesser power level are "wasting" 906 heads? I don't think so. But if the 906s can see 800 or close to it, that means the 516s and 452s can see similar. I'm just not that into splittin hairs. I say pick a head and run the sumbitch.

 

[SwedCharger67]

Intake port on modern 4-valve

Maybe it's interesting to see the intake port in my Ducati 916SPS? Talking about straight shot...or deep throat...and yes, no valve springs...

 

[IQ52]

Yes it's very definately true that the aftermarket head with the better low lift flow numbers will help a stock engine by bolting it on without porting.

As to the potential flow of the iron heads, they all have their limitations. The 452 has topped out at around 310 cfm for us at the present time. I doubt that we are going to do much more development on the 452.

The 906 has shown the most potential, as it has gone not quite 350 cfm. The 915 is not as good as the 906 in our tests and seems to be limited to around 330 for us. Can it go more? I think so, but we may not even bother, it's darn expensive testing. Plus no one seems to believe or want to pay for the results.

We put in good but mismatched pieces, that we laying around, when the 500" engine with the 906 heads was making 740 horsepower with 91 octane on the dyno.