Heads

[runinapentastar]

How good are 906 heads? Are they a rare find?

[Kevin Garceau]

Nope nothing rare about them. I would guess they were probably the most produced BB head in the late 60s early 70s. But they are a good head.

[runinapentastar]

will it out flow a set of edelbrock heads after a port and polish 3 angle grind and all that junk? weight is not a real factor since it will be in a truck.

[ehostler]

You will have to invest more than $1,200 into a set of 906 heads, before you achieve the performance results of the EB heads out of the box.

Another great thing about the EB heads is that they are 84cc in each chamber. The 906 head can differ by 4cc per chamber (per head) and the nominal values are 88cc - 96cc.

Being aluminum, the EB heads will allow you to run a higher compression with more advance on pump gas.

[dave571]

Modern reserch shows that 906 heads only flow marginally better than any other open chamber BB head.

They are worth something, because of old school thinking that they are THE head to have. Resto guys seem to like them the most.

They seem to be worth 150 to 200 (canadian) each, around here. 100 to 140 usd???

452 heads flow as good, and can be used with unleaded fuel.

[runinapentastar]

thanks for the replys the reason i was asking is cause i found a local guy on ebay selling them for 99. they came out of a 78 w 200 ext cab long bed. they look like they need a rebuild. should i go after them or walk away? by the way i was already looking at a set of roller rockers and springs to combat a roller cam

[Kevin Garceau]

Walk away....the shipping will kill you. They are not that big a deal. I have a set sitting in the shop that have roller springs in them, titanium retainers, new valves, port job professionally done. All the good stuff with about 15 miles on them. For 800 bucks and I will pay shipping.

[runinapentastar]

kevin could you e mail me at tuffenffbullriding@yahoo.com so we can talk more?

[runinapentastar]

hey ehostler can you not put gif images on the signature part?

[ehostler]

I've never tried it. try using the vBcode tags for image insertion.

[ IMG ]image_source[ /IMG ]

just remove the spaces (i had to insert them, so that you could see the tags).

[runinapentastar]

thats what i did and its giving me the links insted

[451Mopar]

runinapentastar, what size cam / engine / RPM / HP are you building?
Are the heads really '906 heads? this was the casting for the 1968 to 1970 Big Block engines (383 and 440 with any carb setup.) If they were on a 1978 engine they were not original to that engine, but just about all the '1967 and newer big block heads flow about the same once they are ported.
The 906 heads are OK upto about 500 HP and a bit over 0.500" valve lift, but they are not really inexpensive to modify to this level. I have seen engine shops charge $1,500 to modify the iron heads. Usually to modify stock iron heads for performance, you would get larger sized high-flow stainless steel valves, open up and port the heads for the larger valves, and install hardened valve seats for unleaded fuel. Add into the cost, performance valve springs, retainers and locks and you start getting into quite a bit of money.

On the other hand, The Edelbrock heads flow better out of the box than ported iron heads.

If the engine is going to be a mild, low RPM R/V engine you won't need such modified heads and mildly modified iron heads may be a better choice, but for low cost performance it is hard to beat the cost/performance of the Edelbrock heads.

With the aluminum heads you will have to spend a bit extra on new "special" head bolts or head studs.

Anyhow, since your in Colorado, I'll be at the Street Machine Shoot out at Bandimere on Sunday, May 4th with my Yellow '71 Charger.

[amxauto-x]

So a 440 out of a '77 Chrysler would have the 906 heads? Or the 452?

[6 packin]

I recently read a issue in a Mag that flowed the Eddy heads and got between 260-275 CFM out of the intake ports. They said it was the most accurate flow bench out to date. I thought Ray B flowed them more than 300 CFM out of the box. I know they have more potential than the old cast iron heads, But leading people to belive that they will make a big high horse race engine for the street car while buying these is wrong. Just wondering what other people thought. I know for a fact that a set was purchased, straped on a hot 440/727 509 Mopar cam, 3500 converter, M1 intake 800 Double pump Holley, the man only gained 1 tenth with them over mildly ported 452 which have the stock valves. He has been racing awhile and knows how to tune it. Although his Compression droped maybe a 1/2 point, it should have seen better ET's. For this reason I will never buy Eddy heads, If I want to drive on the street, iron head it will be. (you would see minimul results on good ported heads on the street) If I want to race I go with Indy, or those New cool lookin NRC Chevy heads

[Kevin Garceau]

check your email.... these heads are ready to go when you are. Hardened seats, stainless valves, roller springs, titanium retainers....ready to go when you are.

[sixpackgut]

6 packin, you say that the man lost 1/2 point of comp. why? were the heads he took off milled to death? you should increase your comp buy just bolting the closed chamber heads on. im confused.

[runinapentastar]

the part number on the heads are 2843906-h he said that where out of a 78 so idont know thats why am asking

[6 packin]

Good question, the 452's were milled but, I need to ask how much. Thinking .040 inch, I not sure why he lost cylinder pressure, but I remeber him saying so. I will find out. A tenth is a tenth, the heads do have more potential for sure.

[amxauto-x]

If the heads were milled, you might consider how much the valves were sunk when they were done. That would change the cc's a lot.

[ehostler]

Do a search and you will find the post that I made with the result from Herb McCandles. All of his testing was done on a dyno. He started with a aet of mildly ported 452 heads and then swapped to the EB heads.

I will take Herb's Dyno runs over second hand information that doesn't have all of the facts.

Also, I never said that these heads are mega power, out of the box. jjust pointing out that in order to get the same level of performance from a 906 or 452 head, you will need to invest just as much if not more money, than the cost of the EB heads.

[ghenderson]

Hi
As for your question on the 906 heads. They are a great head for the street as long as you do not invest to much in them. The Edelbrock heads that I have flow tested are around the 290 range at 600 lift. It is not a problem getting that flow from your 906 with a bunch of work. The problem lies in core shift and thin castings. You will run into problems when getting these flow #s from these heads. Before the Edelbrock heads came out we Bracket guys did not have much choice and believe me I have gone through a ton of these heads over the years racing. They are very thin in the exaust ports and they have a weak point on the parting line just above the head bolts. I have got these heads to flow as much as 320 but that is it. These had paper thin ports and were not a reliable head. Go out and spend the money on the Edelbrock heads and do some minor cleaning and these heads will do you wonders. The other bonus is they finally got it right and pointed the plug in the right direction. The weak point is the valve springs are junk. Terf them right off the bat for a good set.