Early 461 Heads

[Loren S.]

Re: Early 461 Heads

Check these out, built the day before the heads you are looking at, and they also have the mismatched symbols:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140350260344&viewitem=&sspagename=STRK%3AMEWAX%3AIT

[Tom P.]

Re: Early 461 Heads

Once upon a time, these heads had double humps on each end.
My point? Back in "the day" there were some of us who "made" what we called Power Pack heads from later model double hump heads. The common term applied to the "made" heads were "cheater" heads. By VERY delicately grinding away the double humps and then shaping a pyramid, we could put these later, big valve heads on a 283 block, build it up as much as we could get away with, and run in a stock class. When this was first done to a set of double hump heads, the inspection tech would take a quick look at the end of the heads (on a supposedly stock 283), see the pyramid and pass them as stock. But later, when they begin to figure out what we had been up to, they started taking a much closer look at the symbols on the ends of the heads.
My point? Possibly the heads in question above had the pyramids shaped on just one end, and installed on the block with the pyramids up front. A real good head man at the machine shop could do a real good job of reshaping the double humps into a pyramid. I did these myself waaaaaaaaaaaaaaaaaaaay back when and for some reason hung on to them and eventually they ended up on the SB400 in the 56 with 9 fin valve covers on them (had extra bosses welded, then drilled and tapped for staggered bolt pattern valve covers ).

[Joe L.]

Re: Early 461 Heads

Check these out, built the day before the heads you are looking at, and they also have the mismatched symbols:

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT

Loren-----


These heads look like the "pyramid" has been "reworked", just as Tom describes. Note that the "pyramid" is not centered on the base and the legs of the triangle are at different angles. Also, the "as-cast" area of head proximal to the "pyramid" looks suspiciously "irregular" compared to the natural, adjoining as-cast area.

Note that in Tom's photo of the symbol-modified heads, the as-cast area adjoining the pyramid also appears "irregular".

Another possible tip-off is the fact that screw-in studs have been installed on these heads. That also implies a possible "performance history" for these heads.

[Joe L.]

Re: Early 461 Heads

Once upon a time, these heads had double humps on each end.
My point? Back in "the day" there were some of us who "made" what we called Power Pack heads from later model double hump heads. The common term applied to the "made" heads were "cheater" heads. By VERY delicately grinding away the double humps and then shaping a pyramid, we could put these later, big valve heads on a 283 block, build it up as much as we could get away with, and run in a stock class. When this was first done to a set of double hump heads, the inspection tech would take a quick look at the end of the heads (on a supposedly stock 283), see the pyramid and pass them as stock. But later, when they begin to figure out what we had been up to, they started taking a much closer look at the symbols on the ends of the heads.
My point? Possibly the heads in question above had the pyramids shaped on just one end, and installed on the block with the pyramids up front. A real good head man at the machine shop could do a real good job of reshaping the double humps into a pyramid. I did these myself waaaaaaaaaaaaaaaaaaaay back when and for some reason hung on to them and eventually they ended up on the SB400 in the 56 with 9 fin valve covers on them (had extra bosses welded, then drilled and tapped for staggered bolt pattern valve covers ).

Tom----


Good information; I was totally unaware of this little "trick". However, based on your description, I can see why and how it could be done.

It would be much more difficult, if not impossible, with the later 69+ "double hump" symbol configuration. These have a much "lower profile" and it would require the use of a "foreign substance" to modify the symbol configuration. But, for pre-69 heads there would be plenty of "meat" to enable a reconfiguration without the use of a "foreign substance"..

[Tom L.]

Re: Early 461 Heads

Joe, I'm suprized you didn't know about this "Trick". Racers have been making these kinds of mods to aftermarket heads to make them appear like double hump heads when they were the best that were permitted. Even casting numbers could be "Fixed". Check out the link below:

http://www.castheads.com/disguise_work.php

[William C.]

Re: Early 461 Heads

Racers can be very creative people!

[Roger W.]

Re: Early 461 Heads

Yes they can. Ofeten called "The racer's edge".

[John D.]

Re: Early 461 Heads

Clupper gave the correct answer to the heads Rich is looking for. I had a set of 61-early 62 461 heads for many years. The camel hump had the flat tops.
Same flat camel hump on each end. No bubba work on them.

[Loren S.]

Re: Early 461 Heads

You guys are good - I didn't even notice on the ebay heads the rework job, but looking at it closely now, I can see the outline where the hump used to be, and the pores in the reworked area:

[Joe L.]

Re: Early 461 Heads

You guys are good - I didn't even notice on the ebay heads the rework job, but looking at it closely now, I can see the outline where the hump used to be, and the pores in the reworked area:

Loren-----


I don't think they are "pores". I think it's *****-punching which the "modifier" used to try to, rather ineffectively, simulate the as-cast texture of the surrounding area.

[Tom P.]

Re: Early 461 Heads

Loren-----


I don't think they are "pores". I think it's *****-punching which the "modifier" used to try to, rather ineffectively, simulate the as-cast texture of the surrounding area.

When I did the re-shaping of the double humps into triangles (DANG, I guess it's been ~40yrs ago!!!!!), I tried very hard to completely eradicate all visible evidence of the double humps. Once I finished with the re-shaping, I had the ends of the heads VERY HEAVILY sand blasted as an attempt to restore, or duplicate, the factory cast finish. The result is so-so. To the average Joe, it looks like any other 539 symbol, or the later heads with a pyramid symbol. The BIG difference between 539 heads and later heads with the pyramids is the bolt pattern for the valve covers (staggered on 539s vs straight on later heads). So, as you can see in the pictures above, I fixed that by having the additional bosses welded, drilled and tapped for staggered valve covers. With the 9-fin valve covers in place, to the average Joe, it has a very close appearance to a 283 with a 4520 FI unit. But for the FI gurus, it leaves them scratching their heads! And that was part of the plan.
Furthermore, if you look VERY CLOSELY at my pyramid symbols, you CAN distinguish where the double humps used to be. Also, for those who are quite familiar with the SB400, one of the quickest ways to identify one is by the harmonic balancer (has the big notch halfway around the outer ring). So, I fixed that by having it internally balanced and then used a balancer with a smooth ring (finned 8in balancer from 62-68 327, another little trick).
And ya, the heads have screw-in studs---------------along with a few other mods.
No, it's not the baddest SB400 on the planet, but the BB boys frequently get a little surprise.

[Mike E.]

Re: Early 461 Heads

VERY early 461 heads (beginning of 1961 production) (August/September 1960) had rectangular ID marks, followed by the flat humps which last as late as April 62, but were being phased out by January 62 in favor of the rounded humps.

[Joe L.]

Re: Early 461 Heads

When I did the re-shaping of the double humps into triangles (DANG, I guess it's been ~40yrs ago!!!!!), I tried very hard to completely eradicate all visible evidence of the double humps. Once I finished with the re-shaping, I had the ends of the heads VERY HEAVILY sand blasted as an attempt to restore, or duplicate, the factory cast finish. The result is so-so. To the average Joe, it looks like any other 539 symbol, or the later heads with a pyramid symbol. The BIG difference between 539 heads and later heads with the pyramids is the bolt pattern for the valve covers (staggered on 539s vs straight on later heads). So, as you can see in the pictures above, I fixed that by having the additional bosses welded, drilled and tapped for staggered valve covers. With the 9-fin valve covers in place, to the average Joe, it has a very close appearance to a 283 with a 4520 FI unit. But for the FI gurus, it leaves them scratching their heads! And that was part of the plan.
Furthermore, if you look VERY CLOSELY at my pyramid symbols, you CAN distinguish where the double humps used to be. Also, for those who are quite familiar with the SB400, one of the quickest ways to identify one is by the harmonic balancer (has the big notch halfway around the outer ring). So, I fixed that by having it internally balanced and then used a balancer with a smooth ring (finned 8in balancer from 62-68 327, another little trick).
And ya, the heads have screw-in studs---------------along with a few other mods.
No, it's not the baddest SB400 on the planet, but the BB boys frequently get a little surprise.

Tom----


Yes, one can internal balance a 400 small block reciprocating assembly and use a symmetrical, non-400 balancer. Trying to disguise the THREE freeze plugs on each side of the block is a lot harder, though.

[Tom L.]

Re: Early 461 Heads

Those darn freeze out plugs...Had a few compettitors try this and get caught, silly. In general the smart racers never have problems, they are just a step ahead of the inspectors.

My wife says I was a cheater, I remind her I was never caught!!!

[Tom P.]

Re: Early 461 Heads

Tom----


Yes, one can internal balance a 400 small block reciprocating assembly and use a symmetrical, non-400 balancer. Trying to disguise the THREE freeze plugs on each side of the block is a lot harder, though.

Ummmmmmmmmmmmmmmmm, wellllllllllllllllllll, sort of.
The 70~74 SB400s had three freeze plugs.
Then ~75-76 SB400s had the center freeze plug boss----------------BUT NO FREEZE PLUG!!
And last, ~77-80 SB400s didn't even have the center boss. They were smooth in the center like a 350.
So, with the later SB400 blocks, other than the casting number (and of course, the stamped code on the front of the block------if it hasn't been machined off) how can you EXTERNALLY identify a SB400 block?
Look closely at the sides of the two blocks below.
The top picture is a 350-smaller block. Notice the sides of the block are STRAIGHT.
The 2nd-3rd pictures are a 75 400 block (center boss, no freeze plug). Notice the sides of the block have bulges inline with the cylinders. By adding these bulges, since the 400s have larger bores, there needed to be more space in the water jacket for adequate coolant circulation/cooling and the bulges to the outside of the block permitted the needed interior capacity in the water jacket.
So, you can either visualize these bulges in a 400 block, or, reach down there and feel them!