I guess it depends on the heads! i looked on ebay and saw a pair of 56 pp heads went unsold recently offered at $100. but I also looked in my barn and discovered I have a pair of these heads, I guess I ought to offload them!
Well, this is only my experience but. My current quest to fix up my 283 is the first motor I've ever worked on. After reading a bunch and becoming a little more educated I decided I wanted power pack heads to keep the traditiaonal look, and they will flow better than the stock head I have on there now. The very first swap meet I went to looking for a set of powr pack heads I found a pair for $60 which had already had hardened exhaust valve seats put in em....your experience may vary, but I don't think they are as hard to find as camel hump heads in good condition.
yeah, it's funny! I wonder why the bid went so high? I guess the heads are rare, one year only used on fuelie vettes, but maybe the matching casting dates had something to do with it? they are wierd heads, they have the bosses for bolting accessories on the ends like the 69-newer heads, but no holes drilled. and they're stagger valve cover style.
Is there a mark that will tell you that the heads are power pack ,or is it by the part number or chamber shape?
Wow, mine look a little differnet than that. Mine are a definitive sidways rectangle with a single triangle pointing up out of the middle. The one in squirrel's picture almost looks like a three pointed crown kind of thing. Could be just the angle of the photo and what not...but are there different types of power pack heads? Mine are the 60cc variety.
From the non sharp point on the casting, I would say these are 265 PP heads with the small chambers. 57 PP heads had a distinctively sharp point.
Maybe I am wrong, but I thought the powerpack heads were designed for all around driving. i.e gas mileage etc. Not really performance.
The power pak option was for more performance. Included the heads, four barrel carb and dual exhaust. External id's was the gold colored V on the trunk lid and the dual pipes.
I ran a stock 265 with three speed on the column in my Nomad for many years. Plenty of power, with stock 3.70 rear end, to move that wagon down the road. Got decent mileage too, and I loved the sound of it.
One of the previous messages mentioned a groved rear cam journal. As I remember from my machine shop days in early '60's,it seems like the stock "55 V8 cams (and also the '56 ?) came with a flat machined on the rear journal to deliver oil pressure from the rear main oil hole to a matching hole in the top of the rear cam bearing with every turn of the cam. Seems like if a later cam was used(they fit and work fine)you had to grind a oil carrier notch in the rear cam journal or the lifter oil galleries would not receive any oil. Maybe some other dinosaur can rember this better than me and comment on this potential oil starvation problem if a later cam is to be used.
I used a set of heads on a .040 over '55 265 that I believe were '57 F.I. heads.These heads have the "knob like" filled areas,on each side if the spark plugs,which raise the compresson. The combustion chamber looks the same as the '56 powerpack heads.The ports are also larger than the '56 powerpack's. The "powerpack" heads were identifiable by a pyramid shape sitting on top of a rectangle on the front and back of each head,at the same location you find the "camel humps" on later heads. The '57 F.I. heads had a pair of parallel vertical bars instead of the pyramid shape,sitting on top of the rectangle shape. Also...'55 blocks are useful to people other than restorers. I had this one in a C/A Anglia! They have no cast in il filter receiver and are therefore a little bit lighter.
Right. There was also a pair of heads in that vintage with a single vertical "tower" extending up from the rectangle--they may have been the 270hp dual quad heads. My older brother's stock car buddies used to scour the junkyards for them in the late '60s. As to the question about the different sizes of triangles on 283 heads, I think that's just a matter of what foundry cast them. I've got at least three different size triangles on various years of power pack heads, but they're all the same valve and combustion chamber size.
The last time I inquired about '56 power pack heads. No one could give me exact proof of what they were or looked like. I don't think the Triangle came out till 57 as 56 was the first year. Also some numbers didn't jive. '57 PP heads were alot better from what I understand.
'56 power pack heads were the first to have the triangle symbol on the end of the head, casting number 3725306. The intake ports were enlarged in '57 on all small block heads, even the 2bbl.
The Jalopy Journal
