Power pack heads

I found a set of power pack heads casting #3884520.According to the "NUMBERS" their 1966 / 67 283" 195/220hp 60cc power pack heads.I'm thinking about putting them on my 283' with a Comp Cams 262 cam & a small Holley carb.Am I on the right track for a mild street motor with an old school feel?

 

Hard to find better heads for a 283 than the good ol' Power Pack heads.

Some might say to run 305 heads instead, but the vintage look of the old-style 520 castings along with the small high-velocity ports and 1.72"/1.50" valve sizes will do that 283 right.

 

I have 305s on mine, but if ya got the Power Packs....Id run em !

Rat

 

Oh no!! You need big valve heads to make any power along with a mega cam to kill any low speed power.But that's ok because you're running 4.88 gears.

 

That should make a nice little street engine. The only issue is that the stock exhaust valve seats may not hold up with today's gas unless you use an additive. Spending the money to have hardened seats put in is probably a good investment.

 

I'm a cylinder head guy in a race engine shop. I like the #520 power packs with 1.840" intake valves from a 305. That's what I'm usin' in the coupe's 327 with a Duntov 097 cam with 1.6 ratio rocker arms. But the labor doesn't cost me any $.
Those heads will do you just fine and they belong there.
What heads do you have on it now?
Smokey

PM me if I can help more in any way. I type slow we can talk on phone

 

I bought it last year newly rebuilt,it had dbl. humps on it.It's never been fired yet.

 

If your engine has the double hump "fueler" heads on it, I wouldn't change to power packs. Both are great heads, but the 1.94's are better than the PP heads.

 

The dbbl bump heads would be great but they shroud the bore on a 283,.... unless you want to bore .125 over

 

That's what I've been told.Thus the head change.

 

There was an article in CC back in 1984 where they took a 287 ( .030 over 283 ) with Double Hump heads, Performer cam and intake and "downgraded" it to a set of lightly massaged Power Pak heads but kept the same cam, intake, carb and headers. It was in a '66 Malibu with a 4 speed and 3.31 gears. It picked up about 2 MPG and dropped a full second off it's ET's.

A friend has the original PP's on his 250HP 327 '64 Impala with a Summit 1103 cam. Contrary to popular belief it does not "choke off" at 4500, more like 5500. It has a 200-4R and 3.73's behind the mostly original 327, with it's stock hubcaps, whitewalls and fender skirts it has surprised more than a couple 90's "pony car" owners..

 

I started mocking up my 283 with a set of the 461 double hump heads and found a bunch of issues pretty quickly. Combustion chambers overhung the bores, you need more piston dome to make compression and the 1.94 valves are shrouded by the small bore. I ended up switching to a set of the 520 heads. I went with the 1.84 inch intake valves and some bowl work on mine. You're going to have a nice little motor.

 

what design is on the front of head, a pyramid, or square ?

 

Both... a rectangle with a point ,pyramid, on top.

 

Not when the chambers over hang the "little" 283 bore size... That's insane!!!

 

Yep! I think the little 305 4-bbl heads with 57-58cc chambers are way better than the 520's... With the 1.84" intakes valves and the "slightly bigger" intake ports, they will flow some better numbers... I believe that it's also possible to machine the exhaust valve seats to accept the 1.600" diameter valves.... If your "hell bent" on that vintage look, why not screw in some bolts in the accessory(sp) holes and cut them off at the surface... Then grind the ID pads down to look like a vintage cylinder head..

 

I don't care about vintage looks...I just want what works best.

 

I've got a set of the 305 4-bbl heads (1977 vintage) that I'm saving up for a "low buck" 327 build... 307 crank in a 350 block..

 

I've been looking for a set of 4-bbl 305 heads but haven't come across a set(yet).What's the casting number on them?

 

I gotta go in the garage and find out.... I'm heading out to my niece's grad party in a bit.. I'll try and dig those out when I get back. I've been sitting on these heads since the mid '80's and haven't done nothing with them yet...


I'll post some pics of those for ya also..

 

That would be great.
Thanks

 

The best ones are the 416's from the early to mid-80's followed closely by the 601's. They're fairly easy to find, finding a pair that's not cracked is a little harder but they ARE out there.

 

The guy I got the 520's from called & said he found another set.I just went & picked them up.Casting # 3795896 both have a cast date of j73.If I'm correct these are 63's used in the 64' & 65's Correct me if I'm wrong guys.

 

I haven't dug mine out yet... But I'm pretty sure they're 358741 or 462614 castings...

Here's a very cool site to look into for block and cylinder head casting info... You might want to save this one:


http://webpages.charter.net/darrell1/casting_numbers.html

 

Update:Got the 283 w/power pak heads running this week.Made for a great little street motor.I happy with the results.Thanks for all your input guys.

 

In '69 I built a 40-over 283 for my '54 Bel aire. Same PP heads (with new 327 springs) and a 191 hydraulic cam. Some electric drill porting, actually just smoothed out the castings, and it powered that old "covered wagon" along real good! 3 speed stick and 4.11 posi, revs without end!