[steve25]

In terms of the suggestion in post number 18, Speedmaster does not offer a D port head like his exh is set up for.

While on the subject of those 3 tube headers the op is running , I don’t think I would spend any money on porting aftermarket heads unless I was shortly going to step up to 4 tube headers!

[Chris65LeMans]

Is there an issue fitting 4 tube headers into '65s? I thought I heard that there was.

[tom s]

Chris,sent you a PM.Tom

[Formulajones]

Is that a dome piston I see in there?

Unless you either have iron heads laying around, and don't mind spending some coin at a machine shop going through them, or you're a numbers guy, then I lean much more towards aluminum heads.

I wouldn't squabble over KRE or Edlebrock personally, but if I had to choose I'd probably lean on Edelbrock. I do like the fact that they helicoil the bolt holes.

[steve25]

4 tube headers are never easy on any D port Pontiac, but sometimes heating and bending up a long box wrench works wonders and saves your knuckles and the F word from blasting from your mouth every 20 seconds!

[GTOLou]

Originally Posted by steve25

In terms of the suggestion in post number 18, Speedmaster does not offer a D port head like his exh is set up for.

While on the subject of those 3 tube headers the op is running , I don’t think I would spend any money on porting aftermarket heads unless I was shortly going to step up to 4 tube headers!

Good catch - go to SMH's and round-4tube's. lol.

[Sirrotica]

Originally Posted by PAUL K

If they're in Iowa that is a good place to deal with. I gave up after three clicks on their Website and not finding and address.

Nevada Iowa, right at the bottom of the page.

[JLMounce]

Originally Posted by GTOLou

Good catch - go to SMH's and round-4tube's. lol.

This is something to think about. If you want to think about changing to a 4 tube header, it opens up even further options for heads.

[Jay S]

Sorta surprised knowone else noticed the odd cc’s the mechanic said the 96s heads were? I didn’t do the math, but it would take a lot off the head surface to get the d port 96cc head to 72cc.. I have a set of 96s that are 87cc and been milled .050”. The more you mill the less you gain, I am thinking .150” milling to get to 72 cc. That wouldn’t even seal a head gasket.

Might want to ask again about the intake port also, to get the intake port on an 96 d port to hold 215cc’s you would need to cut clear through the pushrod port and run a offset roller lifter and shaft rockers???? Not to mention hitting water jackets. Something isn’t right???

Lol. If the heads are as described...how much is shipping to Nebraska!

Nice sets of ported D ports are around that are WAY cheaper the an aluminum set. Call one of the head porters like SD performance or one of the other fellas on here and see what they have laying around. Or get some kre D port coming.


Unless of course your 96s are 1968 RA 2s! Which sounds like to me closer matches to the cc’ chamber numbers? Would be crazy not to get them fixed if that is the case. Three tube headers Obviously a d port though.

[68lemans462]

I upgraded to KRE 290 heads years ago. Best thing I ever did to the car, by FAR.

[77 TRASHCAN]

The valves in Kauffman heads are placed in the heads, just like factory heads. Round port Edelbrock are not, I don’t know about the “D” port Edelbocks, though. Speaking of lining up with the piston valve reliefs.

If you do decide on Kauffman heads, I’d buy them from SD Performance, get the exact to version you want. Shipping from them would not be that bad. They are an awesome Pontiac vendor!

You might look for a part number on your piston tops, to be able to find out what the volume of your domes are, for accuracy.

The 3 tube headers do give up some horses, but nothing extreme. If you headers and exhaust system are in good shape, I’dLeave them....for now.

A set of 6X-8’s might be a great thing for this engine, there’s got to be a build able set somewhere close, they are one of the most common Pontiac heads ever made, And no one wants them.

Some of the stuff your mechanic said, don’t set too well with me....

[Will]

I'm with Jay S and 77Trashcan - those numbers don't make sense. The port volume is way too big and the chamber volume is way too small. You sure they're not '68 #16s? Those would be round port exhaust though...

[steve25]

I missed those details about the heads in that one post so let's nail down some facts about D port iron heads.

1) 5 sets out of 8 sets of 1971 casting number 96 heads that have passed thru my hands over the years that have been totally stock, they ( all 5 ) have CCed out on the high side of 98 CCs of chamber volume with stock valves.

This means you would need to mill .156" off of the deck to get them down to 72 CCs which can not be done and still have a head that would hold 16 psi of water pressure, no less holding a head gasket in place to contain cylinder pressure!!

2) your stated Intake port volume of 215 CCs ( 39% increase over stock) can not be achieved either!
It would take extensive and very costly welding repairs to do that.
At 192 CCs of volume if the heads where ported right to maximize flow, you would have grinded thru all 4 port walls in the runner and or valve bowl, period!

Get your cracked disassembled heads back from the shop and do this test out for us if you would?

See if the one of the exh valves will drop down into the intake bowl , all the way down so that it is sitting on top of the valve guide.

If so then you have the start of a heavily ported head.

Please report back with your findings! If

[1968GTO421]

Originally Posted by 77 TRASHCAN

The valves in Kauffman heads are placed in the heads, just like factory heads. Round port Edelbrock are not, I don’t know about the “D” port Edelbocks, though. Speaking of lining up with the piston valve reliefs.

If you do decide on Kauffman heads, I’d buy them from SD Performance, get the exact to version you want. Shipping from them would not be that bad. They are an awesome Pontiac vendor!

You might look for a part number on your piston tops, to be able to find out what the volume of your domes are, for accuracy.

The 3 tube headers do give up some horses, but nothing extreme. If you headers and exhaust system are in good shape, I’dLeave them....for now.

A set of 6X-8’s might be a great thing for this engine, there’s got to be a build able set somewhere close, they are one of the most common Pontiac heads ever made, And no one wants them.

Some of the stuff your mechanic said, don’t set too well with me....

Totally agree on getting KRE's from SD, treated me very well with info.

Yeah that machanic said a few things that caused

Best of luck with this Chris.

[4zpeed]

Originally Posted by Will

I'm with Jay S and 77Trashcan - those numbers don't make sense. The port volume is way too big and the chamber volume is way too small. You sure they're not '68 #16s? Those would be round port exhaust though...

68 #16's are D port heads, I agree though that the current engine builder is offering some major inconsistencies and the OP may need to find new builder.

Edit - Best of luck Chris, you'll get it figured out, plenty of help roun here.



Frank

[steve25]

RA II heads you say?
68 1/2 RAII heads are Round port exh and there is no such thing as a 3 tube header like the op is currently running for those heads.

[Will]

Originally Posted by 4zpeed

68 #16's are D port heads, I agree though that the current engine builder is offering some major inconsistencies and the OP may need to find new builder.

Edit - Best of luck Chris, you'll get it figured out, plenty of help roun here.



Frank

Yeah, that was a major typo. He has #96 heads, which in '68 were round ports. That's what I was referring to but somehow managed to type '16'. Only thing that could explain that chamber volume, but the port volume and headers still don't make sense.

[JLMounce]

Well, let's assume that the mechanic actually measured the CC's correctly and accurately delivered that information. Wouldn't a head milled that far and ported that large by a pretty good indicator of why both of the heads cracked?

On the 3 tube header deal, I get the feeling that the OP really just wants to get this thing back on the road and not spend massive amounts doing it. The 3 tube header will give up some power to a proper 4 tube, but at the end of the day he's probably going to make more power with this deal than he had before, and he's already stated he's just looking to get about the same amount of power back.

No real need I don't think to get rid of those, especially because they do tend to fit and install easier on a D-port than a true 4 tube design.

I like a a mild ported KRE-D with a change to 1.65 rockers on his current cam and a port matched performer rpm. That's just my opinion and how I'd probably do it anyway.

The only issue right now with getting a KRE head, (direct or third party) is that it's spring, everyone is in upgrade and maintenance mode and it may take longer to get than the edelbrock D port.

[ZeGermanHam]

Originally Posted by PAUL K

If they're in Iowa that is a good place to deal with. I gave up after three clicks on their Website and not finding and address.

While their website is indeed comically outdated, poorly designed, and contains typos, the address you couldn't find is listed at the bottom of all pages within their website.

1700 West "F" Avenue, Nevada, IA 50201

[rohrt]

Originally Posted by JLMounce

Well, let's assume that the mechanic actually measured the CC's correctly and accurately delivered that information. Wouldn't a head milled that far and ported that large by a pretty good indicator of why both of the heads cracked?

If we assume that is true we would have to also assume the intake was milled also in order to fit properly, correct?