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Depth of step on 64 150 turbo heads?
Posted by: Mark M ()
Date: November 03, 2017 10:37AM

I'm having a set of 62-63 turbo heads done for my 64 Spyder and need to know the depth of the step on stock 64 150 heads. My 64 heads are already fly cut, so they won't help.

Anyone know the depth, or have a set of 64 turbo heads you could measure for me?

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 03, 2017 11:19AM

All the heads have the same distance from the fin surface to the register as far as I know. Its about .040" more than the machined surface on the jugs. If no one chimes in I can go measure some. Other than the diameter they would all be interchangeable.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 03, 2017 11:22AM

You do know that you will have a higher CR because the early heads have a smaller CC, right?

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 03, 2017 11:43AM

Also, before you have any head work done, make certain the machinist knows you must true the valve cover side of the to the head gasket side of the head BEFORE you do any thing. Don't ask how I know.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

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Re: Depth of step on 64 150 turbo heads?
Posted by: Mark M ()
Date: November 03, 2017 12:43PM

jjohnsonjo Wrote:
-------------------------------------------------------
> Also, before you have any head work done, make
> certain the machinist knows you must true the
> valve cover side of the to the head gasket side of
> the head BEFORE you do any thing. Don't ask how I
> know.


Why is that important?

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: Depth of step on 64 150 turbo heads?
Posted by: 2ragtops ()
Date: November 03, 2017 01:10PM

Mark

Truing the valve cover rails makes sure that the heads are true/flat else when the other side is cut, they will be untrue/caddywhompus [a technical term]

Bob Bauer

Show-Me Corvairs

1966 Monza Convert 140 P/G with A/C, plastic wheel with tele-column am-fm posi-traction
1966 Corsa Convert 180 wood wheel tele-column am-fm sport steering posi-traction
1965 Corsa Coupe Crown V8 mounted mid-body temporarily red lined for repair
House Springs, Missouri

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Re: Depth of step on 64 150 turbo heads?
Posted by: Layton Curtis ()
Date: November 03, 2017 01:23PM

There is a chart in the Tech guide listing the step depth as per the head number. If you will post the head No I'll see if it is listed.

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 03, 2017 01:26PM

[corvaircenter.com]

Mark Ken did a really great job of explaining all this with great photos which now are GONE.

The short answer is the heads warp over time, turbo, possibly worse due to heat. I had my heads opened up to accept light jugs. I could tell by eye they were not true.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

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Re: Depth of step on 64 150 turbo heads?
Posted by: vairmech ()
Date: November 04, 2017 04:32AM

Sorry about the pictures but photobucket wanted money!

It's interesting reading all the responses. The 64 turbo head does not have a "step" as it is an open wedge shaped chamber. The distance the cylinder goes in the head is about .570 and has been mentioned that leaves about .030 clearance of the cylinder machined area to head clearance with a stock steel gasket.

The "step" so commonly referred to is the gasket surface to the squish area on a cylinder head.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Depth of step on 64 150 turbo heads?
Posted by: vairmech ()
Date: November 04, 2017 04:46PM

jjohnsonjo Wrote:
-------------------------------------------------------
> [corvaircenter.com],
> page=1
>
> Mark Ken did a really great job of explaining all
> this with great photos which now are GONE.
>
> The short answer is the heads warp over time,
> turbo, possibly worse due to heat. I had my heads
> opened up to accept light jugs. I could tell by
> eye they were not true.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


I am going to recreate the thread with new picture links. It will have to be a new post but I am not going to re-write the post just copy what I said and put in new picture links. I will title it "How Far Do You Want to Go with Heads" - REpost.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 04, 2017 05:11PM

Thanks Ken, that was a great post. The machinist that screwed up my heads used that to correct them on his dime. He had me standing beside him, before he made any additional cuts. It all worked out in the end. Also, thanks for help me out on the phone on your dime. It was a few years ago no, but I still remember.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

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Re: Depth of step on 64 150 turbo heads?
Posted by: Mark M ()
Date: November 06, 2017 06:07AM

Layton Curtis Wrote:
-------------------------------------------------------
> There is a chart in the Tech guide listing the
> step depth as per the head number. If you will
> post the head No I'll see if it is listed.

Thanks, I only have Volume 3 and it is not listed there.

I have 3 turbo head numbers:

3819904
3886258
3856638

Mark M
Project: 64 Spyder Vert running 80 hp heads and carbs
1st Vair: 65 Corsa 140
St. Louis, MO
Show Me Corvair Club &
CORSA member

"If it's not broken, you're not driving it hard enough"

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Re: Depth of step on 64 150 turbo heads?
Posted by: jjohnsonjo ()
Date: November 06, 2017 07:50AM

Like Ken and I have already said, they are all the same. .5685" to .5715" or .570" +/- .003" from the CC side of the head to the gasket register surface..

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

Image and video hosting by TinyPic

Options: ReplyQuote


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