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How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 04, 2017 07:38PM

Here is the thread I promised with pictures. As you will see I started with 64 110 heads. You will see I have done some port work but not changed all the seats.

This first picture shows you the initial measurements around the gasket surface depth. They are actually pretty close for a used head. You will also see that I used a flat file to smooth any burrs on the fin side. BTW, the .571" numbers will be the depth on all unmolested cylinder heads to the gasket surface. The .652" numbers you see are how far I cut the gasket surface down and are for my checks to make sure I have all the gasket surfaces even.



After looking at the pictures do you see the high and low spots? Yes, I am sure that these heads were level to start with because this is a machined surface.

This next picture shows how much I cut out of the gasket surface on a 110 head. the step is right at .1" and I cut .085 out! leaving a .015" step and it will give me .047" piston to head clearance when I am done.


Next is the cut on the rocker cover gasket area. Pictures speak all the words I could say. I will say this particular set of heads is a little worse than most but not by much. In the last picture you will see on the bottom surface where the cutter NEVER touched but cut all the rest of the way around.





After I have the rocker gasket area squared up I turn the head over and then cut the fin area, I'll have those pics tomorrow.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>


The plane of reference for the rockeer gasket is the fin area after I run the file across the face. Did you notice that even the fin area isn't flat? But, it is relatively uniform to the gasket surface, check my numbers out. Once the rocker gasket is cut it is as parralell as it can be to the fin and head gasket area.

"So do you think the cylinders also move over time"
The block and the cylinders seem to not have a problem with changing dimensions probably because the block doesn't run as hot and the cylinders, well, they are steel and aren't as subject to changes.

With my .047" clearance I am assuming that the pistons are at the top of the cylinders. If I were building a race engine I would check the piston deck height and probably compensate with chamber volume.

As far as the head volume, when I am done I expect to be back near the 50cc volume. The next set of pictures will show you what I am doing to get that.
>>>>>>>>>>>>>>>>>>>>>>

OK, Back to the head mods. If you remember I did some pretty different things to a 110 head that not everyone would consider.

In this first pic you will see the overall head and you can see what has been done so far.


Here is a closer look, yes, it is the Singh groove. I'm pretty sure this will get me back down to a near stock compression. I still have to CC. There is a reason for the little "V" at the deepest part.


Here is the starting place just for comparisons. If you notice the depth numbers are pretty much the same as stock on the cut heads!

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Here is the last installment for head mods. I did this more as an excersise for me to see what I could do to a set of heads and still salvage them? Will I ever do something like this again? Not to 110 heads, Ill add the groove and maybe weld up the squish area next time but there will still be a lot of machining to do to get the compression back down on 110 heads. If you go back past the riff raft to the first set of pictures you will see how far I had to cut the head back and all the other little things I had to do. This is esentially a 95 hp head now. If there is a next time, that is where I will start.

In the first pic for doing the cc check you have to have the head level. At the same time you can see how much farther back I had to cut the step.


n this next pic it is about cc'ing the chamber. First you need a surface to fill to. You can't just fill to the gasket surface because that is to inconsistent. Here you see a round Plexiglas plate with a center hole and 4 bleed holes at the chamber edge. Your right, not all th air will come out the center hole and there will be air bubbles and that makes for inconsistencies. The red around the outside edge is grease that I put on the disc to seal the disc. Seal the disc? Yes, that way the liquid, Wintergreen rubbing alcohol so you can see it and it smells good, doesn't wick up the sides and skew the cc reading.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

In this last pic you will see NO bubbles, green coloring and a full chamber. It even fills the .015" gap in the squish area! Then with the fill hole you can stop very accurately and constantly. I ended up with 46.4 cc volume and that equates out to a 10-1 compression ratio. BUT, keep in mind what has been done. 270 cam, a real squish area and a Singh groove. Even with a 10-1 compression ratio I think this engine will be able to run on regular. Time will tell.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Here is another installment that deals with the issues of the amount I took off the gasket surface. If you remember I took .085" off the gasket surface and then had to take a lot of material out of the combustion chamber. I did take .085 off the length of the pushrod tubes to match what came off the heads. It was easy to do, I just put stop on my lathe and put the tubes in the chuck all the way to the back of the chuck and every one was even. I took off the material on the head side of the tubes.

The issue with the length of the pushrods was brought up earlier also and I am going to attempt to show you here what different length pushrods make on the valve contact pattern, you will be surprised at what you see and sort of corresponds with what I have been saying about pushrod lengths when the subject comes up.

In this picture I tried to capture the stem to rocker contact pattern with a stock length pushrod. I put markers where the actual contact was because I wasn't sure how well it would show up here.

(Sorry, I couldn't find that photo.)
I do remember that the pattern was not ideal but it was not far enough off to warrant changing the pushrods. I also did the same test with a.050" shorter without a major change, yes it was a better pattern but still off.

Now, looking at the contact patters with 2 very different length pushrods there isn't much difference in the contact pattern. In looking at the change and thinking about it the pushrod might have to be .090 shorter or more if the contact pattern would even change enough to make it perfect. My point is, everyone makes a big deal out of having the "correct" stem/rocker contact pattern, but it isn't that big of a deal, is it enough wrong that it really warrants different pushrods for a street engine?. I put the stock pushrods in and I will run this engine that way, or the customer will, and unless he wants some different work done I don't expect him back.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

As I said earlier this was more of an excersise for me to see how far I could go with heads. This has all been done by others before so I am not doing any cutting science project here. Also keep in mind that I wanted to maintain a squish area do adding anything anywhere to move the head AWAY from the piston was out of the question so no extra barrel gaskets or thicker head gaskets. After taking out .085" from the gasket surface the compression ratio was near 13-1! So I started carving on the combustion chamber. Another thing to keep in mind these heads started out as 110 heads. My final compresion checked out at 10-1 but I am pretty sure that can be lived with and still maybe be able to run regular gas becaues of the Singh groove and 270 cam. Time will tell. For those of you that think a 270 cam won't work in an FC, well, We'll see.

To be really honest, I thought about the piston octane cut but I would have had to build a fixture and that just wasn't going to happen right now. You might be able to get 2cc's cut on a piston top. I was surprised at how much I had to take out of the head to get just to where I am and I probably should have gone another 2 cc's to get to 9.5-1 for good measure.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I am resurecting this thread because I have the 63 Rampy done and on the road finally. Just to refresh your memory and you may have looked, this is the engine where I HIGHLY modified 110 heads with the Singh groove. I still ended up with a 10-1 compression ratio. I am running 16 degrees intial advance with a bit of a slow mechanical advance and the normal vacuum advance. There is a 3.55 diff in the truck with a 4 speed. This is a 164 cu. in. engine.

Here is my little rant for the day. Everyone seems to poo-poo a 270 cam for most any reason other than a HP engine and it won't work on the street, especially for an FC. Add to that a 3.55 diff and what everyone says, this isn't supposed to work well.

Well here is a video that I think will prove otherwise! I only have about 20 miles on the engine so far at this point but I have closer to 50 since I have driven it more. I know you won't be able to hear the engine but there is NO spark knock unless I am almost stopped and in 1st gear lugging the engine.


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I'm not sure what gas is in it right now but I know it is at least 6 mos old! I need to put just a little in it and I am going to put Midgrade in it and bump the timing 2 degrees to 18 degrees initial.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

FYI for everyone, I just found out there is REGULAR 87 OCTANE gas in the FC!

So, think about this for a second; 10-1 compressoin ratio, 6 month old 87 OCTANE gas, 270 Isky cam and 3.55 rear gear and ONLY if I lug it real slow is there any spark knock at all. Isn't this everthing that most here say won't work in an FC? If you look at my last video I think I just proved you all wrong.

Would I do this in a PG? I don't think so but it might be interesting just to find out. Is this good for a 145 cu.in engine? I don't think so because 80 hp is just a little anemic to start with.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I put the groove in with a 3/32" mill bit on the mill with the head angled. It takes a bit of set-up.

As far as carbon? If the groove is working like it should I don't think there will be any carbon build up. Everytime the piston comes up on compression it should be shooting a stream of fuel mixture through it. I'm not going to tear this engine apart after a few thousand miles just to find out!
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I can give an update. The owner has the truck and has driven it probably 2-300 miles so far. The only incident that I can report has to be my fault. The engine started running rough at a car show the owner went to with no real noises when the engine ran other than if blew off the vacuum hose on the right choke pull-off. When I pulled the rocker cover off I found what I first though was a broken rocker arm but looking closely the rocker stud broke! Now the question is why?

Upon investigation I found all the push rods in UPSIDE DOWN! I have been building ngines for years and NEVER put the pushrod in upside down, I preach that stuff. I had to change 2 pushrods because one was heated up and galled and the one next to it was broken because the parts went over and broke it. I checked all the other pushrods and they were good. I did change all 6 rocker studs, balls and rocker arms and nuts. Then, just to be sure I went to the other side! Everything was just fine there, all the pushrods were in the correct direction and I put the rocker cover back on.

After putting everything back together the engine fired up and ran just fine after the plug cleared it's self, that only took 30 seconds.

The owner has the truck back and loves it. He is running 87 octane fuel with NO spark knock on 164 +.040 cu. in engine made from the original block. Keep in mind that this is a rampside, 3.55 gear, 10-1 compression, 270 Isky cam and stock exhaust with the lower shrouds on and the heater working.

I would do this to another engine! I just may incorporate the Singh Groove into one of my race engines.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>

As an addition since all the above I have had the chance to take apart an engine that has had the Singh groove. It was one of my race engines and this is the top of the piston. See how clean the groove area is? My supposition is like I said earlier, the fuel mixture will keep things clean from the movement.


Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com



Edited 1 time(s). Last edit at 11/04/2017 07:40PM by vairmech.

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 04, 2017 07:42PM

Just so everyone realizes this is a REPOST so the pictures are back for reference. It may seem to be a little disjointed but keep in mind there were questions asked and I just put the answers down.
Every >>>>>>>>>>>> is a different day and post.

Original Topic

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com



Edited 1 time(s). Last edit at 11/05/2017 06:31PM by MattNall.

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: jjohnsonjo ()
Date: November 05, 2017 05:18AM

Thanks for taking the time.

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: How Far Do You Want to Go With Heads - REpost
Posted by: toms73novass ()
Date: November 05, 2017 06:20AM

Thanks very much Ken!

I am going to attempt to do my heads my self and this will help alot!

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: toms73novass ()
Date: November 05, 2017 09:00AM

Ken, couple additional questions.

If you are redoing a head for a turbo what is your view on the valve seats? Replace with deep?

How about valve guides, steel intake, bronze exhaust. Seals on intake only?

Do you preform guide and seat work after you have done all the gasket/volume machining?

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 05, 2017 10:41AM

toms73novass Wrote:
-------------------------------------------------------
> Ken, couple additional questions.
>
> If you are redoing a head for a turbo what is your
> view on the valve seats? Replace with deep?
>
> How about valve guides, steel intake, bronze
> exhaust. Seals on intake only?
>
> Do you preform guide and seat work after you have
> done all the gasket/volume machining?
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

For a turbo I would definitely do the deep seats.

All guide work needs to be completed before you machine the seat pockets and I only put in bronze guides anymore for any valve or engine.

The only thing that really matters is if you need to do any welding, that needs to be the first thing done. The machining can be done in most any order but I generally do the gasket area last.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: toms73novass ()
Date: November 05, 2017 12:15PM

Thanks for the info,


Do you have a preferred source for deep seats and guides?

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: rick4130 ()
Date: November 05, 2017 04:08PM

Awesome. I love this stuff!!! I appreciate you resizing all those pics! Haha

Rick MacDonald
'63 700 Sedan

rick4130@yahoo.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 05, 2017 05:56PM

toms73novass Wrote:
-------------------------------------------------------
> Thanks for the info,
>
>
> Do you have a preferred source for deep seats and
> guides?
>>>>>>>>>>>>>>>>>>>>>>>>>

LOL, Yeah, me!

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: toms73novass ()
Date: November 06, 2017 03:00AM

Good to know! winking smiley

-Tom


63' Monza Spyder Convertable (in process) MY Build Thread
65' Monza MY Build Thread
73' NovaSS 454 Big block
86' BMW 325es
98' Dodge 2500 12v Cummins Diesel with 1200 lb torque!
98' VW Jetta TDI, for daughter
01' Audi Allroad Stage 3 twin turbo

NFCC
Grand Island, NY

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: corventure Dave ()
Date: November 06, 2017 08:23AM

Great post Ken. This will demonstrate a lot of answers to many head questions.

On the valve cover surface re-machining. I had a long mile head, 200,000+ mile that this surface was severely dipped along the pushrod tube surface for the valve cover. This was at least 3/16 when checked with a straight edge. I actually was able to carefully press it back near flat and level on a hydraulic press without damaging or fracturing the aluminum. A slight milling made it perfect. These engines are remarkable!

Corventure Dave

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: jjohnsonjo ()
Date: November 06, 2017 09:01AM

Never thought about trying it on a head, but I put some YH carb flanges back where they belong using a press.

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: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 17, 2017 07:23AM

I found the valve stem contact pattern pictures I mentioned so I will add that here along with what I said in the old post.

Here is another installment that deals with the issues of the amount I took off the gasket surface. If you remember I took .085" off the gasket surface and then had to take a lot of material out of the combustion chamber. I did take .085 off the length of the pushrod tubes to match what came off the heads. It was easy to do, I just put stop on my lathe and put the tubes in the chuck all the way to the back of the chuck and every one was even. I took off the material on the head side of the tubes.

The issue with the length of the pushrods was brought up earlier also and I am going to attempt to show you here what different length pushrods make on the valve contact pattern, you will be surprised at what you see and sort of corresponds with what I have been saying about pushrod lengths when the subject comes up.

In this picture I tried to capture the stem to rocker contact pattern with a stock length pushrod. I put markers where the actual contact was because I wasn't sure how well it would show up here.


This next picture is the same thing but I use an OTTO Parts pushrod that was AT LEAST .050 shorter than the stock length pushrod. This is on the SAME valve with the SAME rocker arm and the SAME adjustment. Again, I marked the area that was wiped, this area is a little more correct but not by much.


Now, looking at the contact patters with 2 very different length pushrods there isn't much difference in the contact pattern. In looking at the change and thinking about it the pushrod might have to be .090 shorter or more if the contact pattern would even change enough to make it perfect. My point is, everyone makes a big deal out of having the "correct" stem/rocker contact pattern, but it isn't'that big of a deal, is it enough wrong that it really warrants different pushrods for a street engine?. I put the stock pushrods in and I will run this engine that way, or the customer will, and unless he wants some different work done I don't expect him back.


BTW, if you can't tell I love sticky notes!

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: Brizo ()
Date: November 17, 2017 08:45AM

Ken, I cut off strips of carbon copy paper to check rocker to stem contact - work well and gives a very visible impression.

Dan Brizendine,
'64 8door Greenbrier 140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 17, 2017 03:53PM

Carbon paper???? Whats that? I haven't seen any of that stuff in ???????

The post it note paper actually showed very good in person it just didn't show well in the picture.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: chris ()
Date: November 18, 2017 09:16AM

Thanks for the close-ups Ken. I enjoy reading about this stuff.

'65 Monza 4 door
4 speed
110hp
Gardner, KS

Heart of America Corvair Owners Association

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: joelsplace ()
Date: November 18, 2017 09:29AM

Why not weld up the squish so you don't have to cut down the gasket surface? You wouldn't have to cut out so much to get the compression down and it would want stock pushrods. It would keep the charge closer to the plug, give more thermal mass and give more valve to piston clearance.
I can't think of any negatives except the time/cost to do the welding.
If it will run 10:1 on 87 I wonder what you could run with 93?

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 18, 2017 04:27PM

Well, I did think of that but I really couldn't afford all the welding and still have to cut the chambers. I don't have a welder big enough to weld on Corvair heads.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: joelsplace ()
Date: November 19, 2017 01:28AM

Sounds like a good excuse to buy one.

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Re: How Far Do You Want to Go With Heads - REpost
Posted by: vairmech ()
Date: November 19, 2017 05:42AM

Even with a welder, how long does it take to weld up squish area? If you don't put enough material down you need to add weld to fill the voids. Then you need to machine off/smooth the squish area. AND, you still need to remove material from the combustion chamber.
Depending on the effect you are after by doing any welding you are adding labor to the job.

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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