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hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 12:56PM

Hi all
Im not having a lot of luck finding the 829 4BBL castings... I have the 2BBL low compression heads and was wondering what I could safely mill them down to? Id like to get as close to 10.25 to 1 as possible but figure that gaining 1.5 points with milling and a shim type gasket probably isnt going to happen.


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: OLds 215 cylinder head .
Posted by: roverman
Date: May 30, 2014 02:52PM

Tony, What piston are you planning to use ? ( ") down from deck ? Gasket thickness ? Willing to deck the block ? I'll check my horde, for that #. Cheers, roverman.


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 04:49PM

I want to use the stock flat top pistons..I could go with a copper shim gasket. I would be willing to deck the block.
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mgb260
Jim Nichols
Sequim,WA
(2465 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: OLds 215 cylinder head .
Posted by: mgb260
Date: May 30, 2014 05:03PM

D&D has a useful chart on head cc's and compression. Olds 2 barrel has 51 cc compared to Buick 300 54 cc. I would take .030 off the heads and deck the block.

[www.aluminumv8.com]


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 05:25PM

Thanks JIm.. The 829 castings are the 43 CC heads.. They show the *749 2BBL castings as being 51CC's..

It could all be done Im just not sure. I just dont want to muck up that $$$ Willpower intake to make it fit on severely shaved heads.. Eventually I might get the stroker engine done and Id hate to have ruined it for fittment on that engine.. Sometimes this stuff is like a circurlar firing squad LOL


Moderator
Curtis Jacobson
Portland Oregon
(4577 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: OLds 215 cylinder head .
Posted by: Moderator
Date: May 30, 2014 05:55PM

I think you should just try to be patient. The heads you want will turn up. These engines have been squirreled away under workbenches and in garden sheds all over the place. Post "wanted" ads. Mention your quest to old-timers at car shows. Call independent machine shops, and ask if they know of someone... They're out there, and when you find them they probably won't even cost much.


quietone
Larry Mimbs
Tennille, Ga.
(93 posts)

Registered:
07/13/2013 04:22PM

Main British Car:
Re: OLds 215 cylinder head .
Posted by: quietone
Date: May 30, 2014 06:02PM

Some deck improvement can be had by lengthening the rods. Find bushings in an appropriate size, bore the rods offset to the top, then install bushings and bore for maximum length. If you use small journal, smallblock Chev rods, they are already longer. I forget the exact amount of length you gain, but it is something like .060 in.



mgb260
Jim Nichols
Sequim,WA
(2465 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: OLds 215 cylinder head .
Posted by: mgb260
Date: May 30, 2014 07:07PM

Larry, .040 longer. Buick/Olds/Rover 5.660,SBC small journal stock length 5.700.


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 07:09PM

Im beating the bushes Curtis.. ;-)


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 07:11PM

I guess this discussion brings up another point.. How well do the production valve seats hold up in the older heads with unleaded fuel?


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6470 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: OLds 215 cylinder head .
Posted by: BlownMGB-V8
Date: May 30, 2014 08:24PM

I never found the seats to be any problem.
I've heard warnings about milling too much off the heads though, and the decks don't have any too much thread for the studs in my opinion. Wasn't there a small chamber Rover head? That'll fit the Olds block without any trouble. Just have to use the Rover rockers and valve covers. Which I realize can be a hardship what with being cast aluminum and all. ;-)

If that doesn't work or you like the Olds look, you can also use the Jetfire heads. They are the same compression as the 4bbl heads and sometimes seem easier to find.

Jim
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hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: May 30, 2014 08:39PM

JIm From what a local Jetfire expert told me the Jetfire also used the *829 casting.. (10.25:1 C.R. for '61-'62 4 bbl auto and manual cars, '63 4 bbl manual cars).

The high compression (10.75) * 534 heads were used on the '63 4-bbl automatics only..


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: OLds 215 cylinder head .
Posted by: Dan Jones
Date: June 01, 2014 08:59PM

> Wasn't there a small chamber Rover head?

Yes but those would put the compression ratio well over 12:1 with the flat top Olds pistons. Standard Rover or Buick 215 heads will still be higher compression than what he's shooting for, though you could use the thick composite head gasket with the standard Buick/Rover heads and maybe be in the ball park (I'd need to run the numbers to verify that).

Dan Jones


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: June 01, 2014 09:04PM

The Rover heads are between 28 and 36CC's... Id have to go with a dished piston since I like to keep quench tight on anything I build.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6470 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: OLds 215 cylinder head .
Posted by: BlownMGB-V8
Date: June 02, 2014 12:50AM

Might want to run some of those numbers to see if there is a better solution. Here's a good shot of various heads:
[www.roversd1.nl]

If you look at the Olds head there is going to be some squish but not a whole lot. Also, see the squarish lugs in the chamber of the 300 Buick heads? I could swear my Jetfire heads had those same lugs. I had a talk with Phil Baker about them and although they are the same CR as the 4bbl heads (within 1/4) I don't think they are the same heads.

I do agree with running dished pistons, but if you do that you might as well pick the heads you like best and have the pistons cut to match.

That photo is not all inclusive either.

Jim



roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: OLds 215 cylinder head .
Posted by: roverman
Date: June 02, 2014 11:43AM

I suspect the "lug",is to start the spark bubble, to a faster burn ? Even though the olds heads reportedly have the valves, closer to center of the bore, hp for comparable build, to the Buick/semi hemi, was near identicle. Perhaps because Buick had better burn/swirl and turbulence properties ? I suppose it's possible, BL could have bought the Olds design-but didn't ? Cheers, roverman.


mgb260
Jim Nichols
Sequim,WA
(2465 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: OLds 215 cylinder head .
Posted by: mgb260
Date: June 02, 2014 05:39PM

The lug or dimple in other heads is just to help hold the head for machining. If you remove it you will have better swirl in the chamber, You would have to mill the heads .030 to compensate. The small chamber Rover heads are probably 3.9 heads milled down also. I could see where excessive milling would thin the head deck and make it more prone to cracking and warping.

[www.v8buick.com]



Edited 1 time(s). Last edit at 06/02/2014 07:48PM by mgb260.


hoffbug
Tony Hoffer
Minnesota
(323 posts)

Registered:
10/15/2007 05:25PM

Main British Car:
Olds 215 EFI

Re: OLds 215 cylinder head .
Posted by: hoffbug
Date: June 02, 2014 08:12PM

Still beating the bushes... Nothing yet


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: OLds 215 cylinder head .
Posted by: roverman
Date: June 04, 2014 11:21AM

Tony, "If" I don't have the heads, I'll sell you new dished/Buick Silvolites, for $100. Cheers, Art.
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