Nexxussian Erik Johnson Alaska (62 posts) Registered: 04/20/2015 10:32PM Main British Car: 1974, MGB, Citroen Color Rover V8 |
Re: Olds 215 heads
I've heard the Olds engines oil through the pushrod, but I've never actually seen one, together or apart.
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ex-tyke Graham Creswick Chatham, Ontario, Canada (1165 posts) Registered: 10/25/2007 11:17AM Main British Car: 1976 MGB Ford 302 |
Re: Olds 215 heads
Here's a thread on this issue that was on the MGE forum.
[www.mgexp.com] You'll note the schematic that I posted which came from my '61 Olds factory service manual. |
Re: Olds 215 heads
Ok, starting to make sense. The front station pad in the head has a small steel tube that sticks out. I thought that was a roll pin or locating dowel. Now I'm guessing its an oil passage. These Olds engines are so much different than the Buick/Rover 215s. Also noticed I have two different Olds heads. One set is stamped with an S. My buddy says that stands for some rare high compression version. 11 to 1 or something like that.
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ex-tyke Graham Creswick Chatham, Ontario, Canada (1165 posts) Registered: 10/25/2007 11:17AM Main British Car: 1976 MGB Ford 302 |
Re: Olds 215 heads
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6468 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Olds 215 heads
CC the combustion chamber Todd. That will tell you which castings you have. There were three, the common 2bbl, and the scarce 4bb and Jetfire heads. Compression will depend on your pistons but the 2bbl heads have a larger combustion chamber than the other two, which are the same except for some minor casting differences, and are the same chamber size as the Buick heads. Oiling is through the block for all BOP and early R engines. Not sure about the later Rs. Those adjustable rockers are not common and a good find. Use the length pushrods that give you the best geometry.
The Olds intake ports are not quite as good due to the extra head bolt but give slightly better clamping, useful for boosted applications. Jim |
joe_padavano Joseph Padavano Northern Virginia (156 posts) Registered: 02/15/2010 03:49PM Main British Car: 1962 F-85 Deluxe wagon 215 Olds |
Re: Olds 215 heads
"The Olds intake ports are not quite as good due to the extra head bolt but give slightly better clamping, useful for boosted applications. "
Sorry, but that statement makes no sense. Look at the Olds head in the last photo in the first post of this thread. The "extra" bolt holes are the ones closest to the blue tarp. They aren't even close to the intake ports. The common bolt holes are much closer and those are the same on Buford and Rover heads. |
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MGBV8 Carl Floyd Kingsport, TN (4511 posts) Registered: 10/23/2007 11:32PM Main British Car: 1979 MGB Buick 215 |
Re: Olds 215 heads
Sorry, that S means it is for a 8.75:1 155hp version.
Quote: [classicoldsmobile.com] |
BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6468 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Olds 215 heads
Joe, on the Olds heads the extra head bolt gives even clamping around the cylinder, in six places rather than 4. So somewhat better sealing. The use of 5 bolts has been found to cock the head on the head gasket, contributing to leaks and modern practice is to do no more than snug the bottom (5th) bolts down if they are used at all. The 6th bolt required the intake runners to be modified so that the bolts do not break out into the intake runners and the resulting geometry was just not quite as good. Perfectly usable, but for a high performance N/A application the other heads flow a bit better.
IIRC rocker oiling was with the oil coming up through the pedestal around the front head bolt to the rocker shaft. The Olds 2bbl heads can be used, if a flat top piston with no dish is installed at something close to zero deck. You'd have to calculate the CR with that configuration, I can't tell you what it is. What I can tell you is that the 300 heads have large chambers also. I believe they are around 51, 54, I'd have to look. And with those a 350 cid 340 with .050" squish needs a 10cc dish for a 10.6 CR. I think the TA heads are around that volume also though again I'd have to look. If so, it would make an engine built for the 2bbl Olds heads able to accept the 300 or TA heads without changing the pistons. Worth thinking about maybe. Jim Edited 2 time(s). Last edit at 03/28/2016 04:08PM by BlownMGB-V8. |