L36 heads on an L27?

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robroyoldboy
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L36 heads on an L27?

Post by robroyoldboy »

Pure and simple question: will the L36 heads fit on an L27? I see on the Wikipedia site about the 3800 that the L36 heads had larger valves and a higher compression ratio, and I wonder if that would help the L27 make power more like an L36, and if it's possible to use them on the L27. Any knowledge you guys could hit me up with would be appreciated!

Thanks!
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Re: L36 heads on an L27?

Post by 95naSTA »

The heads will bolt up. But, since the S1 and older have a higher deck height, the lower intake manifold valley is larger.. meaning the L36 LIM is too small. And the S1 LIMs have the wrong port spacing.
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Re: L36 heads on an L27?

Post by willwren »

That about sums it up unless you're ready to fabricate your own lower intake manifold.

While related, they really are two different motors.
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Re: L36 heads on an L27?

Post by Jrs3800 »

As well the valve sequence between the 2 engines are different...
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Re: L36 heads on an L27?

Post by robroyoldboy »

Hmmm.... Ok. So basically I can't do it unless I have someone machine me a new lower manifold... So no, I can't make it work. Thanks for the info!
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Re: L36 heads on an L27?

Post by 00Beast »

Well, if you were willing to pay someone for a custom sheet-metal LIM, which would probably cost more than the rest of the engine is worth you could do it, as well as have a custom cam made using the L27 journals, etc but the L36 valve spacing.
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Re: L36 heads on an L27?

Post by 95naSTA »

This was discussed indepth on the old site.

Here are a couple links that were copied and pasted from the old site.
The block comparo pic is actually my 95's.

http://www.oldsconnection.com/forum/vie ... php?t=1318
http://www.fullthrottlev6.com/forums/sh ... ybrid-3800
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