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YOUR RESEARCHIs there a diference between a 3.2 986 and 3.4 996 head?
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Use 2.5 boxster crank inside a 3.8 liter 997 crankcase
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Hell, I have even used a 2.5 Boxster crank inside a 3.8 liter 997 crankcase for a short stroke, Big Bore HI RPM beast.
Is there a diference between a 3.2 986 and 3.4 996 head?
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Leading evidence: 'Use 2.5 boxster crank inside a 3.8 liter 997 crankcase' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use 2.5 boxster crank inside a 3.8 liter 997 crankcase' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
I've read that the differences between the 3.6 and 3.4 996 is the cam carrier location points and the fact that it uses different cams and cam gearing.
Is there a diference between a 3.2 986 and 3.4 996 head?
Use different cams and cam gearing
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Suggestion · Original poster
I've read that the differences between the 3.6 and 3.4 996 is the cam carrier location points and the fact that it uses different cams and cam gearing.
Is there a diference between a 3.2 986 and 3.4 996 head?
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The heads are different part numbers, so chances are no.
I think there are some differences such as AOS holes, etc as well.
edit: Jake gives us the scoop down below!
I'm looking for a 4-6 so that wouldn't matter about the AOS, correct?
I know part numbers will differ due to different chassis codes. I thought the only difference was the stroke and not the bore. Do you not know anyone that has tried to do this?
I've read that the differences between the 3.6 and 3.4 996 is the cam carrier location points and the fact that it uses different cams and cam gearing.
I carry out this type of interchange frequently. I have included an interchange table in my assembly manual that should answer most questions.
Combustion chamber variances of 3cc are the biggest difference in the two heads as long as both are from the same era. Both engines must be "5 chain" to allow this to happen easily. There were no 3 chain 3.4 engines, and all were 5 chain. The 3.2 heads will increase the compression ratio of the engine due to their smaller chambers. The 3.2 and 3.4 share the exact same camshafts and the only difference between the 2 internally is the bore size, CR and intake arrangement.
It is possible to install 3 chain heads on a 5 chain engine and 5 cain heads on a 3 chain engine, according to what the combo is you are shooting for.. Hell, I have even used a 2.5 Boxster crank inside a 3.8 liter 997 crankcase for a short stroke, Big Bore HI RPM beast.
3.6 heads have vane cell adjusters for their vario cam + cam arrangement and NONE of these parts are interchangeable with the earlier engines to include the camshafts.
Its all in the combo.
Heck of a crack in that head. Not sure if that one would be fixable. Looks like it started at the spring seat and missed the spark plug chase then ran to the expansion plug chase. What cylinder is that?
Actually, thats a "good crack" because it doesn't extend to either the intake or exhaust valve spring seat... Those are the easier ones to "fix". We have never had a crack recur after our repairs.
This is a source reference. Confirm exact model applicability in the original material.
