Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Post Reply
 
LinkBack Thread Tools Display Modes
Old 08-01-2012, 06:51 AM   #1
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,121
3.6 vs 3.8

hi; looking at 3.6 and 3.8 motors and wondering the differences (beisdes the obvious). the bottom end for both has the same part number, so the only difference should be bore and heads. is there much difference in heads - are they interchangeable? also, lne will take a 3.6 to 3.8, and a 3.8 to 4.0. if the cylinders were the same with just different bore, one would think that lne could take the 3.6 to 4.0, unless i am missing something.

any help with understanding would be great, or a point to a place where perhaps i could find this info.

The Radium King is offline   Reply With Quote
Old 08-01-2012, 07:13 AM   #2
Registered User
 
Join Date: May 2008
Location: Toronto
Posts: 2,656
3.8L came out on 997 and I assume a 3.6L from a 996 is a easier swap without having to rewire everything.

Porsche updates the DME every few years as well.
ekam is offline   Reply With Quote
Old 08-01-2012, 09:48 AM   #3
Registered User
 
BYprodriver's Avatar
 
Join Date: Oct 2008
Location: O.C. CA
Posts: 3,709
Garage
Quote:
Originally Posted by The Radium King View Post
hi; looking at 3.6 and 3.8 motors and wondering the differences (beisdes the obvious). the bottom end for both has the same part number, so the only difference should be bore and heads. is there much difference in heads - are they interchangeable? also, lne will take a 3.6 to 3.8, and a 3.8 to 4.0. if the cylinders were the same with just different bore, one would think that lne could take the 3.6 to 4.0, unless i am missing something.

any help with understanding would be great, or a point to a place where perhaps i could find this info.
I believe the cases are basically the same, however some have more "meat" allowing the additional 2mm overbore past the usual 99mm. All LN 99mm bore engines use the OEM 997 3.8 head gasket. I have not built a MKII 3.6 engine yet so I'm not sure about head interchange yet but I would start by comparing part# of heads & valves.
BYprodriver is offline   Reply With Quote
Old 08-01-2012, 11:05 AM   #4
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,121
well, the heads between the 3.6 and 3.8 are different part numbers, but all the ancilliaries (valves, cam housings, etc.) are the same. Most likely the same head with revised combustion chambers for the different bore sizes (like the 3.2/3.4 heads). so *probably* swappable, although i presume benefits would be minimal.

i guess the reason i was asking was to determine why lne doesn't take the 3.6 to 4.0, like they do the 3.8. if fundamentally the same cylinders between the 3.6 and 3.8 then it should be possible. what does one do for a head gasket on a 4 liter car?

The Radium King is offline   Reply With Quote
Post Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 02:13 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page