Jump to content

Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse

- - - - -

96 ej25d head question

ej25d 1996 combustion chamber volume official

  • Please log in to reply
1 reply to this topic



    Elite Master of the Subaru

  • Members
  • 3,975 posts
  • Tazewell Virginia

Posted 24 January 2014 - 09:48 PM

Does anyone know the official combustion chamber volume of this head? I've seen either 50cc or 53cc posted on the internet, but nobody has posted anything concrete.

So has anyone out there actually cc'd this head, or know where I can find something from subaru stating the specs for it?

#2 idosubaru


    Elite Master of the Subaru

  • Members
  • 24,101 posts
  • East Coast

Posted 25 January 2014 - 01:20 AM

I think it's 46.2 for EJ25D

50 for Phase II EJ25 (and some turbo EJ25 heads)


1996 EJ25 FSM shows bore and stroke and compression ratio:  99.5 x 79, 9.5


I'm unsure of headgasket thickness, the 610 EJ25 headgasket is 1.52mm thick, but is that a revised thickness or same as the originals?


When back-calculated using 1.52mm headgasket the head volume is 46.2


If you back-calculate using .58 mm headgasket thickness (like Phase II EJ25's) - then that gets you in the 53cc head volume, but i doubt the original EJ25D headgaskets were thin - were they?

Edited by grossgary, 25 January 2014 - 01:27 AM.

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users