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How do I go about figuring out if I have a 3.0l or a 2.5l?

I got the car from my uncle. It has a new engine, he says it is a 3.0, but it still has the 2.5's plenum. Is there any sure fire way to figure it out?

Thanks!

Carson

A f a i k,the headcasting depictd the 2.5 or 3.0..just under the pulley..

Well, I just took off the timing belt cover and below the pulley it says 2.5.

I'm a little disappointed because I was told that the 3.0 swap was done, but for the price I payed, it's still definitely worth it.

Thanks for the help!

Carson

Wait a second, you have to look behind the passenger side head. It's tough to see. I don't think it says on the front of the motor. It looks like it has 3.0 head covers.

Greg, where exactly would it say? Is there anything that I have to remove to take a look?

Would a better picture be helpful?

Thanks!

Carson

Carson,

Here's a link on how to check what's on the cylinder head. There's one on the rear of the RH head. It's also on the block behind the starter motor but that's a bit hard to see. It will either show 2.5 or 3.0.

The 3.0L head also has a smaller 2 S mark on it which does look a bit like 2.5

http://www.alfagtv6.com/bb/viewtopic.ph ... highlight=

David

Checked my heads I have in my store today and nothing on the rear..all on the front..
The block,as David says,Is also marked..

The 1x head will have 2s and the other has 2d....left and right..
Also checked a Milano engine from the UK I have..nothing on the rear..

Here's a picture of the casting on the back of the right hand head (next to the firewall). It's not nearly as clear as the one from the link, but its still easy to see. Am I right in assuming that the 2.5 head will not fit on a 3.0 block so this is for sure a 2.5l engine?

I think if you put a 2.5 head on a 3l block you end up getting over 12 to 1 compression. Therefore it is safe to assume that you have a 2.5 engine. (Unless you are running race fuel).

Definitely not race fuel here, so 2.5l it is.

Thanks for the help everyone!

Carson

The blocks have a 2.5 or 3.0 cast into them but it is behind the starter and you will have to remove it to find out. Barring that, you could measure the stroke very easily...

It's a 2.5, that marking behind the head proves it. You can't bolt 3.0 heads onto a 2.5 without a huge amount of work.

The 2.5 is a great motor.

No way really? somewhere else I read the 2.5 exhaust valve/port flows better than 3.0 one do. I have a pair of 2.5 heads but dont have 3.0 ones to compare with. Any idea what the difference in chamber volumes are?
-Tom P.

zambon wrote:I think if you put a 2.5 head on a 3l block you end up getting over 12 to 1 compression. Therefore it is safe to assume that you have a 2.5 engine. (Unless you are running race fuel).

I know it's a bit old topic but it kept me really bothering, to check whether I have stock 2,5 or not. The only thing I found on the right head was "3" "D" and fishlike-symbol all this inside rectangular frame. Same thing for the left head except that "D" was replaced with "S". All markings (4 in total) were found below the pulleys and against the firewall. The marking on third spot, on the block, in the starter motor area (1st cylinder), seems to have been deliberately damaged. By the way engine has stock plenum, and valve covers. With this information on hand can I assume that this is the 3.0 motor?
Thanks,
Pete

Pietere, D and S means Distra and Sinistra, left and right in italian..i'm guessing the 3.0 means the engine size..