How to check which engine I have?

Post Tue Mar 10, 2015 6:17 pm

The engine in my car was changed in the past at some point, it is supposed to be a 325 engine

- but is there any way for me to physically check it?

I am massively anal about knowing a cars history.

Thanks

Post Tue Mar 10, 2015 6:21 pm

http://www.e30zone.net/e30zonewiki/inde ... of_Engines

Ben

Post Tue Mar 10, 2015 6:33 pm

I just checked the diagram to find out where the engine ID code is on a M20 and it seems that you cant see the number without pulling the engine out?

So I have to pull out the engine to see what it is?

Post Tue Mar 10, 2015 6:36 pm

what shape intake manifold does it have ? a curvy 325i one or a straight sided 320i?

and then how fast is it ? as someone might have swapped them about

Post Tue Mar 10, 2015 6:51 pm

Adil70 wrote:
So I have to pull out the engine to see what it is?

No. Engine type number etc. are visible if you take the air filter/AFM assembly out.

Post Tue Mar 10, 2015 7:00 pm

I found the number, it says ---

BMW 1 278 849

This does not match to any of the numbers in that wiki link?

I found a thread of someone with the same number, trying to find out which engine he had, in 2009.

Any ideas?

Post Tue Mar 10, 2015 7:24 pm

Thats not the engine number. Thats a part number.

You need to find the flat machined face below the inlet manifold, towards the front at the joint with the sump. You'll probably need to scrape it back with a screwdriver.

You are looking for the engine number and another series of numbers like "25 6e1". That stands for 25 = 2.5 / 6 cyl / e1 = early high compression.

Post Tue Mar 10, 2015 7:30 pm

Post a picture up as the inlet manifolds are different

Post Tue Mar 10, 2015 7:35 pm

B7 wrote:Thats not the engine number. Thats a part number.

You need to find the flat machined face below the inlet manifold, towards the front at the joint with the sump. You'll probably need to scrape it back with a screwdriver.

You are looking for the engine number and another series of numbers like "25 6e1". That stands for 25 = 2.5 / 6 cyl / e1 = early high compression.

still cannot find it, argh.

Post Tue Mar 10, 2015 7:36 pm

ross_jsy wrote:Post a picture up as the inlet manifolds are different

Inlet manifolds can be changed. I can remember a few cases over the years of people being sold 'B25s' which were B20 engines with B25 inlets fitted.
Only sure way is to check the engine number.

Post Tue Mar 10, 2015 7:37 pm

http://www.ge39.com/files/zeigeinfo.pdf

You may find this link useful, as it shows you where to find the numbers on each engine and how to decode them.

Post Tue Mar 10, 2015 7:39 pm

jmc330i wrote:
ross_jsy wrote:Post a picture up as the inlet manifolds are different
Inlet manifolds can be changed. I can remember a few cases over the years of people being sold 'B25s' which were B20 engines with B25 inlets fitted.
Only sure way is to check the engine number.

Indeed but it would be a good indication to start with.

B20's are pretty slow, how does it drive?

Post Tue Mar 10, 2015 7:44 pm

Post Tue Mar 10, 2015 8:04 pm

I'd say you're much more likely to find the engine number from underneath. Look for a flat square area where the sump joins the block, as indicated on jmc's image above.

Post Wed Mar 11, 2015 5:06 pm

The head casting number might be the easiest way to tell.

That or 885 casting (last 3 numbers of the head casting number) 2.5 heads have a boss between no1 and no2 exhaust port which is not present on 731 heads.

An 885 head is only used on 2.5 and 2.7 engines if the engine is standard.
E30 2.0 engines had a 731 casting and first gen M20s in 2.0 or 2.3 flavour had 200 castings.

You can see it above the number 2 exhaust port above.