m3 2.3 conversion to a 2.5?

[koolz]

ok guys if i wanted to have my 2.3 m3 engine upgraded to a 2.5 would all i need is a set of pistons and pins with rings? or do i need any other bits like crank ect? and would all i need to do is get the head bored out to a 2.5? or would i need to have other stuff done to it? and lastly it the job worth it? should i get it done or not? and would it add value to the car or devalue it? as its a e30 m3 softtop.

[M5pilot]

You'll need a crank aswell.

Its a very good upgrade and you should see atleast 250bhp out of the conversion if the compression is nice and high. Get a set of Schrick 284's in there aswell.

Very good torque improvement to be had aswell.

[maxfield]

Yes you will need 95mm pistons and crank (87mm stroke).
I don't think it will add value to the car TBH.
If you really want to go all out.
Pair of 284 cams
Alpha N (Engine managment system)
Carbon airbox.
Should see in excess of 260hp+

[GermanGorilla]

Pending what S14 engine spec you currently have, 48mm TB's, as well as ECU remap, uprated valve springs can be added to the previous posts, and a lot of little other items which will add up very quickly.

2.3 to 2.5, I would budget for about 4-5k with you doing most of the work and fitting, and that could be a little on the low side.

Regards,

The Gorilla.

[herman]

I bought my m3 with the converstion done about 5 ks ago, all schnitzer parts, crank, pistons polished ports head etc. The invoices total £5000.

Just come back from France where I did 2000ks, did'nt miss a beat had her up to 140 and she was still going. Pulls well at low revs, but can rev upto 8500.

I had a 1990 215 bhp and this m3 is a lot more rapid and a better all round car, more drivable for every day use.

Is it worth it? 1986 m3, 5 to 7 grand, plus 5 grand, you won't get your money back. But you could pay 10 grand for a evo 2 and the engine go bump. I looked at it as a m3 with a new engine and running gear, got be to be worth something in the middle. Had the car 9 months and just taxed it and serviced it.

As you say with m3 â€Ëas condition is the main thing.

[eamo]

you will also need to have oil squirters installed along with the new pistons as well - I think most guys go with porsche ones

this is for cooling purposes

[koolz]

shit this is gettin more and more expensive by the minute? i thought it was just a matter of buying pistons and rings along with a crank and gettin the bock rebored and that would be it.
i dont have £5000 to spend at the moment, so i guess im gonna have to give it a miss.
but thanks anyway guys.