E30 engine mods

[V16RAG]

Hi there, I have a 1987 325i convertible, could someone please advise me on the best engine mods. I want to keep the standard lump, but get the most out of it, what is the best induction kit if any. What sensible mods would be advised? What's the most bhp to be expected? Many thanks in advance.

[dave525]

Fit a 2.8 crank. I did this with no other mods and its torquey,pulls well and will still rev to 6500 as I found out by accident when it kicked down on an overtake.Mines a 320 auto cab with a 2.5 engine. I didn't have to touch the pistons,didnt skim the block. Just checked clearances with bluetak and it all works fine.

[Speedtouch]

An '87 325i should have the high compression engine, which if in good condition, should be good for around 175bhp.

A chip is one of the easiest mods to give an extra 8-12bhp, along with improved driveability, and often better fuel economy if driven gently.

I can supply one for a bargain £35 posted, if you take advantage of my January sale.

[Brianmoooore]

First thing you should be doing is getting the engine you have running as it left the factory. This will easily provide your "best bang for your buck", as willnz puts it.
This isn't some old Ford or Vauxhall cr*p, so, even if it has 200,000 miles on it, there shouldn't be any significant basic wear on the engine, as long as it's been serviced reasonably well during its life.
Injectors are the main thing to be in need of a rebuild, so head off to our traders' forum, and check out 'injectortune'. After that, attend to all the induction side air leaks that you don't know about, check that no one's been playing with adjustments that should never be touched, such as throttle stop and AFM bypass, check that the TPS is working as it should, and that the valve clearances are as they should be.
The best 'induction kit' for an E30 is the one that it left the factory with, fitted with a clean and regularly changed OE filter element.