New Guy with a 325I bhp question,

[StonyRay]

ok I'm new to the E30 scene always wanted one going to have a look at one today, what kinda bhp does the 325 chuck out, also whats the engine code?

[Speedtouch]

Early high compression one (25 6E) gives 171bhp, later '89-on low compression (25 6K) is a little less at around 160-165bhp. Engine code is M20B25. 25 6E/K is usually printed on the engine number plate next to the radiator, alternatively is on the side of the engine block on a machined flat on the inlet side, to the right of the engine mount (hard to see!)

Welcome to the Zone!

[StonyRay]

Cheers, this'll be a low compression on I think, only £250 no tax n needs a shocker and the battery tray welding for MOT time, have a 1992 Pimera eZX, but its just not right and it looks really poo, needs some mods to make it look the dogs, but an E30 already looks the dogs.

[Speedtouch]

£250 for a 325i has got to be a bargain!

[78dude]

U can go into Carfolio.com and then look up all the datas you need for any car....

[StonyRay]

oh has anyone lowered their E30 60mm? I'm looking at a full shocks n springs set, will this cause scrubbing on 17's? is 35mm a better option?

[Speedtouch]

Yes, you shouldn't lower an E30 more than 35mm-40mm else it upsets the handling and can cause rapid tyre wear. 15"/16" is optimum wheel size for E30s; larger wheels give a hard ride with tramlining.

[StonyRay]

I was thinking of swapping the 17,s for some 16" Lensos

[march109]

Actually the later 325i are also rated at 171bhp but tend to loose power with age as many engines do, the earlier engines tend to stay tight and stay in book bhp. although at a recent rolling road day all the stock engines pre and post facelift made more or less stock power. Goes to show its all down to servicing really.

Lowering by 60mm will not adversley affect handling, using a cheapo shocks and springs even at standard ride height will, H&R do an excelland cup kit which which lowers 60/40 the front lower than the rear is recognised as giving good handling charecteristics. IIRC Alpinas were specced with that stance. The 60mm drop does nothing to adversley affect handling.

The lower you go the more you will affect rear toe and camber, the camber particually will cause tyres to premeturly wear on the inner edges as you cannot adjust the rear toe and camber on an e30 withought rearbeam mods.

15 inch wheels are widely regarded as the best performance option, though many people go as much as 17inch, more is possible, depending on width and offset arch mods may be required.

I personally prefer the handling of my cupkit (60/40) on 15s, but have also used 17s with no major hardship.

[leeparkes]

just had a look at my 88 325 and the code is 25 6E (high comp)
is there any reason why bmw lowered the compression?
ive been told higher comp are better but dont know why!

[StonyRay]

wheres the fuel pump is it an in tank one? or on the side of the tank? are these common to go?

[Speedtouch]

just had a look at my 88 325 and the code is 25 6E (high comp)
is there any reason why bmw lowered the compression?
ive been told higher comp are better but dont know why!

Lucky you! My previous '88 325iSE had the 25 6E and went very nicely indeed. At around 1989, BMW lowered the compression to 'K' (Katalysator) spec to be able to fit dastardly catalytic converters, they did this by fitting different pistons.

High compression is preferable on a normally aspirated engine as it gives a cleaner, crisper burn to the combustion mixture, hence more power and torque and better throttle response and fuel economy.

[gooner1]

wheres the fuel pump is it an in tank one? or on the side of the tank? are these common to go?

Under the back seat Ray, would,nt say it was common for them to go but it happens. What makes you think yours has packed up?

[Blitz]

Yes, you shouldn't lower an E30 more than 35mm-40mm else it upsets the handling and can cause rapid tyre wear. 15"/16" is optimum wheel size for E30s; larger wheels give a hard ride with tramlining.

Completely agree

[Morat]

For handling don't forget rollbars!

Most people judge their handling on roll anyway....and you don't want track stiffness on the road because it costs you grip.

[Flozman]

Lucky you! My previous '88 325iSE had the 25 6E and went very nicely indeed. At around 1989, BMW lowered the compression to 'K' (Katalysator) spec to be able to fit dastardly catalytic converters, they did this by fitting different pistons.

I know that for sure as the later model 325's got owned on the rollers!

[Morat]

But 8.8:1 compression makes for some naughty turbo conversions on the stock internals

[Simon13]

it takes a brave man to turbo you average M20 these days

nothing wrong with toe in on the rear helps on turn in, lots of neg camber isn't great for getting the power down either unless you like snaking up the road or axle tramp!

[fowler]

why do you have to brave si i have the m40 and the m20 turbo's

[bss325i]

My later low comp 325i has made a stock 171bhp on a couple of dynos.

[fowler]

My later low comp 325i has made a stock 171bhp on a couple of dynos.

well barry you engine is tighter than a duck's behind LOL it will make stock power

[StonyRay]

It wont start unless you kick the fueltank. lol, under the rear seats sweet, a quick change then. How much is a clean 325I Manual worth with 160,000 on the clock, she's tight and I can bring her back onto the road for very little.

[Speedtouch]

What spec is it, SE? I bought a black 120,000 mile '88 325iSE 2-door with high compression engine for £700, did some tidying of the bodywork and sold for £1200 but should have held out for £1500+

[StonyRay]

hummm could be a tidy profit and a few months of fun in this, no idea on the spec its a 4door (less desirable?) oh whats the PCD, and reccomended offset?

[Speedtouch]

4-doors are less desirable, though some prefer the proportions. PCD is 100mm, offset 24mm IIRC (of the 7J x 15" BBS).

[pnd]

sO IS This DEFINITIVE THEN? 256E ON THE PLAQUE NEXT TO THE RAD AND ITS HIGH COMP 256k and its not? I thought bmw changed the engines at the end of 1987 but some 88 built cars have 256e on the plaque. is anybody able to clear this up ? I have tried tio read the number on the block but of the three cars here none is visible due to rusting.

[Speedtouch]

It's more definitive to look at the number stamped on the block, just in case the engine has been changed at some point.

Yes, the 25 6E mill was still used on some models until about mid-1988, though RealOEM suggests the changeover point was 09/87
http://www.realoem.com/bmw/showparts.do ... g=11&fg=05

[pnd]

OK so 256e engines are on some facelift cars but of the 3 I have here one is an 86 build 256e1 one an88 build 256e2 and the other a 90 build 256k. This 256e2 is of interest because these cars never seem to go as well as the 256e1 builds which came out on a c,d and early e plates I had always assumed this was because they were lower compression engines like the 1990 cars but now i am being told they too are higher compression engines so whats going on?

[Speedtouch]

Couldn't tell you for sure, I'm sure Ant will be able to say for certain. All I know is my previous '88 325iSE (F-reg) with 25 6E2 (Production 07/88 ) went very well for a 20 year old car, with 0-60 in around 7 sec and an indicated 140 units of speed top

Re: Your block rusting and making the numbers illegible, I had a similar problem and used Jenolite rust remover, followed up by wire brushing, scraping with screwdrivers and wire wool several times over and eventually the numbers become visible again. A skim of grease over the top prevents the problem recurring.

[pnd]

Thanks for that speedtouch but i would like Ant or someone with a similar level of experience to tell me for certain. I currently have an f plate 256e2 code and have had others but all the best 325's i have driven have been c or d platers with the 256e1 code.