How much power does the average E30 lose

Post Mon Sep 10, 2012 5:34 pm

Wev all pissed ourselves at jeremy james and hamster and their " supercars " which get put on the dyno and have lost like 70 horse power and now have double digits. But I was wondering how much does the average e30 have, having now been around for 20+ years.

Its worrying to think, my 2 litre was ( 129 hp standard?? ) and has a stainless system on it, but i doubt its still in the 120s. Anyone dynoed their standard car before?

Post Mon Sep 10, 2012 5:40 pm

It will be interesting to find out how much my 325i cab has lost.

Post Mon Sep 10, 2012 5:50 pm

there was a thread on this a while back and it's thought that the average M20B25 is putting out around 150bhp.

Stick a stainless exhaust system on it and it may rise to 150.5 bhp, if you are lucky.

Post Mon Sep 10, 2012 5:59 pm

So how much should a new standard m20b25 be whacking out?

I might book a dyno run and see exactly what iv got

Post Mon Sep 10, 2012 6:03 pm

A standard m20b25 from the factory is 170bhp I've been told.

Post Mon Sep 10, 2012 6:05 pm

The average does seem to be around 150hp, however a good service and a bit of the correct repair/maintenance and it will be back to the 165hp mark.

M20 engines don't seem to suffer the severe bore/ring wear that something like an old mazzer will see.

Post Mon Sep 10, 2012 6:17 pm

HairyScreech wrote: however a good service and a bit of the correct repair/maintenance and it will be back to the 165hp mark.

.

so what are the top tips to get one back up ? (obviously without anything majorly expensive)

Post Mon Sep 10, 2012 6:18 pm

Its cam wear that knocks the power down mostly, cost my v8 capri 100bhp!-

Post Mon Sep 10, 2012 6:21 pm

Ouch dough that sounds mad!

Hmmm, means my 320 might only have like 105 brake :O

Post Mon Sep 10, 2012 6:24 pm

Problem is that once the cam wears, the map becomes too rich, for obvious reasons!

Then, people play with the afm mixture settings and its never right again! I had to source an m40 afm with the antitamper in place once i swapped the cam and followers!

Post Mon Sep 10, 2012 6:26 pm

Maybe thats why my engine is running rich as fuck? Because the cam is heavily worn out?

Post Mon Sep 10, 2012 6:28 pm

polsta wrote:
HairyScreech wrote: however a good service and a bit of the correct repair/maintenance and it will be back to the 165hp mark.

.
so what are the top tips to get one back up ? (obviously without anything majorly expensive)

Just a general service, so all filters & oil, coolant flush, new belts, clean out TPS, ICV, throttle body and AFM then finally a proper refurb of the injectors.

Post Mon Sep 10, 2012 6:29 pm

dough wrote:Problem is that once the cam wears, the map becomes too rich, for obvious reasons!

Then, people play with the afm mixture settings and its never right again! I had to source an m40 afm with the antitamper in place once i swapped the cam and followers!

how much is it to replace the cam and followers out of interest ? can you put an uprated cam in without having to change/alter anything else ?

Post Mon Sep 10, 2012 6:31 pm

polsta wrote:
dough wrote:Problem is that once the cam wears, the map becomes too rich, for obvious reasons!

Then, people play with the afm mixture settings and its never right again! I had to source an m40 afm with the antitamper in place once i swapped the cam and followers!
how much is it to replace the cam and followers out of interest ? can you put an uprated cam in without having to change/alter anything else ?

If its a 325i i have followers and a cam

Post Mon Sep 10, 2012 6:40 pm

Don't forget the ignition side of things, a new dizzy rotor and set of NGK plugs.

The last cam I measured had over 200k on it and was ok, however that may not be the case for all engines, some may be dead some may be ok, its easy to check though by measuring the peak of the lobe and just by looking in some cases.

M20s do still suffer cam wear, however not as badly as some due to the rocker/lubrication design, they also have quite mild ramp angles which always helps.

As for putting an uprated cam in with no other mods, if you have lambda control to help the idle/closed loop then you can get away with a mild upgrade but a remap will always help.

Post Mon Sep 10, 2012 7:10 pm

Higher lift/ more aggressive cams wear quicker to, its always worth checking that its getting a good oil supply from the spray bar

Post Mon Sep 10, 2012 7:29 pm

my car drove fine when i had it on the road last sumer after getting it-never had any mechanical problems at all so never looked at anything engine wise, but once its all re built and road ready, then an engine and bay overhaul/freshen up is next in line

Post Mon Sep 10, 2012 8:20 pm

I keep looking at cheap and reliable power gains. My driving test is the 20th and inbetween job interviews and bmx its just something to chip away at. Looked at cams etc but way outta my budget unfortunately.

Post Mon Sep 10, 2012 8:22 pm

verde wrote:I keep looking at cheap and reliable power gains. My driving test is the 20th and inbetween job interviews and bmx its just something to chip away at. Looked at cams etc but way outta my budget unfortunately.

There aren't any for the M20B20 other than swapping it for an M20B25

Post Mon Sep 10, 2012 8:32 pm

Checking the valve clearances and making sure they are within spec will always help to better more efficient running

Post Mon Sep 10, 2012 8:34 pm

^^ that's probably the biggest reason for the loss of power on some.

Post Mon Sep 10, 2012 8:35 pm

Kedge wrote:
verde wrote:I keep looking at cheap and reliable power gains. My driving test is the 20th and inbetween job interviews and bmx its just something to chip away at. Looked at cams etc but way outta my budget unfortunately.
There aren't any for the M20B20 other than swapping it for an M20B25

So iv been told, but if im gunna go down the route of engine swapping id probably just do m52, but im skint just now so il just get the bay looking nice

Post Mon Sep 10, 2012 8:39 pm

Euan, you could always talk to autosprint about a cam regrind.

IIRC they quoted me £140 to have a standard cam reground to 276dg.

Post Mon Sep 10, 2012 8:52 pm

Just stick some nitrous in it, my b25 always loved it, and so will the next!!

Post Mon Sep 10, 2012 9:01 pm

E30BeemerLad wrote:Checking the valve clearances and making sure they are within spec will always help to better more efficient running

Ahh yea, how could I forget that!

Post Mon Sep 10, 2012 9:03 pm

dough wrote:Just stick some nitrous in it, my b25 always loved it, and so will the next!!

Hahaha jesus! Thats not a good idea, that shits reaaal flamable and il probably crash into a tree at some point

Steve that seems not bad, that would give a bit more torque or power?
Also you got any pics of the sport yet?

Post Mon Sep 10, 2012 9:05 pm

Nope, nitrous isnt flammable, only talking 50bhp!

I put 200 through the capri!!

Post Mon Sep 10, 2012 9:10 pm

Wouldnt it explode if i drifted into a tree ( im bout to at some stage its my first car )

Post Mon Sep 10, 2012 9:22 pm

Nah, safe as houses, im a big believer, its very cheap power

Post Mon Sep 10, 2012 9:23 pm

To be honest verde, if you haven't even got your license yet then you should be thankful your first car is a 100+ hp RWD. Any more power than that with zero experience will not have a happy ending.

Certain engines seem to wear more than others. My eyes are bleeding from all the M40/M42 knowledge I've digested this week, and it seems the M40 is highly prone to cam wear, whereas the M20s not so much.

So a full service with rebuilt/new injectors and adjusted valves should see an M20 within 10% of its original figure, if it hasn't missed too many oil changes.

Post Mon Sep 10, 2012 9:28 pm

Yeah your right I think. Il end up dead. Im not a quick driver but its still a dangerous combo especially with our weather. If I survive winter il think about lil things in spring. Then I can go bigger bext year.

I was told the m42s were very strong blocks this really surprises me. Strong block and componants so it passes rhe usual wear onto the cams?

Post Mon Sep 10, 2012 9:36 pm

The top end of an M42 is completely different to an M40. Two cams, for starters. Blocks, however, are pretty much identical.

Post Tue Sep 11, 2012 12:13 am

I would say that injector condition plays a bigger part in power loss than cam wear or valve clearances.

Post Tue Sep 11, 2012 12:17 am

Mine made bang on factory power last time it was dyno'd when standard.

Most M20's i come across are neglected, incorrectly set up and/or full of bodges.

Post Tue Sep 11, 2012 12:36 am

well mine sat for like 2 years so god knows. It seems to run smoother every time its run. Its getting new oil, filters and a waterpump soon. Might open her up check the internals and do the gaskets