Enhancing performance

[Jona1971]

Hi,

I love my E30 318i pre-facelift with M10B18 engine. If I'd wanted a 325i I'd have bought one.

Mine's only done 100k with FSH and is a minter. I enjoy thrapping it too, I like its light weight and the way the power comes in at 4k rpm. I just wish it had a little more poke.

I've just read the WIKI which says you can change to Motronic 1.3 and fit a performance chip. Any ideas how many bhp I'd get from that?

When the engine breaks I'll probably do the engine swap thing. But right now, what low-ish (few hundred quid) mods can I do to get a bit more out of it? 150bhp is OK.

Any suggestions welcome...

[march109]

If the back seats went down I would suggest folding them down to lower the centre of gravity. As they don't there are only a few performance mods available to you.

First add some racing stripes, ensure they run from the front to the back down the entire length of the car so they drag the whole car through the air. And wax the entire car to make it slide through the air more efficiently.

Next up fit a smaller steering wheel for less rolling resistance. Every kilo of weight you save which spins is worth 4kg of fixed mass!

Then only drive with the windows open to reduce air resistance. Remember the smaller the profile of a shape the less air resistance it encounters, so having no windows (while they are open) means they offer no air resistance!

[jimbom30cab]

Last time I went to the dogs, the winners generally always had a dump just before the race

Top tip...

[Jona1971]

Hilarious, thanks.

Nowt to do then then, the ultimate driving machine?

[pacerpete]

The 318i is a pleasant little tram IF in good fettle do not feel underpowered or horrid, unlike the very underpowered and horrid 316

There is very little you can without spending LOTS of money that will give a noticeable power increase.

What is worth doing is a PROPER engine service by somebody who knows what they are doing. I can guarantee that your ignition timing and your valve clearances will be incorrect , they always are Timing chains and sprockets are a known issue on this engine and most by now will definitely benefit from replacement. Throttle cable adjustment is also worth a check, many old cars do not get full throttle due to to worn linkages/ stretched/ badly adjusted cables. These issues will cause major power / performance / fuel economy losses. Set up properly , these are a great little engine , but alas, there are no free horses from there on

[Jona1971]

Thanks Pacerpete,

I've just done a thorough service (oil, filtersx3, plugs, rotor, distributor, HT leads) with the exception of the Timing and valve clearances. It sounds a bit tickety at idle but I don't know if this is the ICV (new, so I think not), valves (probably) or timing chain (tensioner). So, I'll give it a tune up and see what happens.

Sometimes it just feels like the handbrake is on, if you know what I mean.

It seems like BMW got as much out of it as reasonably possible and I should steer away from silly max-power-type mods. (The WIKI infers its a doddle to get 1360bhp from it...)

Thanks anyway

[cool_ram_in]

Bit tickety at idle? Are u sure it´s not an m40?

Just kiding! U must check timing and valves, it could be loosing some punch thru that...

if they´re properly tuned, they are fine.

Well, i remenber someone talking about using m30 afm and some bigger throttle body but i can´t remember.

well, check the m10 part at fritzbits... http://www.fritzsbits.co.uk/engines/engines.html

bye

[cool_ram_in]

If u had carbs...

http://www.pistonheads.com/GASSING/topi ... 0&t=481031

[Jona1971]

Thanks chaps:

I've done the valves, not tickety anymore.

How to adjust the throttle cable - in our out? Pushing more cable in seems to open the throttle more like WOT? But I would have thought I needed to take up the slack a bit i.e. wind it out? Looking at it its never been moved in 27 years, must need adjusting...

[Jarno]

Hilarious, thanks.

Nowt to do then then, the ultimate driving machine?

I'm building (collecting parts) for a 2 liter M10. E30 318i heads have the big valves and ports, big boys say they're as big as one is going to need.
My aim is to raise compression, add lift to the cam (dbilas 300/300) and make sure every cylinder gets an even mixture and filling (thus, S14 ITB set). Management will be Megasquirt-numbersomething.

It will cost money just like building any other engine.

[Jona1971]

Sounds ace, let us know how you get on and how many bhp you can get.
Good luck

[cool_ram_in]

Jarno and Jona1971, any updates?

[Jona1971]

I just gave mine a good service, adjusted the timing, tappets and throttle cable and it runs sweet as a nut. Can't fault it really. Still could do with more power though...

I've spent the last year doing the other things like brakes and suspension and getting the car as factory as possible.

Still open to ideas for power gains.

[Jarno]

I just gave mine a good service, adjusted the timing, tappets and throttle cable and it runs sweet as a nut. Can't fault it really. Still could do with more power though...

I've spent the last year doing the other things like brakes and suspension and getting the car as factory as possible.

Still open to ideas for power gains.

10:1 comp pistons from an E21 318i, shave the head, higher lift cam, adjustable cam sprocket that you can make from std one so you can time it to zero on even advanced a bit. Bigger injectors, and/or replace the 2,5 bar pressure regulator with OEM 3,0 bar unit.

As for my engine, still in boxes. Parts list with pics is in my topic (Members' E30s).

[Jona1971]

Great, I'll have a look.
What bhp gain do you think you'll get?

[Jarno]

Great, I'll have a look.
What bhp gain do you think you'll get?

My guess is 150 bhp ar the crank. Person who who knows his way around tuned M10s thought my setup might give 150-160.

Limiting factors are valve lift and revs with current part pile. Plus I'd have custom pistons made for higher comp and a lot bigger bore, if I could get rid of my current pistons. Selling them would help the budget.

[motormanmick]

Hello Jona1971, was just killing some time and reading some older posts, with the m10b18, tuned length extractors, get rid of the afm and go maf and chip, you can also go a bigger throttle body, I did mine myself, went plus 3mm, adjustable timing sprocket, get that tuned and that will give you the best bang for your dollar without a rebuild, that will net you about 20 bhp + over stock. All those bits will compliment anything else you may decide to do later to the engine.

[Jona1971]

Hi Mick,
Did you do all that by going to Motronic 1.3 as per the Wiki article?
Cheers,
Jona.

[motormanmick]

Hello Jona1971,
I went with Perfect Power SMT6 piggy back computer and 3 in maf kit, which is now going on my m50 with m52 2.8 crank rebuild, reason I went that way is that it is transferable and programmable via laptop and can accommodate any performance enhancements you do to your engine and when you change engines/cars, just take it off/ refit your afm and your back to std and put it on the next car and away you go.

Perfect Power are now up to SMT8, I've had the SMT6 since about 2006 and works great, there are other similar systems out there. I imagine it would be cheaper to go Motronic 1.3 as per wiki, cheers.

[Jona1971]

Update: I fitted a M20B25 and went to manual too. Its a lot of fun, really enjoying the car now with the extra power