318is m42 bhp?

[Mike-tec]

whats the most power u can safely get out of a 318is without forced induction? iv seen 157bhp out of my friends with an exhaust filter bored out tb chip and remap. is that around the max? cheers.

[GrindCulture]

Metric Mechanics manage to get over 200bhp out of them, if you've got enough cash you could probably build it up to S42 spec which put out somewhere in the region of 280bhp iirc. Stupidly expencive though, MM motors come in at about $8000 and to build anything close to an S42 would probably be over £15k...

[fuzzy]

forced induction would be a better £ per bhp return if you want decent power.

[GrindCulture]

Have a look on http://www.m42club.com for some advice on tuning. There's a few people who have performed low boost "junkyard" turbo conversions that give good power on stock internals. For the big power though you'll have to get custom internals which again, wont be cheap.

[papercutout]

There's been a few supercharged ones on here, see the project section and search 'supercharge m42'.

[Dave_M3]

You don't need all new custom internals for silly power though.
600bhp from turbo'ing is possibly with just uprated pistons and head gaskets.

Supercharging is probably the best way to go if your going to be using the car every day though since the low and midrange torque will be nice and also will be far easier to run than a turbo setup as well as being cheaper to build in the first place.

An S42 is the daddy of the all but 280-300bhp comes at a price with rebuilds after every trip to the shops


Kos managed to get 162 out of his M42 with just remap on super unleaded, skimmed head, custom airbox, heaterplate removed etc.

[projectmick]

Without forced induction you may be able to get towards 200bhp, alot of work though., as I have looked into this myself

For instance:
m47n crank 90mm stroke
bore to 86mm
m3 pistons decked 3.8mm
m3 300cc injectors
uprated cams
itb's
exhaust
live map
panel filter/induction kit

That would be alot of work but should get you towards that figure - would be excellent when you s/c it though!

[pugboy]

IMHO its not worth spending much money tuning an iS when you could buy a 325i. Not only does it have more BHP out of the box, but it makes a better noise.

[Cook318IS]

iv seen 157bhp out of my friends with an exhaust filter bored out tb chip and remap.

ive got a shade under 150 bhp from my standard m42 with a panel filter and pampered engine! getting it dynoed again this coming week to get a 2nd opinion on the figures too. otherwise i personally would go down the m50 road but if you wanted to keep the m42 lump i would supercharge

[fuzzy]

thats exactly my thoughts but people tend to get all upset when you point that out. why spend £££'s tuning something up to have less power than a standard in the range replacement engine?

[GrindCulture]

Not many people seem to be turboing M42s over here, but in the states it's more common than S/Cs. You could probably set up a cheap-ish turbo set up re-using turbos from other cars and fabricating manifolds etc. yourself. Still need standalone though but even that could be tackled yourself. Stock internals should be good for 8-10psi without decompressing? 220bhp could be seen with this sort of set up I would think.

[pugboy]

thats exactly my thoughts but people tend to get all upset when you point that out. why spend £££'s tuning something up to have less power than a standard in the range replacement engine?

I'm allowed to say it as I have an iS.

If you did really want to stick with the original lump then I would think a supercharger would be the way to go.

[pugboy]

ive got a shade under 150 bhp from my standard m42 with a panel filter and pampered engine! getting it dynoed again this coming week to get a 2nd opinion on the figures too. otherwise i personally would go down the m50 road but if you wanted to keep the m42 lump i would supercharge

What BHP was it before? I'm just thinking on those rollers it could have been 149.5bhp to start with....

[Dave_M3]

Especially since the orginal BMW panel filter is the best for flow.

The iS engines can vary a nice bit in bhp when standard it seems though from 136 up to 147 etc.

[Cook318IS]

ive got a shade under 150 bhp from my standard m42 with a panel filter and pampered engine! getting it dynoed again this coming week to get a 2nd opinion on the figures too. otherwise i personally would go down the m50 road but if you wanted to keep the m42 lump i would supercharge

What BHP was it before? I'm just thinking on those rollers it could have been 149.5bhp to start with....

not a clue! was the first time i've ever had a car dynod let alone the iS!

[GrindCulture]

Especially since the original BMW panel filter is the best for flow.

The iS engines can vary a nice bit in bhp when standard it seems though from 136 up to 147 etc.

They do tend to hold power well it seems and a lot of them have loosened up as time goes on. Jons interstellar mileage iS pulled 149bhp on the Rollers at Fritz's at the southwest meet.

[Cook318IS]

Especially since the original BMW panel filter is the best for flow.

The iS engines can vary a nice bit in bhp when standard it seems though from 136 up to 147 etc.

They do tend to hold power well it seems and a lot of them have loosened up as time goes on. Jons interstellar mileage iS pulled 149bhp on the Rollers at Fritz's at the southwest meet.

thats when i got iS dynoed too. IIRC his iS had also done about half my mileage. The well looked after engines can reach 150bhp.

[GrindCulture]

Especially since the original BMW panel filter is the best for flow.

The iS engines can vary a nice bit in bhp when standard it seems though from 136 up to 147 etc.

They do tend to hold power well it seems and a lot of them have loosened up as time goes on. Jons interstellar mileage iS pulled 149bhp on the Rollers at Fritz's at the southwest meet.

thats when i got iS dynoed too. IIRC his iS had also done about half my mileage. The well looked after engines can reach 150bhp.

I remember now, a pretty a good day for power runs across the board

[Bob_S]

m50 all the way

[Jon_Bmw]

One of the runs it peeked at 150 bhp. Despite the car having done mega mileage, the engine is about 80k from an e36. Nice quiet chain too

Still don't think it has 150bhp though. My 160bhp mi16 would destroy it.

[Cook318IS]

Still don't think it has 150bhp though. My 160bhp mi16 would destroy it.
_________________

i have been thinking the same recently. My mate has just bought a 1.8 Audi A3 (about 125 bhp) and it feels nippier than my iS. I know the audi is a "small" car but it has all that unnecessary weight like abs, sound deadening and all the other dead weight stuff!!

[Jon_Bmw]

A3's are also really heavy for what they are. My girlfriend has a great spec(leather, air con, changer, kingfisher blue) 1.6 one and its not that much slower than my iS I don't think.

It'll be interesting to see what power it puts out on a different set of rollers. March109s along with a few others results from the day suprised me somewhat.

[Cook318IS]

mines getting done again this saturday so keep your eyes open for a post or PM or something if your interested?

[Jon_Bmw]

Yeah sorry I didn't make that very clear, I knew you were dynoing yours again at that car meet thing. If you could PM me to the thread details that would be spot on.

[Theo]

149 and 150bhp respectively from cars which left the factory 18 years ago with 136bhp.

How anyone can take figures from that rolling road seriously is beyond me.

[monkey]

when i took mine up to fritzs bits and had it put on the dyno it made 142 ft.lbs of tourque and 166.9 bhp and that was only with an inlarged throttle body and an ecu chip from evolve . was wanting to have it done somewere else to see if or how far out it was but since then i have fitted a pair of schrick cams so wouldn't get a real comparison now anyway . The car dont feel that fast i would think nearer 150bhp .

[rob_htid]

at the end of the day a car on the rollers is a gestimate of power from the fly you could work off wheel bhp but still, different rollers produce different figures the only benifit of a rolling road in my opinion is useing the same rollers before and after mods, even if the figure is out the gain/loss is still to be seen

[monkey]

very true and it was a cold day when i was there guess that will make a bit of differance too

[papercutout]

A3's are also really heavy for what they are. My girlfriend has a great spec(leather, air con, changer, kingfisher blue) 1.6 one and its not that much slower than my iS I don't think.

It'll be interesting to see what power it puts out on a different set of rollers. March109s along with a few others results from the day suprised me somewhat.

Tell me about it, mine is barely quicker than my mates mk4 1.6 16v golf, and I'm SURE the golf is heavier.

Admittedly my engine is fairly shagged and could do with a rebuild....



What I like about the M42 is the revviness - I've driven/drifted a 325 and it felt a bit slow and lazy in comparison (yes, it was faster, but the engine was lazier). I far prefer the revviness of the M42, and thats really the biggest reason I'd consider supercharging mine instead of doing an engine swap.
With a supercharger I'd be around 200bhp, and thats damned good enough for drifting for me! Won't happen for a while though.

[Jon_Bmw]

I think one of the reasons they don't feel that fast is because(they arn't ) of the linear power delivery and distinct lack of torque. My mi16 is a bit similar, but the engine really starts to tug at 5000rpm and it goes on for over another 2000rpm. Turbo cars feel fast as you get a rush of power at a certain RPM, usually 3000 or thereabouts. High CC cars have a lot more torque in the lower rev range and again they feel faster(another way of looking at it is a turbo diesel, they have shit loads of torque and feel rapid, but not that quick as they run out of revs.)

The iS is a bit of an inbetweener, its not really made to rev its tits off and it hasn't really got any significant torque. They are just a smooth linear engine which makes driving them easy.

[monkey]

Jon you are right the 318is needs more torque . i have driven a couple of 205s with mi16s in them and they are quick , i also have citreon zx with a 2.1 multi valve td running at 18psi of boost and that has got torque but still fwd

[ShepsEvo3]

It'll be interesting to see what power it puts out on a different set of rollers. March109s along with a few others results from the day suprised me somewhat.

Jon.. if your passing

I think the best you can get out of a standard M42 with a remap is 152ish BHP. This is what mine churned out after I remapped it myself and even more aggressive mapping didn't give anything more.

My exhaust baffles are now gone and the chain is rattling around 2000-2500 so its not breathing as good and the valve timing is not what it was when I mapped it. A recent run on the dyno confirmed the power had dropped to 144bhp. I checked the mapping and its still maxed so its all down to the exhaust and timing chain for the power loss. Could even have a few tweaked valves since it revs past 7000rpm too

Simons 318is with the E36 bottom end running on the Motronic gave neigh on 160bhp and slightly over with megasquirt. This is obviously due to another 100cc and a nice bottom end mated to the E30 318is head.

I have reasons to disbelieve the 167bhp from Kos's car as he well knows, but with maybe some cam timing tweaking, a decent exhaust and induction kit with suitable remapping, maybe that figure can be had?

[Jon_Bmw]

Paul it has a very restricted inlet track now as the lpg is almost all fitted and the mixer plate probably only has a 1"1/4 diameter which would mean its not fair! I'll be passing back your way in a couple of months in the 205 with one different cam and a chip

[pugboy]

As has been said the RR figures are no good if you dont have a before and after. It sounds to me like the figures some people are quoting from the same RR are about 10% higher.

Jon what gearbox have you got on your Mi16? I started out using the original 1.6 box and it was right laugh. It would pull in 5th like it was in 3rd and would go straight round to the limiter. However I soon blew the diff. I then had the brianwave to put an Mi16 gearbox in thinking that it would be better on the motorway (like thats what it was built for?!) and that ruined it. It took it from being manic and lots of fun to just, well normal.
Anyway I think with a 205 it feels a lot quicker than it really is.

Unfortunately many older cars will be down on power now. My first 205 GTi was a 1.9 and my mates Fiesta Zetec-S could keep up in nearly all situations.

How heavy is an iS? I thought they were around 1100Kg?

[Jon_Bmw]

I think its a BX box, its too long really, but it still revs a lot when doing over 70mph. Its pretty good on track as you can hold the gears slightly longer and are not trying to change gear all the time. The 1.6 box is supposed to be fairly amusing. I think the 8v 1.9 box is the one to go for, but the ratios arn't that different to a BX box.

I admit, it does feel quick as its a tin box with no weight. Ours is stripped out so barely weighs anything. It reeled in a new focus ST in a straight line, I had to let off slightly in 4th or I would have rear ended him slowly at 115 clicks. So perhaps it is quite quick? Its a healthy one in a non rusty shell and with a set of slicks its great on track.