Page 1 of 1
Idiots guide to increasing 0-60 & bhp of a M42 engine...
Posted: Fri Oct 05, 2012 2:05 pm
by kangman
Been through most of the M42 topics and there isnt much on what mods are worth every penny and what mods aren't worth the trouble.
Also can some one clarify whether an m42 has a 'dual mass' flywheel or is it a load of nonsense..
So if you have a tweaked M42 block please post what you did, how much it costs, Pros and cons and would you recommend it.
Also found this link which i thought was very interesting/useful
http://www.r3vlimited.com/Tech/318is.htm
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Fri Oct 05, 2012 8:37 pm
by DHFiS
AFAIK M42 dual mass flywheels were only fitted if the car had air con. They were fitted to avoid the car stalling if the A/C was engaged when the car was at idle.
I recommend the following.
1. Full service
2. Throttle heater delete
3. Refurbed fuel injectors
4. Rolling road remap - I used Circuit Motors at Castle Combe
5. A 4.10 LSD - doesnt change power but makes using the power easier.
Avoid non standard exhausts and intake set ups and accept the fact that a 318iS is not a quick car by today's standards.
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Fri Oct 05, 2012 9:28 pm
by rix313
kangman wrote:
Also can some one clarify whether an m42 has a 'dual mass' flywheel or is it a load of nonsense..
Pretty sure I made it clear what the deal is with dual mass fly wheels in the sticky at the top of this section....
If you want to increase 0-60 fit a 4.25 diff and run 13inch wheels lol.
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Mon Nov 12, 2012 3:08 pm
by kangman
how much is a remap? would it be worth paying that bit more for opposed to getting a chip?
Whats the best diff/lsd for a IS that will rarely see the motorway, but likes to open the taps on empty straights (rolling starts)
COP- is it beneficial to do even tho your ignition system if working fine
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Mon Nov 12, 2012 9:48 pm
by DHFiS
kangman wrote:how much is a remap? would it be worth paying that bit more for opposed to getting a chip?
I paid £350, its expensive but its the best you can get. I tried an off the shelf chip and it didnt increase the power on my car but others have them and their dyno results show good power gains.
Try a chip first and see if you are happy with it.
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Tue Nov 13, 2012 8:01 am
by Brian28
End result of a rolling road remap is a new chip, mapped for your car with everything adjustable tweaked to the best it can be all through the rev range. Probably the single best improvement there is for an M42, and all done without even getting your hands dirty

Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Tue Nov 13, 2012 9:02 am
by Demlotcrew
I honestly dont see how a dual mass fly wheel would stop an engine from stalling when the AC is turned on

Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Fri Nov 16, 2012 8:47 pm
by DHFiS
Demlotcrew wrote:I honestly dont see how a dual mass fly wheel would stop an engine from stalling when the AC is turned on

I'm sure you are correct but why did only cars with AC have them?
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Thu Nov 29, 2012 7:27 am
by joeseth
Hard to explain but more weight on the flywheel will make it less easy to stall. E.g. A skateboard wheel is a lot easier to stop spinning than a car wheel.
On my m42 I've got a lightened flywheel, throttle body delete, k&n panel filter, and a 4.27 diff. Does seem relatively lively. I think the diff makes the most difference. It goes through 1st and 2nd gear really quickly. You can tell its running higher revs on dual carriageways and motorways but doesn't really both me. Plus it's prob only about 500 revs up at any time so not huge. The way it think of it is that it's at a higher rev ready for you to put your foot down

Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Thu Nov 29, 2012 7:54 am
by joeseth
Anyone got any experience with an off the shelf chip? Can't really justify £350 on a rolling road unfortunately. Or anyone have one for sale? The Jim comforting ones sound good from the link above. And how bad can an eBay one be? Worst case you just put the original back in?
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Thu Nov 29, 2012 11:14 pm
by Speedtouch
I can supply one, so long as your original BMW chip number is 1 267 356 378 - you'll need to remove the ECU lid to find out.
You have to be sure to get the correct firmware version (there are 3) else it will either idle like a pig or not even start, and the 318is is notoriously tricky to chip, so beware of just buying some random chip from E-bay.
It adds between 8-12bhp and gives a 7,000 rpm rev limit.
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Thu Nov 29, 2012 11:26 pm
by kangman
how much are your chips? do you have a chip for all 3 versions? are your chips the dogs bollox or do you just get what you paid for?
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Sun Dec 02, 2012 2:05 pm
by Speedtouch
The chips are £35 posted. I can only supply one if your original BMW chip number is 1 267 356 378 - I don't currently have any other versions of 318is chips than this.
The chips work well, as is testified by the Zoners who I have supplied them to.
Please see my Feedback thread to get customer reports on them:
http://www.e30zone.net/modules.php?name ... 46&start=0
Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Wed Dec 19, 2012 12:22 am
by Dave_M3
If you just care about 0-60, remap and a 3.91 diff as you'll hit 60 with the 3.91 in second so no time lost going for third.
Best ways to make a 318is faster in terms of best value for money and relatively cheap mods are a chip, 4.27LSD and an M20 lightened flywheel.
I had about 160bhp in my iS, 4.1 LSD, 6 speed box, lightened flywheel, re-map and usual M42 bits and was as quick as a 330ci

Re: Idiots guide to increasing 0-60 & bhp of a M42 engin
Posted: Wed Dec 19, 2012 8:04 am
by jmc330i
DHFiS wrote:Demlotcrew wrote:I honestly dont see how a dual mass fly wheel would stop an engine from stalling when the AC is turned on

I'm sure you are correct but why did only cars with AC have them?
BMW over engineering possibly. When the AC is switched on, there is a sudden load applied to belts, in most cars I've been in with AC (more modern than E30s) the revs dip a little when the AC kicks in - even my 306 diesel did this.
Whilst I doubt very much the AC kicking in will stall an iS with a single mass flywheel, I expect the dip in revs will be quite noticeable if the AC happens to kick in when the car is at idle - think how many new iS owners in the 90s would be taking the car back to the dealer because of this apparent problem.
As joeseth said, the greater mass of the dual mass flywheel is harder to stop spinning, so would lessen the impact when the AC kicks and make it much less noticeable. I would think it was just BMW trying to make the car as smooth as possible.