318 is mods

All the info you need to race E30's

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irishandy
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Mon Mar 24, 2008 11:15 am

i have my is a while now and am looking to get the most out of it ,any suggestions for what i could do performence wise firstly the clutch has to be replaced :cool:
march109
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Mon Mar 24, 2008 11:29 am

Ususal stuff really if your don't want to strip the engine and rebuild as a stroker.

Chip/remap, exhaust system (manifold is already very good) if any gains ar to be had its in the rest of the syste,. heat shielded intake. Some people also rate removing the heater element from the throttle body some don't. uprated cams.

Lightened flywheel, the 318is one weighs almost twice as much as a 325 item, you can also adjust your cam timing for better performance.
325i Tech 1 Touring, breaking.

2.5 high comp. M20, 3.64 LSD, Fully undersealed, Spax springs & Bilstein shocks, s/s exhaust, Alpina rep wheels and more.
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irishandy
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Mon Mar 24, 2008 7:01 pm

does that meen that the flywheel off a 325 flywheel might fit?
march109
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Mon Mar 24, 2008 7:10 pm

I've heard of people using them yes, don't know if its a direct swap though.
325i Tech 1 Touring, breaking.

2.5 high comp. M20, 3.64 LSD, Fully undersealed, Spax springs & Bilstein shocks, s/s exhaust, Alpina rep wheels and more.
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Weeman
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Tue Mar 25, 2008 10:15 am

agreen
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Tue Mar 25, 2008 10:25 am

most uk m42's wont have the dual mass flywheel , they will have lighter m40 ? one . still needs changing though as its still heavy but lighter than a dual mass .
agreen
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Tue Mar 25, 2008 5:44 pm

. . . The M42 is equipped with tunable cam sprockets from the factory. you can tweak your intake and exhaust cams up to 6 degrees +/- to provide more top end horsepower or more low end torque. . The best setup is to adjust the intake cam to 5 degrees (advanced) and leave the exhaust cam alone. I would recommend having a shop do this work.
maxfield
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Tue Mar 25, 2008 5:49 pm

I see you have learned a lot Arron :)

The M42 is a good engine to tune. Depends on budget.

If you're replacing the clutch, it would be a good idea to go for a lightweight flywheel at the same time.
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agreen
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Tue Mar 25, 2008 6:55 pm

JB lightweight flywheels do not sell a kit for the m42 well they do but not the uk one , the uk m42s mostly have the single mass flywheel and the kits coming from america are desighned for the dual mas flywheels ,so the kit will not fit and has to made up of diffrent parts so to speak before it will fit a standard is with a singl mass flywheel, i belive after speaking to dermot form power for penuts it's something he has done before and knows which bits work well.

if this is a route you are going down just though it might be worth knowing the above .
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Sharabi
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Wed Mar 26, 2008 9:41 am

Thing things have already been covered, but on my track car (jointly owned with mate) we have done the following.

Koni Adjustable suspension
BMC Airbox induction Kit
Chipped
Custom Rear Exhaust
Wilwood BBK

When we RR'd it (prior to putting chip in) it achieved 147 BHP which we were well chuffed with.
We are also looking at getting the Throttle body done on it.

Hope thats of some help to you.
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agreen
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Wed Mar 26, 2008 10:34 am

BMC Airbox induction Kit
If this is the carbon air box induction kit that you speak of then when it was r/r before and after on m car it lost torque and gained no horse power , thats my only dealings with them but that test was onn the same r/r on the same day about 15 mins apart .

If it was r/r before the chip that means that somewhere you have found 11 bhp from the rear box ?

seem a little strange to me , who's rolling road was this on ?
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Sharabi
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Wed Mar 26, 2008 12:43 pm

agreen wrote:
If this is the carbon air box induction kit that you speak of then when it was r/r before and after on m car it lost torque and gained no horse power , thats my only dealings with them but that test was onn the same r/r on the same day about 15 mins apart .

If it was r/r before the chip that means that somewhere you have found 11 bhp from the rear box ?

seem a little strange to me , who's rolling road was this on ?
I think we are probably talking about the same airbox, as the box has a carbon effect on it, protecting the induction cone.

to be fair when we fitted it the car felt to pull better and quicker, but we didn't measure it on a RR.

The rear box was a custom system by Hounslow Tyres (thinking about it i'm just wondering if it was just the rear box lol), he was just told to make an exhaust that would help perfomance, and well i think he's succeeded.

The car was Rolling Roaded at DS Automotives Dyno, Aylesbury
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tim_s
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Wed Mar 26, 2008 1:00 pm

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agreen
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Kedge
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Tue Apr 08, 2008 12:22 pm

agreen wrote:JB lightweight flywheels do not sell a kit for the m42 well they do but not the uk one , the uk m42s mostly have the single mass flywheel and the kits coming from america are desighned for the dual mas flywheels ,so the kit will not fit and has to made up of diffrent parts so to speak before it will fit a standard is with a singl mass flywheel, i belive after speaking to dermot form power for penuts it's something he has done before and knows which bits work well.
JBR flywheels are very expensive one there own, hence why no one does it over here and it took Dermot a fair amount of triel and error until mine fitted.

Mine consists of an M52 Ally flywheel, M52/M42 release bearing, M52 clutch and M20 pressure plate.

The difference is light and day though for throttle response.
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StuMc316is
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Wed Apr 16, 2008 12:04 am

A 325i flywheel is about 19 pounds stock (atleast in the U.S.) and can have material removed to get it to about 13 pounds safely. This is probably the most cost-effective route for getting a lightweight flywheel. You'll also need a 325i 228mm clutch kit and an M20 starter pinion (or a whole M20 starter) and an E21 323i t/o bearing.

In combination with the lighter flywheel, a chip with more useable revs and everything else on the motor sorted, a 4.45 rearend is the real ticket to performance. They're hard to find in the U.S. but may be easier for you guys to find in the UK/Germany. I think there were some touring models that had a 4.45...though you might need to install a limited slip unit.
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Sharabi
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Wed Apr 16, 2008 8:19 am

Sharabi wrote:Thing things have already been covered, but on my track car (jointly owned with mate) we have done the following.

Koni Adjustable suspension
BMC Airbox induction Kit
Chipped
Custom Rear Exhaust
Wilwood BBK

When we RR'd it (prior to putting chip in) it achieved 147 BHP which we were well chuffed with.
We are also looking at getting the Throttle body done on it.

Hope thats of some help to you.
Just an update, now we have also fitted eibach anti-roll bars, now this is exactly a perfomance mod, but it has made a nice difference to the way in which the car handles.

With the flywheel, (i'm not an expert) but from what everyone says good gains can be made by lightening it. its a mod tht i think we will do but only if we need to replace the clutch.
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Weeman
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Wed Apr 16, 2008 8:49 am

The heavy flywheel is what kills the accelleration, almost the same weight and HP as many of its similar aged hot hatches, but over a second slower to 60, Lighter flywheel will improve that no end I've been told. Bought ones bolt straight on, modded 325's need some fettling I think, Personally as a lazy bugger, I'd be tempted to get the cash out for the simple option LOL
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luxy
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Wed Apr 30, 2008 1:29 pm

I've machined off 2.8kg from the outer periphery of my M42 engine reducing the wieght to 6.5kg and you can notice a definate improvement in responsiveness!
Dave_M3
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Wed Apr 30, 2008 1:43 pm

The JE lightweight flywheels appartently make 4th gear feel like 3rd when fitting them, this could be on a car that previously had the dual-mass lump however.

When my clutch gives up, I'll go the lightened 25 'wheel route. Already have the starter ready, lol

I'll be taking out the engine out of my track car after my exams to seam weld the front and do the cage, so I'll do the flywheel at the same time. The current to out bearing started noising a few days before I took it off the road so it seems its only asking for the conversion, lol
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