Messages

1

General Topics / Strange Problem When letting go of accelerator.

« on: October 07, 2008, 10:30:13 PM »

I am facing this intermittent problem with my 318is. When I let go of the accelerator, sometimes, the car won't engage engine brake.

Usually, when I let go of acceleration at high RPM (~2K or more), the fuel economy meter will go to 0 and I can feel the car slowing down due to engine brake.  But sometimes, the meter won't go to 0, instead it remains around around 2-5L/100KM mark and I don't feel any engine brake at all.

It happens more frequently when I turn on the AC. If AC is off, it seems to function normally. Still happens but not as frequent.

When its idling, the RPM will also hover around 1K RPM mark instead of 850-900PRM mark.

The engine also stalled twice today when I let go of the accelerator. The fuel economy mark jumps to around 15L/100KM and the engine just died.

I am wondering whats wrong with the car. Its it due to faulty throttle position sensor (sening I am still engaging accelerator when I am not) or perhaps something is wrong with my ECU?

2

Swaps, Turbos, Buildups / m42 turbo or m50 turbo

« on: September 19, 2008, 03:58:48 AM »

For me, I would pick M42 over M50. The reason is balance. IMHO, the balance in weight, power and handling is more important than just raw power. Afterall, its a daily driver car and not a drag car.

I am someone who prefers a Lotus rather than a Lamborghini. A light car with a small engine than a heavy car with a big engine.

If you are going for 600HP on a M50, you have to consider more than just engine. You have to ensure your differential, transmission etc is able to handle the power as well. There is also ECU, tuning to take care off. Not to mention turbo lag from using a large turbo to generate sufficient boost.

3

Engine + Driveline / Throttle Heater plate delete - Stripped mouunting bolt

« on: September 18, 2008, 03:58:12 AM »

I think the manifold is made of aluminium.

4

Engine + Driveline / Rough Idling

« on: September 17, 2008, 09:45:31 PM »

I am having some idling issues with my 318is. When the engine is idling, its a little on the rough side. There will be some very short pauses or hesitation from time to time.

It doesn't cause the car to stall or anything, just slight rough idling. No problems when revving the engine though.

May I know what could cause the rough idling? Btw, I am using shrick cams. Will those cams result in rough idling for the car?

Thanks!

5

Swaps, Turbos, Buildups / Stroking + FI

« on: September 17, 2008, 09:40:30 PM »

You are planning the same engine as me. I am planning to buy the engine parts from MM as they offer the M47 crank with conrod + pistons and bearings etc. This will result in 8.6 compression.

6

Swaps, Turbos, Buildups / Single Row Chain

« on: September 17, 2008, 02:45:38 AM »

I do know MM has single row chains and sprockets for M42 but no sure how much it cost though. IMHO, single chain will reduce parasitic drag a little and should able to increase HP a little.

7

Swaps, Turbos, Buildups / Power gain on a 16 year old's budget

« on: September 13, 2008, 10:44:36 AM »

OK, here is another good way to improve HP.

Recently, I tried Amsoil Signature 0W30 for my M42. Despite the 30wt oil, it work very well with the engine and its much better than redline 10W40 and Shell 5W40. Then I added the liquimoly ceratec. its a ceramic additive that will coat your cylinder walls etc with micro ceramic to reduce friction. It works great. the engine feels smoother and definitely more lively.

Reducing internal friction is a very good way to get back lost HP and saves petrol at the same time!

8

General Topics / Which Turbo?

« on: September 12, 2008, 09:05:31 AM »

I do agreed that the GT28 will be a better choice compared to the 25.

9

Engine management / spark plugs??? what do you run?

« on: September 12, 2008, 04:24:38 AM »

Btw, I just bought a set of Bosch Platinum Iridium Fusion plugs and I have to say they are even better than the NGKs.

10

Engine management / spark plugs??? what do you run?

« on: September 12, 2008, 04:23:52 AM »

I use Pulstar plugs. They run about $25 for one and let me tell you they are a lifetime investment. Best plug I have ever owned. Check out their website at http://www.pulstarplug.com. You will be impressed. I noticed a difference after the first gas tank. My car just felt snappier. Seriously check out their website.

Oh pulstar. After I checked out their website, I have to say I am rather skeptical about it though. They made a terrible claim on ignition velocity. The speed the flame spreads does not improve power at all! In order to obtain peak combustion pressure, ECUs basically advance the ignition timing. If the flame spreads much faster than normal, the ECU will have to retard the timing to prevent knocking.

11

Swaps, Turbos, Buildups / M42 Oil Feed & Spark Plugs

« on: September 09, 2008, 08:13:35 PM »

For plugs you could try NGK (get heat range 7-8) or Denso (IK22) or even Bosch. Brisk (is also good but is on the expensive side. Another brand thats popular and quite good is volker.

12

Engine + Driveline / How do you throw a rod? Seriously.

« on: September 09, 2008, 12:12:43 AM »

I think the source of the problem is poor maintenance. M42 are well engineered in terms of reliability and if well taken care of, it can run for over 200K miles w/o any issues.

For me, I always use high quality synthetic oil for the engine check the engine for unusual noise. Once, I did not bolt the oil filter housing properly resulting in the engine running almost dry! There is burnt smell and smoke coming out from the bonnet! But the engine still runs well today w/o any problem other than annoying ticking noise from the worn tappets (planing for a rebuild soon so don't bother replacing them).

13

Swaps, Turbos, Buildups / Buildup: My quest for NA 280 hp

« on: September 08, 2008, 09:19:59 AM »

Ok, checked the valves I got last week.

M62 is still the closest match for M42 6 mm stem valve.

N62 valve is even shorter than M62 and there is little gain over M62 valve in any area. It has nicely thinned valve stem however.

5 mm stem S85 and S65 valves seem identical in appearance and measurements. They are somewhat longer than M42 valves and use only one groove collets. I haven't measured their mass but they are quite light indeed. They also have extra cut on valve backside to help flow.

M42B18 (baseline):

33,05 mm
5,95 mm
106,32 mm

M64B44

34,93 mm (+1,88 mm)
5,96 mm
104,12 mm (-2,20 mm)

N62B??

34,88 mm (+1,83 mm)
5,97 / 5,03 mm
100,04 mm (-6,28 mm)

S65/S85

35,47 mm (+2,54 mm)
4,96 mm
111,64 mm (+5,32 mm)



L to R: N62, M62, M42, 2 x S65/S85, S50B30

Clearly S65/S85 valves are superior parts, as they should be. Problems with them I can think of are:

1. Can solid lifters work with 5 mm longer valve stems then original valves?
2. Where can I find valve guides that fit M42 head and have 5 mm stem valves?
3. To get full benefit from lighter weight of intake valves, exhaust valves must be changed too = extra expense
4. New valve spring plates and collets must be purchased = extra expense

I shall study this further.

Nice work you have with the valves!

Regarding the longer valve stems, how about cutting them shorter and then cut grove collars?

14

Swaps, Turbos, Buildups / Help! My Goal for a 2 bar Boost engine

« on: September 07, 2008, 10:23:16 AM »

I am planning to rebuild my M42 motor into something that is able to hold 2 bars of boost.

The first part is to bore up the motor to 2L using 86mm pistons (Read from ludiagsm's thread that wossner pistons are fine for 2 bars of boost).

The 2nd part is to stroke up using the popular 2L diesel crank and well as forged conrods. I am hoping for a compression of perhap 8.5:1 to be able to boost to 2 bar safely.

Now, the main question is what combination of parts can I use to be able to get to 2 bars w/o blowing up the engine? I am leaning towards MM parts but they listed their motor for 250-300HP only. I estimate thats only around 1-1.2 bar of boost. Tried emailing them several times regarding the max boost the parts could take but never did get a reply. I don't live in US thus calling them is quite difficult.

Thanks for the help!

15

Swaps, Turbos, Buildups / Hi there

« on: September 07, 2008, 10:15:48 AM »

you must read all pages behind there is a info

Oh sorry, I miss out your page 2. Found the info on pg2 of the thread. I understand you are using Wossner pistons and Honda conrod (made by Eagle). Am I right?

Btw, I couldn't find any info regarding the crankshaft? Are you using stock crank or another crank?

Thanks!