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Discussion Starter #1
Has anyone used a chip in thier M5? What about a Remap?

Any results on rolling roads etc?

Is the 3.6 at its limits already?
 

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Cyrus said:
Has anyone used a chip in thier M5? What about a Remap?

Any results on rolling roads etc?

Is the 3.6 at its limits already?
Every production car can be improved by individual remapping, or fine tuning on a resistance dyno. I am planning to do that in the near future, haven't decided yet whether to use the Unichip or the SMT.
:cheers:
 

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Eryk_PL said:
Every production car can be improved by individual remapping, or fine tuning on a resistance dyno. I am planning to do that in the near future, haven't decided yet whether to use the Unichip or the SMT.
:cheers:
I also see that Digi-Tec also do a re-chip although I think that this is for the 3.8 not the 3.6.

As I have only just got my car I am still looking at the possibilites.
 

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it is rather more important to have a 'top tune' S38B38 engine to work as
intended then playing games with 'chips' which -on their own- are not worth the trouble in respect of power-gain, they COULD however mean trouble bcs
of negative side-effects, the S38B38 is pretty much -top-tuned- as it is -
to increase power, which of course is possible up to appr. 400 bhp without
kompressor or turbo, a rather comprehensive engine-tuning is required ££££££- a production car engine is always a compromise, the S38B38 is a
compromized 'motorsport'-engine as it is, to keep it in shape will cost some££££ in any case :byebye:
 

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AndyE said:
Karl, I couldn't agree more.
and so do I.

I think the E34 M5 engine is tuned as much as possible to be practical and to make real and sustained advances in performance would require a great deal of extra ££££ spent on the engine. I think I am right in saying that the 3.8 was the largest 6 cyl engine BMW produced and they stated that this was the limit which was one other reason for making the next, E39 version a V8 (although marketing reasons were also a major factor in this V8 decision as was the cost).

Also the reason why the next M3(M4) will be a V8 as that engine has also reached the limit. (Although again marketing reasons are in play there too)

Now we all know about companies like Emmenegger but the cost is prohibative for most (around £12000 according to BMW CAR Jan 04). Normally more than the munatary value of the car.

After all we are not talking about a Turbo engine which can be chipped relatively easily to provide a large amount of output!

For me I think I will stick to traditional methods although there is little to tune as the exhaust, a normal performance block for naturally aspirated, is already near optimum and the engine well as discussed previously would need serious work to attain any gain in performance.

Simon
 

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Mine seems to be chipped with a 'Starchip'
The recent dyno graph shows 312.4Bhp at the rear wheels though, so I'm assuming it's either a torque increase or a speed Unlimiting chip.

I've had it up to 150Mph but didn't bother going any further cos I thought it was going to limit at 155.

Now Iv'e discovered the original chip in a box in the boot and I need to test it all over again :M5thumbs:

I love my M5 :M5launch:
 

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Ratty said:
Mine seems to be chipped with a 'Starchip'
The recent dyno graph shows 312.4Bhp at the rear wheels though, so I'm assuming it's either a torque increase or a speed Unlimiting chip.

I've had it up to 150Mph but didn't bother going any further cos I thought it was going to limit at 155.

Now Iv'e discovered the original chip in a box in the boot and I need to test it all over again :M5thumbs:

I love my M5 :M5launch:
I would think that 312.4bhp would not be at the wheels, a 3.8 shows around the 290bhp mark at the wheels
:M5thumbs:

It's most probably that this would be a calculated flywheel figure which is about right, assuming yours is a 3.6
 

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Hi Plisken,

Just scrutinised the graph more closely and it actually says

P_wheelREAL_(Hp)#1 for the bhp curve and

P_LCreAL_(lbft)#1 For the torque curve

So I can assume the (unknown) starchip is probably a bhp increase too.

Max torque is 251.4lbft/5724 rpm and
Max Power is 312.7bhp/7050 rpm

I think the last owner must have found the stock chip in the boot, cos he had the dyno check carried out. Didn't tell me about the chip though haha..

I'm of out for a play now... all this talk of M5's lol

Cheers mate ;)
 

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Discussion Starter #12
Guy called ChippedUK says he has a chip for the 3.6 which gives:

342bhp @ 6900 rpm.

What do u reckon?.......More wpoer than a 3.8 from just a chip?.....

How much difference do you think it makes not having any Cats? I have no cats. Do I need a remap do you think?
 

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Discussion Starter #13
Found this info on chipping....anyone had any experience?


http://www.bavariantuning.com/eat_chip_test.php

My only conern is that its from the USA, arent the fuel grades different there to the UK?

Surelt someone here much have some before and after impressions on chipping/remapping?

I might just get rid of the old management and go with the MBE stand alone I have. Much more versatile than the standard stuff. Might just get rid of the MAF and go with a MAP sensor and Throttle Position + Lambda.
 

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HI guys

thought I would put my penny's worth in (for what its worth).

I had the Schrick cams, and the 100cell race kats, and then got it all tuned by a UNICHIP authorised dealer, here in Sweden. The car is running VERY smoothly and I have not experienced any problems yet, I am going to get an adjustable fuel pressure regulator too just to be safe.

I was running a chip before on my previous engine, and apparently because it runs the mixture lean, one of the pistons melted (this happened on a dyno machine!). So I found a nice engine with a lower mileage and swapped it into mine.

I would reccomend something like UNICHIP, as opposed to any type of replacement chip. You can take off the UNICHIP whenever you want by just taking it off and the engine will go back to running of its own ECU.
 

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I agree with a lot of Simonal & the other contributors to this thread.
The S38B38 is touching 90 BHP per litre...
It is an expensive lump to put right when it goes wrong.
To put some perspective on this, the engine was being developed for the BMW M1 nearly 30 yrs ago. The basic engine is the same with many technical refinements along the way. It suffers from heat stress & the material that make up the gaskets & multitude of pipes that hold it all together are not cutting edge.
I may be wrong but there is no knock sensor in the head from memory so poor (low octane) fuels can get the better of it also.

There has been mention of eproms giving you a 14bhp gain.
Effin ell, thats a 4% Increase. You could lose that much & more from running poor fuel or use of a vehicle at higher altitude.
How many of us could feel a 4 % increase. I struggle to detect a 10 %absolute increase in felt power from anything this heavy.

My job has involved the use of engine dynomometers for power, durability & emissions certification.
I am very sceptical of modifications that may not take account of all the variables & they are numerous....!
Some of the aftermarket eproms are worthy of praise but usually require other mechanical modification to take advantage of the mapping.
Alot are not good and promise huge gains.....
They take the engines closer to detonation & load the cooling system with heat spikes which can cause localised hot spots & boiling of coolant causeing softening of heads, blocks & degradation of gaskets.

Result is usually a popped engine. Very sad indeed.

Its a brilliant engine as std. Just enjoy the power & noise of one of the greatest engines in one of the best saloon cars of our time.

Best wishes
Farrell
 
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