[KAMIKADZE]

M5 is not good for turbo , it is high CR bla bla bla

Here are 3 new turboed S38 - I know 3-4 more and this winter 4-5 will be ready - S38 is perfect engine
http://bimmerforums.com/forum/showthread.php?t=415850

 

[farrell]

M5 is not good for turbo , it is high CR bla bla bla

Here are 3 new turboed S38 - I know 3-4 more and this winter 4-5 will be ready - S38 is perfect engine
http://bimmerforums.com/forum/showthread.php?t=415850

Hmm
Its all so easy.
Makes you wonder why BMW did not think of it...!
Oh yes, They had to think about durability, emissions, passby noise & serviceability.

Any ar*e can bolt on a Turbo & aftermarket engine managment kit.
making it last longer than an oil service is another issue altogether.

Nobody said it could not be done.... its how long it lasts that was the issue at hand.

Farrell

 

[Jahangeer]

Kamikadze

I understand why some people go for the extra power that the Darkside offers but...

a/BMW tested the prototype cars with a 60,000mile run after they came off the factory floor. Can you honestly say one of the turbo charged cars could do this non-stop?

b/How often are these cars used for everyday service, and how many are trailer queens?

c/How often do these turbo charged cars spend in the garage being fixed for blown gaskets etc etc?


Not having a go at you for believing in getting more power - but as Farrell said its got its downsides.

 

[BURTON]

But I doubt they are for anything but show and some go! Never would I expect these cars to be driven daily. With something of that much power that is aftermarket it would be crazy to drive it always.

I know someone who is Turboing his E30 M3 and keeping the 4cyl as the 6 cyl weigh the front down to much.

 

[redl1nerpm]

But I doubt they are for anything but show and some go! Never would I expect these cars to be driven daily. With something of that much power that is aftermarket it would be crazy to drive it always.

I know someone who is Turboing his E30 M3 and keeping the 4cyl as the 6 cyl weigh the front down to much.

yea i dont think those guys drive the cars everday. The point is just for them to say hey, look how much power we got out of these bmw engines. Then they'll get all kinds of bmw owners that want to get more power, coming to them asking them how and paying them to do the work. Thats just what shops do to get more interest and business.

 

[WylM5]

Hmm
Its all so easy.
Makes you wonder why BMW did not think of it...!
Oh yes, They had to think about durability, emissions, passby noise & serviceability.

Any ar*e can bolt on a Turbo & aftermarket engine managment kit.
making it last longer than an oil service is another issue altogether.

Nobody said it could not be done.... its how long it lasts that was the issue at hand.

Farrell

Actually Alpina went the turbo charger route and did a bi-turbo set up on our E34 (albiet not on the S38 engine) to make their version of an M5. Is it more reliable than our S38? That I have no idea on but it does perform as well or better than the S38 engine 3.6 or 3.8 version.

 

[IvanDias]

Actually Alpina went the turbo charger route and did a bi-turbo set up on our E34 (albiet not on the S38 engine) to make their version of an M5. Is it more reliable than our S38? That I have no idea on but it does perform as well or better than the S38 engine 3.6 or 3.8 version.


M5 is not good for turbo , it is high CR bla bla bla
Here are 3 new turboed S38 - I know 3-4 more and this winter 4-5 will be ready - S38 is perfect engine

Yes, but they did exactly what was necessary to do it properly, they dropped the compression ratio! That is what you need to do, which on an engine like a highly stresed, highly tuned, high compression S38 engine is the opposite of what it's about!

This is why there are so few about. What's the point? Why not do it to a cheaper engine with more gains to be had? If you want bangs for your buck, nitrous an early 540i!!


Alpina did a stunning job on the E34 B10 BiTurbo

New forged Mahle pistons to get the ALL CONQUERING REDUCED COMPRESSION RATIO </rant> of 7.2:1, uprated con-rods, completely revised cams, new valves, all the engine management remapping that little lot involved. They also custom built a system drilling holes so oil could be sprayed on the underside of the pistons for more cooling. Did I mention the compression ratio came down?
Add in the cooling intakes and the stainless steel exhausts, intake and water coolers, new Motronic, to handle the lowered compression ratio, new intake manifold and you can see why a £30,000 535i suddenly became way over twice that! Even the throttle bodies are the opposite side to my humble 535i so there doesn't have to be a pipe going over the top of the engine. Oh, lets add diff-oil cooling systems, lowered compression ratio, revised bodykit, lowered compression ratio, bigger fuel tank, lowered compression ratio, new LSD diff, lowered compression ratio, uprated axle, lowered compression ratio, all the interior trim, lowered compression ratio, new suspension, lowered compression ratio, the wooden Alpina bits too... plus other stuff I can't recall!!

Also, if my memory recalls correctly, they may have made the pistons squash the air a little bit less than before, but I'm not sure of the technical term for it, although I understand it's quite important if you're gonna add a turbo...




You can go fast in a S38, but it's a law of diminishing returns. Kamikadze has already put a S38 into a 3 series, taking loads of weight off, so if he really wants to go much faster, he ought to buy Vidar Strand a Sunseeker and ask him what black magic he worked on that mad mad mad 1000bhp M5, although if you take one look at the engines layout... well... better make it two boats!


Anyhoo. Flame suit on, I'm going down the pub!


Ivan

 

[D_C_R]

A well sorted and well constructed turbo charged car will have no more issues to deal with then any N/A car. It will last as long and will run as well. Less fuel consumption is normally bi-product of FI.

Do it once and do it properly. The S38 could quite easily be turbo charged if lower CR pistons and the correct internals were used. The Middle Eastern and Asian cars even got the lower CR pistons anyway.

People are scared of turbo charging their cars because of the myths spread by those who have tried to take short cuts and had issues.

As for Vidar Strand's 1129hp monster, I believe it went bang again recently.

 

[WylM5]

A well sorted and well constructed turbo charged car will have no more issues to deal with then any N/A car. It will last as long and will run as well. Less fuel consumption is normally bi-product of FI.

Do it once and do it properly. The S38 could quite easily be turbo charged if lower CR pistons and the correct internals were used. The Middle Eastern and Asian cars even got the lower CR pistons anyway.

People are scared of turbo charging their cars because of the myths spread by those who have tried to take short cuts and had issues.

I pretty much agree which is why I pointed out the Alpina. But I still think that turbo charging even when done right creates lots of stress that a n/a engine does not see. Just the sheer amount of heat that the things makes will cause extra stress on the engine not to mention that it just ads to the amount of parts that could potentially go wrong.

As Ivan stated I really don't see the point of turbo or super charging the S38. Why not just f/i to a 535 or 540 as they are both cheaper engines and parts can be found much more readily. Heck just check out Jimmy's supercharged 540i- I think it has been fairly reliable for him and the thing beats out a E39 M5 easily (even with a auto box tranny!).

 

[BURTON]

Also you sometimes get a sponge power band, where you nail it and nothing and then a big dollop of power kicks in. N/A engines you don't get this!

 

[D_C_R]

Also you sometimes get a sponge power band, where you nail it and nothing and then a big dollop of power kicks in. N/A engines you don't get this!

Thats becasue you are using the incorrect size turbo.

 

[BURTON]

Nah thats cos you have lots of power!!! Cossies used to do this and they were standard.

 

[farrell]

Thats becasue you are using the incorrect size turbo.

In this case, we are talking 200 bhp per litre so is it as simple as that ?

To get 800 bhp from say, 3,795cc what would you recommend in terms of Air ratio on the exhaust & compressor hsg ('s) of the turbocharger ('s) to prevent the non linear delivery that would certainly exist with a single gas driven charger to generate the gas low volume & speeds to produce this power.
What are the aerodynamic profiles of the Turbochargers & what how much air can they compress at a given speed before the unit ('s)starts to surge ?
How much would you lower the compression ratio to burn the reqd volume of compressed air & fuel to prevent pre-ignition.
Would you attempt this with the high lift short duration cam shafts that are already present on the S38 series.
What would the Delta T heat rejection figures be across the thermostat hsg with the thermostat jacked open, hot to cold side @ wot.
Bottom hose & top hose temps for instance, & what would they indicate.
Can you increase coolant flow around the head & block or are you just going to increase cavitation of the parts
What methods would you undertake to establish your theoretical figures.
Those figures will also reveal if you are tempering back the major castings or not. The forged parts will take far more extremes of temperature traditionally.

What would the exhaust gas temperatures be as they would define the chemical make up of the manifold & even the method of clamping the head & using what material in that head gasket or coopers rings even.

Did anyone mention CFD analysis.

The chipshop tuners often take the "slap on a metal matrix composite head gasket that would guarantee to lower the comp ratio & with a bit of luck counter the increased thermal expansion ratios of the head & block due to the vastly increased combustion temps & pressures" & then play around with various size Turbochargers, thumbing through the hysteresis graphs for each one struggling to understand how fast & how much pressure could be extracted before the theoretical surge profile for the pump was exceeded & at what rpm & with how much manifold pressure.

You can achieve some results by intuitve experimentation but scientific testing using metallury, thermodynamics, principles of thermofluids etc are the formost methods of understanding what can be acheived supported by calibrated durability testing.

200bhp per litre is easily acheivable but there is still loss of driveabilty & durability where you are only having a 10,000 mile engine.

Im a test engineer for a living so Im always interested in new & cost effective technology that I can apply in my work.

Farrell
Bsc Hons Mech Eng

 

[WylM5]

In this case, we are talking 200 bhp per litre so is it as simple as that ?

To get 800 bhp from say, 3,795cc what would you recommend in terms of Air ratio on the exhaust & compressor hsg ('s) of the turbocharger ('s) to prevent the non linear delivery that would certainly exist with a single gas driven charger to generate the gas low volume & speeds to produce this power.
What are the aerodynamic profiles of the Turbochargers & what how much air can they compress at a given speed before the unit ('s)starts to surge ?
How much would you lower the compression ratio to burn the reqd volume of compressed air & fuel to prevent pre-ignition.
Would you attempt this with the high lift short duration cam shafts that are already present on the S38 series.
What would the Delta T heat rejection figures be across the thermostat hsg with the thermostat jacked open, hot to cold side @ wot.
Bottom hose & top hose temps for instance, & what would they indicate.
Can you increase coolant flow around the head & block or are you just going to increase cavitation of the parts
What methods would you undertake to establish your theoretical figures.
Those figures will also reveal if you are tempering back the major castings or not. The forged parts will take far more extremes of temperature traditionally.

What would the exhaust gas temperatures be as they would define the chemical make up of the manifold & even the method of clamping the head & using what material in that head gasket or coopers rings even.

Did anyone mention CFD analysis.

The chipshop tuners often take the "slap on a metal matrix composite head gasket that would guarantee to lower the comp ratio & with a bit of luck counter the increased thermal expansion ratios of the head & block due to the vastly increased combustion temps & pressures" & then play around with various size Turbochargers, thumbing through the hysteresis graphs for each one struggling to understand how fast & how much pressure could be extracted before the theoretical surge profile for the pump was exceeded & at what rpm & with how much manifold pressure.

You can achieve some results by intuitve experimentation but scientific testing using metallury, thermodynamics, principles of thermofluids etc are the formost methods of understanding what can be acheived supported by calibrated durability testing.

200bhp per litre is easily acheivable but there is still loss of driveabilty & durability where you are only having a 10,000 mile engine.

Im a test engineer for a living so Im always interested in new & cost effective technology that I can apply in my work.

Farrell
Bsc Hons Mech Eng

Oh darn I was just going to say that. But now I'll look stupid for posting the same thing so instead I'll just go outside and apply the knowledge that I do posses-push down on the right pedal make me go fast!

 

[D_C_R]

Great reading Farrel, your degree has paid off for you. At no point was I mentioning 800hp in my posts. I was simply stating that a turbo charged cars do not need to sufffer any more than NA. I was talking about the everyday world we live in, not the one people with rediculous amounts of money do that can afford the time and money needed to achieve 800hp.

Perhaps I needed to explain that in my initial post. My bad.

Dave
Bsc Common Sense (hons)

 

[farrell]

Great reading Farrel, your degree has paid off for you. At no point was I mentioning 800hp in my posts. I was simply stating that a turbo charged cars do not need to sufffer any more than NA. I was talking about the everyday world we live in, not the one people with rediculous amounts of money do that can afford the time and money needed to achieve 800hp.

Perhaps I needed to explain that in my initial post. My bad.

Dave
Bsc Common Sense (hons)

Hi Dave

Nice comment about the degree.
It is'nt worth much in reality & commonsense plays a huge part as you neatly put it..!

I felt that the whole thread was about enormous power to start of with.
The link to the very first thread to the bimmerforums from Kamidkaze has reference to 827 bhp & this guy vidars 1129bhp more or less set the scene.
I took the 827bhp as the conservative side of the figures listed under one of the pictures in the link as that is still pretty extreme.

In context of those figures & the swept volume of our engines, it became quite obvious the off boost performance would be noticeable just due to those figures, even with two unequal size Turbochargers
I totally agree that forced induction can be reliable & you can get something for nothing as its exhaust gas energy doing the work.
I still work on forced induction vehicles & prior to this M5, owned turbocharged cars for some 13 yrs, the last of which was the car you ozzies fondly refer to as Godzilla.

I was put on to the Skyline by my mates from Oz whilst working with them on the Falcon XR8 at Tickford.
That for me was the ultimate Turbocharged monster & I ran that with over 450 bhp, but it lasted over 80,000 miles before the internals let go & it did so in real style.

So I guess as with all things, its easy for us all to pick out pieces in threads that get us going.

No hard feelings & your point is well made & understood.

Regards
Farrell

 

[D_C_R]

No hard feelings at all.

Some nice work being done here to my friends M Coupe. Currently the fastest street registered one in the world. This car was up untill it had the cage and chute fitted driven daily.

http://www.bavariacars.com.au/article/?id=37

Cheers
Dave

 

[M5 powered]

No hard feelings at all.

Some nice work being done here to my friends M Coupe. Currently the fastest street registered one in the world. This car was up untill it had the cage and chute fitted driven daily.

http://www.bavariacars.com.au/article/?id=37

Cheers
Dave

Very well thought out car. I'd imagine the boost stays a MIN, when tootling round town. Thanks for posting the link.