New Here -Supercharged 535i

[Bwaterman]

Hi Guys I'm new to Bimmerforums but I've had BMW's for a few years, this is my 2nd. I'm a final year Mechanical Engineering student so I do all my own work on the car and am constantly thinking about what I'm going to change next.

Car Details:
1991 e34 535i
Manual

Engine:
m30b35
Autronic Sequential Fuel Injection
Lysholm Twin Screw supercharger
Remote mount oil filter
M5 Headers and Exhaust

Chassis:
Lowered springs (not sure what, but I'm planning to change to eibachs soon)
Koni Adjustable Dampers
Polyurethane control arm and Thrust arm Bushes
Cheap 17" wheels, but decent Tyres

Exterior:
Hella Clear lens' all round

Interior:
Schwartz Leather
2x10" JBL subs running off a Rockford Fosgate Amp

The supercharged was added by the PO but I bought it as an unfinished project which I am neatening up.

[cmgreensr]

Very nice, welcome aboard!

[xatlas0]

That is a heck of a snout on the charger. What size unit did the PO go with?

[89 bimmer]

Looks like the car was well taken care of. Congrats on the buy, and welcome!

[AHenry014]

thats very cool

[mikemxbike4]

Very cool indeed. I believe this is the first supercharged 535i I have seen

BTW, I am Mechanical Engineering student as well

[clevertd]

Welcome to the board! Interesting set up you've got there. I graduated with a BSME in May '10, seems like there are a few of us lurking around here.

[bblazen]

any idea about hp/tq?

[darrenforeal]

welcome! sick ride

[Binjammin]

Well that's an oddball.

[bmw525i justin]

Please excuse my French... but holy hell.
Can I HAVE IT!!

[m60b30530i]

Very cool indeed. I believe this is the first supercharged 535i I have seen

BTW, I am Mechanical Engineering student as well

RedFive had a supercharged 535, I have his black car now minus the charger .

OP that setup looks interesting, what brand is the supercharger ?

Why is there no vacuum hose on the Fuel pressure reg, and are you using the stock ECU ? don't see a air metering device. Please enlighten us, for this is a interesting build.

http://www.lysholm.us/

[Binjammin]

OP, is that water or meth injection?

[E34N]

Well then, that is one way to make an introduction.

Welcome.

[87shark]

Do want. He have a nice supercharged 535i that drive around atl. First one i have seen that was twin screw.

[Bwaterman]

Thanks all for the kind words.

The supercharger is a 1600cc Lysholm unit, its a few years old and I can't find much information about it. It is running 10psi which means the blower is a little smaller than optimal but manages to hold 10psi to about 5500rpm then boost falls off a little.

The fuel system is Autronic which is a MAP (Manifold Absolute Pressure) based system so nothing is needed in the intake. By removing the vacuum line from the FPR it means it maintains a constant pressure at all times which makes tuning a little easier. Even when it is connected the FPR doesn't adjust the pressure that much so it doesn't make a whole lot of difference.

No there isn't any water injection at the moment however I plan to add switched water injection later, so it can be used for overtaking and 1/4 mile runs.

PO has a time slip for a 13.5 sec 1/4 mile with an ok tune so hopefully I can improve on that a little, swapping in an LSD alone should bring that down a bit anyways. I estimate the power to be about 350hp at the crank but I'm not sure about the tourque. The fuel map is pretty close to being done now and the timing map is reasonable but conservative. I'm planning to tune it on a dyno in the next few months.

[SawheadE34]

holy hell! Nice catch.

[NikosX]

Neat car. Do something about those wheels.

[uk525td]

man thats sick
i havent seen a proper SC on a BMW... makes me want to make space in my m50 bay :P

[DUDMD]

Excellent intro, and an awesome ride.
That's what the 535i should have been stock.
Care to make a quicky video? would like to see/hear this car in action.

[zubbie]

The one time that RHD is a benefit. That setup would not work in NA. Nice clean install

[1cut808]

Hey Hey.... Another Aussie and one from WA which is even better....

Nice 34 you've got there... Are you on http://www.bimmerclubinc.com as yet? If not you better get on there as there are a heap of WA guys...

Mitch

[crazyrobbery]

your car looks great... Welcome

Looks like your off to a great start.

[5mall5nail5]

Thanks all for the kind words.

The supercharger is a 1600cc Lysholm unit, its a few years old and I can't find much information about it. It is running 10psi which means the blower is a little smaller than optimal but manages to hold 10psi to about 5500rpm then boost falls off a little.

The fuel system is Autronic which is a MAP (Manifold Absolute Pressure) based system so nothing is needed in the intake. By removing the vacuum line from the FPR it means it maintains a constant pressure at all times which makes tuning a little easier. Even when it is connected the FPR doesn't adjust the pressure that much so it doesn't make a whole lot of difference.

No there isn't any water injection at the moment however I plan to add switched water injection later, so it can be used for overtaking and 1/4 mile runs.

PO has a time slip for a 13.5 sec 1/4 mile with an ok tune so hopefully I can improve on that a little, swapping in an LSD alone should bring that down a bit anyways. I estimate the power to be about 350hp at the crank but I'm not sure about the tourque. The fuel map is pretty close to being done now and the timing map is reasonable but conservative. I'm planning to tune it on a dyno in the next few months.

It actually makes tuning harder. If your fuel pressure is 45 psi base pressure (which is typical of the older cars) then that means you spraying fuel into the intake at 45 psi (roughly) at the injector tip when the car is not in boost - meaning you need to squirt the injectors for shorter amounts of time. If you have decently large injectors you always fear as a tuner that you will have "too much injector" at idle. So one saving grace on a standard FPR car is that although you might have huge injectors, when idling your fuel pressure is lower (due to vacuum on the diaphragm). However, it also means that when your supercharger is making boost you are spraying fuel into the intake manifold at 35 psi, because theres a 10 psi environment that is back-feeding against fuel pressure, which means your fuel has a harder time "getting into" the intake manifold. This is why the stock FPRs are great - at vacuum situations you don't need tons of fuel pressure so the fuel pump doesn't work as hard, and then when you add boost the FPR are 1:1, meaning for every 1 psi of manifold pressure they see, they increase fuel pressure 1 psi. This means that your fuel injectors are injecting at a more constant pressure which makes things easier.

If you have 0 psi you might be injecting at 45 psi. If you have 15 psi you might be injecting at 60 psi, but since its injecting into a pressurized environment, the fuel coming from the injector is at that same relative 45 psi (60-15=45).

Otherwise, interesting build. Do you know if its an Autronic SM2 or SM4 or SMC ECU?

[m60b30530i]

Changing the oil filter must be a pain (if its in the stock spot). Were exactly is the remote filter ?

I wonder if the NA guys converted to Rack and pinion, we could possibly fit a similar setup. I had a chance to grab a SC from a tbird, could of test fitted that.