MyE28.com

I've been trying to think of ways to fit a turbo(s) on the 540i, and nothing seemed to work out without MAJOR exhaust modifications, and I haven't gotten over how much work it was just to make the left bank header, so I'm not about to make new headers for this thing. But recently a friend has been telling me I should install a turbo further downstream. I was then thinking about taking the spare wheel well out and installing a turbo or turbo's.
My real question is how much boost would I lose if any running the pressure pipe all the way back up to the intake, and is this a good idea? Anyone have any experience thoughts on this type of setup. I saw it on a camaro the other day and thats what got the ball rolling.

Downstream turbos have become big with the 'murican muscle crowd. Apparently you don't gain too much turbo lag because you don't have the crazy heat in the engine compartment. I say go for it. I'll even help you out. Good luck.

There was a discussion about this over on BimmerForums.com the other day, though it was in reference to 6-cylinder E36 M3s. The general consensus was that it isn't a good idea because of the loss of heat (energy) which really makes the turbo spool. There's also a lot of piping, and I don't see how you can get the charge air back up front without losing pretty much all of your ground clearance. Running the charge air pipe this far will also cause more lag, but it probably wouldn't be terrible.

Certainly, you can do it and it will be better than no FI, but it's not ideal.

For your application, I think a supercharger would be better. That's probably one of the only times I'll say that, but it's the truth.

Jeremy

Man I would go with a supercharger in your case - you have no extra room for the turbos and a supercharger requires no exhaust modifications.

Tjn182 wrote:Man I would go with a supercharger in your case - you have no extra room for the turbos and a supercharger requires no exhaust modifications.

Amen, Dinan used a Vortech as I recall, so you could probably source one of those. I'm sure there are pics of supercharged 540's and whatnot out there somewhere to give you an idea of how it all fits together.

450rwhp blower setup http://www.icsperformance.com/rides%20dc540%20final.htm

jon volk wrote:450rwhp blower setup http://www.icsperformance.com/rides%20dc540%20final.htm

Wow that is really nice..

Aaron,

In your case the rear mount turbo is a good option. You can probably do it on the cheap and it will work fine considering you already have 240rwhp. I can help you with the turbo selection if you decide to go forward. I say go for it. It's gotta work better than a centrifugal supercharger.

Todd

The first thing I thought when I saw the ICS setup... "What a crappy compressor outlet orientation"... kinda like driving your car into a solid wall THEN making a turn.
Turbo in the back will work fine... it's just not optimal. The closer you can keep it to the engine the better... more heat energy, shorter charge air and intake air runs.

That elbow is there even with the stock blower setup. There is also not room for any larger of a radius. Not suffering from heat soak > a harsh turn IMO.

I see several options....

The company thats making the rear mount turbo is Squirre Turbos:
http://www.ststurbo.com/

The modern cars don't suffer from turbo lag with these systems as bad either is that these systems are relatively low boost on high compression engines.

But I agree, the easiest solution is a SC. Thats why almost all the tuners are doing SC's, easy to install, less parts, less complication.

RussC

Sweeney wrote:I see several options....

ICS doesn't have a Bridgeport, lathe, mill or a person who can operate those and a person who can hand hammer aluminum to any form they desire.

T_C_D wrote:

Sweeney wrote:I see several options....

ICS doesn't have a Bridgeport, lathe, mill or a person who can operate those and a person who can hand hammer aluminum to any form they desire.

Well, they did a nice job on that grossly undersized and inefficient intercooler...

Sweeney wrote:

T_C_D wrote:

Sweeney wrote:I see several options....

ICS doesn't have a Bridgeport, lathe, mill or a person who can operate those and a person who can hand hammer aluminum to any form they desire.

Well, they did a nice job on that grossly undersized and inefficient intercooler...

Well, while I agree that IC is not perfect, its only a low pressure system, so lots of IC'ing isn't a must. You can run 5-6psi w/o an IC, Dinans original kits did, and still do for the entry level stuff.

RussC

That's news to me, Russ..... oh wait, no it isn't... we ran around 12 psi non-intercooled for some time and still offer it as a Stage 1 kit. For the claimed 450rwhp they may do better without the intercooler as its significantly undersized charge air face is resulting in a serious pumping loss. 8)

Sweeney wrote:That's news to me, Russ..... oh wait, no it isn't... we ran around 12 psi non-intercooled for some time and still offer it as a Stage 1 kit. For the claimed 450rwhp they may do better without the intercooler as its significantly undersized charge air face is resulting in a serious pumping loss. 8)

Hey, Im not trying to throw you under the bus, in fact, I mostly agree with you.

But, the M30 systems with no IC are 8:1, the newer E36/E46 are all 9.5-10:1+. 5-6psi is a little tougher non-IC'd. I agree that that IC is not optimal, and is lossy, but when your only running 5-6psi into the manifold, it can work. If you going higher than that a more efficient bigger IC is a must.

RussC

Russ, my point is, with ICS' reputation and what that system cost, it's design is rather amaturish IMHO.

bmw4aaron wrote:I've been trying to think of ways to fit a turbo(s) on the 540i, and nothing seemed to work out without MAJOR exhaust modifications, and I haven't gotten over how much work it was just to make the left bank header, so I'm not about to make new headers for this thing. But recently a friend has been telling me I should install a turbo further downstream. I was then thinking about taking the spare wheel well out and installing a turbo or turbo's.
My real question is how much boost would I lose if any running the pressure pipe all the way back up to the intake, and is this a good idea? Anyone have any experience thoughts on this type of setup. I saw it on a camaro the other day and thats what got the ball rolling.

I like the installation you've done on your car. The V8 is a great design and putting a turbo in the back, while less optimal from a thermal efficiency standpoint, offers the advantage of getting some weight to the rear of the car and off the front.

If you look at how long the pressure circuit is on the ICC Performance installation (and most are this way), the rear mounted turbo is only incrementally longer. Also, running the compressed air back to the front will give it a chance to cool.

Depending on how crazy you want to get, the rear mounted turbo has some huge advantages from a packaging and design standpoint...

What kinda power you think you could get outta the 540 with that rear mounted system?

It depends on the boost level.

If low pressure 5-6psi and no IC, ~100hp increase over stock. As you add stuff and increase boost, the power will increase.

Whats the stock power from the M60, ~272hp crank?

RussC

russc wrote:It depends on the boost level.

If low pressure 5-6psi and no IC, ~100hp increase over stock. As you add stuff and increase boost, the power will increase.

Whats the stock power from the M60, ~272hp crank?

RussC

Yeah I think the power is 272 or 282...around there...

what do you think could be the max power on stock internals with the proper IC and 'stuff' as you call it...

Well,
Add custom programming and tunning with all the proper stuff and you can get boost to ~11psi with that kind of compression ratio. So add ~200hp crank to ~472hp.

11psi is what the M52 guys can do with stock compression and internals. Any more than that you have to add a serious W/A injection system for say another 2psi, so call it 500hp on stock internals. I don't think if you use that kind of boost alot the iternals will hold up for long.

RussC

rundatrack wrote:

russc wrote:It depends on the boost level.

If low pressure 5-6psi and no IC, ~100hp increase over stock. As you add stuff and increase boost, the power will increase.

Whats the stock power from the M60, ~272hp crank?

RussC

Yeah I think the power is 272 or 282...around there...

what do you think could be the max power on stock internals with the proper IC and 'stuff' as you call it...

286hp with 10:1 compression, i wouldn't go any higher than 8psi. I'd also go megasquirt.

T_C_D wrote: the rear mount turbo is a good option.

Just wondering ... I'm not sure how the air is metered on the M60, but it seems that one of the options in this situation would involve metering after boost. Would that present any serious issues? If so, seems you would either have to either filter/meter under the hood, run the air to the back, boost, then run it forward, or move the filter and meter back near the turbo.

Look at STSturbo's web site and see what their doing.

RussC

If it were me I'd be real cautious about boosting an M60/M62.. they don't like a lot of pressure from what I know.

A friend of mine has a blown E38 740iL with a 6-speed.. he's got a long block built up by VAC, apparently much past 6psi and these blocks get unhappy.. he had big blowby issues with an ESS kit.

I'm planning on running 6psi on my 740iL with an M62.. but I'm running stock internals because I dont mind swapping out long blocks. I also have an extra M62B44 long block lying around. I'd love to run around 9psi but it's more work than I have time to do in the near future.

I recently had a 2004 Pontiac GTO, 5.7 with an STS rear mounted turbo kit. All I can say is that the kit was excellent and the power very linear. No turbo lag!!! I read for 6 months in different forums how the setup won't work, too much turbo lag, garbage science, etc. Well, all of that was BS, it does work and work well.

It should tell you something when the people we look up to here in this forum for turbo advise, TCD, recommends using a rear mounted turbo.

I say go for it. Work with TCD or Rick Squires to match the right size turbo to your car and it should work out great for you if you do it right.