View Full Version : E34 525 Options - S50/52?

12-30-2004, 11:46 PM
Alright, after thorough searching, I've realised unless I commit myself to a 535 which is a "Not so commonly modded" car, I am SOL for a decent powerplant (automatic is not an option, and every 5spd [haven't found any 6spds] 540i has been poorly maintained)...

So this leads me to wondering if it would be a decent idea to get a 525 with an M50, and do an S50/52 swap. It's a very commonly modded engine, turboing it wouldn't be a problem (M30 would need custom headers, no?) and there's lots and lots of aftermarket for the specific engine, and much more support.

I don't enjoy being a sheep and doing something easily possible, but I'd rather not go through so much effort for an engine with fewer performance options...

I figure I could even just mod the M50 if I couldn't find an S50/52 to swap in... 400 horse turboed is EASY to attain on any 2.5l engine (I6 anyways). And then the S50 would just need the same kind of engine work and it'd be bolt in to the already built turbo design.

Yes, big power into an E34 is what I have in mind (In the end I'd be looking around 600HP I imagine).

Any comments, ideas?

Don't tell me to search, the search on this forum sucks (IE it excludes everything except engine swap), and on DTMPower it's a crap load of criticism every time someone posts about S50s in E34s.

Also, M50s were first in 94 E34s or 93s? Just wondering.

12-31-2004, 06:54 AM

Me too...More power into our E34, ehehehe

M50's were first in 93's

Lee in Ottawa
12-31-2004, 11:13 AM
I know it can be done, try searching s50 swap into 325s or something on bf. Personally i say stick to boosting a m30. That was my plan originally until priorites changed. It just seems that when u read on bf about all the boosted m3's they all have problems and all need alot of tuning and money to be reliable, where as with the m30 all u do is visist turbochargingdynamics.com and 7g's cdn later u have close to 400rwhp reliable. s50 swap plus turbo kit, lets say AA, ur now up to some big bucks for the same result. Just my opinion. Check out www.mye28.com they have a turbo form and read about all the happy m30 turbo owners. Anyways good luck on whatever route you take.


12-31-2004, 11:17 AM
I'd go with a 535 and then put an order in with:


You'll be ahead both in cost and hp

12-31-2004, 05:49 PM
Turbo Dynamics kits are crap (yes, I just called them crap). For their purpose, they're only okay. The design of them, and purpose is for light duty street setups. Unless I want an absolutely massive water tank with an even bigger heat exchanger under the rear of the car (or bottom, or front, whichever is least likely to get ruined, aka the rear) it will work like crap for what I have in mind.

Air-Water intercoolers from them are not designed for heavy usage (aka, you will superheat the air after using heavily), water becomes heatsoaked, it's NOT designed for anywhere near "Track use", why have a 600hp monster if you cannot use it for what you intend? Heat exchangers for water are a bitch to install, especially something like a BMW where routing water lines underneath the vehicle is the least conveinent thing on earth.

So you're going to say, but Water-Air can make the intake charge far cooler then air-air intercoolers... Yes, it can, however if setup properly, it isn't nearly as effective as air-air with water injectors for my purposes.

You guys ALSO need to realise that I am complaining because I would be building 90% of the setup myself, only things I wouldn't (or would rather not build) are the exhaust manifold, and the intercooler... All the piping etc would be done by me...

Also remember that the S50 weighs less than the M30 does.

As to the TCD kit pushing me to "close" to 400rwhp, I would rather spend my money on a 540i and drop $4000 on a supercharger setup and push OVER 400rwhp if I wanted that little power (yes, little). I had an old Mid-rear car, and it pushed 400/400 twin turboed, from a little 3.4l DOHC V6 (yes, the pos Chevy 3.4 TDC), with that car it was an autocross car, 400/400 was more than enough power because it got really good weight transfer because it is mid-rear. However I was stupid and sold it because I got bored of autocross.

I am looking to push 600RWHP PLUS... To me 400HP is nothing, my daily driver pushes over that much, my offroad rig pushes over that much aswell...

Race car is the term that will come to mind when I finally get finished. Show car aswell, clean, gorgeous, flawless install, and no big ass ugly water-air intercooler intake.

I am not saying turboed M30s aren't an option, I'm saying that an S50 turboed weighs less than an M30, and is a lot easier to get power out of without spending $$$$ on getting cams ground to my specs (assuming I can find unground cams, if not I'd have to get them honed out of a block of something).

01-01-2005, 02:47 PM
If you're looking at making 600 rwhp its been done a bunch of times with m30's / s38's.
I don't know of any s50's making 600rwhp - Dado's car is making something like 458rwhp at 17psi.

TCD's kits aren't crap - there's a couple people here in Toronto that are running them and putting out great numbers. You call them crap but don't say why - all that heat soak stuff you talk about is true for any turbo charged application.

m30's are heavier than an s50 but if you're worried about weight you wouldn't be buying an e34. Getting a cam ground to your specs for an m30 is affordable; and as opposed to an s50 you only need one and no special tools to install.

01-01-2005, 09:26 PM
Heatsoak does not occur in air-air intercooled applications (not in the same manner), it only occurs in water-air applications, the water eventually heats up to the same temperature as the engine bay, and heats air that would be cooler to begin with... Air-Air intercoolers avoid (not defeat) this by placing water injectors in front of the intercooler causing the water to be cooled as it passes through the intercooler as mist, and then into the intake of the engine...

With Water-air you would need to install a heat exchanger in the most effective spot on the car (aka, under the body, or the rear bumper), which means piping for it, installing a super-duty pump and worrying about damaging another very very easy to destroy object... There's a reason why drag racing is one of FEW worlds where water-air intercoolers are used over air-air... In boat racing, it's quite obvious why they do, they've got infinite water to cool with. This is the main reason why I called TCD setups crap, the other reason is for the cost... Not many water-air intercooled turbo setups cost that much for such a simple setup... Most include heat exchangers for that much, they're designed for street only driving if they don't, and are used as a shortcut because air-air isn't as effective in a street-only machine.

If built properly the S50s can easily handle 600RWHP, if built properly (IE, designed for it, including custom pistons/con rods/crank etc)... Dado himself has complained a lot about the work that AA did on his car, and says that it's a horrible setup, and poorly done. Especially for the price he paid, he basically admits to getting ripped off, big time.

If I could find an E30 M3, I'd get an E30 M3 and build that. I could handle the size for the sake of driving a super-rare car.

I don't want an E36 as I don't fit in them as well as I'd like (not for hard racing seats anyways), I don't want an E30 because it's too old (and small for that matter), and I don't want an E46 because I don't like them ;) I want an E34 because I love the design, and when lightened, it's not too too heavy (Considering I can drop several hundred pounds off of a 2400lb car, I think I can drop more than that off of an E34).

If someone can point out a good source for a turbo header for an M30, I might consider it, but try to remember I don't want a kit, I'm capable of building everything myself, or having it built, it's a matter of not wanting to build a turbo manifold.

Where can I get blank M30 cams anyways?

01-01-2005, 10:13 PM
Heat soak does occur even in non intercooled vehicles :p granted its worse in air / water.

Again name me someone with a 600 rwhp us spec s50 that's streetable.

TCD sells their manifolds seperately, so does pro turbo http://www.proturbo.fi/index_en.htm.

Schrick has cam blanks, race tep can regrind an existing cam to your specs http://www.racetep.com/

Lee in Ottawa
01-01-2005, 10:40 PM
Can you not run a air-to-air intercooler with the TCD kit?

01-02-2005, 10:28 AM
In Water-Air intercooled vehicles, heatsoak is disastrous if you're not setup to prevent it (which the TCD kit isn't, simply because every time you dragged the car on anything or got hit by any rocks underneath you'd wreck the heat exchanger lines or the exchanger itself)

I didn't say that there are 600RWHP vehicles running S50s that are streetable...
I said it's possible, could be the fact that Racegas (100 octane) is sold all over Calgary (10 pumps) and 3 pumps even have higher octane variants aswell as the pump at the track pumps just about everything you can imagine... Or run over to the airport and fill up on ultrarare 115/145 Avgas if you've got big enough injectors (less dense than racegas...)

I have places I can have my own cams ground, aswell as have my own parts cut from just about anything I want (including titanium if I feel like wasting money)... I just wondered who sold blanks.

Yes you can run air-air intercoolers with the kit, but at an even greater loss because it comes setup for water-air and you'd have to redo everything on air charge side of the turbo (and again, I don't want a kit).

Anyone know the quality of the TCD or ProTurbo manifolds? (Though 1000/1200CDN for a stainless manifold isn't exactly what I had in mind...) If they're any good, I might still consider an M30, pending I can find something I like and don't have to start from just a shell with....

01-05-2005, 09:23 PM
Can't you just run an air-air intercooler with the TCD kit?