Need experienced input: A Sophisticated S50 e30

[Ahheck01]

I know many of you appreciate the raw, brute power - the loud exhaust notes, the brutal roar of your swapped s50, etc.

But the thing about the S50 and S52 that has always appealed to me is the smooth, refined sophistication from 800rpm to 7200rpm. I need your input on what I need to do to make a swap that results in a smooth, brutally fast but not brutally loud e30 with an M3 engine. What exact engine? What should I do differently in the swap process to ensure I maintain the smoothness, and the quietness?

How difficult and expensive should it be? How much more difficult and expensive to add a 6 speed manual tranny, as well as an LSD in case I get an e30 shell without one?

Thanks for any and all input you guys can provide!

-Evan

[BimmerToad]

Just be sure you use big enough mufflers. Definately use both a big resonator and muffler. If you're not limited to a budget, go with the 3.2L so that you can run a tall gear in the differential to keep your cruising rpms down.

[1990m3]

i installed a '95 m3 exhaust system on my car earlier this week. I've got a S50 motor in there. My plan was like yours, I want it to stay quieter, at least for now. My other car is loud, I don't want all my cars loud. It sounds like a stock '95 m3 now. I had to have some custom pipes made for it to work, but it's a decent setup for now and with my motor upgrades it sure felt smooth and awfully fast!

[FredK]

Dynamat?

The reason why the E36 M3 is not that loud is because it has a decent amount of sound insulation, hence the car sounds quite different when you're outside as compared to when you're inside.

I think if you use the stock exhaust components you have a good chance of quieting down the E30 swap. Also, you should aim to get a post-87 325is because these cars have the most soundproofing out of all of the possible donor shells.

Also, like BimmerToad said, if you want quiet, you should definitely run a 2.93 or 3.15 (assuming you use the E36 trans), so that your highway rpms are low. Otherwise if you go with a 3.25 or higher, you'll be turning 3500 at 80mph. That's loud even in my E36 328.

An LSD usually runs between $175 to $350 depending on mileage, condition, and ratio. You will need a custom driveshaft to get the 6 speed to work. You will have to either mix and match front and rear driveshaft sections or get one custom shortened for this application. I believe Zionsville Autosport has a way to retrofit a 6 speed from the E46 330 and Z4 onto a M50 family engine. You could also use a E46 M3 transmission. Pretty expensive though. I don't think there's much of a knowledge base here, because a six speed is a very pricey option.

[hugh jass]

An enclosed airbox will also greatly cut down on engine noise. You'll have to have something fabbed up for the corner of the engine bay, but you'll reduce the sucking sounds.

[1990m3]

oh yeah, I have a 3.46 so i'm turning lots of RPMs on the higway, but it's all worth it when I give her hell!

They are right though, it sounds the loudest coming from my glove box/firewall area because I never re-installed that gasket around the ECU plug (will do that soon) and I haven't reinstalled the inside glovebox plastic panels. It makes some noise, but it's the quietest possible option I believe

dave

[Ahheck01]

Also, like BimmerToad said, if you want quiet, you should definitely run a 2.93 or 3.15 (assuming you use the E36 trans), so that your highway rpms are low. Otherwise if you go with a 3.25 or higher, you'll be turning 3500 at 80mph. That's loud even in my E36 328.

Wouldn't the six speed be the solution to a higher ratio, providing greater accelleration with a higher top speed?

[kylebes1]

Wouldn't the six speed be the solution to a higher ratio, providing greater accelleration with a higher top speed?

the six speed will give you the same top gear as an m20 transmission.

The regular e36 trans has a 1:1 fifth, the six speed has overdrive (.82 or somthing like that.)

If you have the m20 five speed you also get the overdrive, fourth is 1:1. The seperation of the ratios is greater than that of an e36 trans.

This is my recommendation for good acceleration and decnet highway rpms (about 3k at 80 I think):

m20 five speed- 3.46 (?) or 3.73 LSD (very easy to come by, stock on the 325is)
e36 five speed- 3.15 (?) or 3.25 LSD (e28 535is, swap the rear cover, possibly the output flanges)
e36 or e46 six speed- 3.46 or 3.73

I had a 3.73 LSD matched with the e36 five speed. It was very low geared. I think I topped out at 130, at the m50tu rev limit. usually like 4500 rpms at 80. I could go 25 in fifth, gun it and hit 85 or 90 in seconds...

As far as noise, the 328is exhaust pretty much bolts up, that will be nearly silent, and exhaust does not hurt horsepower too badly... m52 or s52 manifolds are superior to the m50 and s50 ones though.

The ulitimate engine is the European s50b32. Is actually an "M" engine... and had the six speed in 1999.

[1990m3]

yes, definitely go with the OBDII exhaust manifolds, they are much tidier than the OBDI cast iron ones

[Ahheck01]

The ulitimate engine is the European s50b32. Is actually an "M" engine... and had the six speed in 1999.

What are the odds that I can get a 4 door shell, and do an S50 swap all said and done for around 6k?

-Evan

[DanGillan]

easy, i'll sell you my non vanos m50 swapped e30 with quiet exhaust for 6k :) it will be done next week :)

[Ahheck01]

easy, i'll sell you my non vanos m50 swapped e30 with quiet exhaust for 6k :) it will be done next week :)

Depending on the condition of your car, I would seriously consider it for $4k or so.

-Evan

Edit:

Basically, my situation is that I have a highly modified e36 328i. I've spent 18k on it and will probably be extremely lucky to get 12k for it. I have 12k in loans to pay off, so I'm looking for another fun but less expensive car to get into. The insurance on a 318i looks pretty good, too. Heck, they don't have to know there's a 3 litre moster under the hood...

If I got into an M50 swap, then down the road I could drop in an S50 with little to no modification, right?

[FredK]

What are the odds that I can get a 4 door shell, and do an S50 swap all said and done for around 6k?

-Evan

You could do it if you get a hookup on the car. The uglier the car, the higher the probability that you can get this project done for around 6K. Also, if the car is a 325, you can save money by not having to get the coolant expansion tank, transmission, and rear differential.

I say, get a good donor car, and allow the expenses to fall where they may (closer to 7 to 8K) and happily drive a reliable and powerful E30 swap.

[DanGillan]

i was just kidding around, plus. 4k isnt enough :)

and yea technically a lot of the swap parts are the same, but depending on your m50 you may need wiring harness, definately an ecu, and various other engine specific parts, but yes, the majority of the work and most of the parts you would already have.

[kylebes1]

A s50b32 will cost you 6k alone.

I have an American s50b30 in my garage, with five speed and DME. Probably sell it for $2800.00.

I spent about $5000 on my first swap, but I got ripped off on my LWF and clutch kit...

PM me dude...