Which 24v to buy?

[winstontj]

Debating the 24v move over building an all out (~$8k) m20.

What motor is the highly desirable one? Is it the M5 motor? Where can I go to learn as much as possible about this? I've searched here but gotten little? Is this fairly bolt in or will I need to chop the tunnel to fit a gearbox? Subframe mods?

Can this be done on a budget of $8,000? I would usually tell someone: double your time and budget... In this case I can not. $8,000 - $10,000 is the MAX I could spend.

Would I be better off building an M20? I think I have a lead on a motor from an M5 with dogleg gearbox, 130k for ~$3,000 should I get it?

TIA,
TJW

[browntown]

refurb'd s50 total install should go in for under 8k pretty easily. Theres a whole post dedicated to it. Start there. http://www.r3vlimited.com/board/showthread.php?t=45442

[matt]

$8k is very possible, even making some mistakes.

Buy a motor from a salvage yard with a WARRANTY. Can't stress this enough.

[Jean]

refurb'd s50 total install should go in for under 8k pretty easily. Theres a whole post dedicated to it. Start there. http://www.r3vlimited.com/board/showthread.php?t=45442

+1.

8k on a m20 is for 8k-10k maybe you can get an s38 from a wrecked car even. Who is going to do labor/install ?

[KangamangusDriver]

S52!

Convert a OBD2 S52 to run on OBD1 electronics.

That is the route for high Hp while staying NA.
Obsviously do a build when you have it out of the car.

[FredK]

If you can get your hands on an S38 with 130k for $3k, you can probably get it done for less than 8K. The S38 essentially bolts in like an M30. You're probably better off asking how difficult it is to bolt up an M30 in the M30 swap forum.

If I were you, I'd just do an S52US with all the bolt-ons and call it a day. Stick on a VF supercharger if you want a little more juice. The attractiveness of this solution is that it is brainless to source another S52 should it blow up, and a refresh costs around $2k, not $10k.

[winstontj]

The motor is out of a 1995ish ///5 with dogleg box attached. I'll totally rebuild it, cams, pistons, intake, exh,etc. so warranty is no issue. I will do the labor. I will also (probably) go standalone and stay NA.

I **think** I want an M motor ...

[backtrail69]

I think you will run out of money if you try to do all of that to a s38, they are very expensive motors. I would go obd1 s52us w/ cams, euro HFM, 24# injectors and a chip and call it a day.

[FredK]

You'd be hard-pressed to do a S38 rebuild and swap for 8-10K.

You'd be hard pressed to do a rebuild and swap of an S50US for 8K, AND use a standalone EMS. That is just crazy talk. You'll need Pentagon-levels of budget and time. All this to fix a headgasket leak!

[gazellebeigem3]

i hear that the duratec 24v from the ford taurus is very desirable.

[BigD]

The motor is out of a 1995ish ///5 with dogleg box attached. I'll totally rebuild it, cams, pistons, intake, exh,etc. so warranty is no issue. I will do the labor. I will also (probably) go standalone and stay NA.

I **think** I want an M motor ...

So you're saying you've found one of the rarest BMW engines (S38B38 - being a 95ish) and gearboxes (E28 dogleg) for 3000? Unless you've found a complete moron or a spiteful ex-wife, these are going to be in such piss-poor shape that by the time you get done rebuilding them, you would have had a 400hp S52 or 500+++ hp M30 for less money.

The only good thing about having an S38 is claiming that you have an S38, that's it. There are several lighter, cheaper and more powerful (for the same $) options which are also way easier to install.

[e30polak]

well then again ur starting out w/ a 340hp vs. a 240 hp engine
if u have the $ to maintain the s38, cuz i heard they get pretty expensive...other then that the s38 is an amazing engine, and unless u drop like 3k on an s50/2 to make it have 340hp NA, or drop a 3k+ turbo setup , i'd say start small with the M5 motor and build it up later...do u realize how fast 340 hp is in an e30??? this is simply my opinion, b/c i'm in luv with the s38 :puppy:

[BigD]

well then again ur starting out w/ a 340hp vs. a 240 hp engine
if u have the $ to maintain the s38, cuz i heard they get pretty expensive...other then that the s38 is an amazing engine, and unless u drop like 3k on an s50/2 to make it have 340hp NA, or drop a 3k+ turbo setup , i'd say start small with the M5 motor and build it up later...do u realize how fast 340 hp is in an e30??? this is simply my opinion, b/c i'm in luv with the s38 :puppy:

An OBDI S52 is not 240hp and I have NEVER seen an S38B38 dyno at 340hp, even low mileage euro cars that have been meticulously maintained since day 1. They are extremely strained and overexaggerated by the factory. And if you drop 3k on an OBDI S52 you will be making a "bit" more than 340hp, certainly more than the under 300 ft lbs of torque the 3.8 makes. They also weigh an obscene amount.

A proper rebuild will cost an insane amount (don't ask how I know). Pistons are 5-600 each, or 1300 for JE pistons (I put these into mine, 95mm). Valves are like 300 each for an exhaust, like 200 for an intake. 24 of those, do the math. Cams will cost you thousands regardless. And this is just the tip of the iceberg. Even the best machine shops won't dare to make shims for these heads, since they must be accurate to like the thousandth of an inch, so a valve adjustment alone will cost you hundreds of dollars and if you don't do it every year, 2 max, you'll need a head rebuild (see above cost figures).

NOT worth it. It's a nice dream, move on.

EDIT: It's a racing engine. It was designed to receive thorough attention after every major outing, BMW simply adapted it for a street car by making it milder but it's essentially the same 9000rpm 400hp+ motor that was in the racing CSLs and M1s.

[smonkbmw]

if i had to do it all over again and had $8k to spend. id find another m52, swapped to obd1 and do the 2.9 liter stroker. thats more power in a e30 than anyone needs. if that isnt enough add a c30.

[FredK]

An OBDI S52 is not 240hp and I have NEVER seen an S38B38 dyno at 340hp, even low mileage euro cars that have been meticulously maintained since day 1. They are extremely strained and overexaggerated by the factory. And if you drop 3k on an OBDI S52 you will be making a "bit" more than 340hp, certainly more than the under 300 ft lbs of torque the 3.8 makes. They also weigh an obscene amount.

To get 340 flywheel hp from an S52 you will have to do headwork and move to aftermarket pistons for higher compression. Even then you probably won't hit that target. The head is breathing limited at the top end, and while this can be somewhat mitigated with some headwork, it will certainly cost more than 3K.

Also, the S38 weighs within a few kilograms of the S50 Euro engine.