what to do what to do

[nickmpower]

Well im torn about what to do about an engine. I cant decide between NA stroker or supercharger or turbo possibly with the stoker crank. I basiclly want a really reliable engine that will last a long ass time.

Right now I'm leaning towards a stroker with some lower compression pistons maybe around 9 or so???? with the e36 computer and knock sensors and a turbo. It would be possible for me to just have a boost controller and run the turbo on very low boost most of the time and turn it up when wanted right? what managment systems should i be looking at? what turbo?

[sheepdog]

If you have the money, stroker.

If not, then it more or less depends on what you want to do with the car.
If you track it, a turbo can be good since you can keep the revs up and in the boost. It can also generate more power than a blower.
For street a blower is my preffered method as they generate low end torque, which is best from stop light to stop light, yet decent enough for track use. Blower is also nice as they are easy to install and create less engine bay heat. It is probably the most economical up front.

Just my opinion though, and I am not one of these people who think a turbo is god.

[2002maniac]

Cant decide? Why not a twincharged stroker?

[nickmpower]

would it be benificail to get a low mileage engine when i might just be replacing the crank and pistons anyways?

[sheepdog]

would it be benificail to get a low mileage engine when i might just be replacing the crank and pistons anyways?
That is really not all that needs to be done.
Granted if al you want is a stroker, you coudl possibly find someone to do it, but even then, the bearings will all be replaced, new rings, bored, honed, oil pump, timing chain, igniton, then they will refurb the head. Plus if they are smart they will also replace the starter and water pump, as both are old and the starter needs more power, or at least full power. If the radiator is not new, it will need to be freshened, same with the fan clutch, and clutch itself. The new power will probably destroy a 120k+ factory clutch. You probably will need a new chip as well.

Then there is trans and rear end which should at least be checked.

That is just off the top of my head.

No point in worrying about mileage, anything that wears is re-done. This is also why strokers are so damned expensive. You basically start with a rebuild and add on from there.

Rebuilt M42, expect $3500, without stroking.


Then you get into how much mre do you want or need. A stroker could use more air and fuel, so now you are looking at injectors, a custom chip ($00-$800), ported heads, ported intake, how about a new cam as well?

Strokers are truly the better way to go. You can increase milege (depends on the car, in this case, yes), the motor is rebuilt, rather than slapping a turbo or blower on a car with 120k+ miles, and you basically start with a larger factory engine, without a turbo or blower that needs rebuilding every 100k. Plus, this motor is not straining to make power any harder than the original motor.

For probably close to the cost of a turbo kit and rebuild, you can get a 2.0 stroker (built and bored over, not actually stroked). The turbo as well as the blower has more power potential, but places more strain on the engine, will not drive the same as a larger displacement, and will generally be noisier and generally have shorter lifespan.

If you really have the bucks a built 2.1 stroker with a turbo or blower would be the way to go though. 350hp M42 with a killer powerband anyone?


Honestly, there is no replacement for displacement, unfortunately in this case, another other addage also applies. "Speed costs money, how fast can you afford to go"

[nickmpower]

yeah thats what i was thinking about all the bearings and everything. Can 2 liters really be had with just boring? 86mm is what the 1.9 m44 is so what is required for 2 liters? i dont know if i would want to push the bore limits with boost. one part of me just wants to buy the 30k mile engine on ebay and throw it in, but i know i wont be happy with that later on.

[sheepdog]

It is actually like 1.92 liters you can get with just boring the block out mindlesly, but you can actually bore to 1.95 if you are willing and want to get custom pistons.

If you are going to supercharge, I would go with a light overbore and custom pistns. This way you retain cylinder wall thickness and lower the compression. Aim for like 1.9 or maybe 1.92 at most.

You are looking at over $4000 by the time you get the motor back into the car, even if you go with just a normal rebuild and bore it out. Without doing much of anything but rebuilding it.

[D. Clay]

What's the deal with the later model M42's? What kind of power and displacement are available by just buying a good used later model engine? Sorry if this is old stuff but I'm not that up on all the BMW models and what came with what.

[tim_s]

bolt a turbo on! there's not enough turbos on here! under different circumstances, i.e. if i didn't have a crappy rhd car with the steering in the way, UK fuel prices and UK insurance companies, I may well have gone down this route myself. our engines are pretty tough.
if you go turbo, Megasquirt all the way for fuelling imo.

[nickmpower]

i think ive changed my plans. low milage engine with either a low compression head gasket or low compression pistons. and turbo of course. then if need be i can build a better engine later one down the road

[kowalski]

bolt a turbo on! there's not enough turbos on here! under different circumstances, i.e. if i didn't have a crappy rhd car with the steering in the way, UK fuel prices and UK insurance companies, I may well have gone down this route myself. our engines are pretty tough.
if you go turbo, Megasquirt all the way for fuelling imo.

you finally get all your kinks worked out iwth your MS? i unfortunatly had a futile trip to europe this time arround which involved me bringing back nothing due to many events... so i'm going to see what happens. i Just got a pretty decent job this week so "fingers crossed" for me... as for MS make sure its working perfectly before you start cranking up the boost...

[nickmpower]

will MS allow me to have a couple differnet maps? i really want a low boost setting for cruising around and a high boost setting for the track ect. What other options are there?

[2002maniac]

will MS allow me to have a couple differnet maps?
yes

Can 2 liters really be had with just boring? 86mm is what the 1.9 m44 is so what is required for 2 liters?

The M44 has a 85mm bore.

M44 crank with 86.4mm bore (S52 pistons or custom) would give ~1.96 close enough that I would call it a 2.0 :D

Bored out M42 (86.4x81) should be exactly 1.9L Nice and oversquare too.

[nickmpower]

so is it real easy to switch between the maps?

and i dont think i want it so bored with boost!!!