e30 m52 s14 s50 weight comparisons

[matt]

How are your front tire temps? Even across the tread yet?

I would suggest a swap to Races and even more front camber.

[static]

i also still run narrow-ish tires (205/50/16 hankook rs2s) would that be a factor?
never measured the temps.

this is a daily, springs/shocks are borderline stiff for this duty. maybe i should look into sways

[matt]

That's plenty of tire. More pressure at the front would help, so would sway bars.

[e30pq]

This is the Bimmerforums thread on the M42 turbo build.

http://forums.bimmerforums.com/forum/showthread.php?t=698624

Rob and I own the car. We did most of the work on the car ourselves except the cage and some of the custom engine build pieces like the turbo manifold and the intake. We also got some help with the custom ECU.

I helped a little on the M42 engine project but Rob did most of the work on the engine project.

We dynoed the car on Tuesday. The results are at the end of the thread.

We are going out to Willow Springs on Sunday to try the car out with the new motor.

We should have some in car video footage.

Paul Q

[static]

This is the Bimmerforums thread on the M42 turbo build.

http://forums.bimmerforums.com/forum/showthread.php?t=698624

Rob and I own the car. We did most of the work on the car ourselves except the cage and some of the custom engine build pieces like the turbo manifold and the intake. We also got some help with the custom ECU.

I helped a little on the M42 engine project but Rob did most of the work on the engine project.

We dynoed the car on Tuesday. The results are at the end of the thread.

We are going out to Willow Springs on Sunday to try the car out with the new motor.

We should have some in car video footage.

Paul Q

very impressive! i've been toying with an idea of eventually ditching a heavy chunk of an s50 for a turbo-4.
I however agree with a guy's post on bf.c about the shape of the torque curve.
I'd be much more content with a relatively constant torque of about 250lb/ft over at least 3krpm interval (say 3 to 6krpm)
Please do update us as improvements are made.
BTW can you share at least a general info on what went into the engine build? How little can one get away with while pushing 15psi on an m42?

Alex

[e30pq]

The engine under 2 liter with custom pistons and no head work.

As you know there are plenty of things that you need to spend money on like the custom turbo exhaust manifold, custom intake, programable ECU... it all adds up and you always have a list of things you would like to improve in the future.

The good part is that these motors are less expensive than S14's.

I can however say that we were hoping for 350 hp max and on the first tune we ended up with 283 hp at the rear wheels which equates to about 333 hp at the flywheel.

We also think that with more tuning we can get a flatter torque curve.

Paul Q

[BingM3]

If you think about it:

Approximates:
E30M3 weighs about 2,735 lbs
E36M3 weighs about 3,175 lbs

Removed S14 engine/4 cyl tranny
-234 lbs
-150 lbs tranny?
= 2,351 lbs

Conversion start weight
2,351 lbs
+ 333 lbs S50 engine
+ 200 lbs 6 cyl tranny?
= 2,884 lbs

E30M3 = approx end weight with S50 engine/tranny is 149 lbs more @ 2,884 lbs but 291 lbs less than an E36M3

I think this figures why 0-60 and 1/4 runs are just about the same as an E36M3, better perhaps to a slim degree?

E36 M3 runs 6.0 secs 0-60 and 1/4 of 14.6 factory specs
On my s50, I have done G-Tech Pro and had best of 5.96 0-60 and 1/4 of 14.46 with 17's Motorsport E36 rims, I hope to try 15's and see the outcome - of course with other mods, better numbers are expected but this is from stock on stock comparison...
Launching the E30 aggressively with an S50/52 is harder on 1st and 2nd (tire spin) maybe that's why.

Anyone care to comment?

[gobuffs]

Anyone care to comment?

Yeah...your weights are way off. The difference in weight between a S14 an S50 is about 50 kilos (110 pounds). The S14 tranny is nowhere near 150 pounds- 60 tops. The 6 speed tranny is closer to 100.

Getting an E30 M3 down to 2351 by just removing the engine and tranny? I doubt it. 2735 as starting sounds a bit low.

[BingM3]

Yeah...your weights are way off. The difference in weight between a S14 an S50 is about 50 kilos (110 pounds). The S14 tranny is nowhere near 150 pounds- 60 tops. The 6 speed tranny is closer to 100.

Getting an E30 M3 down to 2351 by just removing the engine and tranny? I doubt it. 2735 as starting sounds a bit low.

S14 - 234 lbs and S50 333 lbs....weight I stated was right = 100 lbs

As for the M3 weight, I got it from the M registry...tranny I was not sure...but a differential alone weighs about 70 lbs, a tranny is 60 lbs???

[dark89e30]

60# trans! No way! And I'm pretty sure even the diff weighs a bit more than 70#. I'd love to be corrected.

[PiercedE30]

No, actually I believe the 260 tranny only weighs about 50-60 lbs. That thing is light.

[BingM3]

When I shipped my S14 motor/tranny to TX via freight carrier, weight was rated approx 375 lbs with crate

[gobuffs]

A diff doesn't weigh 70# and the tranny is lighter than you would expect. realoem doesn't show part weights, but the ETK does. I don't have an ETK installed here at work.

[BingM3]

I sold on ebay a diff and it weighed 68 lbs after weighing at Staples UPS drop-off location.

[static]

That's plenty of tire. More pressure at the front would help, so would sway bars.

just wanted to chime in with my fix to the gross understeer i used to have with the car: the solution was changing tire pressure as matt suggested, but the opposite way..
going from my regular 38 front , 35 rear, i changed to 32 both front and rear and that made all the difference in the world! Minimal understeer that remained was easily dealt with a bit of throttle.

it was a good track day.