E30sho's SHO powered BMW E30

[e30sho]

Hi All,

My project is a mash-up of a 1985 BMW E30 (318i) and a 1992 Ford Taurus SHO 5spd. The design goal is for a fun street legal track day car with a target budget of $7000. I’m working from Kurt’s book for general direction but obviously skipping the full tube frame and composite body steps. I chose this route because I’ve always wanted a) unique car, b) a BMW and c) a mid engine car. The SHO motor is 3.0L but after I get the car running and sorted I’ll be dropping in a 3.2L.

I found the BMW with a worn out drivetrain for $500. I got a pretty worn out Taurus for $1000. Gutting the BMW was pretty quick, easy and fun. Carefully stripping the drivetrain and wiring harness out of the FWD Taurus was no fun. Both cars were greasy messes and I’m glad that’s behind me.

My car will have a full cage, and be partial tube frame from the main hoop back since I had to cut the frame rails out to fit the motor. Right now I’ve got the motor in place in the car, the main hoop in place, the sho shifter mounted, and a generic summit radiator installed in front (with the sho fan). I’ve got alignment strings around the car and the back wheels propped in place. I'm currently working on the rear suspension fabrication and the motor mounts.

Other random details:

Front tires: Toyo 205/50-15 on 15x7’s
Rear tires: Toyo 225/50-15 on 15x8’s
Miata spindles front and rear.
Miata 1.8L brakes up front
Miata 1.6L front brakes on the Miata rear hubs (if I can get that to work)

Peter

[violentblue]

Not quite a 7, but there will be some interesting crossover material.

stickied

[sodamninsane]

so your picture begs the question......... is it level?



Thats an interesting choice of pieces for the rear that you've made... why not just use the factory front spindles from the SHO? Even if they're struts you can still make it work.

Anyway, good luck! Looks like a fun project.

[e30sho]

Not quite a 7, but there will be some interesting crossover material.

And that’s why I appreciate so much you guys sharing your forum with me!

so your picture begs the question......... is it level?
<snip>
why not just use the factory front spindles from the SHO?

Ha. Yea it’s level. Both axially and whatever the complement of that is. And yes, so is the car. I put the car on HF jackstands and then leveled those up with thin steel shims until the pinch welds on the bottom of the BMW were all level. Everything is getting installed level to those and square to a string line down the center of the car.

There are many reasons I chose to use the Miata rear spindles:

* The sho was 3500# and my 332ls will be 2500# so the sho brakes would be overkill.
* I needed to shorten the sho axles anyway or the whole thing would have looked goofy wide so there’s no $ savings there.
* The sho front stuts were shot and I would have needed new springs anyway so there’s no $ savings there either.
* Because the sho struts are huge compared to coilovers so fitment would have been more of a challenge and the rear track would have to be wider.
* Because I drove a Spec Miata race car for 3 years and I’m spoiled by *great* handling.
* Because I want a short/long A-arm suspension.
* Because I want to experience all the fab work.
* Because the sho hubs weigh more than a tungsten brick sh!thouse.

Peter

[violentblue]

Looks like you'd have enough room to do an unequal length a-arm setup in the back, but with the motor mounted transversly the length of them will be less than ideal, But you should be able to improve handling greatly over a solid axle or strut suspension.

[sodamninsane]

Looks like you'd have enough room to do an unequal length a-arm setup in the back, but with the motor mounted transversly the length of them will be less than ideal, But you should be able to improve handling greatly over a solid axle or strut suspension.

depends on the box.. could make the arms wide enough on the top to fit around the engine... then you're free to do whatever you want.

lowers shouldn't be a problem though.

[e30sho]

Cut fender out for larger tires. I’ll probably add some simple fender flairs to clean this up. The simple tube base under the tire positions the hub center at ride height (taking into account static radius). The string around the tire is there to hold the hub upright during mock up.

[e30sho]

Recent progress for motor mounts and rear inboard pickup points. Next will be rear framework: Since the frame rails are cut I need to secure the rear of the car to the front. There will be two 1.75x.095 DOM bars on each side of the motor: a low one coming back from the bottom of the main hoop and a high one arcing down over the motor creating the pickup points for the coil over shocks/springs.

Peter

[Blackbird]

I'm assuming that there will be a full firewall with a window between the passenger compartment and the new engine bay, right?

Looks cool, keep it up!

Moti

[e30sho]

I'm assuming that there will be a full firewall with a window between the passenger compartment and the new engine bay, right?

Good question. The answer is Yes and then some… I will add an SCCA legal scatter shield around the tx to prevent a clutch/pressure plate failure from killing me. I am also planning on incorporating some sort of tube structure that ties together the main hoop and the tubes in front of the motor to create a motor catcher such that if I ever hit something hard head-on the motor will be very unlikely to make it to the front seats. I’m a volunteer fire fighter and I’ve seen enough wrecks that I think this is necessary.

thanks for the kind words and thanks for asking,
Peter

[Blackbird]

Good to know you've been thinking about those.

Here's an idea (if you haven't thought about it yet) - replace the existing rear window with a vented Lexan piece a-la Ferrari F40.
Easy to make, saves weight and improves the cooling.



Moti

[JackMcCornack]

This is an interesting and highly imaginative build, and I'm enjoying following its progress. It would be easier to find, I think, if it was on the <Non-traditional Build> forum with the other middies. I sure think it qualifies as non-traditional.

The scattershield is a good point. I hadn't thought of it myself. Does the At-om have anything there? La Bala? A transverse middy clutch failure would go through the back of the driver like a light saber (BTW, this is why I thought this should be posted among the non-trads, since your car isn't the only middy that ought to address this topic).

[e30sho]

Moti,

good idea. I hadn't thought of it. I'm planning about drilling several holes in the back of the trunk much like the Ferrari 260 challenge cars. I heard they dropped engine bay temps 20 degrees by doing that.

Jack,

I don't know what other transverse middy guys have done but it's a good question. As far as moving the topic I'll leave that up to the administrators. I'm just happy to be here, anywhere.

If anyone wants to look it up, the SCCA scattershield specs are online at scca.com in the GCR. Basically it’s:

Minimum material specifications are:
.125 inch SAE 4130 alloy steel
.250 inch mild steel plate
.250 inch aluminum alloy
NHRA or SFI approved flexible shields.

Peter

[Blackbird]

What about a kevlar blanket?
Very strong and super light.

Moti

[e30sho]

The nhra guys use Kevlar blankets. On a road race car I think you might have issues trapping a lot of heat in the transmission. Plus, they aint’ cheap. I built a scatter shield for an SCCA AS mustang out of ¼” diamond plate aluminum which I bought scrap for something like $15. Below is a pic of it before final welding. That scatter shield bolts to the top & driver’s side of the trans tunnel. I plan to do something similar for my car except the shield will cover the top and front of the tranny.

Peter