1991 BMW E30 318is: Rally Build

formyhealth said:

In reply to formyhealth :

I did it.

I bought a 2016 2.0 Ecoboost with 9,000 miles. I am looking into Bell housing options and am leaning towards the 6 speed t56 transmission. Just need to fab mounts, get in contact with dss to get a custom driveshaft, buy the plug and play harness from Ford racing and we should be in business. 

 

This is relevant to my interests. Though I've been considering trying to drop a Nissan VQ30/35 into mine if possible. I'll definitely be following to see how you address the bellhousing, etc. 

One thing to check - some rally organizations require a waiver to run a non-same-brand engine (i.e. Ford in a BMW). I think they're pretty easy to get these days, but I know in the past a fwe people have had issues with non-marque swaps in rally cars.

formyhealth said:

In reply to ValourUnbound :

Regional group 5 ARA looks open too (unrestricted engines etc.) I'm hoping for Tour De Forest in October, my understanding is that as a first time stage rally the car has to be n/a so I am not sure about this and how I will be able to proceed, I'll need to make some phone calls.

Group 2 vs. Group 5 hardly matters these days anyhow. At least here in the East G2 tends to be overall faster than G5 anyhow, with all the small-displacement FWD things out there these days making good power. IIRC in the last few rallies we've run, G2 cars have finished on the overall 2WD podiums rather than G5 cars. Maybe out west different since I think some of your rallies are more wide-open in some cases.

In reply to irish44j :

Are you talking about the M42?

I ended up buying a 9,000 mile 2.0l ecoboost that I am going to install :)

formyhealth said:

In reply to ValourUnbound :

Regional group 5 ARA looks open too (unrestricted engines etc.) I'm hoping for Tour De Forest in October, my understanding is that as a first time stage rally the car has to be n/a so I am not sure about this and how I will be able to proceed, I'll need to make some phone calls.

I think the 2.0 ecoboost could make a great rally power plant. I don't think the t56 is the trans you want for multiple reasons, though. You probably want either an NC Miata or ranger 2.3 trans. Both will bolt to the ecoboost block. For staying NA, you can pick up a very inexpensive na "2.5" duratec from a fusion to start, them switch to the ecoboost. It's actually a hair under 2500cc which I think keeps you in light or whatever.

In reply to bluej :

the NC Miata transmission 100% will eat itself with 350 ft/lbs of torque, not through anecdotal evidence but from speaking with someone who has gone through a few of them already. The 5 speed ranger may be beefier, but haven't looked into it to much. I am trying to verify if the mt-82 from the 2.3 ecoboost mustang will work, and so far it's looking promising.

That's a good idea on the n/a 2.5 duratec as long as it shares the same mounts, then it could be swappable.

That's a lot of torque to put through two wheels on a non-consistent surface.  I'll let others weigh in with stage rally experience, but for rallyx, you're struggling to put down much more than 200whp in most RWD configurations. Something to check into anyway, since my experience is only with rallyx. I mention it to consider when you plan your tuning and also for drivetrain choices.

The 2.3 trans from the mustang sounds like a good avenue if the costs are reasonable.

In reply to bluej :

There were a couple of high horsepower rwd cars at Oregon Trail Rally this year and I see it as a fun experience, if I get really seriously into it then I'll 100% go awd and all that jazz.

if the mustang trans works out it'll save me about $600 or the cost of the bell housing adapter that I would need to get if I wanted to go t56 or the like. It's about $300 more than a NC Miata trans so if it fits I'll consider it money well spent.

My rally XR4Ti has somewhere in the neighborhood of 230 hp/300 ft-lbs of torque- it can put the power down, and more would still be usable, but it's probably not really necessary.  There is a drastic increase in how fast the rear tires wear compared to my old RX7 (150 hp, not much torque) which seems disproportionate with the increase in acceleration.  Some of that may be because the car is heavier as well.

In reply to irish44j :

Another transmission option that should bolt up directly after swapping to the 2.3 pan is the getrag mt-82 transmissions from the ecoboost/v8 mustangs. 

In reply to ¯\_(ツ)_/¯ :

A heavier car would definitely wear the tires faster but I'm sure the increase in torque exacerbates that as well.

In reply to formyhealth :

Sure, I guess what I'm trying to say is that there seem to be diminishing returns- past a certain point you're eating tires X% faster in order to have your stage times be way less than X% quicker.  That point probably depends on car weight, surface, rear suspension design, and a whole bunch of other stuff.  2wd open class results seem to suggest that it's somewhere in the 200-300hp range for most cars and drivers.  If I were building another 2wd car from scratch right now I'd be aiming for under 2500lbs and just over 200hp, N/A for reliability.

¯\_(ツ)_/¯ said:

My rally XR4Ti has somewhere in the neighborhood of 230 hp/300 ft-lbs of torque- it can put the power down, and more would still be usable, but it's probably not really necessary.  There is a drastic increase in how fast the rear tires wear compared to my old RX7 (150 hp, not much torque) which seems disproportionate with the increase in acceleration.  Some of that may be because the car is heavier as well.

Using jumps to adjust the rear camber dosent help your tire wear either 

In reply to Gaunt596 :

That particular instance of mid-stage geometric reengineering is being excluded from the data set 

We have a lincoln MKC w/ the 2.0 and its 240/270 are very responsive. I flat tow my rallyx e30 with it. 

The low end torque of the 2.0 ecoboost would be a plus over an NA drivetrain, you just might not need to turn the wick on it all the way up.  Which helps with reliability as well like Chris (screw your shruggy shoulder wingdings screenname :-p) was alluding to.

formyhealth said:

In reply to irish44j :

Are you talking about the M42?

 

I ended up buying a 9,000 mile 2.0l ecoboost that I am going to install :)

yeah, I posted that before I got to your later post, lol...

In reply to irish44j :

gotcha!

Well for reference I will be keeping the m42 as well

It seems like, even though more expensive, that a tremec t56 may be a better choice due to size as well as durability. I am not liking the things I am reading about the getrag mt-82 when you throw power or high rpm shifts at them.

Little progress report, the engine showed up and is starting to get prepped.

Also, fixed the frame issue by turning an new insert and welding it in.

She runs! (Well with the old M42)

I got out there and finished installing the subframe, steering column and bent up the stock power steering lines to fit the z3 rack. 

The rear end is noisy, exacerbated by the poly differential mounts I'm sure. Also needs an alignment as the string alignment isn't perfect nor did I try to make it so.

On a bummer note there seems to be a short or power drain somewhere as my brand new battery was dead after 4 days, for the meantime I'll keep the charger on it.

Can anyone give me some possible places where there could be a power drain?

To update last night's post, I was able to find the power drain today, it was fuse #21 which I don't need anyway since my OBC is non func, no stereo and who needs a glove box light? Anyway that's happy and my over all current draw when key is off is around 2-3 mA which is less than 6 so I'm pleased.

also check the electric antenna motor. That's where my power drain was from. Motor didn't work, but was sucking power nonetheless.

In reply to irish44j :

It was electrically disconnected and made no change, but that was something I did check.

So.. I changed my mind again and am going with the 2.3l mustang transmission, found one local with only 6k miles on it, will be here tomorrow! Also, the Ford performance wiring pack and PCM shipped, and the RWD engine conversion kit is not far behind. Things left to purchase:

• flywheel, clutch and pressure plate (from a 2015+ 2.3l Mustang)
• Fuel pressure regulator to dial pressure back to 55 psi at the manifold
• custom clutch line
• custom driveshaft
• tubing and bushings to fab up motor mounts and transmission mounts
• Probably a new inlet air temp sensor (mine is broken)
• Probably a new radiator, hopefully with inlet and outlet both on the drivers side

Should be getting close!

Transmission has arrived:

It's been a while, so to recap:

Got a shiny ass clutch

Pulled the old M42

Test fit the new EcoBoost

Got some bling

Pulled a bunch of weight out of the car!

and then started the process of fixing the cracked dash

I just dropped the rear sump oil pan off at my machinists shop to have him turn it into a front sump, that way we clear the subframe and don't have to go about hacking up the hood, or at least that's the plan for now.