Ohio Track Build

[robinlarry]

I've been modifying my 1991 Federal m100 for the track for the last year plus and thought some of you might find it interesting. This is the work completed so far (except for the wiring which I'm finishing now).

Callahan short shift kit.
Rebuilt turbo and ported wastegate
Eliminated two cats and added Piper 2 1/2 inch stainless exhaust
Cleaned and balanced injectors
Installed Quaife differential
Delete EGR system
Installed new racing clutch and aluminum flywheel
Installed front Wilwood brakes with new pads
Installed all new wheel bearings and front hubs
Sandblasted and repainted suspension with all new bolts
Removed carpets, sound insulation, spare, windshield washer tank, interior pieces.
Removed dash
Removed windows and motors
Removed door covers
Removed all HVAC
Installed new track tires
Installed polyurethane bushings
Installed Europa roll bar
Installed new overflow bottle
Installed Simon carbon fiber hardtop
Removed soft top and frame
Installed Samco hoses
Installed Nitron coilovers
Installed new Coolex aluminum radiator
Installed new stainless front brake lines
Safety tied front disks
Corner balanced (50/50 cross weight with weights at 789/752/412/375 for LHF/RHF/LHR/RHR.
New "track" alignment. Sorry. I don't have details on what the shop did .
Revising main wire harness to eliminate unnecessary wires. I've used a spare harness to lengthen certain wires with matching colored lines. Also replaced plugs with Deutsch waterproof connectors. When finished, only fuse and relay boxes should be visible on passenger floor well.
Revised front cross bar to eliminate unnecessary brackets
Remove throttle body coolant line
Remove supplemental water pump with associated water lines.

Still to be done:

Install Tillett racing seats (-30# total)
Modify turbo to hybrid unit (265 hp)
Fabricate new dash / door covers in style of earlier Elans.
Install smaller battery. (-30#)

[robinlarry]

BTW, pretty much everything I've done to modify the car can be undone and the car returned to original. I also have an unmodified main wiring harness.

[Fredjohn]

Nice work for track use. However, given the auxiliary water pump's function, ie to allow turbo to cool slowly and progressively after hot running, but with the engine off, I would seriously suggest you refit it!
You are after all running 250+hp, on track at higher than regular road revs for sustained periods. The electric pump works in the opposite direction to the mechanical pump, so is never in operation when driving.
Good luck with your project!

[Tuga2112]

ahh but John. that goes against the mantra to "add lightness" !!

and yes. i do agree. this is in fact. one of the few cases where that pump will be likely to be usefull, (very usefull)

and... im looking forward to reading details about the work. particularly with "how" you tackled the tasks, and which ones are harder to overcome etc

[dapinky]

As someone who has bult and raced a few various cars in the past, it looks like a good and comprehensive list to me!

Going against the flow of comments, I can see why removal of the aux water pump was chosen..... and I know why Joao and John both caution against it..... but as long as the risk is understood, then the advantage should weigh in your favour.

The whole point (of the pump) is to stop the turbo from getting too hot immediately after turning off the engine, following a 'spirited' drive - but it was fitted to road-going cars where they could be driven by any old geezer with a few quid to spend, and little understanding of the (quite new at the time) concept of turbochargers.

These days, there is far more knowledge about them, and they are fitted to a high percentage of cars coming off the production lines.

Everyone knows that it is bad to turn off an engine which is running hot (unless it is gaining temp and cannot be controlled.... maybe a coolant failure or whatever!), and most understand that the turbo will heat up the oil inside it until it flows away, evaporates or other wise buggers off and leave the bearings unlubricated at the next initial start-up. This has been sorted by clever blokes in sheds over the years, and is not an issue with more modern designs.

Lotus solved the problem with their own clever engineering in a simple-yet-complex system designed for the "weekend warriors" who would rant up the local 'B' roads to the cafe and turn off the engine whilst it sits there ticking like a clock (even if those people didn't buy the cars, the system was build for them!). It wasn't part of the original design brief, and only made an appearance on the PP car(s) during the PP stage of development.

Anyway, back to the point for removal - ANY track session is designed to allow for a 'warm-up' lap and a 'cool-down' lap - this allows for the engine (specifically the turbo and exhaust systems) to cool down before returning to the paddock, and also to allow the brakes to cool down with airflow and non-friction application.

In the past I have seen cars come straight from a 'hot' run into a paddock and then set the grass on fire underneath it.... nearly always at a track day organised by some of the 'Max Power' type of boy-racer magazines...... I have NEVER seen it at a proper race meet or organised track day - because they tend to attract educated people, and/or those willing to follow instructions.

There is always the "what if...." situation where the car is forced to stop during a hot lap.... either due to mechanical failure of track conditions. If it is your own mechanical failure, then so be it - a blown tyre would mean that the car has to stop, but the engine can still be run for a short while (unless unsafe and/or instructed by a marshal)..... and a blown engine would mean that the turbo is probably well down the list of worries at that time!

The only situation I can see where the reverse pump may actually help is if the oil-line to the cooler lets go and so the engine needs an immediate shut-down.... possibly when driving at 7000rpm.... (but how many people on a track will be able to do that expeditiously???) to keep some coolant flowing - and even then, it will only work with the ignition off, which would somewhat make life interesting if you are coasting to a halt with the steering lock on (which I presume is being or has been removed from a track-car anyway).

Obviously, any situation where there is a catastrophic loss of coolant would make no difference if there is a pump or not, when it is just spinning in air.

Personally, I'd take it out and fit a timer to allow the fans to run on for 60 seconds or so after turning off the ignition - but if every last # of weight isn't important - leave it alone.

[robinlarry]

Dapinky is correct. You would not immediately turn off your engine after coming off track.

Removing the pump also helps to eliminate some of the clutter around the engine. Can I reroute those two large plugs attached to the coolant bottle? (Yes) Let's also eliminate the EGR line and associated wires. (done). And the two blue plugs associated with the gas tank pollution devices. Do you really need wiper speed adjustment? Wouldn't an on/off switch for a simple relay be sufficient?

Most difficult task so far has been revising the wiring. Once you get past the decisions regarding what to keep and to eliminate, you have to decide how to group and modify wires to get them where you want them - in my case, all on the right hand passenger side. (Fed car). Everything you need is in the electric manual, but it's still very time consuming. The spare harnesses were very useful.

If I were to do this again, I would remove all the wiring and purchase a stand alone computer with wiring included for signals, lights, etc. That will come with the hybrid turbo in the future.

[TorqueHorse]

Very exciting to see you are undertaking this work! Sounds like an awesome build.

[robinlarry]

Safety always first.

[robinlarry]

Quick release 26r style steering wheel

Quick release 26R style steering wheel

[robinlarry]

M100 with hardtop. Hardtop and roll bar allow me to run/instruct with most groups.

[FunElan]

I'll be most curious how it performs on track!

[robinlarry]

I had the car at MidOhio Race Track in May and it handled great. Unfortunately the transmission stopped working after two sessions so I had to call it quits for the weekend. It turned out that the tiny pin to adjust throw in John Callahan's short shift kit had moved out of position so it was an easy fix.

BTW, the Nitron shocks and springs were an expensive choice but really do a great job on track.

I just ordered a Tillett B10 seat. There are cheaper seats available here in the States, but I want to stick with the British manufacturer. The B10 is an interesting design in that it allows you to use a three-piece conventional seat belt or a racing harness. The Porsche club now requires a HANS device (which I have) if you use a racing harness. To avoid the inconvenience, I plan to keep the original seat belts.

[robinlarry]

Tillett seat fits perfectly and mounts using existing holes in floor!

[RonR]

Looking good there!

Small World - Steve Tillett's a member of our local Lotus group.
Another member fitted a Tillett seat to his track-day Elise Cup. He's no spring chicken but reckons it was worth 1-2 seconds a lap!

[robinlarry]

I figure about a 30 pound difference with both Tillett seats. Add that to 30 pounds for a small battery and I should be around 2110 with roll bar and hard top.

[robinlarry]

Relays and fuses moved from left side to right side.

[robinlarry]

Finally received my second Tillett seat. Just waiting for the mounting bracket. I'm using the original slider mechanism with a few unnecessary brackets removed. Getting closer to putting it on the track.