Lotus Europa Race Car Collection

[Mecky]

Hi guys,

there seems to come up a small group of Europa drivers in this forum, who uses these little cars for racing. And it does not matter whether it is autocross, hillclimb, rallye or circuit and also if more modern changes are allowed or the car has to be prepared in accordance with a historic reglement...

This is a try to create a kind of archive here, where these Europa drivers have the chance to show their cars and modifications in detail and tell about the technical data. Whereas the thread "Experieces in Racing an Europa" is more about telling stories of races, which were entered, and results and knowledge, which was achieved while racing.

To start it up, I will give a short conclusion of our Lotus Europa S2 Type 54, which is prepared in accordance with FIA Appendix K and raced in the Two-Seater Racing Car class up to 2000 ccm displacement.

Displacement: 1565 ccm
Power: 158 HP / 117 kW
Torque: 181 Nm / 134 lbf ft
Weight: 669 kg / 1475 lbs
Height: 7 cm / 2,76 in
Tank Capicity: 80 litres
0 - 100 km/h / 0 - 62 mp/h: 4,8 s
Max. Speed: 230 km/h / 144 mp/h
Rims: front: 8x13", rear: 9x13"
Tyres: front: 215/50/13, rear: 235/45/13; Kumho Semislicks
Brakes: front: disc, rear: drum

Modifications:
 - Aluminium air deflector leading to the radiator
 - air-hoses for front brake cooling
 - completely removeable front bonnet
 - two circle braking system with steel-flex brake lines and adjustable brake balance between front and rear
 - master cylinders: front: 0,7", rear: 0,625"
 - heater removed
 - whole interiour removed except the dashboard
 - passenger seat replaced by a go-kart-seat
 - racing driver seat
 - roll cage
 - fire extinguisher
 - emergency stop switch (can be operated from outside the car)
 - two 45 Weber DCOE twin-carburettors
 - lexan door- and rear-windows
 - fan-type exhaust manifold
 - Renault 807 engine with crossflow-head
 - racing rods and pistons
 - lighter crank shaft
 - racing cam shaft
 - sport clutch
 - two aluminium fuel tanks
 - three fuel pumps
 - fuel pressure regulator
 - fuel catch-tank (1 litre)
 - oil catch-tank (1 litre)
 - removed rear boot
 - racing shocks and springs

I think that's about it. I hope you like the idea of this thread and take part.

Best regards

Stefan

[A.Schmidt-Ohren]

Hi Mecky

  (many thanks stefan)


this is mine

of course, FIA Appendix "K" and road legal for saison 2014 

[Valerio Leone]

Hey Mecky,

your data is impressive!
this shows that if Jean Redele hadn't stopped Renault from supplying (updated) engines back then it wouldn't be a fuss aganist Apline.

 

Hey Mr. Schmidt, bon courage!!

[Jas]

Hello Mecky

Great topic.
Could you please give us some more details regarding your suspension, like spring rates and length and also your dampers make and model?

/Jannik

[Mecky]

Hello Mecky

Great topic.
Could you please give us some more details regarding your suspension, like spring rates and length and also your dampers make and model?

/Jannik

Hi Jannik,

I'll try to look it up at the next weekend.

Best regards

Stefan

[Mecky]

Hi Jannik,

the shocks are made by Protech (400 series, 2,25id). The length is 11" (front) and 16,5" (rear). Spring rates: 225 lbs/in (front) and 250 lbs/in (rear).

Best regards

Stefan

[Serge]

Hi Jannik,

the shocks are made by Protech (400 series, 2,25id). The length is 11" (front) and 16,5" (rear). Spring rates: 225 lbs/in (front) and 250 lbs/in (rear).

Best regards

Stefan

Stefan,

Do those springrates feel OK on track? Because that's not a "normal" setup for a europa. I would guess that a good starting point would be 240/190 F/R, maybe a bit stiffer in the rear if you have bigger tyres on the rear like you. But it would be more logical to have a higher spring rate in the front than in the rear. Have you done much testing with different spring rates?


Kind regards,

Serge

[Mecky]

Serge,

the rates feel very good. We had softer ones until 2012, but there was so much body roll while cornering. Now it is much better. But we did not test any other rates.

Why is it not normal? In stock the Europa has softer springs in front than rear. The front is much lighter, so why should you choose stiffer springs in front? With very stiff springs in front, the nose will not go down so far while braking. But you need the weight transfer to the front, so that the front breaks will not block so early. Especially in wet conditions this is very very important.

Best regards

Stefan

P.S.: The first picture is from 2011 and the second one from 2012 with new suspension. Same track, same corner.

[EuropaTC]

Hi folks,

Ok, I'm not a race guy (and never likely to be) but I am interested in this debate as I'm trying to work out what to do with my car for next summer as far as springs & dampers are concerned.

Stefan, the standard springs (TC) are stronger at the front, 116lbs/ins & 75lbs at the rear, but of course there's more suspension leverage at the front so the effective rate drops.

Most of the info I've gathered point to stiffer front springs than rear although your reasoning seems very logical and is consistent with the TC Race Preparation booklet from Colin Ham, who used 180lbs front & 200lbs rear.    It's also consistent with the Elise (my S1 has 240lbs front, 280lbs rear IIRC) although I must admit I haven't worked out the changes due to geometry on that car. But it's possibly even lighter at the front than the Europa at 40/60 distribution and similar road weights.

As a rookie at this aspect of the car I do find the game confusing, hence I appreciate you guys sharing such info.

Brian

ps - Stefan, did you stay with 2.25" spring diameters for both front & rear ? I find the smaller 1.9" springs a real nuisance to compress but the slightly larger ones fit my tools much better and would prefer to use them all round if possible.

[Serge]

Original spring rates for an S2 are:

100 lbs.in. (1.15 kg.m.) in the front

72 lbs.in. (.83 kg.m.) in the rear

and most of the europa people (including Jay Mitchell who has autocrossed his car extensively and has tested a lot of springs) are keeping this F/R ratio in the spring rates.

However I do understand the logic behind your choice. I would like to know what Valerio is running as wel, just to compare notes.


Kind regards,

Serge

[Mecky]

Hi Brian,

Stefan, the standard springs (TC) are stronger at the front, 116lbs/ins & 75lbs at the rear, but of course there's more suspension leverage at the front so the effective rate drops.

That surprises me.

ps - Stefan, did you stay with 2.25" spring diameters for both front & rear ? I find the smaller 1.9" springs a real nuisance to compress but the slightly larger ones fit my tools much better and would prefer to use them all round if possible.

Yes, 2,25 all around.

Best regards

Stefan

[EuropaTC]

Thanks Stefan, although it's one of those silly things I feel happier working with slightly larger diameter springs providing there's no significant trade-off in performance. I've also looked at the pro-tech site and SJS, their UK supplier and they look well made units.

The OEM spring rates always puzzled me as the first impression seemed to be the wrong way about.  But I used some formula from Alan Staniforth's book on suspension (dated now but from the era of these cars) and weighing what I could then making some assumptions for what I couldn't, I found that the spring pre-loads after allowing for suspension leverages came in at 427F, 417R. Of course that can be well out with the guesswork, but it did slow me down a bit as the maths indicate it balances well.

I've read a lot of Jay Mitchell's postings and there's no doubt he is good at the game. Personally I like the way he goes about it.  But regarding his choice of spring rates you've got to remember that he's specifically aiming at autocross and using the OEM suspension layouts. I suspect once you change the physical suspension design/dimensions as you've done, all bets are off as to what previous recommendations will work and the best way forwards is practical experience (and lap times    )

I'm currently going through the knowledgebase and sifting out various combinations that have been discussed. If there's any interest I'll post the results here when I think I've got it all down.

Brian

[HealeyBN7]

Brian,
I am very interested in spring rates, so please do post what you learn.

In my Zetec S2 I started with Dave Bean's recommendation of front  2"x10x110 with  2" x 13.5 x 115 on the rears. All are on adjustable AVOs. The front setup far too light and would not keep the car off the bump stops.

Replaced the fronts with 2"x 10 x160... With this set I was unable to lower the front to a non Federal height, so I ordered 2" x 9 x 160, but as you can imagine the same spring force with a lower height softened the front too much and I would bottom on road imperfections.   With a passenger it was frequent.

This led me to my current setup which is still not ideal.  I cut the 2"x 10 x160 to 8" effectively raising the spring rate by 20% to 192.   it is better.  I fell that I can go even higher.  Perhaps to 220 without any drawbacks.  With no changes to my rear setup you can see that I am radically out of balance 192 front/115 rear. 

I have a new larger front sway bar to install and I would like to get my springs sorted this winter, so I'll be watching this thread with interest!

Thanks.  Great thread.
Dean 

[Bainford]

I'm currently going through the knowledgebase and sifting out various combinations that have been discussed. If there's any interest I'll post the results here when I think I've got it all down.

Brian

I'm very interested in hearing what you've learned regarding spring rates. My car is still wearing its original springs and dampers so thoughts of replacing these are on my mind. I haven't looked too deep into this yet but it's quite high on my 'must do' list of Europa improvements. Cheers

[EuropaTC]

I'll be happy to post up what I find as long as you guys remember I really don't know enough about this aspect of our cars, this will just be data for interpretation & background.  I'll try to collate it for the weekend.

One thing that does stick out though is a phrase from one of Jay Mitchell's posts - "getting recommendations is easy, getting ones that work less so" (or something like that). There's a whole range from the standard 100/116 of the S2/TC to 750lbs/ins for a track car. I can't even imagine what that's like on the roads !

Brian