[elise/europa]

Another threat about a personal car. The mean reason for that threat is to give feed-back and help to peoples looking for similar mods. It can be helpful for many of us, as well as I am quite often looking
about experience from other car owner.

I am happy to show the result of a long run evolution of my car. I purchased the car in 2006. The car is in constant evolution since then. I am open to have this threat as an open discussion about solutions I did.
First: the car like it was: The car is used on the track and street since the beginning. The engine 2ZZ was pimped up with a Katana, after with a Rev 300 with a modified block, and after a Rev 400. Many parts were modified as the suspension, brake etc. For me, the 2ZZ engine is a fragile engine, and I spend a lot of money to have it as reliable as possible. Between 2015-2016, I stopped to use the car on the track because it was too much fragile.

2017 turnover: The car was fitted with a K20 built engine for a Turbo set-up. The goal was to have a faster car than ever, and more reliable. The car is used mainly on high speed race track close to Montreal, like Mont-Tremblant and Calabogie. And of course, used like a street car. The file on attachment shows the complete parts list of the car. The engine, with 396 whp is quite powerful, and the turbo give a big torque boost with a kind of unpredictable. It is not as good power delivery than supercharge. As a prototype, the car ran on track 3 times during summer 2017 with average result. Burn one turbo outlet hose after 15 minutes on track... second trial, I busted one rear axle. And the third trackday was good, ans since I was very rusty driver, I just meet my lap time of 1:48. Then, I was not faster than 3 years before, but equal with a relax rusty attitude. Not bad after all. The max speed on Mont-Tremblant straight line is now 230 and it was 212 3 years ago.

2018 improvement:
- Improving the throttle body opening with a drive by cam throttle body. With the turbo, the power is
not proportional to the TB opening. The cam should help to obtain a more relax power delivery with
small pedal movement.

- The car will be equipped with a Traction control from Hondata. I don’t know if it will work great, but
not expensive to purchase, why not, Off mode still a possibility if I don’t like it. The TC will use to output from the ABS controller.

- Return of the ABS. The ABS was removed from the car in 2008. The car is now very very fast, and I start to be quite old... I decided to put back an ABS, but a racing proposition, the Bosch clubsport M5 ABS set for racing application. Expensive of course, but I expect to be happy with that kind of technologies. The bearing from the Lotus Elise S3 (purchased at eliseparts in UK) can be used to have the right signal required by the ABS. Good news, approved by Bosch Germany. I purchased the ABS at racedatasystems in UK. Delivery expected soon, in will be one of the first M5 sold.

- Rear axle: Not fully happy with the insane shaft kit I purchased from them. The axles will be changed for custom made shaft and using OEM Lotus and OEM Honda parts on other end. Good stuff. Axles coming within 2 weeks.

- The Hoosier R7 245-40-17 are large, the rear tire are touching the rear fender as well as the frame. ****! I don’t like the idea, but I decided to enlarge the car. I decided to go with the Hethelsport flare kit. I am waiting for delivery in December. The rear clam for BOE should be my first choice, but the money reason, I just decided to go with flare kit. At the same time, I will switch the wheel for 17x8 teams dynamics. Spacer will be added with a pilot extension on bearing hub.

- The shifter kit from Innovative was not perfect at all at the beginning, and the shifter ratio as modified was good. But the rotation over a oilite bushing is giving loose play. Since it is easy to make, I just decided to make the lever running on ball bearing. Easy to make with a lathe.

- The car was modified long time ago with a twin brake calliper at rear, and using the original one for the handbrake. I decided to switch to MC4 Wilwood for the rear handbrake calliper, weight saving, look better and better to adjust. Will be installed soon. All parts done to fit.

- The alternator fitment was too tight with the frame. I decided to install the alternator at his original position. Job done, not as the picture shown here. But still to do, find a place to install the coolant expansion tank. Tight fit... don't know yet the solution.

I will post progress with pictures and more details.

 

[elise/europa]

TB driven by cam, design concept

 

[zakria]

Wow, it is amazing information, with this kinda of power , have you done some drag race ?


If you don't mind, how much does it cost all this?

 

[elise/europa]

Wow, it is amazing information, with this kinda of power , have you done some drag race ?


If you don't mind, how much does it cost all this?

No I did not try the car on drag, but it is probably quite fast, between 11 and 11.5. Faster on straight line upto 230 km/h than a Viper Extreme, and by far faster than a Porsche GT3 RS 2017 stock.

Question of cost for the engine itself... to have that power, it is not very expensive, I know a guy who did the same power level with a stock engine boosted with a supercharge (turbo type). In my case, my plan was to obtain a reliable engine for high speed track, which is tought for the engine and tranny. My engine is probably built more for 600 hp than 450, drag strip wise. The transmission starts to have trouble after 350 hp. Because of all that, the engine was built and the transmission also. That said, by doing all my-self, without compromise, it is around 25K US. It was for me a funny enginnering project, not rational at all! The result is really crazy, power, torque, and starting like a OEM car. The lag is minimal since the Turbo is quite small and the plumbing reduced to his minimun. Plus, and this is one reason to have built this set-up with a Turbo, the car is meeting sound level on restricted noise level track. It is a lot of money, but the Lotus is so cool to drive on racing track.

 

[275 Turbo]

Love it! what an awesome car

 

[elise/europa]

Power curve and shift point with rought estimation of air friction

For reliability, the rev limiter is set at 8600, but it is clear on the shift sheet that the shifting point should be higher, with probably a rev limiter set at 9000-9200 where the torque is reduced and meet the torque on the upper gear. But it is not a race car, and reliability is a priortity.

 

[Ob917]

Insane love this stuff!

 

[Blerv]

Awesome build, thanks for sharing . Some people love to hate on the K20 but it?s just a brilliant starting place to build from.

 

[Roundabout]

I know what you mean by non-linear throttle response on turbo cars. In my Subaru, I have to back off the throttle as torque output from the turbo increases rapidly while the turbo spools in order to get a more linear feel for the passengers. The task of designing the cam for your cabled TB reminds me a little of shaping the needle on a SU carburetor to adjust the fuel mixture. Are you using math to do this? Have you plotted the VE of the engine?

Good luck. Very interesting project.

 

[elise/europa]

Are you using math to do this? I did it just by taking measurement on active solidworks sketch and playing with measurement until I found something cool. It is based on feeling. Too much mind usage to deal with the gas pedal at the track, I need to reduce it. After a discussion with a guy who did car prep in Australia where the race regulation ask for drive by cable TB on turbo car, I think I am on the good way. The linkage is adjustable also by playing with the starting angle on the primary cam.

Have you plotted the VE of the engine? No

 

[elise/europa]

Rear oarking brake Wilwood MC4 installed, with new wheel bearing (sensor for the ABS Bosch M5 coming) with extended (3/4 extension) pilot for the enlarged rear. Picture with 2x 3/8 shim custom made water jet cutted.

Pretty cool hand brake caliper. And the support to fit it is quite simple, laser cut 1/4 Alu plate.

The wheel are from the Lotus Elise S3. One stress removed, they fit outside and inside for the axle. Good!

 

[elise/europa]

Here the TB prototype cam driven. The TB spring is softer than the one shipped by S90racing. The spring is from the Honda original TB, the soft. This spring is not required, but I am affraid if the link fails to not have something to close the TB. The Spring used on the cam is heavier with medium pre-load. The result will be a softer pedal, and higher load to close the TB completly. For a propotype homemade, it is not too bad, but as good looking than production parts.

The bracket on the TB is weird. The original pulley is too big for the Lotus cable travel. Last year I just putted a smaller cam welded to the bolt on the original pulley. Now, and since it was altready on steel, I cutted a pulley, and welded a small piece. A little bit crappy, but if I am not fully happy with the cam drive system, I will be able to reuse the small modified pulley on the TB.

 

[Ob917]

Very interesting, keep it coming please!

 

[Spirit_R]

Love it! Must be insane to drive! Would love to see videos of it on the track when you have it finished

 

[elise/europa]

For those having the innovative shifter kit installed on the transmission, the shifter ball travel is just amazing. When I installed the kit last year, I did many trials to obtain what I think is a good shifter stroke. You will find on the picture the ratio used. In fact, at the beginning, I just switched the arm top to bottom, and modified one side. Since the actual design was quite loose with the use of a plain bearing, I redid the arm by using ball bearing.

It is possible to modify the side play, by bending the transmission shifter arm and grinding the shifter lock.

 

[cyow5]

Maybe I missed it, but I don't see how the cam will help with the turbo's feel. This could help if there wasn't any turbo lag, but the time delay with turbos is where you get that rough driveability. Production cars fix it by using the electronic throttle coupled with boost control. For instance, the GM LNF will go WOT quickly then use boost control, timing, etc to achieve the desired torque. Heck, with my wife's car, I can actually rev the engine a little by hitting the gas even when the throttle is disconnected, haha. Effectively, they program in a sort of cam, but you'd need a way to automatically pull the throttle back as boost comes on if you want a linear response at mid-level inputs.

 

[elise/europa]

Maybe I missed it, but I don't see how the cam will help with the turbo's feel. This could help if there wasn't any turbo lag, but the time delay with turbos is where you get that rough driveability. Production cars fix it by using the electronic throttle coupled with boost control. For instance, the GM LNF will go WOT quickly then use boost control, timing, etc to achieve the desired torque. Heck, with my wife's car, I can actually rev the engine a little by hitting the gas even when the throttle is disconnected, haha. Effectively, they program in a sort of cam, but you'd need a way to automatically pull the throttle back as boost comes on if you want a linear response at mid-level inputs.

Good point. You are totally right, and the mechanical cam can't be as cool as electronic TB able to pull back. I am not able to compensate for the turbo lag, which is quite minimal on my car set-up since thje turbo is quite small, and the aftercooler is very small also.

Forget the turbo lag for the discussion. When the potentiel boost is arrived, the power delivery is not proportional at all with the TB opening. A 25% TB opening can deliver maybe 50% of power. This is the goal of the cam to improve that. On NA engine, many time we are able to see excentric cam to open the TB. Why? Because the power is not proportional at all with the opening. By putting a excentric cam, they are improving that relation. This is what I am trying to do. Turbo is worst than NA for the proportional effect of the TB opening. Plus, the cable stroke on the Lotus is very short, and the cable is short either on the TB side. The cam as I designed will help to improve the relation. I don't think I will meet the target, but if my gas pedal at 25% should be able to deliver 25% of the available power, it should be a big improvement on curve.

For the lag itself, turbo is turbo, not as good as NA or supercharged engine. Unfortunely, I did the set-up with a TB driven by cable (for many reason). Anyway, with a TB drive by wire, I don't know if Hondata have the capability to pull back the TB. I drive a Focus RS as an everyday car, honestly, it is like driving a NA car, close too. Plus, it is powerfull for sure, but not that powerfull...

 

[cyow5]

Forget the turbo lag for the discussion. When the potentiel boost is arrived, the power delivery is not proportional at all with the TB opening. .

Fair enough, that's just the nature of a butterfly valve so that's definitely still valid. Heck, I've seen several instances where the max throttle opening was kept proprietary by a team just because peak power was at some opening less than 100%. That was RPM-dependent, too, but you'd have to get really tricky with the linkage to implement that without ETC.

 

[elise/europa]

Here the picture how I have modified the shifter linkage last year to reduce the side play. I cutted the linkage on the transmission, welded it back as low as possible, and little grinding on the locking device casing.

 

[elise/europa]

Coolant expansion tank with his new position with the new setup for the alternator. Crippy! I also changed the insulation around the headers.