Mike Sekinger's 1999 Sport 350

Mike Sekinger from Bristol, UK owned a 1999 Sport 350 in Silver, with a black/blue/carbon interior.

Model:	Sport 350
Year:	1999
Colour:	Silver
Interior:	black/blue/carbon
Driving Style:	Should be on the track
Miles per year:	2,000 - 4,000
Owned Since:	July 1999
Purchase from:	Dealer, Alan Kerr, Paington
Serviced at:	Various
Other Cars:	VW Caravelle - kiddy carrier
Why an Esprit:	Beautiful shape
Previous Lotus':	1997 V8 - Mustard Yellow & 1998 V8-GT - Titanium
Upgrades:	See Below
Problems:	Main radiator and exhaust replaced under warranty
Info:	All of my work has been done by Mike Haines Racing. He fabricated a custom exhaust (but retains the pattern in case anyone else wants one). I'm keeping the cat's for now, but will experiment when I get the car back. There is a 'race ECU' coming to me from the US, so i'll get someone to check the code and see if I can get rid of the cat's safely.

 

Project GT1 (based on V8 Sport350 donor vehicle)

This project was devised to creating a road going ‘replica’ of the mighty Lotus Type 114 race car (Esprit V8 GT1). Lotus prepared three cars and successfully ran two of them in the 1996 BPR Global Endurance series.

Following some digging around on the Web, I discovered that one of the original Lotus chassis (114-001) was being campaigned in GT2, by Mike Haines Racing ("MHR"). After several phone calls, I arranging to visit MHR and look over the racecar. After some lengthy discussions and upon finalised the initial scope, MHR agreed to take on the project. Not long after the start of the work, the project scope started to extend. This additional work saw the duration of the project grow from an expected 2 months, to almost 9 months.

The main reason for the additional work stemmed from a weight reduction programme to complement the overall image and expected power increase. The car’s weight has been reduced by just over 100Kg. This combined with a power increase to 450bhp give the car a new power to weight figure of 375bhp/tonne. To put this into context, the new Lamborghini Murcielago has a figure of 351 bhp/tonne. Should be fun!….

The following images take you through the project:

Initial thoughts

After looking at some images of the racer, I set about to ‘Imagineer’ the look of the project. This image is based on a shot taken by David Lord Photography, of testing at Rockingham.

 

Left: Imagineering Image
Right: initial project overview

The initial scope involved making the external look of the car as near as possible to that of the racecar. The first stage of the project was to ‘offer’ up some the race parts to see which of the existing panels could be used and which would require some customisation.

Bodywork

After deciding to replace the Rear Deck/Engine Cover with a carbon fibre alternative, it was necessary to design a tilting mechanism for the rear wing. This allowed for the necessary clearance for the rear deck to operate, given that the engine cover on the racer is physically removed to gain access. Due to the lightness of the engine cover only a single telescopic strut is required.

 

 

Left: Rear Wing endplates
Right: The LH wing NACA is used on the race car for additional transmission oil cooling. MHR has actually fitted a second duct on the RHS of his car for even more cooling. Mine is used to route cool air for the exhaust area.

 

 

Carbon doors and lightened/milled 'SIP' bar

Under the guise of extreme weight reduction, it was agreed that the doors would be replaced with carbon fibre versions. This would save a massive amount of weight and also further exaggerate the ‘race’ feel of the interior. The door armatures were machined out to reduce weight further and finally polycarbonate windows were designed.

 

Left: Carbon roof panel including NACA duct for transmission oil cooler
Right: Rear Deck/Engine Cover Carbon/honeycomb with oval vents

In order to utilise the front wheel arch, it was necessary to accept the use of the front splitter. It was agreed to create a version with a shortened floor, as the racecar has a full-length flat floor for creation of significant down force at higher speeds. The front splitter then in turn requires that the ride height be variable. Some adjustable platform shocks allow the car to be set-up for road or track use.

 

Left: Carbon front splitter with shortened front floor and 1/4 front bumper section
Right: View from below of the very large front Splitter

 

Right: Wheel arch extensions (with brake venting of rear of fronts)

When using the wheel arch extension, it became necessary to use a second lower sill extension. This was purely for aesthetic reasons.

 

Having gone for the front splitter, it made a lot of sense to go for the rear diffuser. This was also designed to create down force on the rear. Again, a shortened floor was employed. After looking at the diffuser, it was agreed that a customised exhaust set-up would be needed. This would replicate the racecar with two central exits above the diffuser. Coincidentally, the 2002 US spec Esprit has moved toward a central exit system like the Elise.

 

Exhaust & Rear Diffuser

Wheels and Brakes

Instead of trying to find a road wheel with the correct offset, it was decided to use the race wheels. This required the design of a custom Hub and Spindle Adaptor. This would allow the use of the magnesium alloy centre lock wheels and take account of the added track width to match the racecar. This also kicked-off the design of parts for the brakes. The brake system was to be given a very healthy upgrade to cope with the possibility of some serious Track Day thrashing. It was decided that the existing 4 pot front callipers would be moved to the rear, and the fronts replaced by 6 pot callipers. These would be mated with huge grooved discs. The existing rear calliper was used for the Handbrake.

 

Centre lock magnesium alloy wheels (18"x11" front - 18"x14" rear)
Pirelli P-Zero Rosso tyres (225x40ZR18 front - 335x35ZR18 rear)

 

Left: Front 6-pot AP Racing front calipers over 356mm grooved discs
Right: Rear 4-pot AP Racing rear calipers over 330mm grooved discs (plus hand-brake caliper)

As the project was always intended as a serious track day tool,
I managed to persuade MHR to part with a spare set of magnesium rims and slicks.
Both fronts and rears have almost exact rolling radius and are 250 and 315 wide respectively.

Engine Modifications

After some deliberation, it was agreed that the full charge cooler modification would liberate a significant power improvement. MHR then designed the installation and looked into areas of restriction within the existing set-up. A fabricated plenum was designed to allow for the charge to equalise more effectively. The charge coolers were to be installed in the rear boot area. Due to the anticipation of increased boost levels, a single Dump Valve was installed to vent unwanted pressure. MHR also fitted an additional throttle spring to ensure that the butterflies remained fully closed on lift off.

 

“Charge cooler installation” & “Second charge cooler installation” More Info

 

Engine Compartment Overview

The original intention was to have some switchable boost settings. Due to the restrictions of the Lotus ECU, this was not practical/possible. With the long-term plan of moving to a MoTec set-up, it was agreed to go for a single boost setting. On this basis I decide that I would employ a modified Lotus ECU that I obtained from the USA. These are the dyno plots from both the Sport350 and ‘Race’ ECU’s.

Transmission

The standard transmission has been retained for now. The transmission oil cooler was added to take use of the roof NACA. It was also seen as a useful modification to help the ailing transmission. There are further modification planned for the transmission, and those will also require an additional cooler. The pump is sensor controlled and fits directly to the transmission casing.

 

Transmission Oil Cooler

 

Left: Air flow for the Transmission Oil Cooler comes in from the roof panel
Right: Fabricated Plenum and cam covers.

Interior

I decided that I wished to replace the existing sports seats with a pair of carbon shelled race seats. This would also enable the use of full race harnesses. I eventually chose a pair of Corbeau seats. The passenger seat is a little wider than the driver seat to afford some additional comfort. Once the race seats were installed it became clear that a detachable steering wheel would be needs to allow sensible access. A suitable race wheel was chosen and horn buttons were added. A custom boost gauge and pod were also added. Finally, a discreet push button started was added and located within reach in the centre console.

 

Left: Pair carbon Corbeau race seats - both with Willans 6 point harnesses

 

Removeable 330mm Momo race wheel — Cockpit boost guageBodywork mods (all GT1/2 mouldings)

 

Upgrades

Twin charge-coolers with single twin pass radiator — Hybrid turbo (Larger housing and compressor wheel with 360 bearing) — ECU modifications with boost increased to max. 15psi — Carbon/metallic AP Racing paddle clutch — Alloy expansion tank/swirl pot for charge-cooler — Custom alloy plenum to balance charge and provide for dump valve (BOV) — Engine sensors (3 bar MAP and fast High IAT) — Alloy coolant expansion tank — Transmission oil cooler and temperature switched pump — Braided engine and transmission hoses — K&N performance Air Filters — Custom centre exit exhaust — 6-pot AP Racing front calipers over 356mm grooved discs — 4-pot AP Racing rear calipers over 330mm grooved discs (plus hand-brake caliper) — Custom bells and brackets — Aeroquip brake hoses front and rear — Two-way adjustable dampers with variable platforms - 1500lb springs all round — Custom hub spindle/adaptor for offset of centre lock wheels — Centre lock magnesium alloy wheels (18"x11" front - 18"x14" rear) — Pirelli P-Zero Rosso tyres (225x40ZR18 front - 335x35ZR18 rear) — Silicon coolant and boost hoses — Removeable 330mm Momo race wheel — Cockpit boost guageBodywork mods (all GT1/2 mouldings): — Carbon/honeycomb rear deck with oval vents — Carbon doors and lightened/milled 'SIP' bar — Carbon front splitter with shortened front floor and 1/4 front bumper section — Carbon rear diffuser with shortened rear floor — Carbon roof panel including NACA duct for transmission oil cooler — Carbon side sills and skirts — Wheel arch extensions (with brake venting of rear of fronts) — Carbon medium downforce rear wing with machined pillars - carbon end plates — Pair carbon Corbeau race seats - both with Willans 6 point harnesses — Racing door mirrors — Carbon NACA in rear LH wing for additional cooling — Additional venting in rear bumper.

The car is approx 2" lower and 6" wider and the GT panels look fantastic. The car has not been put on the scales or the dyno yet - but I'm hoping for at least 100Kg weight saving with about 450bhp.

 

MHR are currently making the necessary changes to install a MoTec system.
This will guarantee that th car is not ready until early January.

Dyno Info

Project GT1 has just been to the Dyno for setting up. There were lots of problems in managing to secure the car to the rollers. On the
initial calibration run the car was squirreling around all over the place, spinning and slipping etc. On this run due to the slipping it
only registered 261bhp at the wheels!

On the second run it registered 370bhp at the wheels, which gives a calculated flywheel figure of 405bhp. This is believed to be slightly
down on true bhp due to heat soak and charge cooler efficiency on the dyno. This power was achieved on 0.5bar boost, as the Lotus ECU starts to enrich (dump fuel) at exactly 0.62bar.

MHR are now planning to install the MoTec ECU in order to allow for complete configurability on the engine. All in all it was a good result, but highlights the fact that you can only do so much with the Lotus ECU.

 

First Drive Thoughts!

The car is very wide and sit extremely low - even for an Esprit. The suspension is a lot firmer than the Sport350 but not so much that it jars as you drive along. Don't get me wrong, you can feel every imperfection, but you don't get a hard jolt - there is some compliance. The acceleration is fantastic - the power is delivered smoothly (as you'd expect with the same boost as standard), but on uneven road the wheels spin in 2nd, 3rd and 4th.

It really needs good contact to get the power down smoothly. The extra power and torque are well complimented by the reduced mass. The steering is even more precise that I remember it, but I've lost a little of the steering lock which means you have to think a little more about tight manoeuvring. When travelling along the motorway, you tend to get bounced about a bit - it may be necessary to soften the setting slightly.

The brakes are absolutely brilliant - they feel incredibly strong and it appears that the ABS is definitely 'less eager' to interfere under hard braking. The seats and harnesses work really well - you are very secure and the driving position is excellent. The steering wheel distance is just right, although it is still a little difficult to see the instruments properly. It is very noisy - mainly due to the lack of soundproofing. At 130mhp you can't hear the horn!.....

I'm really happy with the result and I can't wait to get behind the wheel in a decent circuit.

mike_sekinger@hotmail.com