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proracer

Racing 4 Cylinder Horsepower and Torque

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I am looking for information on the horse power and torque rating for the 4 cylinder car. Does any one actually have a dyno sheet they can share with me? I am more interested in the 4 Cylinder turbo information. I have figures that are all over the board. What is the highest reliable horsepower and torque output? What is the best 0-60 times? How about the best 1/4 mile time? How about the best gear ratio? Thanks.....Jim B)

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Jim - I can't give any expert advice on this, but Lottie's SE engine was rebuilt to a higher spec by her interim owner, who took lots of advice from Garry Kemp and others here. He reckons she's now running 370-390bhp at the crank with a S300 turbo and 1.25bar boost, and she certainly FEELS like she has an extra 100bhp since I first owned her.

She's SO quick now that I'm very cautious with full throttle - it just seems like a lot more energy available to break things...so I have no intention of dynoing her to prove or disprove his claims. Garry had an uprated engine for sale on LEW if you want to check the list of mods, and people like he and Dermot might be good people to PM for advice.


Proud recipient of the LEF 'Car of the Month Award' February 2008

"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: "Wow, what a ride!!"

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Thanks for the quick reply. The S300 turbo...What size is it? Has it been modified? Boost pressure? The engine in the photo I put in my post has 440 HP. Can this be a reliable figure?....Jim

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The SCCA World Challenge X180-R's often changed spec, what they could get away with in the race.

They didn't always use the normal turbos...

Find Brian Skeoch on here, he can put you in contact with the people who own the cars. He also has scans of the old race reports.

Not sure about the cars that raced in Europe.


Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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You need to speak to Garry Kemp, I'd cite him as a worldwide authority on what you can do with an Esprit engine.

His username on here is lotusmotors

Here's some info on an Esprit 4-pot in his Talbot Sunbeam!

The main challenge with this engine was keeping the head gasket in place; over about 380 hp they get a bit marginal. From the outset the plan was to at least double that figure. The liners were substituted for dutile iron; the head is dowelled to the block and head studs were custom items from the USA. The head gasket was replaced with an annealed copper gasket and a stainless steel wire ring is inserted into the top of the liner. The top deck of the block is machined and the liners are fully supported around the edge with a deck closing plate.

While the tuning is quite extensive it is fairly standard stuff; bigger valves, gas flowing, bigger chargecooler, bigger throttle bodies, twin injectors per cylinder and a BIG turbo. The core components though are stock Lotus: Bearings, block, head, even the SE / S4 pistons are standard.

The original turbo (a T5) was replaced with a larger turbonetics unit that is, as you might guess, as responsive as a supertanker. At launch the engine gets a 250hp hit of nitrous to wake up the turbo; which as I said earlier gives 3.8 bar of boost when up to speed. The car has been known to hit 60 in just over 1 second and go on to 170 in about 8.2 seconds. I can't say for sure; but I imagine it is probably the fastest Talbot Sunbeam in the world... :-)


88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

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True story. I cam currently campaigning to have him made a deity. :P


88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

For forum issues, please contact the Moderators. I will aim to respond to emails/PM's Mon-Fri 9-6 GMT. 

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I'm sure the 910 can make all kinds of power...

I know of a 93 SE here in the states that has 10 fuel injectors, a custom stainless exhaust, custom valves, crank, fuel computer, and everything else you can think of that was making over 600hp, was claimed up to ~920hp, and detuned for reliability.

But that wasn't the OP's question.

The race Esprit's would have had to follow rules for their series. That would have limited most of the crazy things they might have done for HP.


Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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The S300 racers were working between 390 and 425bhp (depending on race or qualifying).

Thats 24 hrs racing, but keep in mind that is for a race car.


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You can build a nice motor for road application to about 400 hp with a good torque curve. This will be is well very mannered, no lag or flat spots should have good reliability if used sensibly. If you are interested it is all described at www.lotusesprit.org. I have dyno figures but I don't advertise them.

Once you go over that figure you are into a whole new and much more expensive league.

Dermot

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I think the big factor here is whether you want outright power or driveability, and whether it's for road or track use. The old adage is that a race car should fall apart at the chequered flag, or you made it too heavy!

I love the extra oomph in Lottie, but I'm careful with it...PO had fitted a custom-made copper gasket to cope with the extra stresses, but it didn't last very long, and Garry kindly offered some advice for the recent rebuild (standard S4 OE Goetze jobbie). Only problem was the HD studs are bigger than the holes in the gasket...so I had to buy two as my mechanic ripped the first one!

I think if you're prepared to rebuild regularly, you can extract masses of power (mainly by turning up the boost and fuelling) but I don't want mine to need anything major doing for another 50k miles ideally. If I won the lottery I'd buy a bunker and pay Garry, Dermot, BigSi and Troy to keep Lottie and her sisters pristine and mechanically perfect - cost no issue. But until then, I'll just have to be a bit light on my (right) foot!


Proud recipient of the LEF 'Car of the Month Award' February 2008

"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: "Wow, what a ride!!"

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If you can recall, Lotus raced the Esprit in the SCCA and IMSA series. The cars were almost bullet proof. I am sure that problems did crop up but each was solved. The rules only allowed the cars to balance the engines. To keep the series competitive weight limits were adjusted. Later on better brakes and eventually bigger tires were allowed. Lotus did well in the beginning. Actually, to well. Restrictions, such as smaller turbos and added weight hurt the cars. I think overall, the Esprit faired well against the Corvette and the Porsche 911. Don't forget money speaks volumes. The more a manufacturer can spend on the car, the better chance they have of winning.......Jim

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I have an SCCA head on my car as bought from Garry kemp, also have DTA S60 pro ECU with wideband, 650cc injectors and a T35 hybrid turbo but no figs as yet need better HT leads and want a bigger charge cooler before I try for any real figs. Cooling is a big issue on a mid engined turbo car, a tubular manifold with external wastegate would be ideal along with better charge cooling, heat sheilding and better ducting to get rid of heat from the engine bay... cooling is king!!

To be honest I'd be happy with 380bhp from my spec...

Mark


Mark MacKenzie  Elise S2 135 Sport 

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