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Discussion Starter #1
My understanding is that the V-8 engine in the later Esprits was capable of a lot more HP but was detuned so as to not destroy the Renault gear box. Is this the case? Has anyone swapped out the gear box and upped the HP? What did you use and how much HP did you achieve?
 

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Existing gearbox can be upgraded with $4k in parts to handle more, but lots of other things have to be upgraded in that game...engine bits, half shafts, etc...


1998 Lotus Esprit V8
 

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There is an aftermarket box available. I think Quaife makes it. It's a dog box. Bring your BIG checkbook. "They say" it is kinda a biatch to drive on the street but should handle anything you can throw at it. Look into it if you got the gonads.

I also think there's a few out there with the Porsche G50 or whatever box. That one's said to be a rock crusher, but much more mods will have to be made, where as the Quaife box is supposed to just drop in.

The other thing to do is to beef up what you have. Much stronger main shafts are available so you can actually apply full power in 5th gear withougt grenading the gear box. They don't have a hold drilled through the shaft where the 5th gear mounts or something. There's some other mods too that a good Esprit centric shop can do to beef up the existing box. Hang out on the Yahoo TurboEsprit list and ask there if you're serious.
 

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It is true. The engine is "knee-capped" because of the weakest link... The gearbox. primarily 1st to 2nd and 2nd to 3rd ratio increments are a bit large, read wide ratio, which makes a stressful life for the synchros and 5th is a cobbled (extended shaft) gear that is somewhat fragile.

There are solutions, for $$$, like the gear set "drop in" from GTO (UK Quaife distributor) and Holloway in Mn. 1st gear is straight cut, rest are typical bevel.

HP/torque increase by the usual route:

Increase air flow by reducing restrictions via K&N filters, 200 or 100 or no cell cats and optionally lose the muffler and replace with straight pipes. If you lose your muffler you can ditch your spare tire under front bonnet and keep the weight balance pretty natural... If you drop the muffler and spare you might need to tweak your Bilstein/Eibachs; oh, you don't have those? See how this works?

Reduce intake temperature; via h2o injection or intercooling

Increase boost by increasing spring tension on the boost actuators; dangerous plan because it's not "seen" by ECU; fakes it out.

Up modding the ECU to allow more boost in 1st and 2nd gears (more aggressive mods will allow full boost, plus some, to all five gears)... Watch out for the weak gear set; doing the aggressive mod alone could be counter productive without cooling the intake temp... Oh, and adding more boost in 1st is mostly worthless, especially with stock gear set ... You'll burn your tires...

Optimally, do all of the above in the correct balance... Whatever that is... An expensive mobile lab experiment.

And ditch the Pontiac steering wheel; it reeks, at best
 

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Spree I spoke to Gonzalo about the kit for the tranny and he says it's holding up really well.
Pilot, That's good to know:clap: he's had it a few years and I *know* he's put it to the test, in a good way, so that speaks well for its extended life.

Mine's underneath my bed, no kidding. I've been wondering if I should be proactive and install it while the stock box is healthy or wait a while. Can't wait until a failure, if one ever happens, because it's not a 100% replacement; you have to have a few surviving pieces to complete it. I've also been hesitant because the dang car looks so clean underneath, narry a smudge or drip of oil from seals and did not want to disturb what's not leaking.

Thanks for checking.
 

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I guess the best thing to do would be to do it when it's time to change the clutch. The tranny's out anyway so you might as well do it then.
 

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It really doesn't have to be timed to be done with the clutch. Removing the transmission in an Esprit is one of the easier jobs, it comes right up and out of the back with very little else needing to be removed. With an engine lift, the right tools and some experience you can probably do it in 2-3 hours with an assistant. In any case when you do it figure on also doing the clutch. Budget another $2.5K just for that! While you have the box open figure on a set of syncros too. As you can tell this can be an expensive upgrade!
David Teitelbaum
 

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Discussion Starter #9
Wow, thanks guys. You have more than answered my question. I don't actually have an Esprit though. I was just asking out of curiosity. Late next year or early the next, I will be buying a Lotus and I am leaning toward an Elise but have been thinking a V-8 could potentially be more fun. I am just mining info.
 

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The transaxle is not as bad as most make it out to be. I have a good friend that has tracked his race prep Esprit V8 with 470 HP every weekend and he regulary shifts it between 5K and 7K RPM's. He has had no problems over the past three years of track only application. The main thing is watch speed shifting, first, and second gear.

My car produces 440 HP and has a Lotus red ECM/straight pipes and I have had no problems for the past four years. But, I watch my shifting and treat it with care.

Also, I have three extra stock UN-27 plus a lot spare transaxle parts. One of the UN -27 as a Quaife differential.

Cheers,
Alan
 

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The Quaife is great, I definitely recommend it.
It's expensive and not necessary for everyone, but I do like mine.
What is the thinking about limited slip use on the track? I'm not an expert on car dynamics but I enjoy a bit of track time and if I make a mistake and give too much gas at the apex of a turn I loose grip on the inner tire but the outer tire stays planted and I stay on course through the turn. If I were to give a little too much gas at the apex with limited slip wouldn't I pretty much be assured to have the rear come out and hit the wall?

I'm all for going faster and I have considered getting the Quaife. Does anyone have track experience with it on how it performs in practice to scoot me around the track quicker?

Knut
 

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I've driven my 89SE on track with and without the Quaife, with SE wheels and V8 wheels. And I have driven my 89SE (when it had the original open diff) and an X180-R (with a ZF clutch type LSD) back to back on the track.

With the open diff I we were always spinning the inside rear tire and all the weight and traction were only on the outside rear tire through almost every turn. But none of the power... So you end up coasting through the turns and then the spinning tire will jolt when it regains traction.

With the LSD, there is so much more traction through the turns because you are using both rear tires. You can tighten your line by adding a bit more power.

You can spin the esprit with either diff.... But yes, with an LSD both tires will tend to break free at the same time, and that can be especially true in the rain. You really have to re learn the car after adding the LSD.

The Quaife doesn't seem to add any understeer in my car like the ZF clutch type does in the X180-R, and that is probably because it acts like an open diff unless there is a difference in wheel speeds. Where the clutch types are locked until the difference in torque breaks them free.
 

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I think it will am sou quicker due to being able to give the car a lot more throttle before the tires slip. Correct.... Both rear tires would slipmvs just the inside but it's a lot harder to get both wheels to slip.

Unfortunantly my only experiencem is in a fwd car, I hated doing 1 wheel burnouts at 75 mph coming out of turns.... Much much quicker for me with a LSD, I would think the same would be true for your car.
 
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