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While researching the Garrett website I took a look at the four varieties of T25's that they offer. Are these newer versions of the ones on our Esprits, or is one of the four the one(s) we have? The first one has a horsepower rating far below the Esprit's 350#, but even the next three are suggested for applications "up to 330 HP". Since we have two, would our "limitation" only be 175HP (per side, so to speak), and that's how we "get away with it"? Just wondering.

John

P.S., they all seem to have "internal" wastegates (i.e., contained within the housing); is that the case with Esprits, and are they thus vented back to the exhaust or "to atmosphere" (normally a racing application only)?

Also, is the "water cooling" full time, or only for "heat soak" at shutdown?


Being second is to be the first of the ones who lose.

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While researching the Garrett website I took a look at the four varieties of T25's that they offer. Are these newer versions of the ones on our Esprits, or is one of the four the one(s) we have? The first one has a horsepower rating far below the Esprit's 350#, but even the next three are suggested for applications "up to 330 HP". Since we have two, would our "limitation" only be 175HP (per side, so to speak), and that's how we "get away with it"? Just wondering.

John

P.S., they all seem to have "internal" wastegates (i.e., contained within the housing); is that the case with Esprits, and are they thus vented back to the exhaust or "to atmosphere" (normally a racing application only)?

Also, is the "water cooling" full time, or only for "heat soak" at shutdown?

Garrett are pushing their Ball Bearing turbos (denoted by GT prefix) on the website and don

Edited by mike_sekinger

1996 Esprit V8, 1998 Esprit V8 GT, 1999 Esprit S350 #002 (Esprit GT1 replica project), 1996 Esprit V8 GT1 (chassis 114-001), 1992 Lotus Omega (927E), 1999 Esprit V8SE, 1999 Esprit S350 #032, 1995 Esprit S4s, 1999 Esprit V8 GT (ex-5th Gear project), 1999 Esprit V8SE ('02 rear)

1999 S350 #002 Esprit GT1 replica

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Very interesting indeed Mikle.

I am aware that turbos on our V8's, particularly I think the earlier 90's cars, sometimes didn't last long. Do you know why this was and is there something we should all be watching/maintaining to avoid this?

Thanks

Bob G

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Hi Bob,

I think that two of the biggest problem for our turbos are:

1. location

2. the wastegate capsules

The turbos are located in a highly exposed position and suffer, along with the oil/water feeds and returns, from horrendous corrosion. This corrosion is caused by a combination of heat and external factors (rain etc) and also affects the wastegate capsules (which are far from perfect in the first place). I honestly believe that in some cases, whole turbos have been replaced when the problems may not have been associated with the turbo, but with the wastegate and general exterior condition of the units.

For the corrosion, you could install some stainless feeds/returns, but these would have to be fabricated. There was a thread about this some time ago and I do not know if it resulted in a source.

You can also replace the standard wastegate capsules with some spanky stainless ones, which should assure their operation.

Beyond that, it is always good practice to allow the engine some cool-down time before switching it off. This will allow the temperature of the central housing to be reduced. This in-turn reduces the chances of any coking of the oil on the bearings and turbine shaft. It is not always practical to just sit there for a few minutes, so you could use a


1996 Esprit V8, 1998 Esprit V8 GT, 1999 Esprit S350 #002 (Esprit GT1 replica project), 1996 Esprit V8 GT1 (chassis 114-001), 1992 Lotus Omega (927E), 1999 Esprit V8SE, 1999 Esprit S350 #032, 1995 Esprit S4s, 1999 Esprit V8 GT (ex-5th Gear project), 1999 Esprit V8SE ('02 rear)

1999 S350 #002 Esprit GT1 replica

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Thanks Mike, very interesting. I bought my car late last year- the number of adverts stating new turbos on cars that had done less than 30,000 milkes was significant. Mine has done 28,000 and although they look pretty rusty and manky generally, all is functioning as it should so far as I can tell.

Best of luck with your completion!

Bob G

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Thanks, Mike, for a very thorough explanation, the kind I most prefer, but seldom see---I'm just not a "sound byte" kind of guy. They say "a little learning is a dangerous thing", thus "a lot of learning" must be a safer bet.

Regards,

John


Being second is to be the first of the ones who lose.

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