F40 LM Turbo Difference

fwiw, the LM Turbo and the "LM turbo" are not the same turbo. lol

iow, what was installed on the offical LM car is not the same as what ferrari sells for the regular street car. I don't think they are even made by the same company.

I have the replacement turbos on my car, puchased under the "LM turbo" ferrari part number. They do spin up faster because they use bearings instead of bushings. They also have a small lip on the edge of the impeller blades. There may be other things but those are the major differences that I read about. They are a bolt in replacement for the original turbos (same boost pressures, no change in wastegate or ECUs or intercoolers).

The Turbos on the official LM car are quite different, afaik.

 

From what I have read, 100% correct. The replacement "LM" turbochargers are not at all like the actual ones used on the official LM's. Pretty sure that is just a nickname they got like Daytona that really isn't the cars name.

 

Time to use the Garret Variable vein units. When it comes to turbo's make sure you have them rebuilt with in specs seen way to many times shops cut corners and just having a turbo fall apart is a disaster. Would be nice to see some side by side comparisons with the stock IHI units and the LM spec turbos.

 

Actually I have had a recent Turbo experience with my F-40 that I want to share. The right hand turbo (compressor side seal) went bad and the turbo was allowing oil into the the intake. I removed both turbos from the car and I found something different about the two turbos. The R/H side had a clamp holding the center cartridge to the turbine section and the L/H turbo has 4 bolts instead of the clamp. I did not understand the difference between the two turbo's but I assumed that at one time the car had a turbo replaced but I went ahead and sent them to a turbo overhaul shop. The shop then called me to inform me that one turbo could be overhauled and the other could not be overhauled due to parts availability. Without going into all of the boring details here is what I have discovered. The clamp type turbo is what is commonly referred to as the "LM" style turbo, and the bolt type turbo is the original design used on all F-40's from new. Here is the really interesting part. The clamp type was manufactured by IHI directly for Ferrari as the "upgrade" turbo. These newer type turbos have (as stated earlier in this thread) roller bearings and a different compressor wheel. The overall performance of the two turbos are nearly identical. However the newer "LM" replacement turbos CANNOT be overhauled because there are no parts available for these newer type turbos. The older type can be overhauled very easily as the seals and thrust bearings are very common. The cost to overhaul these is about $500 each and the price for a new pair is about $10K. The photos below show the differences in the two types of turbos and the part tag on the turbo.
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Good info - thanks!

 

+1 great info thanks

I replaced the 162/163s with the new LM turbos because I couldn't find rebuild cartridges. Any info where these can be obtained?

 

To clarify your question, you have the LM style turbos, correct? If this is the case, the center cartridge (which contains the bearings, thrust bearings and seals) cannot be overhauled because NO parts are available. IE IHI does not sell any parts for these turbos including the center cartridge. I am not sure this is a Ferrari related decision to make parts available or not. The turbo shops that I have talked with all say that the parts are all proprietary to Ferrari so one can only guess. The older style turbos with a journal bearings can be overhauled because all of the wear parts are the exact same as other very common turbo mfg parts. Are you currently experiencing a turbo issue?

 

512BLU, I have the newer LM turbos on the car now, but still have the originals. The right one is blown, so would love to rebuild them both and keep as spares.

 

I would call IHI directly or any IHI dealer and they can get them rebuilt.

 

One good reason to stick with them.

 

Sorry to interrupt guys....

But, could one of you please tell me what the IHI model / serial numbers are on any of these units? If not available, do you have performance specs for them?

The reason I'm curious is that I want to see how they compare with the turbo's on the V8 Lotus Esprit.

The basic formula for both F40 and Esprit is very similar ---

F40 ----- 3.0L V8, 2 turbos, flat crank, 478HP
Esprit --- 3.5L V8, 2 turbos, flat crank, 350HP (but 470HP with factory ECU upgrade)

The F40 also does run a bit more boost at nearly all map points, and the Esprit boost mapping is tuned to be a lesser-stressed engine. But, many in the Lotus world believe that engine is capable of quite a bit more output than the factory "allowed". Of course, the wimpy stock Renault gearbox can't handle it, anyway --- leave it to the British

 

IHI doesnt like to release specs on their turbos. One would need to pull the housings off and measure.

The Espirit turbos are wimpy T25's, they wont make more than 500hp combined.

 

When my turbo went out the rotor contacted the housing so not sure if it can be rebuilt. Still checking on that. Ppl with good/working turbos may want to rebuild them *before they go out...

 

Ahhhhh....But, that is why I asked ---- I have a "turbo upgrade" planned for my Esprit

Incidentally, I just noticed the pics posted by 512BLU show the info was looking for --- must have missed it at first pass.

 

Also, after reviewing the pics of the "standard" and "LM" configurations, there are (2) very distinct (and related) design changes there.

1) The material for the pressure chamber was changed from cast aluminum to cast iron
2) The interface went from bolted flange to clamped coupling

I have no doubt the reason for both these changes was for thermal performance criteria --- HUGE difference in the heat transfer characteristics of the materials and the joints.

The "LM" variant has the cast iron pressure chamber (earlier referred to as the 'center cartridge'), and the clamped joint ---- cast iron conducts far less heat than cast aluminum, and the clamped joint nearly "decouples" the 2 components thermally. The net effect is that heat from the "exhaust side" of the turbo is not transferred as easily to the "intake side" with the LM configuration.

Of course, it doesn't take a rocket scientist to figure out why that would be a better design for an F40 engine operating at "LM" specs and in race conditions.....

 

Good idea! If you are looking, there are certain warning signs: oil seepage, smoking etc.

 

Pressure chamber? You mean the 'turbine housing' right and if so it has always been cast iron. An aliminum turbine housing would melt.

Actually the reasoning for this method is more geared towards the ease of maintenance. I have owned turbo vehicles with both setup's and believe me the 'clamp' rules!!

 

The terminology I am using relates to "Turbine Engines" --- perhaps that's unclear when applied to a "Turbo Charger". The part of the turbo I am referring to is this (blue arrow).....contains the shaft and the bearings, connects the compressor housing to the turbine housing.
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That is the 'cartridge housing' and it is also cast iron.

 

From the photos, it looks to me like it is cast iron on the "LM" unit and cast aluminum on the "standard / original" unit --- can't always determine things just from pictures, though.

BLU --- Would you care to confirm what the materials actually are, since you have the parts in hand? --- a magnet would be the simplest, conclusive check. Thanks.

 

Hey guys. In the photo with the arrow, that is not aluminum it is bead blasted cast iron and I'll admit it looks like aluminum!! I promise you it is cast iron / steel. IE, there is no difference in the materials used on the two different turbos. I was told that the reason that the "LM" turbos have a clamp rather than a bolted flange is entirely due to the ability of reclocking the turbo to allow properly aligned installation more easily. After the turbo is bolted on the header flange and most of the other parts are installed on the turbo there is not much room to work around loosening and retighting 4 bolts!! I post a few other pic's of this later today.

Thanks.

 

Thanks for clearing that up --- makes sense

I'll still maintain that having the better thermal isolation from the clamped joint configuration is a nice "bonus" benefit --- even though it apparently was not the primary design goal.

 

These Are Real LM Turbos, compared to a stock turbo. The LM Turbos have a rectangular exhaust flange not a square one.
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