OK Bryant, here is your own thread highlighting the entire build process of your Monster project. I am already behind because your engine is out of the car and completely disassembled. I will go into the performance aspects of the build after we highlight the process up until this point. We have some very interesting information to share about your engine when we took it apart and inspected it.

Since 2002, when we first began building these engines, we have always stressed the importance of strengthening the internals. There are many companies that are pushing these engines well beyond their limits without internals, however it has always been our stance that beyond about 700 HP, it is not a matter of "if" the engine will fail but when it will fail.

The GT1 engine case and bottom end components are very strong to a certain point. The weakest link in the bottom of these engines is the connecting rods. Many companies want to believe / want the enthusiast to believe that these rods are very strong and bulletproof. The facts are that this is the same connecting rod that was developed for the 993TT. This connecting rod is
installed in the 996TT, GT2, X50 as well as the 997TT engines. These rods were the weak link back in 1996 when we were pushing the envelope of that engine and they continue to be the weak link in 2009.

A fair amount of the engines that we disassemble prove this weakness. Some engines, like S-351's are the lucky ones where the rods bend. The next step is the cracked rods, like S-351's. The final destruction comes when the rod breaks and punches a hole in the side of the engine case which at that point completely destroys the bottom end of the engine. Much of the fatigue comes from high power and these rods cannot withstand sustained forces against them without bending. They can last for a while if the engine is pushed only for a few short acceleration runs here and there but will never last on a race track or at sustained high loads where consistent heat and pressure are maintained.

There are very few enthusiasts that want to spend $10K-$15K to build the bottom end of their engine for strength purposes. Additionally, this expense is harder to justify when the build only addresses the strengthening aspect of the engine and the performance gain from this procedure is minimal. However, as I mention above, it is not a matter of "if" but "when" the engine will fail and the damage caused by one of these failures is much more than the cost to prevent the failure from happening in the first place. These are not scare tactics, this is REALITY. Engine building is not a huge money maker as some may imply when you consider the actual hours for assembly, 10's of thousands of dollars invested into tools, assoiated liability and warranty we provide.

S-351 must be a lucky guy because we have never seen a rod cracked like this. All of the engines we have seen like this, the rods are either bent or broken. We have never removed a rod that was bent and cracked. It is a good thing that we didn’t dyno the car before we removed the engine. I am sure that a couple of pulls and the rod would have broken and caused some major damage.

Here are some pictures of the car, engine being disassembled and the connecting rods.

























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Todd, what kind of power was this car making? Guys on 6speed said 680whp, do you know how much torque?

 

I think somewhere around 650 TQ.

 

Bryant (S-351), just wanted to ask a few questions:
1. how many miles did you put on the car with the 700 kit?
2. how many miles did you put on the car with the EVOMS GT30 kit?
3. how much hp and torque did the 700 kit make?
4. how much hp and torque did the EVOMS GT30 kit make? is 680 hp and 650 tq on a dynojet correct?

 

So what year is this car and how many miles?
Looking forward to this build.

 

David,

You sure are curious about this. Why does this peak your interest?

 

Well it's silver, and it is going to be fast as all hell....

Project "SilverSMOKE" ?

 

I think those are valid questions. I totally agree with you on the when the rods will fail but it is important to know how long the engine lasted at high power levels.

Looking forward to seeing how this project will evolve!

 

Another EVOMS monster! This will be good.

 

The Switzer thread on here talking about 997tt engine with their amazing "forged rods" and "dry sumps" is a bit of a clue to a Porsche turbo newbie.

Porsche turbo engines have been like this since the late 70s and the limitations of the turbos was truly tested with the 993 GT2 racing of the mid 90's. around 800NM/600ftlbs is what bends the rods and the mid 600hp level will cause the fractures and or other case exiting events.

If Switzer had "been around" a while they would know about the history and how the race problems were solved by the Carrillo solution. Despite the Switzer thread talking about the robustness of the 997tt, as Todd points out,below the heads it is virtually identical to the 993tt so will succumb to the same forces.

The Switzer engined Porsche turbos doing the 60-130mph under 7s will break/bend the rods, it is just a matter of when.............