I agree with this 100%.....however,1999Porsche911 cats are 11 years old...lucky?.....probably not...just well built...Porsche style!
I think Jareds problem which JELLIS enlightened us with,is that he was using a prototype cat that had issues.
I am sure that the stock cats are fine BUT the high flows are better!
I sure noticed the difference in how fast the RPM's went by from 4500 rpm and up after my AWE high flow cat install!


Stacy

 

Well, I already have all that done, only thing left is to find SC kit somewhere for reasonable price as I do not really want to buy it new. Will see...

 

Hey guys. I just got an email telling me about this thread.

Jason is 100% correct. Proto cats broke loose. The titanium catalyst was shooting out the tail pipe.

Here's the thing though. Just because one person has had an impeccable record with the SC doesn't put him in a position to just say "since it didn't happen with mine, it won't happen with someone else" (with a totally different car, even). The OP asked for scientific posts, essentially. Since something didn't happen with one person doesn't mean it won't with another.

Here's the facts:
The more power you put through an engine, the more chance for something to break. The more you push a car on a track, the more chance for something to break. The more work you do on your suspension, the more chance for something to snap loose unless you pay attention to it. It's just a given with these things. I believe that my situation was an extreme one. In 18 months, I was at the track A LOT... sometimes every weekend in a month. Read the first two sentences of the Excellence article on my car. I push it. I drive it hard. So, I've got ALL THESE MODS, including these proto cats. I've got all this heat going through there, all within 2k rpm of redline for 30 minutes a time, four times a day, 8-12 days a month, for 13 of 18 months. Extreme conditions, indeed. However, if the car did not have a supercharger on it in these conditions, I CAN'T SAY THAT IT WOULD OR WOULD NOT HAVE HAPPENED, and nor can anyone else. I DID know that I was selling Stacy a solid part that would serve him well. I honestly think that the cats should be able to handle this kind of abuse. I also honestly don't think that there are too many people on here that would put one of these through the paces like I do, andmost likely not someone with a cabriolet rolling on 20s. I got many professional opinions on the situation before selling it to Stacy. All fingers pointed at the cats, as they should have been able to handle it. But I wasn't going to pay to take apart that engine so we'd all know for sure. But in the end, that's as good of a guess as we can be.

I hope this helps with your buying decision. If you don't plan to drive the car like I just described, you'll love the SC. Otherwise, get a GT3 or sink a stupid, STUPID amount of money into your 911S and don't throw a SC on it. Heck, buy mine and enjoy the new engine (approx 410-415hp) on a VERY expensive suspension package. (I figured I could make a shameless plug after all this typing!) The link's in the sig. I'll just about put it up against anything as it is.

 

So, you bought **** cats and that was the problem. Running a properly installed VF SC at 5,500 rpm for hours at a time puts minimal extra stress on your engine. That is a scientific fact. Definately nothing that will destroy a quality cat. The TT exhaust is considerably hotter than a 996 running less than 4 lbs of boost as you described you do for hours on end.

 

That's not a scientific fact. What a silly thing to say. Who paid for this scientific research? Not Porsche. You? I am quite sure that the VF boys didn't. You do understand that the 3.8L S engine and it's lower and lesser ancestors have intermediate shaft problems which are magnified under stress, right? You also know that they have an issue with oiling sometimes, as they aren't dry sumped. Since the SC takes oil, who am I to say that this had nothing to do with it? I don't think it did, but it might have. These are not the same blocks that the GT and Turbo cars get. I know you didn't say anything to the contrary here, but I'm just trying to figure out where this science is all happening.

Yes, it was the cats. I would bet that there's a 90% chance that you are right, and that's what I've said all along. But there's a guy here asking for info and you have none to give, other than saying that you have had a terrific experience. That's a good place to be, so why are you in this? Why try to take a "100% sure" stance on this? I don't get it.

My point was that I have no idea if the engine were weakened previously. I don't want to just say, "It definitely wasn't the SC at all." To do so would... well... be unscientific.

 

If you had exhaust temperatures hot enough to melt any cats other than ones made with cheap alloys, you would also do damage to other parts of your engine, inlcuding valves. So, I would chock it up to just crappy cats, but there is no conveivable way that < 4 pounds of boost continuously would raise temperatures high enough to do any damage to quality parts. IF heat was the cause of the damage, it was most likely unburnt fuel getting into the cats.

My point is, just because you are unsure what the cause was, no one should assume that the SC had anything to do with your problem.

 

Scientific or not I find the idea of sucking in heavy cats fragments all the way up through the pipes and headers into engine while it was going on full throttle - well, quite improbable. There is no that much suction in the exhaust imho to be able to do such a stunt. But still something destroyed your engine. So I am curious.

 

Right. I couldn't agree more. I'm saying that no one should assume that the SC was 100% innocent, given the extreme situation.

 

FWIW, I talked to two unrelated mechanics who confirm that they have seen it happen before.

 

Having a VF SC on my 997.1 C2S I'm reviving this thread in hopes that VF-Engineering will chime in. My car will see 10-12 track days a year during the summer months in 100+ degree heat and seeing this thread has made me think twice about keeping the SC on, especially because it voids my extended warranty.

For the last 2 weeks I've been trying to get a hold of the guys at VF-Engineering to discuss small problems I'm having with the check engine light. Thus far, through PM's, emails and phone calls I havent been successful in receiving any decent help. Also why I'm considering removing the SC.

 

I am surprised to hear that the good folks at VF-E have been unresponsive, that is atypical. I will try to reach them for you this week.

I ran a modified SC for 1.5 yrs. Jared sold his to Stacy, then Stacy sold it to me. In that time, I loved it, but I did experience catastrophic engine failure one day at the track. Was an IMS failure. Could it have been elated to the extra power of the SC, maybe, who knows.

But I'll tell you this: I am considering doing the SC again, for VF-E really have a nice kit, and power is great. BUT, if I do go the SC route again, I will not take the car on the track with it. This is just a personal decision after having spent $17k on a new engine.
CATTMAN

 

From all the great things I heard about them I was very surprised too. The previous owner of my car had only great things to say about them and gave me Nik Saran and Jeff Moss's contact info. I emailed Nik, no response. I finally got a hold of Jeff on the phone and he told me to email him. I did and no response. So I called VF and described my problem over the phone and that was sent to the tech department with no response. I emailed the tech department myself and again, no response.

Reading about your IMS failure was another thing that got me worried about tracking with the SC.

 

Decided with the track usage my car will see I'm gonna take the SC off. With less than 5k easy miles on the SC, can anyone tell me what a good starting price might be? Thanks

 

Upgrade to a more powerful car from the factory (turbo) installing that junk is really stupid!! Your just making someone's mortgage payment.

 

I dont know about all that. They've sold a couple 997 hundred kits and only 2 cars, as far as I know, had problems. And in both cases fault couldnt be directly pinned to the SC (IMS and faulty cats).