I don't want to belabor the topic, but in dealing with the catalytic converter failure I mentioned in an earlier thread, I just read that using gas with too high an octane rating can also burn a converter out.
Since I've been using premium (93) in my 380sl, whereas I think MB recommends regular (89) for it, I'm wondering whether this also contributed to my converter problem. OTOH, when I used regular, I got a significant amount of pinging, which went away when I used premium. So I switched to premium some time ago.
As I'm getting ready to replace one or both of the converters on my car, I was hoping someone could tell me whether I should continue using premium, go back to regular, or switch to a mid-grade (91 octane).
I was also wondering whether I should replace the cat on the driver's side with a true cat, a pre-cat, or simply a pipe, considering Tiger's statement that pre-cats aren't needed anymore (other than on the 3-way systems Karl mentioned).
In fact, while researching exhaust systems for the 380sl, I noticed that some have driver's side cat's, some have pre-cats, others seem to have just pipes, and prices differed significantly. For instance, catalyticconverterwarehouse.com has a driver's side cat made by Quali-cat for $67.61 delivered; convertergeek.com has a DEC that seems to have a pre-cat for $93.06; and a whole system for $311. made by Eastern (40061) only has pipes on the driver's side.
I've decided to go with a Magnaflow universal on the passenger's side, and I'd prefer to go with the Quali-cat for 67.61 on the driver's side. But I never heard of Quali-cat, and google didn't turn up anything on the company.
So any advice on the best way to go here would also be greatly appreciated.
Larry
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