you'll probably have 2.5" on an SSEi... no bonnevilles came stock with anything over 2.5"

EDIT: except maybe the GXP

When doing this hi-flow conversion, I want to just weld in a new flange in the front. Does anyone know where to locate a flange such as the one on the car, 4 bolt square? They don't show anything at the parts stores, nor do they show a square gasket for that flange, unless it is recessed for those little round gaskets just around the pipe.

I don't know if it'* because of the rest of my mods or not, but I simply don't get cackle on downshifts or when I jump off the throttle.
SLP headers, SLP high-flow, resonator delete, Hooker Header Aerochamber mufflers, 2.5" center/center.
The idle note is stunning, so is the cruising and normal acceleration, but, of course, when you go to WOT, it does sound a bit like a chainsaw.
Frankly, rrounds is the only Series 2 I've ever heard that sounded really good at WOT, but he has a full 3" exhaust, Aerochambers, and some black magic going on underneath to manage that sound...

I bought a Magnaflow 94006 on Ebay. $60 was the best deal I could get. That'* with free shipping, so that'* not bad at all. I will leave my resonator on the car. In doing research in other threads, I saw that it is best to keep the convertor as close as possible to the rear oxygen sensor to prevent insufficient codes?

I just ordered a complete exhaust for the 97 SSEi. It comes with a direct fit magnaflow high flow cat which is bolt on with the O2 sensor bung built in at the rear of the cat. The resonator is included in the intermediate pipe as well as a Walker or Maremount muffler, the choice is mine and the rear tail pipes have provisions for the tips. I will be picking it up tomorrow and should have in installed this weekend. I'll let you know that results since I'm told it'* a direct fit, no rework, modifications needed.

Well I installed the Magnaflow 94006 converter last night. As far as sound, I was not impressed because it sounds almost identical to before. I haven't driven more than 10 miles, so I'm not sure about any mileage increase yet. And as far as performance, I'm not sure because at 3.58/gal for gas, I'm not to interested in any WOT runs.

I am now considering the resonator delete now. Some have said I'll get crappy results, but I don't believe so. I removed the resonator on my old 99' grand am gt 3.4, and you couldn't tell any difference, so maybe that is what will occur with this as well. I do have some dual outlet SLP tips that I intend to install eventually.

Aren't you running premium?
Or is that your price for premium?

nope, just running regular!!! some may throw a fit about that. I'm not gonna be shelling about almost 3.80 a gallon for premium. I have been told by GM techs that regular will be just fine unless it starts to ping

I can tell you as a proud member of the popped piston club, you're damaging your motor. I suggest you quit trying to get power out of it. For timing to retard, the car must ALREADY have knocked for the sensors to hear it and try to protect the motor. Premium fuel is required in your car. It'* only $3 more to use premium per tank, and you'll even get better fuel mileage out of the deal, making the 'margin' much smaller.

All L67'* REQUIRE premium fuel. And we don't put alot of stock in advice from GM techs in most cases.

I could run some 110 octane if that would suit one'* needs. I know where I can get it for a fraction of premium pump gas. But I'm not gonna do that. I'm almost cheaper to drive my 14 mpg truck instead