RBS_97Z28

iTrader: (2)

I had to put a Cat on my exhaust yesterday so the it would pass inspection here in Missouri. It's a 3" universal hi flo and I was wondering how much HP am I losing?

Thanks

taintedmeat

iTrader: (1)

3 hp?

Probably not a whole hell of a lot. Cats aren't the huge detriment to power a lot of people make them out to be, and after-market cats are even less of a restriction.

RBS_97Z28

iTrader: (2)

That's what I was hoping to hear. It muffled the sound a little, but not too much. I put it about 16" behind the ORY. I was thinking of taking it back off and clamping a 3" straight pipe, but not sure if it's worth the hassle now.

taintedmeat

iTrader: (1)

You probably don't notice much of a performance difference do you? The ideal situation would be to have a separate cat for each cylinder bank, but a high flow cat at the end of a y on a mostly stock motor shouldn't be much of a restriction.

RBS_97Z28

iTrader: (2)

No, I really don't feel any loss at all, just a slight sound reduction.

Question, why would 2 Cats per each bank be better than 1? That's something I've been trying to figure out since the '96 Z28's came with 2 and claimed more HP.

taintedmeat

iTrader: (1)

If you have one behind each cylinder bank on a dual or ypipe setup then each cat only has to deal with half as much exhaust gas passing through it, so even less chance of a flow restriction. Would also most likely prolong it's life a bit since 2 wouldn't have to work as hard as one to produce the same result.

SmokeySS

iTrader: (7)

That's an interesting place to put 1. They're meant to be up forward so they can pick up and retain heat to burn off any dumped fuel.

taintedmeat

iTrader: (1)

They'll work back that far though. On my 96 Dodge it had two cats right in front of the muffler, which was up under the bed. Never had any emissions issues with it.

RedWS6 00

For an inspection check dont the cats have to be in the stock position? or is this just particular counties?

RBS_97Z28

iTrader: (2)

The inspector told me as long as it's in front of the Muffler it's okay.