98 4mula

iTrader: (7)

I won't be going the header route beacuse of smog. I have a 98, i was thinking of mids with the offroad y and have high flowing cats welded to them or just manifolds and high flowing catted Y.

What year had the best flowing exh. manifold? Also don't bother posting get LT's.

Thanks

SOMbitch

iTrader: (8)

01-02 had the best. They look like shortys.

98 4mula

iTrader: (7)

Thanks... Also looking for the highest flowing cat if anybody knows.

greatskiiiier

iTrader: (10)

middies with a catted y, but see if you can find a shop thatll pass you with LTs first, cant hurt to ask a couple of shops- go to a shady shop that looks like it should be shut down

therealcreeper

iTrader: (37)

just out of curiosity why would you go mid lengths and catted y and not longtubes and catted y?

i don't see how it's any less legal...

Blackhawk777

If he's in cali, you can't move the stock location of the cats. It's a HUUUUUGE no no. I know in nebraska, they don't give a sh*t as long as there are cats there.... hell I don't even think they test.

1'low92

iTrader: (5)

I got the magnaflow metallic spun cats and the are not that big and flow really well....

Blackhawk777

I've heard of those cats. How easy do they go into an aftermarket Y pipe? I'd like to keep my emission stuff when it's header time for me.

98 4mula

iTrader: (7)

If you get pulled over and the officer looks under your car for cats and sees nothing you get to go talk to the smog ref and you have to put your exhaust back to stock then pay a fine. If they see cats they won't fine you and you can be on your way. Cops know what LT's look like. Thats why i'm thinking of even getting exhaust manifolds and some high flow cats. I'm also curious to see if it makes a diff on the dyno.

98 4mula

iTrader: (7)

Anybody use random technologies cats? They supposedly flow very well.

Found this article that seems interesting http://www.installuniversity.com/ins...n11.122001.htm

Blackhawk777

Your car is a 98? You should make probably 5-10 more hp on the dyno with a shorty style and catted Y. It's not much more than stock. 01-02 cars, don't mess with it, their stockers flow just as good as shorties.

1'low92

iTrader: (5)

I had mufflex do my y pipe because I took the hooker ory and put in two cutouts and the cats but I don't think itd be that hard

therealcreeper

iTrader: (37)

well he was considering mids which would require him to move the cats anyway. i figured if he's okay with moving em then why not longtubes. but now he explained that so i have my answer haha.

i looked at some manifolds off of a "2000" ls1 engine that had been swapped into a v6 car (had a 98/99 throttle body though so i'm not sure) and i couldn't believe how terrible they looked inside. the 2 sets of "primaries" on each side of the manifold merge into a hole maybe a little bigger than a quarter. if you can i'd try to find a set of shorty's cheap. if the 98's and 99's are worse than the ones i looked at i'd be shocked that it can breathe at all.

or you could find some stock manifolds, maybe see if you can grind some of it out somehow, and run some cat delete pipes for stock manifolds with high flows welded in.

either way you're not going to gain a ton of power though

98 4mula

iTrader: (7)

I can get some 02 mani's fairly cheap or free then i'll go at it with them and try to smooth em out and open them up as well depending on how much material is there. Throw on a catted y and call it a day

RevGTO

iTrader: (12)

If you're going to have to pass smog, you'll need the 2000 only manifolds. They are formed like the 01-02, but they have provision for mounting your EGR. No EGR on 01-02, and you'll fail visual for that, no matter how nicely placed your cats are.

therealcreeper

iTrader: (37)

good point. didn't think of that. maybe shorties would be easier in the long run. they seem awfully expensive though for what they are.

by me i have no visual check and i don't think they do the sniffer unless you have a cel. we'll see how i do with my longtubes/ory next time hahah

greatskiiiier

iTrader: (10)

i still vote to find a shady shop, or maybe one a friend owns... if your slippin em an extra $20 they'll help you out... high flow cats and 02 sims wil fool the sniffer

therealcreeper

iTrader: (37)

that'd be the way to go but those shops are gettin harder and harder to find