Header and Y-Pipe Question

[atclate]

So, I'm looking into upgrading my car.
I dug up this thread about "Dat's y-pipe"(http://www.solaraguy.org/viewtopic.php?t=28426) and found out that my car has the "pre-cat" on it >_<
[the picture of a solara with pre-cat is at page 18, and without a pre-cat is at page 14]

So, I missed out on the Dat's y-pipe group buy, the JP Performance group buy, and also another private JPP sale. That's all fine... I will figure out a way...

I guess I have a few questions...

1) Does those pre-cats kill my performance?
2) Is it illegal to install an aftermarket headers? ( I live in California )
3) Will the e-bay headers do me any good if I'm not planning on doing really great mods like supercharger? (at least not in the near future)

4) Is anyone selling their performance header??? ha ha ha just in case

[Mole]

it's not illegal, you just won't pass smog if you daily drive you car.

thats why it's fine to buy when products have a stamp "made for off-road use only."

[Astro]

You can pass smog as long as they don't get you on a visual. My last inspection I would've passed if I didn't have a bad (in my case gutted) cat. That was my only problem. Just got to a hole in the wall inspection station, I've got one here in North Hollywood, I'm sure you could find one.

[Eye8Pussies]

I won't comment on the other things you asked since I'm not fully familiar with Cali laws...

but it's a definitive YES that the pre-cats kill performance. especially IF you are boosted, since the gains/losses are then exponential

[atclate]

Do the visuals check for pre-cats too?
Or do you mean I will fail the smog only because of too much smog?

[Astro]

No, the pre-cats won't matter, it's the rear cat on the flex pipe. Some stations do visual checks, so if they see the headers they may fail you just because you have them. The place I went to didn't care and ran the test, which I would've passed if I didn't have a faulty catalytic converter.

[Dawgz]

I got OEM NON-cali spec headers, and the dat's ypipe.

and got a URD TYPE B o2 simulator so there is no check engine light with the absence of the pre-cats, since the cali spec ecu wants to read a tad bit diffrent value from the bank 1 sensor 2 (o2 sensor after the cat).

I have dyno results on here from before and after.....and the power increase is stupidly insane.

30whp diffrence peak, and at 6k rpms, the power went down to 140whp with the precats, with the new system it stayed at like 190ish?


Here, reffer to this thread....

http://www.solaraguy.org/viewtopic.php?t=35255


Oh and did u check ur PM, i sent u a PM.





Here's the dyno graph...

[JavaJoe_2]

I have dyno results on here from before and after.....and the power increase is stupidly insane.

30whp diffrence peak, and at 6k rpms, the power went down to 140whp with the precats, with the new system it stayed at like 190ish?

On a s/ced application.
You will not notice that much gain.
But, will experience some gain.

[Dawgz]

^ 30whp isnt noticable? or are u talkin about a N/A application.

[JavaJoe_2]

YOUR "Stupidly Insane power increase" is on a s/ced application.
He is NOT s/ced. And doesn't plan to be.
He will see nowhere near your gain.
He would be lucky to see a 5 possibly 10hp increase.

[CamryOnBronze]

I still dont understand a 30 whp gain from the precats alone... thats like the gain of the supercharger unit itself over stock.

[Midias]

I still dont understand a 30 whp gain from the precats alone... thats like the gain of the supercharger unit itself over stock.

He gained 30 whp from non precat headers a dat Y pipe and a highflow cat from magnaflow.

[Dawgz]

I still dont understand a 30 whp gain from the precats alone... thats like the gain of the supercharger unit itself over stock.

Like midias pointed out, that was from removing the pre-cats, the stock ypipe which in itself is a horrible ass design...just check the part right before the Cat...check out how thin the pipe gets!, and then also the Cat.

Im not sure which was clogged, the pre-cats or the cat...or both...but something was done and needed to be taken out.

Midias graciously supplied me basically a bolt on cat that fit perfectly, i sent him pics of the ypipe's flane and how the tilt was, and he somehow got the counter flange to tilt and be able to fit perfectly.


but all in all, the whole exhaust system needed an overhaul...not to drift away from the original topic any more, i didnt know the guy wasnt s\c'd or was never gonna be sc'd...my bad.

[94CoupeV6]

Even NA you will get some pretty decent gains. A new exhaust on a 13 year old car is going to be something you will feel unlike an intake.

[TMMK Toy]

The big restrictor is the y pipe itself. Look at the factory one compared to a good aftermarket one, like JPP. Or even a newer 3mz y pipe which doesnt have that restrictive kink in it. I noticed a good gain when I replaced my y pipe. Still got a cat too, but its high flow