I actually installed magnaflow Resonators to kill the drone.

 

scott, do you think the cel is a result of the droning? When I first purchased the car, I drove all the way from Santa Maria to San Mateo CA with no problems what so ever. It was a total of about 3.5 hrs. It's after I did the exhaust pipes to 2.25" all over, removed all resonators, kept the stock mufflers, converted the stock "y" to "h" pipe, drove probably over 100 miles within a few days, and then the cel comes on all of a sudden. I also kept all the cat's on too. The car drives fine and I don't notice any issues but the cel being on. I know it has to be related to the modified exhaust. I'm going to have to drop by Kragen tomorrow to purchase an obd2 diagnostic computer.

 

I doubt the drone would do this. I did a full exhaust Headers/2.5" with magnaflow cats resanators and mufflers. I made sure to put the 02 sensors back in fromt and behind the cats and it never threw a code. My car is a 97 so not sure if that matters.
Here was the thread way back then.
https://www.clublexus.com/forums/per...tart-pics.html

 

Thanks for the pics. Helps a lot! Looks like yours has the xpipe. Everything is pretty much the same setup like mine, except for the cats and x pipe. I still have the cats in the original location. At the x pipe section, mine has each pipe going straight to the cats. Maybe that's what I need to fix. I may just buy a x pipe and have the muffler shop weld it on.

 

Does anyone know around how much it would cost at a muffler shop to have a exhaust tip welded on? not really looking to do it soon but the thought crossed my mind... also i know theres a name for it just cant think of it right now but are there direct bolt on replacement straight pipe for the two CATs off of the manifolds?

 

thanks for backing me up. 2.5" is just right for good performance on engines that are about 2 liters of engine size. take a 1uz with its mighty 4L (basically like 2x 4cyl of displacement) and dual exhausts with 2.5" piping is a perfect scale up.

only problem is at a good size for performance you may not get the best sound, which is why I've found that the larger exhaust with a resonator yields the best performance and sound at the same time. removing your stock resonators and doing nothing else is just a cheap way to get that sound out of the smaller pipes, but the performance is not there.

 

Why did you not include the S&S Headers in your list?

 

After reading did we come to agreement on the 92 sc400 exhaust California car. Can we cut out the center cat and replace with a x-pipe and not throw a code. Mike

 

anyone know the pro's con's of an x pipe vs an x crossover?


PN 10780
http://www.magnaflow.com/02product/d...rtnumber=10780


PN 10790
http://www.magnaflow.com/02product/d...rtnumber=10790

 

Here's a question if anyone has considered it :

Any results with removing the dual cats off the manifolds - running the large diameter pipe off the manifolds (2.5 - 3" ?) to a single 3" high flow cat rught under that large center heat shield (a new 3-way style to keep it emissions legal) - then split 2.5" duals to a pair of some type of mufflers ?? - I'd lengthen the O2 sensor wires to keep them on the downstream side of the cat and keep the computer happy.

Only reason I'm thinking of this is that somehow I don't have the US emissions setup on our 93 - I couldn't make it pass emissions here in Houston no matter what I tried - the original cats are old (250kmi) and aren't the new type that make it pass the test - the cat heat will basically be removed from under the hood and floorboard towards the rear (don't know if there's a bad side to that) - heat is a big issue here in hell

Worst choice I can see ahead of me is what brand cat and mufflers - anyone have any input right off?

 

This one will give you the equalization without much disturbance to the flow

 

Is equalization good? what are the benefits?


also this topic really should have much more attention

 

X-pipes work on the principle of scavenging

What I mean by that is exhaust is a pulse, it's not a constant flow like a sink. So as it pulses, if it merges at the right point, one pulses moves right in line with the next pulse and they actually pull each other down towards the tail pipe. The result is it's easier for the motor to move exhaust out and you gain a few hp.

 

notice how the inlets and outlets are pointed differently, for the exhaust of an SC where it starts wide goes narrow and wide again, I would try the angled one which would be the X pipe. both work on the principles of scavenging, just in a little bit different angles and may have a little bit different sound to them.

 

sorry to bring this back. are there still no catbacks for the sc400? how much would it cost to have a custom exhaust made or the cats gutted or whatever people do? i would like an x pipe and all the resonators deleted. can i just cut the resonators and cats out and replace with some straight pipes? if so what's the thickness and any DIYs on that? i have megan tanabe axle backs already, just wanna go all out though and sound like a monster cz i can lol.