Any photos of exhaust with dual outlet resonator?

OldZofTorC

Registered User
I have a borla two outlet resonator. I want to have this installed so I can drive the car without fear of blowing a head gasket. I have looked through the archives but not much there.
 
Changing the resonator will not do anything to help your head gaskets. They blow due to time, torque to yield bolts, electrolysis in the coolant, detonation, or overheating. A freer flowing exhaust will help performance, but if you are concerned about the head gaskets blowing on you, you would be better off just replacing them now, getting the heads checked/resurfaced, and using ARP head studs to put it back together.
 
A lot of threads and faqs on this forum also point to our exhaust ...specifically the resonator as a bottle neck causing high psi and hg failure...especially if overdriving. I went with arp studs and was planning exhaust not only for performance but it looked like a hg safety precaution.
 
A lot of threads and faqs on this forum also point to our exhaust ...specifically the resonator as a bottle neck.

I was thinking its more on the line of the manifolds not being big enough, thats why they are commonly ported. They are smaller than the exhaust opening on the head and restricting air flow there, I haven't read much about the resonator being the problem.
 
Last edited:
That is unfounded speculation. There is no evidence that exhaust either causes or saves head gaskets. If you want to keep them intact as long as possible, make sure your cooling system and ignition system are in good shape, make sure you don't have any vacuum leaks, don't over-rev the motor, and always run premium fuel. If you don't know the history of the car or how it was maintained, and you need it to be dependable, my advice at that point is to do them yourself so you know they were done right. As for what gaskets to use, felpro either way, and mls gaskets are nice, but unless you are going to have the block and heads resurfaced to the right roughness, just order the ones for an SC.
 
Don't judge me on the exhaust; I didn't bend/weld it up. I do plan to weld up a more aesthetically pleasing system, though it will likely be the same configuration. Hopefully these pictures help.



 
Last edited:
Looks as nice under as it does above - I hope you sent the 2nd image in for the calendar :)
 
A freer flowing exhaust yields less heat especially in the heads. So it will help in general. Do not replace headgaskets until needed. You need to open outlet on manifolds. And 2" or 2 1/4" down pipes to resonator. Then....


Changing the resonator will not do anything to help your head gaskets. They blow due to time, torque to yield bolts, electrolysis in the coolant, detonation, or overheating. A freer flowing exhaust will help performance, but if you are concerned about the head gaskets blowing on you, you would be better off just replacing them now, getting the heads checked/resurfaced, and using ARP head studs to put it back together.
 
A freer flowing exhaust yields less heat especially in the heads. So it will help in general. Do not replace headgaskets until needed. You need to open outlet on manifolds. And 2" or 2 1/4" down pipes to resonator. Then....

This article touches on exhaust temps and measured pressure. I don't have a frame of reference but per the author the 15 psi back pressure our stock exhaust creates is way too much. I hogged out the outlets on my car but still need exhaust work.
http://www.sccoa.com/articles/cwexhaust.php
 
Thanks guys!

Those pictures are very helpful and the car looks awesome. Those are some monster sway bars. I should have mentioned mine is a 95 but have seen that this year should be even easier. The car has not had a nut turned on it yet besides tranny rebuild with 2k torque converter and the overdrive on the blower. The car has only 45k. I have been very cautious with it because of the HG stories. Should this set-up as it is now be able to break the tires loose from a standing start? I will do a coolant flush and Check the spark plugs.
I have only had the car for a couple of thousand miles.
 
Mufflers

I see you are not running mufflers. What is the sound level inside the car? I was planning to start slow and just have the resonator and separate outlets with stock mufflers. I was hoping to stay pretty stealth.
 
Those pictures are very helpful and the car looks awesome. Those are some monster sway bars.
Thanks! Those are ADDCO 1-1/4" sway bars.

I should have mentioned mine is a 95 but have seen that this year should be even easier.
While the car pictured above is a '90, that is a '92-97 fuel tank, so you'll have the same routing/space to work with on your '95.


I see you are not running mufflers. What is the sound level inside the car? I was planning to start slow and just have the resonator and separate outlets with stock mufflers. I was hoping to stay pretty stealth.
The "resonator" is in fact a muffler. It's a straight-through crossover design, but it does reduce the sound level. Between the cats and the mid-mounted muffler/resonator, it's aggressive, but not overly loud. Here are a couple of videos. Keep in mind, this car isn't a V6 anymore.

In-car video of a pass at the '12 SC/XR7 Shootout:
http://s6.photobucket.com/user/racecougar/media/90 XR7/Shootout 2012/Shootout2012run2incar.mp4.html

Exterior video of two pulls at a local dyno in '10:
http://s6.photobucket.com/user/racecougar/media/90 XR7/DynoRuns5-20-10.mp4.html
 
Thanks for the response

Should this car be able to break the tires loose with the stock set up?
I have tried with a rolling start and they will start to break loose at around 4k.
My girlfriend had an SC years ago. I thought it was stock and I think it would break em loose with no problem.
 
As far as i can tell my 94-5speed is stock with a tiny resonator that almost fits in the palm of your hand and it will break loose and go sideways from a 10-15 mph roll.
 
As I suspected

I have always suspected something was amiss. Must be the stall converter. Softer from a stop but comes on real good after about 3k although I haven't really been watching the tach. I am in a small town but we have townies, counties, and staties, so I have to keep it down and an eye out for these guys. I don't want them to mark me, the car does stand out.

I have an appointment Tuesday to have the Borla installed. I am pretty sure I will go straight out from there with the option of adding mufflers if it is too loud for me.
 
Back
Top