Hi,

Started at looking at upgrading my exhaust system. However, after reviewing what I have, it looks like my catalytic system has been removed, and these G pipes from the header go straight into the cans. Correct? Any one seen this before? Fortunately no smog tests here.

 

No. Can't wait to find out. Looks oe.

 

You're in great shape. At the most, just open up your present cans and clean them up inside. Should be a very nice, efficient system when you're done.

 

Looks OEM and very efficient; now you will make everyone want one.

 

Hard to tell from the picture, but it looks to me like each heat exchanger is directly connected to the muffler with no crossover between the left/right cylinder banks. An exhaust system like that is good for race cars, but will lack midrange power and torque for normal daily use.

 

Not sure about that. The immediate bend and then the 90's into muffler should create enough back pressure to do well. Without knowing what cams and if fuel system is upgraded, it's hard to say it's lacking low end grunt.

 

I am no expert on this subject, but people like Steve Weiner from Rennsport Systems is, and according to his input on other threads on this same subject, street driven cars benefit in the midrange from a crossover between the cylinder banks at one point or another, either in the 2 in muffler design, or the pipes converging before they enter individual mufflers.
I do put his opinions and knowledge in very high regards.

 

Steve's more than versed and very knowledgeable on most things we inquire on. I am by no means the guru of exhaust efficiency, but do have a little understanding of how it works. The scavenging effect of backpressure, or lack of, does not necessarily mean low end torque is reduced. There are few more factors involved and I was just trying to help OP.
Actually, the mixing of both sides/pulses has little to do with performance and more to do with esthetics. If properly mixed in a good chamber, it just makes for a smooth even idle. As opposed to two 3 cylinder engines.

 

Interesting cat bypass design. Your catalytic converter has been removed and a bung on the G pipe installed.
Do you have an O2 sensor on the other side G pipe? You are lucky to have no smog test and your performance will be improved.

 

So no one recognizing the option? Where is Bill?

 

Looks very similar to my BB cat bypass.

 

No O2 sensor connected at all. The other side is just a G pipe with no bung. (I think the Bischoff had only one, this is an early 96 Var.) I can't even find the O2 Sensor. I need to put the car on a hoist to have a good look around.

I was looking at installing a x-pipe, but now I am wondering whether there is an advantage over this system. I am surprised to date that nobody has seen it before, is it really bespoke!

 

The benefits you might gain with an X pipe would negate the current benefit you have, of the most direct exhaust. The extra piping needed to get the system to be connected with an X pipe and adjacent plumbing would most likely reap less power across the board. If your car had a full exhaust system and then you added an X pipe, you "might" see a small increase, if any. Keep what ya got and enjoy. Maybe mod the cans if they're stock (internally). Aloha

 

I like the G-pipe setup and think the performance would be similar to an X-pipe without a Catalyst.
The bend radius on the G-pipe looks about equal to the X-pipe radius ... see the photos below.
The main difference is about 2 feet of additional pipe on each side before entering the mufflers.
I would recommend that you locate the O2 sensor and connect it to the threaded bung.

 

Ted, the O2 sensor besides CEL, does it give info back to the engine management system?