Hi everyone,

I have been reading various magazines that have articles that deal with recent findings on installing after market exhaust and header systems. Granted, these articles deal with this procedure and its effects on exotic cars, such as Ferrari.

In these articles, there are concerns expressed about engine damage as a result of the after market exhaust changing the airflow dynamics and that of other systems, originally set at the factory. It was suggested that the car may run improperly, change timing, etc. The link below will explain it better, as far as a Ferrari is concerned.

http://www.newsferrari.com/experience13-8.html

My question is: Could this same issue mess with our Vettes? Could, over time, the engine be damaged? I would love to change my stock exhaust over to some decent headers and upgraded exhaust (for performance and sound, of course), but don't want to do it if there are negative long term effects.

Too many electronics these days to muck up perhaps?

Thanks!

Paul

Normal driving with headers still requires the oxygen sensor and the computer to work around 14.7 parts of air to 1 part of gasoline. When you stand on it the closed loop of info and computer switches to a look up table with about a 12:1 ratio. I can't see headers leaning that out enough to be of concern. On top of that I have read that retuning after headers is done to actually lean out the 12:1 a bit for even more power. I don't think there is reason for concern.

My daughter has had a Borla system on her 94 25th Anniversary Trans Am (LT1 engine) with no ill effects. YMMV, but she's had no issues and it sure sounds great!

I have a Borla system on my 06 C6. The only complaint I have is some resonance around 1600 rpm. The factory suggested inserting venturis into the pipes prior to the muffers. Borla supplied the venturis. Has anyone tried this and did it resolve the resonance?

Venturis sound like restrictions to me.

Installing the venturis does imply adding some restriction to the exhaust system - I won't install them until I hear from someone who has tried it before me.

Which Borla's do you have on your c606? I have Stingers
and there is no resonnance just a fine sounding burble when you let off accelerator. Is it this 'burbbling' or more like buzzing you hear. If buzzing assume you have checked all the installation pieces on connection for correct torque and hangers locations.

It's not a buzzing but more of a low frequency drone when at 1600 rpm's, it goes away when the rpm's climb or drop from 1600. I plan to check the hangers when I get it up on a lift.

Every vehicle leaving any assembly line has gone through a precise design process to maximize intended performance while meeting regulations for mileage and emission standards.  Of course new exhaust, Air Intake, wheel size, etc. are altering this balanced design configuration with after-market stuff.  

A venturi is designed to change a pressure-head to a velocity-head in order to maximize air flow for combustion.  Same amount of air but altered results.