Backfire between shifts

[c4zr1]

I have a corsa exhaust system on my ZR-1 and it backfires between shifts or when I let off the gas after getting on it some in the lower gears. My question is should I get the corsa exhaust system welded up. I installed it using corsa's wide pipe clamps. All stock except corsa exhaust and a Haibeck chip.

[Kevin]

hum, that doesn't sound right. I can't remember the car I drove with corsa's on it doing that. When I talked to mark last about doing a chip fo the exhaust he said it shouldn't be necessary as the exhaust alone shouldn't cause a problem

[mike100]

Mine pops from time to time when the engine is cold.

[GOLDCYLON]

Have you done any top end porting on the car? If you did you get the chip asjusted?

[FU]

It can be easily fixed with a chip change. Talk with your chip tuner.

[XfireZ51]

Where is the popping occurring? Up front, mid or at end of exhaust? Could indicate air leak. Unburned fuel/air ignited by fresh air. At decel, the high vacuum will suck air into the exhaust causing ignition.

[c4zr1]

The popping occurs out the exhaust tips. I never have really liked the corsa clamping even though they are the wide band type. I may just try and get the system welded up. Just got to try and find a shop that will do a good job. Just wondering if it can be welded in place.
When I had Mark do the chip he knew the car was stock except the exhaust.

[FU]

When I had Mark do the chip he knew the car was stock except the exhaust.

Ok then read Dom's post (X-Fire).
Do you have cat's ? Also did you tell Marc that you do / not have cat's ?

[XfireZ51]

The popping occurs out the exhaust tips. I never have really liked the corsa clamping even though they are the wide band type. I may just try and get the system welded up. Just got to try and find a shop that will do a good job. Just wondering if it can be welded in place.
When I had Mark do the chip he knew the car was stock except the exhaust.

I found that the wide bands stretch over time and lose clamping force. Plus the clamping force is spread over a wider area and doesn't really seal well. I was tuning my 84 Xfire and for the longest time, I needed to keep adding fuel to the low MAP area of the VE table which is primarily for decel. Finally, I found that the passenger side muffler was loose. During decel, air was being sucked from the rear and I was getting popping. The fresh air was actually making its way upstream the exhaust through the cat and affecting the O2 sensor so that it was showing the motor running lean. Once I clamped the muffler, the ECM began pulling fuel back out from the same area.

[c4zr1]

It does have cat's. Should I go to an x-pipe?

[Jim Nolan]

When my motor was stock I had a corsa cat back and it never backfired. If Marc did the chip there must have some missed communication between the two of you. Contact him about a re-tune of the e-prom. I had no trouble with the clamps that came with the system. You might regret welding it all together at a later date.

[c4zr1]

I sent Mark an email, but have not heard anything from him. Maybe someone here on the web lives close to him and can mention my problem to him.

[Kevin]

I sent Mark an email, but have not heard anything from him. Maybe someone here on the web lives close to him and can mention my problem to him.

when did you email him?

[c4zr1]

I sent the email Monday to 'mhaibeck@sbcglobal.net'. Is this still a good email address?

[-=Jeff=-]

I sent the email Monday to 'mhaibeck@sbcglobal.net'. Is this still a good email address?

Yes that is a good address still