Backfire between shifts - ZR-1 Net Registry Forums

c4zr1 · 02-25-2012

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 · 02-25-2012

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 · 02-25-2012

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

GOLDCYLON · 02-25-2012

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

FU · 02-25-2012

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

XfireZ51 · 02-25-2012

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 · 02-25-2012

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 · 02-25-2012

Quote:

Originally Posted by c4zr1

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 · 02-25-2012

Quote:

Originally Posted by 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.

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 · 02-25-2012

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

02-25-2012	#1
c4zr1 Join Date: Nov 2005 Location: Amarillo, Texas Posts: 47	Backfire between shifts 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.

02-25-2012	#2
Kevin Join Date: Jun 2005 Location: pittsburgh Posts: 4,633	Re: Backfire between shifts 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 __________________ It's not the car, it's the people - Doug Johnson 90 r/r "KEYS ON" nick named "T.L.B"

02-25-2012	#3
mike100 Join Date: Feb 2011 Location: San Marcos CA Posts: 1,802	Re: Backfire between shifts Mine pops from time to time when the engine is cold.

02-25-2012	#4
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,154	Re: Backfire between shifts Have you done any top end porting on the car? If you did you get the chip asjusted? __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V

02-25-2012	#5
FU Join Date: Mar 2004 Location: Found Member Posts: 4,346	Re: Backfire between shifts It can be easily fixed with a chip change. Talk with your chip tuner. __________________ Frank Urbo. NCM Lifetime member # 982 Registry Founding # 237

02-25-2012	#6
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,690	Re: Backfire between shifts 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. __________________ [SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX

02-25-2012	#7
c4zr1 Join Date: Nov 2005 Location: Amarillo, Texas Posts: 47	Re: Backfire between shifts 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.

02-25-2012	#10
c4zr1 Join Date: Nov 2005 Location: Amarillo, Texas Posts: 47	Re: Backfire between shifts It does have cat's. Should I go to an x-pipe?