Headers and check engine lights on 2000-2002 Vipers

[GONABITE]

Dan great post and very informative.

 

[SUN RA KAT]

Dan -

I am thinking about getting a new Viper GTS soon and probably putting on the Sean Roe Supercharger System, about 5 pounds boost so the cast pistons don't melt.

For something like that, would you still think the stock headers are better, a toss up, or get aftermarket headers?

Thanks.

 

[RedGTS]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR> The problem is that the sensor is only checking the mixture on one cylinder. the result is improper mixture control and higher than normal emmissions. I know of several folks that had to have a 2000-2002 vehicle emission tested for transfer of ownership only to find they failed the visual and emissions part of the inspection because of headers.<HR></BLOCKQUOTE>

Dan, does this condition (moving the sensor to a primary tube and thereby avoiding the light, but altering the mixture control) also result in a loss of performance, as is the case with the light on, or is it simply an emissions problem (which may not be as big a problem in those areas that do no emissions testing)? Thanks a lot for the info; I am seriously considering headers, and this is very useful.

Ronnie

 

[GTS Bruce]

I have the cdi headers on an 01 with the probe in a primary tube.No problems at all.Cdi said they dynoed same vehicle with sensor in collector and primary tube and it made no difference.The sensor on cdi goes into the center primary tube.If the car is running ok on all cylinders to begin with then there are no problems. Bruce

 

[Ulysses]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>The sensor on cdi goes into the center primary tube.If the car is running ok on all cylinders to begin with then there are no problems. Bruce<HR></BLOCKQUOTE>

And if an injector goes bad or the mixture goes too lean in another cylinder other than the center primary?

Dan,

I will be giving you a call on those quick fire O2 sensors. I've been looking for just that kind of solution since I first learned of this problem.

 

[Bugeater]

Why doesnt someone solve the problem from the other end...like change the parameter or values the ECU is looking for to set the code? Doesnt the Mopar ECU do this? (and probably the ONLY thing this computer does well)

I cant believe there arent more computer tuners out there to fix this...

 

[GTS Bruce]

I would love to move that sensor down to the collector.Computer program change,faster light up sensor.Keep me and all the others informed.I'm more worried about that one cyliner going rich and the computer leaning out the whole bank.What does molten aluminum smell like? Bruce

 

[SneakyPete]

I had made the same decision that Dan has in this post.

I had talked to a local tunner and he told me it was not worth the money because:

I had 2001 GTS, wanted headers and cat back from borla. Because newer cars come with the mopar shorty header version and the camshaft on these vehicles, adding after market headers would only gain you about 10 HP or so, and at $1250-3200 per set of headers you were better off getting other performance gaining items. Plus the check engine light and running rich was another deciding issue.

I am lucky the tunner I use is stand up and just doesn't want to sell his products to make money. If it cost $1250-3200 and only makes minimal HP why bother.

 

[red98GTS]

Dan....question here....if the 2000-2002 model Vipers don't respond as well to exhaust mods (headers) as the earlier cars, then how is it that CORSA got 18 rwhp and about 35+rwtq increase by just adding their 3" catback system on an otherwise stock 2000 ACR with no headers? I'm reading this off their site, which you have no doubt seen including their dyno sheets. Hmmmmm. And can we also assume that if this is true, that the same system on an earlier car, say a 98, would give even more?? What's your take on this....pete the ex glass guy and hot rodder

 

[Steve 00RT/10]

I am going to add my 2 cents(maybe 1 cent) to this thread. It is my (basic)understanding that the computer in the viper functions basically the same as any other OBD2 ECU. With the factory positioned front O2 sensor, it senses the entire bank and tells the computer to make corrections. However, it does not richen or lean a single cylinder. It takes all 5 collectively and adjusts the mixture to the entire bank to meet the programmed criteria. In other words, you could have a dirty injector, faulty injector, or some other injection problem, and as long as the mixture wasn't more than a 20% or so correction, it wouldn't set a light. Conversely, you could have a cylinder running way rich with the other cylinders running fine and the corrected mixture would lean out the entire bank just to fix the one running rich. The sensor has no way of identifying a particular cylinder, so adjusts the entire bank. It would take a sensor per cylinder to adjust individually.

Race cars run no O2's at all and are run at extremes continually. If there is a better sensor out there, I will move the O2 back to it's original location as I agree this a better place. In the mean time, my sources tell me the risk is very minimal.

As for the power increase, I picked up around 30HP. And then there's the sound....Belanger headers, no cats, 3" pipe, Walker Race buller mufflers......incredible! Makes the Viper sound the way it was meant to. I don't run heat shields and have had no problem in 10K miles so far. Side sills run much cooler.

Steve