Exhaust Temp Numbers

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I'm racing Laguna Seca this weekend and needed to replace the full race exhaust with a more restrictive set up in order to make the 92 dbs sound limit. The new exhaust is definitely more restrictive and I expect EGT to rise but what is acceptable and safe EGTs for the Viper? I haven't come across any specific ranges for the Viper. Thanks

 

[Jack B]

Add fuel at wot, that will cool the mixture. In general high egt's are due to a lean mixture, not a restrictive exhaust. That is one reason the factory a/f starts falling above 5000 rpm.

I'm racing Laguna Seca this weekend and needed to replace the full race exhaust with a more restrictive set up in order to make the 92 dbs sound limit. The new exhaust is definitely more restrictive and I expect EGT to rise but what is acceptable and safe EGTs for the Viper? I haven't come across any specific ranges for the Viper. Thanks

 

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UPDATE: Car ran like sh*t. The Gen 1 mufflers were entirely too restrictive. The PCV valve under the intake manifold was releasing oil vapors and small amounts of oil and my oil catch can was smoking as well. Far too much back pressure for the motor. Got a grand total of 3 laps. Back to the drawing board.

 

[XLR8]

Jonathan Are you going to put the old exhaust back on the car and see about the blow by without the restriction? To get to run at Laguna and have that happen is ........ I cant even think of the words to describe it. Tim

 

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Yep, that is exactly what I am going to do. First I am going to remove the Gen 1 mufflers and leave the hi-flow cats on to test that portion while I have the side sills off. If that goes well, then I will put the full race exhaust back on to see how it end s up from there. I need to solve the dbs level for the exhaust as I'm missing too many track days at Laguna Seca. Yes, it was very disappointing to drive 7 hours round trip for a total of 3 laps.

Jonathan Are you going to put the old exhaust back on the car and see about the blow by without the restriction? To get to run at Laguna and have that happen is ........ I cant even think of the words to describe it. Tim

 

[XLR8]

Do the Gen 1 mufflers have some kind of chamber in them? If not then the cats probably have more restriction than the mufflers.

 

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Tim, I'm running the 3" Random Tech Hi- flow cats. These are the identical cats that most run that have bigger motors than mine. The Gen 1 mufflers were pretty narrow when I looked through them. I'll take pics when I pull them off this weekend.