I have a 98 Z28 A4 with 90k miles is a 100 to a 150 to much for it?

 

Check your compression and see if the fuel system is up to par. I put nitrous on mine with 100k miles. I'm jetted for a 100 shot but if my injectors can handle it (dry shot) I'll jet it for 125.

 

my friend has a 150 shot on his 110k mile stock motor and i thought that is crazy but just
checking thanks for the info

 

It really comes down to how the car has been maintained. You can do a compression test and make sure all as well.
a hundred thousand miles should not be a problem.
Dave

 

You shouldn't have a problem with the motor holding up. Like the others said, as long as you have a healthy motor....Spray away...

 

Its really all about the motor and the overall condition of it. I have a 2000 Camaro SS and it has about 119k miles on it. I just installed the TnT kit about 2-3wks ago and am spraying a 100 shot. Hits hard as hell and put me from a 12.8 to a 11.91@119mph. Id do it.