I have a buddy that owns a 2001 Silverado 1500 Z71 5.3L....I was wondering how much RWHP you guys might think he's putting down. He's got:

Stock exhaust manifolds and cats, but has no muffler and turns down before the axle.
Underdrive pulley
K&N cold air kit
AIR AID TB spacer
Descreened MAF
TB bypass mod

That's about it. I saw someone on here with similar mods on there 5.3 and they dynoed 250ish. My buddy thinks he may be making more than that. So what do you guy think he makes?

 

ttt.....Come on any of you guys have any idea?!

 

250-265 rwhp.. those mods do close to nothing.. except for the underdrive pulley...

 

So would everyone else agree about 250-265 rwhp?

 

I would say no more than 250 unless his is running very strong. Honestly, I would think it would be closer to 235-245.

 

60032 rwhp. 245 260 ish

 

so maybe I missed something a year or so back but I know in 72ish they started rating the engines at the rear tires. prior to that it was crank hp. so isthe factory now rating them at the crank again? I ask cause I seem to recall seeing 285 to 290 hp listings in the ads I for some reason thought this was rear tire hp...
help
Dave

 

From what I understand now, the factory rates them by the flywheel horsepower. For example, LS1's are rated 350 from the factory. Which is right for the flywheel. They make around 300 at rearwheels.

 

240...

 

How much rwhp do you think Ceramic coated midlengths and ORY or high flow cats would net him? About 20 more I say, right?