I just ordered my new 2005 GMC truck and a Radix kit for it.

My question is what pulley can I run for more boost and not run out of injector and not have any belt slip problems.
3.0 ect... ?

Also what headers are best for this setup I prefer Stainless Steal?

and what cat back do you guys think is best?, sound and flow.

Thanks for the help

 

I could be wrong but I haven't found a belt smaller than 110.5" and it works well with my 3.0 pulley, but anything smaller and there would be slip, in which case you would start looking for a different tensioner.....and as far as injectors go, a good tuner (person, NOT handheld ) can get enough fuel through your 43lb injectors regardless of what pulley you use.

Dynatech Supermaxx system is a good stainless header system, but I'd consider getting them ceramic coated to keep heat/tarnishing down.

I would recommend Magnaflow for a catback, but its personal preference.

 

Exactly. Coated will help with heat.

 

That is simply not true on a 04 and 05 truck. People are starting to see that the 04 and 05 do run out of injector much faster than the 03 and earlier. But he should be fine for a pulley step or two. Only way to know for sure is to get a custom tune and use a wideband.

 

I tuned my 04 with a wideband and I see 12.2 AFR at WOT. And there is PLENTY of injector left.

2004 silverado
3.2 pulley (8 psi) Voided my warranty on the supercharger though.
LPE GT-II cam

 

Once again, it all comes down to where you want your AFR. If you want AFR in the 12's then they are fine. If you want it in the low 11 AFR range they will not be enough. There is also the difference in engine size that must factor in. For instance, I run the 2.9 pulley to get into the 8 psi range.

 

I can run in the low 11's too....I just found that to be a little rich for my blood. 12.2 is still nice and safe.

 

There you have it... if you have a 5.3 you are good to go!

 

Acutally, I have done the same on an 04 6.0

Here is a thought for ya:

Have you checked your MAF? 440 grams of air is the max it will flow, after that you are depenant on Fuel pressure for added fuel. So, infact it is not the injectors that are running out, it is the fuel system that is running out. The larger injectors are only hiding the real problem. Once the heads are installed and I am on my way to the 500/500 rwhp 5.3 I will be adding a larger intank pump with my pump booster.

 

Back to the topic at hand here....I would suggest buying the Radix system, installing it with the stock 3.4 pulley and going from there. Plese do not just JUMP to a smaller pulley until you have felt the truck with the out of the box set up. For most, this is more than enough!