A thread with all the various belt/pulley setups.
Here is what I've got so far...
For the RADIX on LS1 Based Engine 4.8/5.3/6.0
Pulley= Belt Length-------Gatorback Part #
2.75 = 110.5-------- 4061105 or 6PK2805
3.00 = 110.5-------- 4061105 or 6PK2805
3.10 = 111.5-------- 4061115
3.25 = 111.5-------- 4061115
3.30 = 112.0-------- 4061120
3.40 = 112.0-------- 4061120

If everybody will send me their pulley/belt size I will put the info together.
Last updated: 26 Oct 06

 

Someone needs to correct me if I'm wrong but I think all the brackets are the same for the 4.8,5.3,6.0 so the belts will be the same with corresponding pullies. I think I have the 110.5 on my 3.0 with 4.8.

 

5.3 with 3.0 pulley and aftermarket alt with smaller pulley = 110.5
5.3 with 3.4 and stock alt = 112.0
5.3 with 3.4 and aftermarket alt = 111.5

These are the different configurations that I have run, all of them worked without belt squealing during WOT shifts. The 110.5 that I have now is very tight (took some work to get it on), but it works well.

I believe you are correct.

 

i have a 6.0L with a 2.8" pulley and am using a 110.5 belt

 

The bracketry is the same, but you can get 2 different size intermediate pullies to take up the slack instead of changing belts all the time. The righthand pulley under the blower snout comes in either 90mm, or 100mm sizes. Or, you can go the Metco route with the billet ones (like Grippy did).

 

Well that would make the chart even less complicated since all 3 engines have the same pulley geometry. I can just list belt sizes for pulley's 3.4" down to 2.75 or so. If you swapped to aftermarket pulley's or different Alt then you could adjust using the chart as a baseline. Keep the info coming in and when I get enough I will edit my 1st post and put all the info in one spot. Maybe Blown Chevy could list the sizes that come with the different kits

 

I'm betting that all the later model trucks with the 4.8 5.3 6.0 Combination all have the 112" belt.

 

Doesn't the standard pulley size from Magnacharger depend on the motor size? I know the 5.3 gets the 3.4" pulley, but I think the 4.8 and 6.0 have different sizes. Someone correct me if I am wrong.

 

I run a 110.5"Gatorback belt with my 2.75" pulley with no slippage.

 

In the kit as it came from Magnuson.