Smeding Diesel S300 Custom drop in replacement options for the 03 to 07 Cummins.
Please choose your Exhaust housing, Turbine wheel and Compressor wheel.
If you have chosen a option that will not work it will show with no price, this means that turbo is not available.
This turbo will not use the factory wastegate control valve on the 04.5-07 trucks, so tuning is needed or some kind of boost fooler.
12cm Vs 14cm
The 12cm housing will be faster spooling but will get hot after long wide open throttle pulls due to the size, The 14cm housing will be a little slower spooling but will handle wide open throttle situations better. The 12cm housing is only available on the 65mm and 68mm turbine wheels.
65mm Vs 68mm Vs 73mm
These numbers reference the size of the S300 turbine wheel (exhaust wheel) , we offer 3 different sizes as you can see: 65mm 68mm and 73mm.
Bigger is not always better, its best to choose the proper size wheel for your application! Bigger the turbine wheel, the more energy needed to move it.
The 65mm turbine wheel will be the fastest spooling but will not support much over 500 hp. The 68mm turbine wheel will be a good all around size for anyone wanting 400-550 HP but will support up to about 600 HP and the 73mm will be a good set up for some one looking to drive the truck agressivly and is looking gor the most out of the S300 frame turbos, this 73mm wheel will go to about 750-800 HP.
Compressor wheel references the size of wheel where the air comes in at, this is the wheel that you see facing you in our pictures. We offer a very large variety of wheel sizes to fit all different applications, our smallest S300 wheel is our 62mm wheel, and our largest S300 frame wheel is 72mm.
along with choosing a turbine wheel, choosing the proper size compressor wheel is very important.
The 62-63mm wheels like to be around 400-550 HP these wheels are kinda the catch off of compressor wheels because they perform great at 400-550 HP with minimal lag, this is a common place for most 5.9L cummins to end up because with just some tunes and a turbo you are easily 500 Hp or more nice daily driver/ tow set up.
Next size up is the 64.5-66mm wheels, these wheels usually require a some extra supporting mods to really enjoy the power they are capable of. Most customers with a S364.5 or S366 are around 500-650 Hp and have a few supporting mods like fuel upgrades. These make good daily drivers but you start losing the ability to tow with them because the power comes in rather harsh and some what late in the RPM range.
69 and 72mm, these are the largest wheels we offer in the S300 frame. These turbos can be use on light street trucks and racers. The turbos are happy at 600-750 Hp and enjoy wide open throttle pulls!