Alright so i am thinking about doing a build on my 05 Coupe with the auto trans (i know i know its an auto but future is going to leave the car in the family but to someone who cant drive stick) that being said i plan on doing forced induction more then likely a supercharger kit from stillen but im going to go from a used motor or long block and do all the mods outside then put it in my question is whats the difference between the HR block and the DE block would the HR block be better for forced induction or would it even make a difference if im going to change out the intake and heads so i guess is the HR Block stronger then the DE if i run 100 mm bore. Thanks to anyone and everyone for any help or advice in advance.

The HR block is different from the DE block and they are not interchangeable from what I have seen.

The auto trans can handle about 350 or so hp, some get around 400hp, but you need a tranny cooler and a valve body. The DE block can handle about 400 hp with stock components so you don't need to build it with a Stillen or Vortech supercharger.

I used to have a Vortech on my 04 coupe but it had a manual tranny. A friend had a Vortech on his 05 with an automatic and had to have the tranny mods done.

Thanks for the info the plans are coming along time to start buying parts now

Correct you don't need to replace the engine or internals if going with a Stillen or Vortech supercharger. HR has higher compression so it would not be good for going with high boost on either a turbo or blower. But a DE can handle more boost with stock internals. I can PM you prices for either one systems, feel free to message me if you have any more questions.