I am trying to get an idea of what size core can be run behind rhe stock S4 front facia. All of your input is greatly appreciated.

Thanks

 

well ihave an s5 but i went kinda small cause i didnt want to cut the **** out of my TII. my over all size is 18.5"x 12.5"x 3" and i was able to put it behind everything so that i didnt have to cut the bumper at all.. im getting it piped in soon.. but that just how i did it

 

12 X 24 X 4 core size. I cut the horn brackets off and bought an air horn. It is mounted just behind bumper support (at the same height) in front of the round support that runs below the core support. The inlet and outlet are 2" below the frame rails and I made an aluminum bottom pan to keep the air where I wanted it, yes it is low but no lower than the subframe.

 

12x24 core 3" thickness 32" end to end, oh and it was 85.99 + s&h. Ebay FTW!

 

tinvestor-Do you mean 24x12x4?

What siize are your inlet and outlet?

 

yes and they are 3"

 

32x12.5x3

 

I was scoping out cores today on ebay to get an idea of prices and sizes available. There are so many different sizes to choose from.


Is 2.5" piping large enough if I was running a stage 1 or 2 hybrid?

 

As long as your exhuast is the same ideally you want nice even flow all throughout to prevent boost drop or back pressure. I have 3 inch everthing and some people it's 2.5 so it all depends really.

 

I am planning on running 3" exhaust. It will not have a cat or presilencer either. So, I am taking that 3" ic piping would be the better choice?

 

What kind of boost drop do you see?(how many psi?)

 

Boost drop is depending on several things size of the turbo,size of the intrcooler,amount and route of the piping. MOST people (incluing myself) usually see a EFFICIANCY loss anywhere between 10-20%. As for boost drop itself shouldnt be greater then 5 (currect me if I'm wrong). However if your intercooler is poorly made or incorrectly sized all it's going to do is heatsoke. And when that happens it's a whole nother ball game...lol.

 

When adding more piping and a larger intercooler you will create more lag? This is due to having to charge a larger cubic foot area? What size core do you think would be ideal for a stage 1 or 2 bnr hybrid?

 

not really,there is a big myth between "lag" and "boost response".Lag being the amount of time it takes for your tubo to make power at a desired level (psi). "Boost response" being the time it takes for you to get the acclerating effect.(currect me if I'm wrong I don't use these terms often) Given the size of your car I don't think you really will have an issue with either unless you're using a dinosour diesel turbo. As for core sizes I belive the norm (atleast for alot in the honda cummunity who are usually rocking T3/T4 hybrids or stock DSM turbo's is 3 or 4inch depending on the setup.