Bottommount VS Topmount
 

First of all, i've always build/ driven driftcars so this is a bit of an new area for me, as I drove rotary powered machines.

So this might be a newbee question, but why is bottommont manifold so popular on Evo's? Why not topmount?


Nikolaj Povlsen // Denmark (sorry for my english)

Might have something to do with Short Vs Long Runners or because most company's only offer the bottom mount turbo kits, me personally, I like Top Mount, why? Because Cool!

I'm gonna guess, availability and that most aftermarket downpipes, o2 housings are for bottom mounts. A top mount is going to be a custom deal most likely which means more $$

its acutally just a design thing most evo companys make bottom mounts and only offer them becuse thats what sells well there were a bunch of companys that use to make top mounts for evos peakboost asap performance to name a few for hondas they are super popular they just never took off for evos.

Most EVO guys don't want to buy a turbo kit. They want to upgrade one part at a time. Thus you need a manifold and turbo layout that will work with a stock replacement downpipe, turbo inlet and IC piping.

On cars like Hondas where they aren't turbocharged to begin with, most people typically buy a "turbo kit" that interfaces with none of their N/A parts so it's free reign on the design.

IMO, top mount allows a better collector design with standard rotation turbochargers as the turbine input is further away from the motor. You don't have to point the header pipes back towards the motor to make it into the collectr like you do when using a bottom mount setup.

Also, forward facing setups are pretty popular in the EVO world. Most that would be willing to spend the money on a "kit" that won't work with any of their stock replacement parts are likely looking for 600+ HP and want to go forward facing.

When I was going front facing I inquired about top mounts and I seem to recall the conversation going something like it would cost a lot more then standard config or ff and there would be absolutely no performance edge.....so no real logical reason to do it.