Top-Mount vs. Bottom-Mount

[Dopefish]

I have seen several differant turbo manifolds offered for the KA but the big differance between them all seems to be how the turbo is mounted.

I searched but didnt pick up any posts comparing these two, so with that I ask...

What are the pros and cons of top mount turbo kits or bottom mount turbo kits?

Thanks,
~Kris

[s13dan]

On SR's i know the only real advantage from a bottom mount is you can still use bolt on turbo's,turbo lines o2 housings, and downpipes, but for anything custom i imagine its all about prefrences issues with room in the engine bay and how easy you want to make the turbo set up to work on. Top mount i would say is easier to work on.

[breakindrifts]

Top Mount Pro's: Looks better, easier to work on turbo
Cons: Piping is harder to route, cops can easily spot it, less clearance with MC

Bottom Mount Pro's : Stealth, easier to route piping to/ oil lines, more clearance.
Cons: Doesnt look as cool, harder to reach turbo parts for servicing.

Personally I like Bottom mount.

[Dopefish]

Hmm, I'd be concerned about the MC but policia dont bother me. I like the ease of servicing a top-mount looks to provide, although some fo the bottom-mount headers are almost artistic.

I guess in my situation it really would just be preferance.

~Kris

[pr240sx]

Well, you can fab a side mount and have the best of both worlds.
You will have limited space for turbo size though.
I prefer (and have) bottom mount. Is cooler (temp wise) and easier to route piping. I dont fiddle too much around the turbo

[NemeGuero]

It is all just preference. Research mani's before you buy and some will advertise the clearance they offer for the BMCs. This was the ONLY issue I had with my JGS mani (CRAP). ETD gives great clearance. (both are top mounts)

Bottom mounts are cool 'cuz you can keep the turbo "hidden."

I doubt side mount would have enough clearance unless the exhaust runners were like..... 1" long.

Why would bottom mount be cooler temp wise? heat is heat, the turbo, manifold and downpipe all generate heat no matter where they are.

If you go top mount, you can do the hood washer trick and cool everything off better than if you had a bottom mount. Or cut a vent or louvre panel.

[blue109]

i have a top mount on my SR. its pretty close to the MC, and ive seen my friends car melt one before, but i made a simple sheet metal heat shield and covered it with some of that thermal barrier material, and it stays pretty cool. not much hotter than stock.

and it looks sweet:)

[BigVinnie]

Bottom mount manifolds can tend to have crazier runner designs, since there is more room from deck heigth to engine mounts to play with. Ivan utilizes the bottom mount manis to make some crazy off the hook runner designs.
Most top mount designs I have seen are plain, and runners cant get to crazy since there isn't much room to play with from the head to hood.

[pr240sx]

Cooler because is more exposed to air circulation amd downpipe angle is less aggressive.

[NemeGuero]

I'll give it to you for the downpipe angle, but I doubt top mount vs bottom mount experiences much difference in air circulation.

They're 5-6" height difference? And like I said, if you do the hood trick, you get more air flowing out across the top of the turbo on a top mount.

[killjoy]

Top mounts allow for bigger turbos and the more efficient runner designs make more power.

Period.