Top or bottom mounted turbo?

[Hit_N_Run-player]

Is there really any advantage or disadvantage of having a top mounted turbo manifold http://www.stockreco.com/01sap.jpg or a regular bottom turbo manifold http://www.stockreco.com/picture1006.jpg ???

[Xtreme_098]

One on top ? No. One on bottom ? No. One on top and one on bottom ? No. Two on top and Two on bottom! Heh Oh Right.

[Partizan]

Doesn't really matter, might help if you have a crowded engine bay or something but no performance beneift.

[logik23]

Bottom mount hides it so you can fool people...lol.....whatever...

[AWDSR20]

i think it has something to do with the heat... a top one alows for better cooling and alows for a lareg turbo to be instaled ... whatever, i have the stock one and it looks rusty...

[Hit_N_Run-player]

i think i would get top mount, pop the hood and its like *BANG*, turbo's sittin there showin the beastness!!

[mynismo]

the main reason people do topmounts is for fitment. its usually too big to mount it in stock location.

[nissanfanatic]

The top mount gives easier acces to the turbo. Bottom mount allows for most of the downpipes made to be used. Top mount runs the risk of melting stuff in the engine bay.(i.e. brake fluid resovoir, wires, spark plug wires, just in general "shit").

[GT500916]

Originally Posted by Hit_N_Run-player

Is there really any advantage or disadvantage of having a top mounted turbo manifold http://www.stockreco.com/01sap.jpg or a regular bottom turbo manifold http://www.stockreco.com/picture1006.jpg ???

First question i want to know is, do you know what size turbo that is hes running there? the A/R on that or any info on that top mount turbo??

About the top or bottom mount, i heard that one can spool faster than the other, it is because the cooler the turbo gets the more lag you have.. as posted by AWDSR20 ... i remember reading that somewhere as well.

Turbos are ment to work off heat and pressure, hot air is prettu much energy for the turbo, if that air gets colder then it wont have as much energy. This is why its a good idea and some people do this , is wrap your turbo header with exhaust wrap to not let the head escape from the header and most of it goes in the turbo and spools it faster, so it slightly reduces lag.. I doubt its noticable, but if you compare chart im sure you will notice some different numbers if compared to top and bottom mounts.

I myself dont know which way ill go myself, depends what size ill get and how much room i have to work with. Plus You might want to hide those from some people, im sure cops know exactly what a turbo looks like so hide it, but if you dont care, show it off lol...

Get one mounted sideways!!! i havent seen that one yet lol...

[AWDSR20]

honestlly i don't know if a top mount cools the turbo better.... (don't want to give the wrong info)
i think nissanfanatic explaind it best...

[logik23]

I'm pretty sure you want colder air, that's what an intercooler is for, I thught they wrapped the manifold and turbo so the heat didn't screw up other shit.

[Hit_N_Run-player]

Originally Posted by GT500916

First question i want to know is, do you know what size turbo that is hes running there? the A/R on that or any info on that top mount turbo??

No, i was just posting that pic to show a reference of what i meant by top mounted so i wouldnt get a bunch of ppl confused on what i mean LOL...

[nissanfanatic]

Heat is energy. We all know that. Too much or too little can be a bad thing. You want the most heat from the engine to be run through the turbine housing. Exhaust pressure, heat, and noise energy all transfer from the turbine housing to the compresor. Heat is the enemy on the compressor side of the turbo. An intercooler is used to dissipate heat created by the compressor. Most of the heat is created from just compressing the air but some is just transferred over by the turbine housing. This is why sizing is important. An improperly sized turbo can create much more heat than a properly sized turbo because of its efficiency range. You want at least above 60% efficiency. You can be picky and choose higher percentage, but 60% is about as low as you would want. Don't use wrap. Get the manifold ceramic coated. Wrap will destroy the manifold very quickly. Niether position is greater than the other for cooling. An oil cooler or water injection would be the best way of cooling the turbo faster. Niether spools faster(unless you assume that hot air is lighter and will rise into the turbo but that is irrelevant). Sideways is pretty much impossible on a 240.