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Discussion Starter #1
well alot know about the altima and how im selling the z and wont be around anymore....but me and the old man are trying to find a project car, and with hybrids super sweet ride...i may have to find a n/a and do a swap... ill show you the face of the car i have to see driving home everyday (which is what got this whole project 300 ball rolling in my head)

SO THE QUESTION IS: what would i need for the swap??? tell me if im wrong... the ECU, the manifolds, the turbo (drrr), the wiring harness, the injectors,ummmm, the downpipe, the intake, the recirc...is that it?? fellow swappers..the help is greatly appreciated..

thanks guys
 

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If you haven't bought the car yet you should just buy a turbo. The only reason that anyone does the swap instead of buying another car and selling their current car is because they are attached to it.

I would buy a turbo z31 and make that your project car. It will already have all of the basic structure, you can spend your time upgrading the turbo, etc, and you can be cranking some serious HP in no time.
 

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<http://www.redz31.com/pages/turbo.html>



Post Edited (Sep 20, 10:58am)
 

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naw, i'd rather change parts on my n/a than buy a turbo. i'd rather keep the 9.0 compression ratio rather than go down to 7.8. see, putting compressed air into the cylinders via a turbo charger effectively raises the compression ratio inside the cylinder. in terms of physical volume, obviously this cannot be changed. but in terms of mass of air, you're putting a lot more air thats already been compressed to a large degree, and then compressing it 9 times more. this would result in much more power than using the turbo engines 7.8 compression ratio.
 

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what year altima? i used to have a '97 Altima SE which had the same 2.5L engine that the new Sentra SER and Altima 2.5S use, although in '97 it only had 155hp in stock form. i always wanted to put a turbo on that car, it seemed even faster than my 300zx, which it may have actually been since its a smaller lighter car with comparable horsepower.
 

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nope, you're right. i just looked it up. 1997 Altima Limited Edition comes with a DOHC 2.4 litre, 150hp. i must have been thinking of something else. either way, that car would go.. but i hated the auto tranny and i hate front wheel drive. my second car was a '92 Jeep Cherokee that i lifted 4" with a new suspension, then i sold it and went a year with a longboard as my only form of transportation.
then last summer in june i bought myself my favorite car since i was a very young kid, the z31, as a little birthday present to myself for my 21 birthday. i love my car, cant see myself owning something else at the moment.
 

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phxZ31 said:

"i'd rather keep the 9.0 compression ratio rather than go down to 7.8. see, putting compressed air into the cylinders via a turbo charger effectively raises the compression ratio inside the cylinder. in terms of physical volume, obviously this cannot be changed. but in terms of mass of air, you're putting a lot more air thats already been compressed to a large degree, and then compressing it 9 times more. this would result in much more power than using the turbo engines 7.8 compression ratio."

i've heard that this is much harder on the engine, which makes it controversial. if you're going to beat the poop out of the car, then by all means go with the N/A compression. personally, i was wary of what i heard about running turbos on 9.0



Post Edited (Sep 20, 11:55am)
 

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it isn't that much harder on the engine unless you're running crazy high pressures with the turbo. running 10psi or less shouldn't cause too much abuse to the engine. the main reason they lower the compression ratio on turbo cars is this:

turbo's create lots of heat, not only because they use hot exhaust gas to drive the compressor, but also because the compression itself inherently causes more heat. this, along with the higher effective compression ratio caused by the compression in the cylinder of already compressed air, is a lot more likely to produce knocking or require you to use premium grade fuel with higher octane rating.

sure if you're trying to put 20-30psi of boost through the engine it puts a huge amount of stress on your pistons and crank because it takes a lot more force to compress each chamber and turn the crank.

can somebody confirm this:
somewhere i read that the 84 - 86 turbo z's used the 7.8 compression with about 7-8psi of boost, but the 87 - 89 turbos used the 9.0 compression with 4 -5psi of boost. the power output of both setups would be about the same, so it makes some sense, but for some reason doesn't seem likely that nissan would change things around like that.
 

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Discussion Starter #15
id rather ask red...so what is a safe boost pressure on the stock block of an n/a if i were to do a turbo swap on a z??

once again iknow its somewhere...just refreshing everyones knowledge :) thank me later
 

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"no one will confirm that, as it is not correct information. the W series engine - that is - 9/87+ used 8.3:1 dished pistons."

i was pretty sure that information wasn't accurate, but i wonder where i saw that before...
 

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84-86 was 6.7 psi
87-89 was 4.5 psi

IIRC



Post Edited (Sep 20, 2:23pm)
 

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17_6 :

i would start at stock boost to be safe, and slowly adjust it, listening for knock with every increment you raise it. above 10psi, an intercooler is strongly reccomended. once and if you hit 15psi, you shouldn't press it any farther than that. at that point you will be making dangerous amounts of heat even with an intercooler and the turbo will not handle the boost.



Post Edited (Sep 20, 2:21pm)
 

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god fucking damnit. would you **** asses stop posting wrong information?

how many times a week do we have to go over this?

84-87 Z31 Turbo: VG30ET, CR 7.8:1, T3, 6.7psi, 200hp @ 5200, 227ft-lbs @ 3600
88-89 Z31 Turbo: VG30ET, CR 8.3:1, T25, 4.5psi, 205hp @ 5200, 227ft-lbs @ 3600

And to answer the "how much boost" question....

Eleventy billion. Seriously. Depends on (but not limited to):
engine condition - includes:
pistons
rods
valves
spark plugs
wires
fuel injectors
fuel pressure
fuel pump
etc
octane fuel used
air density
temperature (air and engine)



Post Edited (Sep 20, 3:56pm)
 

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zbum... I can understand your frustration. Modifications need to be done for the right reasons and the right parts using the correct info or you wind up with a pile of stinky crap. Relax.. take a deep breathe. Breathe into a bag if you have to. Let them try and get 15 psi out of their turbos, with stock heads, run their cars on strictly acetone with a 5" straight exhaust . When things go boom and they start asking why then you can say " Ya idiot I told you eleventy billion times to read the posts." :)
 
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