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Hi all,

I've got a 25 with top mount manifold running a t3/t4 which is supposed to be a 450hp turbo.

Now my questions are as follows...

If a turbo is rated at 450hp at 20psi what power in kw will it make at the wheels ?

Which is the best turbo for a 25 as an upgrade out of gt30,gt35,gt3540 or gt3040.

I dont want exessive lag so i was going for a .82 exhaust housing so i basically want to know which will go about making 300rwkw with the most bottom end to midrange on the least boost.(ideally 18psi)

Thanks for any help.

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If a turbo is rated at 450hp at 20psi what power in kw will it make at the wheels ?

450bhp / 1.34 = 335kw

less ~60 kw for losses = 275 rwkw.

An example, we have an R34GTT with a GCG ball bearing hi flow and it makes 265 rwkw.

Hope that helps :uh-huh:

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What about this turbo pushing 7psi on some crazy 6ltr stroker ? stupid I know but the car will make more then 450HP !!

Its silly to assume the turbo on any given boost is going to produce ex amount of power on your car. The turbo being rated at 450HP means it can flow 450HP but before this turbo goes on your car you might already be making more then 450HP...

As for 270rwkw at 20psi with that turbo you might not even get that !

Get your max fuel/ignition to boost levels you/your tuner want. See what power you make then that’s a clearer indication of what turbo you should go to.

IE: 14psi might be more efficient then 20psi on your car's setup. No one can answer that but the tuner on the day.

BR,

JH

1.3 bar
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What about this turbo pushing 7psi on some crazy 6ltr stroker ? stupid I know but the car will make more then 450HP !!

Ah no, the turbo only flows enough air for 450 bhp (about 45 lbs per minute). So if you put it on a 600 bhp (without turbo) engine, it will loose power. ;)

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Ah no, the turbo only flows enough air for 450 bhp (about 45 lbs per minute).  So if you put it on a 600 bhp (without turbo) engine, it will loose power. :rolleyes:

That wasnt what I said I said the 600Bhp motor would still make more then 450HP thats what I said. I know the restriction in its exhaust (the little turbo) will cause it to lose power.

Read more carefully.

BR,

JH

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That wasnt what I said I said the 600Bhp motor would still make more then 450HP thats what I said. I know the restriction in its exhaust (the little turbo) will cause it to lose power.

Read more carefully.

BR,

JH

Still no!. The turbo flows 45 lbs of air max, so the engine makes ~ 450 bhp, not 500 bhp or 550 bhp. :cooldance

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Would anyone else like to answer my q?

WHAT ****KING TURBO SHOULD I BUY TO MAKE 300 RWKW WITH THE MOST BOTTOM END TO MIDRANGE AND ON THE LEAST BOOST?

Are they all that similar with the .82 back?

Cheers :rolleyes:  :rant:

What other mods are you doing for the 300 rwkw? The turbo is best chosen with all the facts known. :cooldance

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Still no!.  The turbo flows 45 lbs of air max, so the engine makes ~ 450 bhp, not 500 bhp or 550 bhp. :cooldance

Honest to god if you believe that Im going to prove it wrong to you in person, just give me 3 weeks till this 6ltr stroker is finished and ill show you it peel over 450HP with a 450HP turbo on it. You can watch it get dynoed.

:headspin: :headspin:

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Honest to god if you believe that Im going to prove it wrong to you in person, just give me 3 weeks till this 6ltr stroker is finished and ill show you it peel over 450HP with a 450HP turbo on it. You can watch it get dynoed.

:headspin:  :headspin:

If it flows more than 45 lbs of air per minute, then it isn't a 450 bhp turbo. :)

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Oh its 450HP.... It runs 2 of them Im going to leave 1 off and dyno it  watch it crack over 500HP  :headspin: (Boat motor)

BR,

JH

Well, well, whadyaknow, here was me thinking this guy is crazy. You are going to have some strange tuning issues to overcome though. :)

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