What's The Ultimate Turbo For My Needs?

[EXIT]

Hi Guys,

Well my project is coming together at last. I will post a full update later but I've been wrestling with the turbo question for a while so I thought I would throw it out there and maybe some guys who have been there and done that can share their experience?

My fully forged engine is almost complete and I am going to be doing the big transplant before Xmas. I have decided to go external wastegate and have bought a manifold to suit. I have been trying to decided whether to use my existing turbo and block off the w/gate or sell it with the motor and gearbox as a complete setup.

There are financial decisions there but putting those aside my question is this-

What is the absolute very best possible turbo I could use for my circumstances?- which are:

It's my daily driver and I do a fair amount of around town.

I want lots of power as smooth & responsive as possible.

I'm thinking 400+ rwkw

I'm the kind of guy for whom enough is never enough for long so I need some blue sky potential ( even if I find I never use it)

6 speed manual, Process West plenum/ cooler kit, stock cams, maybe an EBC too.

Thanks.

[INFLYT]

The standard Turbocharger, once modified, would do the job nicely to suit your requirement's.

[RAP1D]

Seeing as your happy to use an external gate ( very smart move ) I'd look at some around the 700 to 800hp rating... T04z would be my choice and with clever tuning it should be very streetable and give you 400wkws with around a bar of boost... tuning is the key with this sized unit though, an ordinary tune will make it a dog to drive in low rpm.

GT35/40 ext gate is another option to yeild better low down punch

[DAWSEY]

NOTHING BUT A TO4Z......

[EXIT]

  RAP1D said:

Seeing as your happy to use an external gate ( very smart move ) I'd look at some around the 700 to 800hp rating... T04z would be my choice and with clever tuning it should be very streetable and give you 400wkws with around a bar of boost... tuning is the key with this sized unit though, an ordinary tune will make it a dog to drive in low rpm.

GT35/40 ext gate is another option to yeild better low down punch

I'm very interested in the TO4Z option.

Brad from Spool Imports, who has supplied my rods and helped me a lot with this project, has a TO4Z on his 3 litre/ RB26 head skyline. It makes totally spastic horsepower and I have driven it and it feels no laggier than my stock T. Now I realise this is a poor comparison in many ways but there is some logic to my thinking-

His makes 15psi @4000rpm and 20psi by 4500rpm with a 3 litre ( see graph below)

A 4L engine will produce approx the same volume of exhaust gasses @ 3000rpm as a 3L makes @ 4000rpm so I figure a TO4Z should make around 1 bar @ 3000rpm- even if that turned out more like 3500rpm in practice-I could live with that and be very happy.

Anyone have a dyno graph of a T motor with a TO4Z on it to see how this pans out in the real world?

[RAP1D]

Yeah, there's no reason why a 4lt motor with good flowing manifolds ( as you have ) cant spool a turbo of this size with little lag.

I know of a T04z on a SOHC 4lt in an ED that spools well.... I'll see if I can get a dyno print out from it

[senna_T]

T88h-34GK the mother of all turbos! unlimited power, lots o lag but when it comes on - WOW

[spoolup]

I think the Idea was limited lag :-)

A Garret ball bearing T04Z with 0.96 A/R single entry exhaust housing is the go.

[senna_T]

being serious, I think the TO4Z is the go, 3037's are really quick to spool, but it wouldn't be big enough for the 4.0L

[EXIT]

So can anybody post a dyno sheet using a TO4Z?