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Im running approx 650bhp with a T78 just now but i feel its too laggy and have to really give it some off the start line (best 1/4 has been a high 12! :eek: )

So i was just wondering what would i need to do to fit a To4z in its place?

thanks,

Andy.
 

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Totalburnout said:
Im running approx 650bhp with a T78 just now but i feel its too laggy and have to really give it some off the start line (best 1/4 has been a high 12! :eek: )

So i was just wondering what would i need to do to fit a To4z in its place?

thanks,

Andy.
Andy read your sig - Power is nothing without control! - Just practice your runs and you should see low 11's poss high 10's

What I started in my GTR the best time I got was 13.4 @ 107 MPH. My launches and gear changes were poor. Now I have run a 12.3 @ 112MPH after about 30 runs up the strip. Just needs practice mate - and I am only running 1bar @ 400(ish) BHP :)
 

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Discussion Starter #3
Cheers Dan for slagging my driving! :D

seriously mate i do need to get some more runs in, dont nearly get enough practice!
I might still be thinking of a change of turbo next summer though.....
 

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IIRC the T78 and T04Z use the same manifold 4 stud flange. I think that the T04Z turbine outlet is smaller in diameter then the T78 so a modified downpipe would be needed, maybe one of the gurus can confirm this.

:thumbsup:

As for slagging your driving, we have all been there and I am still a newbie at it. Just wanna get my car in the 11's now
 

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You'll need the manifold & downpipe welded with new flanges to fit, plus coolant pipes made up and then a remap - I've just changed my T78 to a GT3540 for circuit use :D

Cheers :)

Rog
 

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Hi Rog

I have a T78 at the mo how does the GT3540 compare?

When is it on full boost.

Cheers

Neil
 

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we run 10.08 on a to4z with no noz - FULL boost is still 5000 rpm though , but spools from a lot lower than that
 

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neilo said:
Hi Rog

I have a T78 at the mo how does the GT3540 compare?

When is it on full boost.

Cheers

Neil
I'll let you know once it's all completed - hopefully in a week or two...

Rog :smokin:
 

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The Admiral said:
I'll let you know once it's all completed - hopefully in a week or two...

Rog :smokin:

Yes I am very interested how you get on, I have 2540's at the mo and am finding them to laggy.

Totalburnout, It's not all about the driving mate, the car setup plays a very important part (the most important) I ran a 12.01 with 385bhp in my old GTR at 0.9 bar. I only managed a 13.03 with my current car running the laggy 2540's and 600+bhp! The car wouldn't launch :smokin:
 

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I am doing exactly the same conversion.

My T78 setup works pretty well from 4K but is a real pig for town driving so I'm making the switch. I have a leaky manifold as well so my choices are a little different from making what I have fit.
I have ordered the HKS kit 1103-RN027 but with the T04Z so it should have everything I need.
Kit lands next week so fingers crossed.
 

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Here's my old T78 setup (unknown cams) on 1.2bar:





It pulled 624bhp on 1.4bar, but I don't have the graphs...

Am now running GT3540, PowerFC, bigger injectors, different AFMs and intake, so will be interesting to compare...

Cheers :)

Rog
 

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Barrie said:
we run 10.08 on a to4z with no noz - FULL boost is still 5000 rpm though , but spools from a lot lower than that
pmsl thats horrendous! I have full boost about 3500-4000rpm on my bridge ported 13b running a TO4Z! my god that RB is a lag machine, the main reason I no longer own one ;)
 

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Not far off - the baseline is 120lbft, though :p

I must confess I am a HUGE fan of the old school turbo "launch" effect - makes my m8s 500bhp M5 seem VERY sedate, but given that I need to change my turbo anyway, I thought I'd fit something a bit smaller and more modern for better road and track drivability :D

Can't fault the T78/T88s ability to produce top end power though...

Cheers :)

Rog
 

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Rog

My T78 on a Hks 2.8 whats yours?

This is using pump fuel.


This is using 109 race fuel



This was run in rear wheel drive on abbeys dynopack.
 

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Nice outputs :clap: What boost were you running in the various graphs btw?

Mine's std 2.6 :chairshot

Rog
 

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1.7, 1.2 and the boost controler off which i think is 0.5.

Neil
 

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I have been very pleased with performance of the T78 but when i get round to changing it I quite like some of the Garrett singles, which the price seem quite reasonable too.

I would need one that can give 800 bhp but would it spin up faster than my setup now??

Will be interesting to see the difference in your graphs.

Cheers

Neil
 

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AJFleming said:
pmsl thats horrendous! I have full boost about 3500-4000rpm on my bridge ported 13b running a TO4Z! my god that RB is a lag machine, the main reason I no longer own one ;)
Dont get me wrong the car spools a lot earlier and but hits 2.0 bar full on at around 4800 rpm its ok when they rev to 9.5 rpm:)
 
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