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DYNO RESULT:

This is the email Beno sent me when the car was ready for pickup. I will let someone who knows about GTRs summarise what the RB28 V Cam feels like on the road:

Ben writes:

Hi Matt,

Car is final tuned now and the result is quite awesome.

Best road R34 GTR I have driven.

It makes 412kw @1.5bar.

Super smooth and mega responsive on the road.

Sounds great - cruises quiet as a mouse,

but step on the gas and it howls like the Mines R34GTR !

You are going to love this thing.

cheers,

Ben

The all important dyno graphs:

RB26 NUR vs RB28

dscf0092r.jpg

RB28 Power vs Boost:

dscf0094h.jpg

RB28 Power vs Lambda:

dscf0095x.jpg

Will post pictures of car this afternoon. Need to clean car first!

Awome build mate is a credit to yourself and race pace. Is always good to see cars built to such a high quality satndard

(parts and workmanship included). Would no doubt be one of the best road cars doing the rounds. As richard (beerbaron) said I cant fault the combo you have gone for. I can only wish the budget would allow for a v cam set up for my own car as an RB28 with Vcam and set of HKS 25/30 or GTRS would be the ultimate combo in my personal opinion.

Great result Matt. Thanks for the comparison of the RB26-RB28 too. You can see where the added displacement and vcam fix the dip in the power delivery as it climbs onto boost.

Do you have a sheet with the torque figures?

Thanks for compliments everyone!

9krpm Posted Today, 07:40 PM

What else has been done to the head beside the vcam mate?

I am led to believe that the head has received no modifications, no porting and polishing. But there could have been some 'secret sneaky tricks' done that Racepace did not divulge.

GTRNUR Posted Today, 08:12 PM

Do you have a sheet with the torque figures?

Sorry, I don't have a sheet for torque figures.

Isn't the torque curve on this graph?

dscf0092r.jpg

It's interesting where the power and torque curve intersect.

Very typical of a variable valve; it's similar to my turbo honda s2k dyno.

It would be nice to have rpm on the x-axis but I am just being picky :D

It's great to have a tuner/workshop that is dedicated to his work and customer service by sending you all of these information after his work.

Unlike a place that I've been to, I had to chase it up for weeks and still failed to get a final dyno run.

Needless to say I and my friends won't be back there in a hurry :banana:

:P for racepace ;)

Edited by 9krpm

wow... that's a power curve to make anyone jealous! can't imagine how good it feels on the road... power and boost curves are really linear, makes it far easier to drive fast

it looks the goods as well... those Z Tune guards are sooo nice

Could anyone enlighten me on how to interpret the power vs lambda graph. What is considered a safe tune?

Cheers

Matt

Matt,

To get the air fuel ratio you just multiply the lambda by the Stoich ratio (14:7) for petrol. In your tune the Lambda is showing about 0.82 which is about 12:1, which is spot on. My engine runs the same number and has had the living bjesus belted out of it for nearly 2 years.

Regards

Andrew

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