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Customer Testimonials

John - September 2015

Hi David,

Hard to believe that the car is the same one that I gave you, it is such a major transformation in driving pleasure, whereas the car previously appeared frustrated and so was I as the driver, it now it feels "right".

I'm looking for an excuse to take it for a decent run as that is where it should truly show the changes.

So thanks to Chris and your team for a great job.



Pauline - March 2015

Hi David, James & the team

Just wanted to tell you how rapt I am with the results of my tune & addition of the cold air intake filter. The extra responsiveness was evident straight away even around town but I took the car to Tekapo in the weekend and gave it a good run and it was brillant. Even with some intermittent bursts of serious jandel it did the round trip of 495kms on an average of 10.06litres per 100kms - you can't compain about that in a V8!

Money well spent and thank you very much! 

Kind regards,



Lex & Vi Cummings - September 2014

We took our 2007 SS Commodore to Harman Motors Ltd to get a sporty exhaust.

But it was like being a kid in a lolly factory. David and the team replaced our cam and pacemaker headers were fitted. Cold air induction kit was added, then James Custom Tuned it.

We were blown away. It is something you have to feel, you have no idea of the torque and sound that this beast now has. We have never had a vehicle that we treasure so much. If it's a mid life crisis, then I wish it had come 20 years ago.

We cannot recommend these guys enough. A dream come true.

Lex & Vi Cummings
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Graham Pulford - July 2013

I bought my VZ SS Holden Commodore 3½ years ago and my friends talked to me about the advantages of Custom Tuning. After some time thinking about it and a few earthquakes later, I decided to call into Harman Motors and see what they suggested.

After I explained my interest in making my car more efficient, David showed me a number of options and I decided to get a 2½” cat back exhaust, OTR cold air intake and a MAFless Custom Tune.

When I picked it up I could tell it was clearly a different car by the time I had driven 300 metres along Colombo Street. Way better pulling power from low revs, smoother running engine and gear changes.

James did a great job tuning it on the dyno. Now I am hardly touching the accelerator pedal around town, but when I do, it feels like a race car! It now produces an extra 32kw at the rear wheels which is an extra 40kw at the flywheel. The exhaust has a nice V8 sound now, but not noisy. Exactly what I had hoped for.

On top of all that it is much more economical. I am rapt.

Graham Pulford
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Wayne - February 2013

Could you please pass on to the boys that we are very happy with the exhaust system on our XR8, it sounds awesome and with the K & N air filter and computer tune, it's definitely more responsive and pulls harder. Thanks again.


Hamish Templeton - September 2012

A note of appreciation ............ Neil Stuart Auto recommended Harman Motors to "performance tune" my Monaro CV8 which you completed recently.
I cannot believe the improvement and I am absolutely rapt with the result - you guys are magicians.
I have the Dyno sheet which indicates 222.2kW at the wheels now.
Thats a huge power increase & the car definitely performs now as I wanted it to.
More economical too - thank you for the good work.

Hamish Templeton
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Graeme Sargent

On the 20th February 2011 I dropped my Holden GTS 325 series 2 at Harman Motors to have a custom tune and mild cam fitted. Two days later the devastating earthquake struck and after watching all the media reports in that  area and seeing on the news the church next door had come down I naturally thought it would be the last I saw of my new GTS.

Knowing the staff at Harman's would have their own personal issues to deal with I left it a couple of weeks before getting in contact with them. To my surprise David was very sure all was OK with the car when he had left the building and we just had to wait until they got the all clear to go back into the area.

A month later I picked the car up without a single scratch on it and partial work done on the car.   The dyno work was not possible at that stage due to earthquake damage. Several weeks later I returned the car and everything was completed, and I am very pleased with the performance.

All credit to the staff for getting their workshop up and running in what must have been very difficult times for them.

Graeme Sargent

Andy Clayton

I wanted my Crewman Cross 8 to perform like a V8 should and now it does!

I went to Harman Motors and followed their recommendations. Improved exhaust, cold air intake and their custom tune.

An extra 30Kw, quiet on the open road, then sounds and feels great when I accelerate. It is fantastic, all I wanted and more.

I even went to the drags at Lawrence and had so much fun!

Most of the Holdens there that were doing well had been to Harmans too. I never thought I would do any of this, but now I want to see what else they can do.

Andy Clayton


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Christine Horne

My husband had his SS Ute modified at Harman Motors with stunning results, so when I bought my new VE SS V we decided to give it the "Harman Motors treatment" as soon as possible.   At 5,000k they fitted free-flows, new rear mufflers, cold air intake and then Custom Tuned it. What a difference - smoother, much more responsive, better fuel economy and a great sound.   85,000k later, no engine trouble and one very happy lady.

Thanks for the great service.

Christine Horne

Paul Pasco

I had owned my VY Crewman since new, but it always felt a bit dead compared with my VU Ute, partly due to being a heavier vehicle. I had headers and a different cold air intake fitted which did help a little.

I came up from Bluff to the Rangiora Muscle Car Show where I met John and David Harman at lunch time Saturday. They explained that a Custom Tune would get the best out of my Holden, so it was done by late that night. An extra 24 KW at the rear wheels!

On the trip home on Sunday, it clearly had more power and better fuel economy. On the open road I can now do most things in 6th gear, and very comfortably.

I wouldn't have thought it was possible!

Thanks boys for the great service. I wish I had known about you earlier.

Paul Pasco (Bluff)
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Andrew Good

I have been in the automotive industry for the last 20 years and spent the first sixteen years employed by a large Holden dealership where I began my career as an apprentice. I worked my way through to service foreman before leaving to establish my own business, GT Performance Ltd, specialising in repairing and servicing Holdens and HSVs. I gained a vast experience working on new and near new Holden products including being factory trained by HSV. Amongst other achievements and experiences in 2002 was awarded with being the Top Holden Passenger Technician in New Zealand.

I have been involved with local motor sport and have carried out modifications to the Holden product over the years and in recent times to improve performance, from intake and exhaust modifications and engine management upgrades to camshaft changes etc.

Having recently been introduced to the more modern side of engine management enhancements through Harman MotorsCustom Tuning”, I have experienced first hand with my own V8 Ute the incredible transformation in drivability.

The team at Harman Motors has not only made significant power and torque gains, they have also enhanced throttle response, transmission shift and even fuel economy, on a vehicle that is otherwise standard.

I would without doubt recommend this service to anyone looking at upgrading their vehicles performance as it quite honestly has “exceeded my expectations” something we all strive for.

Andrew Good
GT Performance Ltd
Holden & HSV Service Specialist
03 349 4130
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Gavin Blackwood

I have a VE Holden SSV 6.0 auto with headers and big bore exhaust and I had it Custom Tuned at Harman Motors in Christchurch.

It gained an amazing 24 kilowatts and fuel efficiency improved from 11 to 10.5 litres/100km. Acceleration was much stronger, especially noticeable at lower revs.

Then recently they fitted a cam, cold air intake and tuned it MAFless. It gained an extra 54kW again! The power increase is huge. Under full acceleration the front of the car lifts up and just stays there, pulling hard all the way. I love it!

Fuel economy is still good and I have gained nearly 80kW at the rear wheels.

1/4 miles are so much fun. After the Custom Tune my VE holden SSV with headers and big bore exhaust and cold air box intake could do it in 14.4 seconds, now it is 12.7. I am thrilled with the results.

Gavin Blackwood
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