INTERVIEW: KERN Racing 8.3 V10 Z4

Engine swaps have been getting a bit of a bad rep recently; it seems as though people are bored of LS swapped S13s & S14s. Saying that, we still love a well executed swap, and there’s something fun about shoehorning a gigantic lump into a small, lightweight car.

KERN Racing have taken this to extreme, by squeezing a Viper SRT-10 8.3 V10 into the rarely modified Z4 Coupe. We caught up with Eike from KERN Automotive to find out more about the build!

Hey Eike, we love the car. What inspired you to choose a Z4 chassis for the build? Are they readily available in Germany?

I always very much liked the Z4 Coupe. Also it is the last real Coupe made by BMW. The Z4 was sold by a VLN race team nearby. It was a complete car with small damage, and I have a lot of BMW parts lying around here.

Is the car finished, or do you have future plans?

The car is not finished yet. Even if it was running very well at the Essen Motorshow, a lot of things have to be done or must be improved.

Wiring with a new data logging system, improved steering and clutch hydraulics, several gauges and many other things have to be done until the car can get street legal in Germany. This should be done by the end of March.

Did you have to make major modifications to get the large Viper lump to fit?

Yes, quite a lot. The oil pan was cut 9 cm in the height and enlarged from 6 to 8 liters.

The exhaust manifolds had to be made completely new to fit the small engine compartment and to let the steering column go through.

To fit the length of engine and gearbox, we hat to cut and replace large areas of firewall and transmission tunnel. To get the chassis strong enough, Stahlus has developed a special roll cage with integrated transmission tunnel.

With this and the strengthening for the engine mountings the chassis got extremely warp resistant. Also the wiper and heater had to be replaced.

How does the car feel on track with such a heavy lump in the front?

It feels much better than I expected, because there is no heavy lump in front! The engine is completely behind the front axxle, so that the balance is still near to 50%.

We will check the wheel load in February and do some changes if required to get it as near to the 50% as possible, so that it will be really fast on track too.

It seems you’re happy with the end result; what would you change if anything?

I am very happy with the result and have not found anything that needs to be changed.

Great that you’re happy with the end result – what is your favourite part/element of the vehicle?

My favourite is the power and the sound of the engine. Especially when the valves in the exhaust are open, the V10 sounds gorgeous.

Have you thought about what your next project will be?

I have not thought about it. First we have to finish this one and some customer orders. Maybe we could start again by end of next year, but it will be difficult to find something more interesting than this.