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Rear diffuser on MK Indy
Mash - 11/1/17 at 11:13 AM

Hi Folks, happy new year all

As per the title, I want to fit fit one, to reduce the parachute effect, but I have a problem.

The chassis has two tubes either side which come out from the bottom of the chassis in front of the rear wheels, and straight, then bending upwards to meet the rail around the bottom of the rear tub. This means that if I did fit a diffuser, it would not be able to follow the edge of the rear tub, and there would be a long triangular gap each side, with the diffuser hanging down from the rear of the tub by about 100 mm

Will that still have a reasonable effect on the parachute effect?


nick205 - 11/1/17 at 12:00 PM

Having built an Indy and being familiar with what you describe can you not run the diffuser inside the chassis rails in question?

Doing it that way would allow you to fit it without the gap you mention.

Matt21 - 11/1/17 at 12:14 PM

Here is mine,

There is a trianle gap down each side, I have used 5mm spacers at the rear fixing points but they aren't essential. Under the car, it fastens flat to those chassis rails you mention, then slope up to the rear.

Mash - 11/1/17 at 01:40 PM

Thanks chaps

Nick, it would be a tricky job fitting it around the rails, but I suspect I could do something similar to what Matt has done.

Did you make it yourself Matt ?

zx12r dug - 11/1/17 at 09:41 PM


Got mine through mk but it's basically a gbs diffuser.A little bit of a fiddle to fit just a few brackets and rivets on the chassis and a couple of nuts and bolts on the corners

Toprivetguns - 12/1/17 at 06:35 AM

After the GBS diffuser also. Perhaps we could get a discount if we place a group order?

[Edited on 12/1/17 by Toprivetguns]

Matt21 - 12/1/17 at 08:05 AM

Yes made it myself.

I was looking into getting some laser cut for me to sell but kinda didn't get very far... I may see about making some though