August 18, 2016 12:00 am - Published by

Now I mentioned before the Megasquirt and a bit more power- so what happened with that?

Well, throughout this season on a stock 1.6, I actually started to have a LOAD of fun with it being underpowered. It was frustrating at times, but I’m naturally a nervous driver, and I think having the extra power on tap would make me lackadaisical and pick up bad habits, so it’s staying N/A to force me to grow a pair and throw the car in harder. I think I’ll be a better driver for it in the long run!

Anyway the story:

While still at work, I picked up a set of GSXR 750 throttle bodies with a cut 1.6 manifold for £120 from a fellow Nutzer.
They came with a set of short hoses, fuel rail but no TPS.

I decided not to use the GSXR fuel rail, even though I would likely get better mixing from doing so, the extra complications of converting the system didn’t seem worth it, and I stuck with the stock fuel rail for the MX5.


I managed to pick up a compatible TPS from one of the old cars and convert it to fit the throttle bodies with a lovely machined adaptor block.


The throttle (just) works with the stock cable, though the throw is reduced to about 3/4 of the original travel, which should make for a responsive and interesting drive!
Here’s the setup built up with some test filters. The original secondary throttles are blanked off with freeze plugs, and the original injector bores were converted to vacuum takeoffs (as it turns out, completely unneccessarily…



Then, a solid week of fitting just last week saw the ITB setup get ready to run!
… but sadly with the original straight hoses, the filters just did not fit. See video: https://www.instagra…raxledivergence

No bother, I wanted to get some 45 degree hoses anyway. A quick £50 order saw 4 little elbows arrive. New fitting brackets to hold the throttles were made up and fitted to the car.


And… against all odds… IT RAN! (like a bag of shit)

Categorised in:

Leave a Reply