Lightyear's SE Replica Track/Road MX-5

[lightyear]

Mine should look more like the first one. I decided not to drill and tap the block by myself as I don't have the right size taps, and prefer a bit if help to make sure it all goes well. So going to Lux Racing next week. There are a few jobs he has to do anyway. Like weld the intercooler pipes, as well as the water outlet housing.
It's not easy getting the pipe work reducers. I have to go from 1.75" to 2.5" with 2 x 45* bends or elbows on the intake from the pod filter to the turbo.
Turbo outlet is 1.5" to 2.5" with a 45* bend, a straight and a 90* bend into the intercooler.

I should get the intercooler tomorrow hopefully. Ordered on the weekend. They say 2 days shipping.
I decide while it is half apart to replace the engine mounts with new Mazdaspeed ones I have had for ages. One was starting to fail by the look of it.

The new (and hopefully last) clutch ready to go in. I decided to leave it off till the block is drilled. One hole is about 5mm away from the gearbox. Would be hard to get the drill in with the box on.






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[lightyear]

Not a lot of progress. But the intercooler is in. And the pipe work is all there. I need to weld the 90* elbow on the 2.5" pipe, and put all the hose clamps on. I am not going to drill the block for water and oil. Just doing it the normal way the aftermarket turbo installs are done.
For the inlet, I had to buy a 45* 1.75" elbow and a straight 2" to 3" reducer, a small piece of 1.75" alloy pipe to join the silicon hoses together, and a 200mm length of 3" to go to the pod filter.
For the turbo outlet I reused the factory 1.5" 45* pipe cut and turned. Then 1.5"-2" reducer with a small piece of 2" alloy, 2"-2.5" 45* elbow. Then 2.5" alloy to intercooler and to TB.
Total cost was about $90.00 for the pipe work and reducers. Lucky I found 2 that worked in the $5 bargain box.
Intercooler was about $200.

very simple and straight forward :0


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[beavis]

I know nothing about anything, but you might need to replace the little air filter on the valve cover with a proper catch can.

[speed]

Suspect the shorter pipes will give better throttle response. Looks good too.

[lightyear]

I have a left over catch can. I plan on using it with a self draining design. Never needed emptying on my old turbo car. But will put it in just incase.
Don't think there is much difference in throttle response. But it can't hurt having shorter IC pipe lengths.

[Ned Loh]

I looked over the data from the weekend at Sandown. The speeds are way down from the red MX5 I had previously. Back straight is about 10km/h slower. Obviously there is more to getting hp than just doing the A/F ratios. Not going to tune it till the turbo is on.

who is going to tune it?

[lightyear]

Not sure yet. Might start with a road tune and see how it goes. I don't really want to spend the $850 for a tune from checkered.

Took the car down to Nick at Lux Racing. And it's pretty close now. It runs and drives with the turbo on. Water and oil lines are done, intercooler piping is done. It's all bolted up, exhaust is hooked up.
A few things need to be done, like the catch can. The biggest job will be the ducting of the radiator and intercooler. I think that will be a 2-3 night job.


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[lightyear]

I started with the main part of the duct I made previously. Changed the shape from a curved inlet, to an S shape to clear the intercooler. Trimmed the bumper opening reducer pieces so they sit inside a bit. Rather than stuck on the outside. The opening is 80mm wider than before.
It's all working well. Need to finish the top panel. And use some of that super sticky silver tape with the gummy backing to finish up any holes/gaps.






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[Okibi]

Nice work Dave, ducting any air to the brakes?

[lightyear]

I started looking at that last night. I need to modify the metal shield behind the brakes or make a new one like Goodwin racing sells.
I need new pads too.
I will use the light recesses in the bumper for the inlets.

[lightyear]

Ducting is finished for the intercooler and radiator. Working on the airbox.


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[lightyear]

So Brendan and I did the last few jobs needed to drive and tune it. Like the RX8 injectors, and block the EGR hole in the manifold.
We went out to start checking A/F ratios with a base tune he found. Was at 17.xx. Then his laptop battery died. So had lunch, downloaded it all on another laptop, and it started raining. We ended up getting the A/F ratios pretty good, then added the MBC as it was running 7psi. I want about 10psi. Rain got heavier as did traffic. So called it a day. There is no grip under 5th gear. So cool to have a car that starts, idles and drives like Oem with such little fuss. Will need to drive around and use up the fuel so I can fill up on E85 and get it dyno tuned so I know it's safe to track. We couldn't tune much above 5000rpm due to being on a public road.

[davekmoore]

So the ickle IHI is holding up then?

If you and Brendan can now do a Megasquirt do you reckon you could also do a Haltech including maybe showing a fool like me how to do it (assuming I ever get the oil leaks sorted)?

[lightyear]

This is only tuned to for air fuel ratios so it can be dríven. I will need it tuned properly by a professional before I put it on the track.

[lightyear]

We had another go at tunng it. But it has a very harsh cut in 4th usually at about 5200rpm. It did have one clean pull to 7000 going down a hill in 4th. Fark, it pulls hard. I can't believe that tiny little turbo can make the car go so well. If you don't have a turbo, your really missing out.
I just think why haven't I always had a turbo MX5. I started with one...
Anyways, here is a video showing the harsh cut out. It's a complete loss of power.

https://m.youtube.com/watch?v=mkoxNRSlOlc

It's a quick car now, can't wait to see how many seconds it will make on the track. And people that have man sized turbo MX5's, man, they must be insane to drive. This feels like enough for a fun car.