The Mite
Part :47

Plumbing Turbo Oil lines, Heater hoses, and Fuel System


Turbo Here's the IHI-RHB5 turbo. The hole in the center section is the oil drain hole, the stock oil drain is shown on the far right. I want to use braided stainless for the drain, so I'll have to weld the -8 an fitting onto the flange
Drain fitting The -8 fitting has been brazed onto the stock IHI flange and now will accept a -8 hose end.
IHI RHB5 turbo oil driain fitting Here's the finished and painted fitting on the turbo
RHB5 turbo on miata engine And here's the turbo on the car and you can see the oil drain hose coming out of the bottom of the turbo and going to the fitting that I welded onto the oil pan previously
Turbo drain fitting Here you can see the oil drain hole, as well as the proximity of the steering shaft to the turbo
Custom Mite miata heater hose I also needed to plumb the heater, and thanks to a Checker auto supply that actually has the heater and radiator hoses on display, I was able to find some hoses that match up exactly to the location I needed!
Custom Sprite Miata heater hose Once the hoses were found and attached, I replaced the cover on the heater and re attached the electromotive tec-2
Custom water lines IHI RHB5 turbo miata engine I also needed to run water lines to the turbo center section. There were some convenient fittings in the Miata's water neck and return that made the plumbing relatively easy. i drilled and tapped the water neck and water return for 1/4 inch pipe and threaded in pipe-to-dash 8 fittings. I cut apart the stock turbo water inlet pipes, cleaned and painted them and re-attached them in the locations I needed to clear the turbo and the steering shaft. I also ran a teflon-lined -4 hose from the oil feed fitting in the block to the turbo
Miata engine Sprite Here's the front of the engine
Miata in a Sprite And the side, showing the manifold and the oil and water plumbing. That oil line will be clamped down soon
Fuel Rail, Supra Injectors Regulator

Next is the fuel plumbing. I got a set of 6 used injectors from a Toyota Supra Turbo.

They are 440 cc/min and low-impedance. I sent them off to RC Engineering and had them cleaned and flowed. They are all just like brand new and flow within a few percent of each other. Also shown is the modified fuel rail and the Aeromotive boost-referenced adjustable fuel pressure regulator. It will keep the fuel pressure at 43 psi regardless of the boost.

Custom Fuel rail in place Here's the rail and injectors installed
injector sheet This is the pre- and post-cleaning sheet from RC Engineering. It shows the cc per minute flow for each of the injectors before and after cleaning.
Aeromotive Fuel pressure regulator The fuel pressure regulator has a nipple fitting for the vacuum/pressure line from the manifold, but I want to use some -4 braided hose, so I'll have to drill and tap the regulator for a pipe thread
Modify Aeromotive fuel pressure regulator I took the top of the regulator and drilled out the threaded hole
modivy aeromotive fuel pressure regulator Then tapped it 1/8 pipe
Aeromotive regulator on Sprite And screwed in a 1/8 pipe to -4 fitting and ran a braided line to the manifold to allow the regulator to sense boost, the fuel lines from the fuel rail have also been run to the regulator
Hard fuel line I made hard lines to bring the fuel from the pump to the rail and return from the regulator. I bent the lines where needed, then slipped the nut and collar around the tube and then flared the tube with a 37 degree flare tool to allow it to seal to a - fitting
Hard fuel line to dash 6 braided Here's the feed and return lines poking up into the engine compartment
Regulator installed And here's the regulator in place
Radiator And soon, the radiator needs to be plumbed!
Fuel pump and filter This is the Walbro fuel pump and the fuel filter. I connected them with a bit of -6 line to provide some resistance to vibration
Filter and pump mounts I discarded the old fuel pump mount I made and fabbed up a new set for the pump and filter
Fuel pump and filter and braided line on Austin Healey Sprite Here's the pump and filter zip-tied to the mounts with all the hoses hooked up. I wrapped a bit of radiator hose around the pump and the filter to help with vibration and noise, and on final assembly, they will be hose clamped to the mounts
Back view of sprite Here's what traffic will see....
2332 VW engine for sale And finally, here's a 250 hp, intercooled blow-through turbocharged vw engine That was on a buddy's sandcar. . It's 2275cc and the only VW part on the entire engine is the dipstick. Click the Picture for larger image and build sheet.


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