9krpmrx8

iTrader: (46)

That's whats up.

TeamRX8

iTrader: (25)

It might kick the DSC in though

nlsolja123

I wish Some would venture with the Ecoboost. I have one sitting outside that is stock turbo with all external upgrades 93* octane, Last dyno I was making 419 rwhp at 24-25 psi.
the car just got hit and totaled while I was parked curbside outside my house. I doubt it would be cheap to buy the car from the insurance.
but seeing these seals makes me want to keep it just to install rubbing gear in my 8.

the main reason, 400 hp in a 8 would be enough. And my Eco mustang got 29-32 mpg and it's heavier than the 8.

John V

iTrader: (1)

Ecoboost is a lot more work for no real benefit. The 2.5 makes an easy 400+hp on much lower boost (14lbs). The weird cylinder head on the Ecoboost is going to make life difficult fitting into an RX-8.

John V

iTrader: (1)

Updated engine bay picture with the crankcase ventilation plumbing cleaned up, ECU relocated, and a few minor tweaks. Oh and the engine not canted over anymore. This was necessary to accomodate the GForce GSR 4-speed swap.

Now I just need somewhere to drive it

TeamRX8

iTrader: (25)

looks great, seemed more relevant to bump the SM thread though. Kind of dead over there.

maybe you should pull that soon to be rat-nest insulation off the LH fender well though or is it on there for some reason since the middle and other side are gone?

Is there not any way to fit a strut tower bar on there or is the engine really that close to the hood?

John V

iTrader: (1)

Eh, this whole site is pretty dead. This swap never got much interest so I lost interest in updating the posts.

Technically the insulation can't be removed in whole, only as needed to enable allowed modifications. Personally I think it's a pretty dumb rule, given the insulation there weighs next to nothing, but someone gave me a little grief about it when it was all missing so I put back in the stuff that still fit.

I have a stock shock tower bar that I modified to clear the engine but I don't run it since it just gets in the way and I don't see it serving much purpose.

TeamRX8

iTrader: (25)

my bad, thought that insulation could come out in SM. I knew the trunk trim had to stay, another dumb rule at that prep level. Kind of surprised anyone gave you grief over it considering a few RX8s in DSP have (or had) it pulled. I put all new engine bay insulation pads in mine just so it’d look nicer and it literally fell apart again already before I ever even drove the car . I’m thinking of wrapping them in gold foil or something less flashy just so they're at least clean looking and not sloughing off that lame outer material.

I think you might be mistaken on the strut bar. I did that in STX on street tires, but with big R-tires, turbo engine loading, and the mods to fit the engine I‘d think you’ve got some flexure going on without one. Not a criticism though. I see you have the OE strut bar mounting plates on there. It seemed odd without the bar.

John V

iTrader: (1)

I can't envision the load path that would make the bar beneficial but yeah I could be mistaken. I'll probably end up bolting it on at some point. I run the base plates on the shock towers because I like the extra load spreading they provide.

I shouldn't say someone gave me grief about the insulation, that's not really correct. Someone in SSM saw a pic of the engine bay with it removed, and asked what rule allowed me to remove it. I figured it was allowed under the 1lb rule, but that's only true if it needs to be removed to fit another allowed modification. Dunno. It's silly but a lot of solo rules are silly.

nlsolja123

Can I get some details on the ECU and wiring

John V

iTrader: (1)

What would you like to know? The wiring is pretty straightforward. I initially ran it using a stock NC Miata ECU... it fired up and ran great.

nlsolja123

I assume the NC ECU needs rewired, or is there a ecu jump adapter ?

John V

iTrader: (1)

You will need to rewire a bit of the engine bay to suit the ECU. Mostly it's moving around connections to the circuits in the fuse box. The RX-8 fuse box is organized a bit differently than the NC, there are different circuits.

Soravia

I'm thinking of doing the same. LFX costs too much for S2 body and I want a clean white Sport. Also lack of DSC means I will risk too much on the streets with all that power. I'm asking Joe from Dynotronics

I'm selling my 2013 Club with FM Supercharger to buy RX-8 S2 and swap in 2.5L MZR with cams and pistons. Planning to use oil pan,s intake, front subframe, transmission, wiring, ECU, cluster, ABS, all from NC Miata.
I think that will not have issue with firewall if I get NC front sub frame like you did.
Why the choice for DD gearbox? I think I can learn a few things from your setup, perhaps buy some left over items

TeamRX8

iTrader: (25)

just curious why you’d choose an S2 over an S1?

Soravia

Newer car. It will be my DD so I want nicer paint, interior, etc. My Super20 is on FB now but it will go live on Cars and Bids soon. Then I'll have to take it down every where else.

John V

iTrader: (1)

1) The MX-5 oil pan is not usable. The front portion of the pan is too deep and interferes with the steering rack and the front crossmember on the subframe. My initial plan was to section the oil pan and weld it back together, but then I came across a baffled, fabricated oil pan for the Duratec (apparently made by a Ford Ranger enthusiast in small quantities), and I went with that. There are some similar oil pans now available overseas that have a shallow front "sump" area.
2) The stock NC subframe is usable, but you'll have to cut a big notch out of the front. Remember the engine is moved forward on the subframe about four inches relative to where it would be in an NC (otherwise you have to cut a big hole in the RX-8's firewall, and remove the heater core... none of that is any fun). The V8R tubular subframe certainly works. It has some quality-control problems, or at least mine did.
3) You do not want the NC's ABS.
4) The NC gearbox will not work. The shifter would be located roughly where the ashtray is on the RX-8. I contemplated making a severely bent shifter to relocate it rearwards but those gearboxes are also not very strong, so I went with a more durable solution, that being the FD RX-7 5-speed. It would be the perfect solution for a street / track car that doesn't see any drag launches. Honestly for a street car I would strongly consider using the 8-speed auto used in the latest BMWs / Supra. There is now a fellow making an adapter to bolt one to a Duratec/MZR
5) Regardless of what subframe, gearbox, etc, the biggest problem is the shape of the RX-8 engine bay. Rotaries are short and squat. Four cylinders are tall and long. If you use a slim rear water outlet and don't cut or bash the firewall, with the engine as far back as it can go the front pulley is directly over the top of the high pressure line at the NC power steering rack. Furthermore with the slimmest oil pan you can fabricate, the oil pan starts to interfere with the driver's side power steering rack fastener. And the rear of the valve cover interferes with the middle portion of the cowl.

I stared at all of this for probably six months before just deciding to cut the cowl. There's no other way around it.

Bwek

this is what it looks like when you use all NC Parts, you will Not be able to keep the HVAC, it however will Line up the shifter, you can use the rx8 drive shaft, and the PPF sorta bolts up.

John V

iTrader: (1)

That is the stuff of nightmares

Bwek

other than the hole it was super straight forward, it used all oem miata NC rad lines, rad etc etc, even the NC Cluster basically bolted into the rx8 dash, sadly i gave this thing up and just went and bought a new car lol

John V

iTrader: (1)

Why bother with the NC cluster? The NC computer runs the RX-8 cluster perfectly fine.

I just can't fathom cutting a huge hole in the firewall, removing the HVAC, and being like... "This is fine"

Bwek

Never got far enough to try either one and at the time i thought it was necessary so i don't get any check engine lights for not have EPAS

TeamRX8

iTrader: (25)

well at least you can have easy access to all that stuff at the back of the motor

would that be SM legal?

.

John V

iTrader: (1)

Bwek

at this point just buy an NC miata lol