patsmx5

iTrader: (16)

I am, it's not being driving till that happens, and a cat/muffler are installed. I just put new plugs in it too so I can monitor those for any detonation.

Also muffler came in today, jesus christ this thing is gigantic. It's not 5x11, it's 6x11.25. This thing is going to hang very low in the rear, I'm afraid it's gonna drag the ground if I launch too hard.

deezums

iTrader: (3)

I have to see this. No way you fit that thing, even if you can dump the turbo straight into it. Plus a cat, and 02 sensor that won't melt, where is this all going?

codrus

Rear mount turbo, front mount muffler.

--Ian

patsmx5

iTrader: (16)

Two O2 sensors, one before, one after cat.

But yeah, this is going to be almost impossible. It's going to hang low, no way around it.

Savington

iTrader: (31)

If it were my setup, I would run a pair of O2s, one in the normal end-of-DP location, the other 6" behind the rear turbo. Measure backpressure next to the first O2, compare readings for a better idea of what true AFRs are under cruise/boost.

Then again, I think I would just run a 7163, make similar power, and have it spool much better

patsmx5

iTrader: (16)

I'll check, but 99.8% sure that won't work.

Magnaflow said this was a 5x11 muffler, uh.

Thanks, I thought about doing that with the O2's, but I don't have two widebands.

Are you running a 7163, and making similar power and spooling much better? What are your numbers?

18psi

iTrader: (76)

"in theory"

all of us can easily make 500whp in theory


....though I think we'll actually see a 7163 put to work very soon on a miata

Girz0r

iTrader: (1)

I'm just waiting to see the tacoburritonsalsa mani replaced with TSE/EFR goodness...

18psi

iTrader: (76)

I heard the chinchillas max out at 69psi

But anyways, is the car completely out of fuel now? at 500ish?

TurboTim

iTrader: (9)

I made one for ~$50. Honda streetbike gerotor pump and razor scooter motor. I made mine to prime the engine with oil before starting, but it would work well for scavenge with a much smaller motor.






Turns out however that BMW's use little cute electric scavenge motors on their cars, tiny gerotor pumps. They didn't flow enough to produce pressure for my application, but would probably work great here.

Savington

iTrader: (31)

No, but Soviet made similar power (484/404 Dynojet uncorrected) with better low end (200ft.lb@3100rpm IIRC), and he did it on an unported '99 head, and that was an EFR6758, which has about 75whp less compressor than the 7163 does.

patsmx5

iTrader: (16)

Yeah that's what I figured.
Why replace the manifold or turbo? Both are working pretty well so far, I'm actually happy with it.

Yes, at 60 PSI base (dropping to about 5 PSI from that at 38 PSI) I'm at 100% duty on 5 1,000cc injectors. With 17.9* of timing. 500ish indeed.

patsmx5

iTrader: (16)

Thanks Tim! I'll look into that. Do you happen to know what vehicle, or purpose that pump is usually used for on a BMW?

patsmx5

iTrader: (16)

Cool. I'm won't be surprised if a turbo that cost as much as my entire setup spools better by a few hundred RPMs. That's to be expected and I'm ok with that.

EDIT: Just realized you quoted uncorrected (bigger) numbers and a different turbo too.....

mmmjesse

isnt it warm enough yet in houston to hit the track? i would love to see some times.

patsmx5

iTrader: (16)

Already answered that, but yes when it's sorted and the track is dry I'll be there. I had some parts come in yesterday I need to install to fix an oil leak in the rear turbo. Hopefully be there friday.

deezums

iTrader: (3)

That's way too cool, also good info on the BMW pump. Google seems to think they come off M cars transmission oil cooler loops. ~$200 on ebay used, not too bad.

fivehundredton

Don't laugh, I've heard of this: Do you think orienting all of your plug tips a certain direction would help with your spark issue? Might be a better direction than another in the combustion chamber turbulence....

Mobius

iTrader: (2)

Anybody wanting to copy this build because they want a cheap turbo build on a budget is in for a ginormous bucket of fail. The level of custom fabrication here is high even for mt.net custom builds.

Pat != avg cheap turbo miata owner (1800 hrs of welding experience, anyone?)

There are ways to turbo a miata cheaply, and there are ways to turbo a miata effectively. The number of people who can do both is extremely small.

fivehundredton

^ What he said. If you can't sort of pick up on this, I wonder..