Forrest95M

Alright so today I'm having a minor panic attack about the health of my motor. I finished my exhaust except for a vband leak somewhere, doesn't help that I stripped one of them. The exhaust doesnt contact anywhere but comes damn close to the trans and subframe. Around 1/4 of an inch. Again trying to trace the leak on my down pipe and more water in the exhaust system? Also when starting up it runs fine when my wideband is on heater but once it warms up it leans out and it dies. Which I think is the leak before the o2 sensor so oxygen is present=lean. Is it a problem to lean out at idle? So some minor ms problems to sort out like idle control and fan control and trying to get autotune going.








The only thing else I did engine wise is switch to a 1.6 bk6r plug from the bk5r plug. Yes the downpipe is rough but it moves gases. Exhaust is 2.5 inch straight to a thrust muffler.

TwoTone

I wish i could help diagnose the problem. Lets just say I'm very jealous that you already have your turbo stuff installed. My cars a lawn ornament till i replace the clutch

Forrest95M

Didn't realize how much I suck at pictures. So far the car is running and driving, to and from school. Tuning strategy is good afr's via ve analize, which I love btw. As well as a set of Det can headphones. Still getting boost creep which prevents a full wot throttle run. Cashed out on Dremel bits and will do a nice port job tomorrow. Stock clutch isn't loving it, so the beefy act clutch will be going in soon. Also new england goes from 65 degrees on april 3rd to 4 inches of snow on april 4th and 5th, god (or whatever you think it acceptable here) hates miatas. So next purchase will be some Kosei K8R's 15x8 from tire rack as well as a set of Kumho ecsta v720's in 205 for a summer tire, when ever it comes.












So what I originally wanted this build to be, and what it will be, is very similar to tekel's 95 turbo. A cheap churbo street car that has good suspension, brakes, tires, and power. So I think its pretty close to that

shuiend

iTrader: (24)

You want carbide bits for the dremel. Check my GB thread, sonofthehill, deezums, and nigelt's build threads for pictures on the type of porting you need to do. Basically you need to enlarge the wastegate hole a good amount.

sonofthehill

iTrader: (1)

Ok I can't resist, as an SF native who survived 4 harsh New England winters and is happy to be back in sunny California.
The universe, unicorn, god or whatever loves miatas he just hates New England.

Forrest95M

Thanks Lars, Ill check that out. BTW the waste gate on the turbo IIRC is 8 psi right?

Forrest95M

When the car was still NA, we had a 70 degree christmas, drove the damn thing a lot with the top down. Forecasts shows 60 tomorrow and then more snow next week

curly

iTrader: (25)

You don't need to port the waste gate, you need a new downpipe. Ew.

Forrest95M

its been redone since then, the welder was set up half assed that was a test fit, everything got redone and the vband set up was moved down. Grounded and had some real welds on it

deezums

iTrader: (3)

I think Curly might not understand how tight the shelf is there with that tacoburrito T3.

Still some pretty shitty looking bends, but I guess it fits...

Forrest95M

Like I said its since been redone, I used a similar bend just because of how tight it is. There is a blurred line on what impedes flow and what doesn't. What did yours look like? I could find any pictures on your build thread?

shuiend

iTrader: (24)

Yeah the DP definitely is not good, but even barring that the wastegate needs to be ported.

shuiend

iTrader: (24)

1.6 tacotaco is different then the 1.8 tacotaco. 1.6 one is much easier to build a down pipe for. I bet deezums down pipe looks just about exactly as the ones in my setup.

deezums

iTrader: (3)

Mine was a lot easier, the 1.6 manifold has the turbo like three inches forward of the 1.8 manifold, and it's up a lot higher, too.

It's why I'm having Lars make me a manifold for my 1.8, his manifolds are closer to the 1.6 tacotaco. I won't have to change my downpipe much at all.

But here's mine...

https://www.miataturbo.net/build-thr...3/#post1184331

https://www.miataturbo.net/build-thr...6/#post1214480

bahurd

iTrader: (8)

If I had time I'd measure both for you. I have the 1.6 manifold (like yours) and the MK 1.8 manifold. Visually they look pretty damn close.

Forrest95M

still hitting over boost with a mild port job, will pull it this weekend and go at it again. What is the wastegate setting for these turbos?

deezums

iTrader: (3)

It depends on the preload you put on the wastegate can, or if it's binding...

Forrest95M

My other suspicions include the waste gate being higher than the rest, when I bought this I couldn't find a number. My waste gate reading of the comp housing of the turbo. Or something else. Preload should be zero to standard

deezums

iTrader: (3)

Thanks for the offer, but I'll manage to mod my downpipe to work without measuring. I've had Lars check for me too already

You should be able to set the wastegate preload loose enough to hear it rattle around at idle, if it still overboosts then you either need porting or a new wastegate can.

You could also use a bike pump to check it yourself if you wanted. It should be around 7-10 psi or so.

sonofthehill

iTrader: (1)

A bike pump is a good tool for wastegate testing. I recently rigged one up to find the max and min duty cycle of my ebc solenoid. It was very easy to see on the gauge, 7% closed, 98% open @ 19.5hz for those who want to know.