JCH13 - Turbo Miata Build/Auto-X Prep - UPDATE 4/29/2011 MOAR VIDEO!

[JCH13]

Wow nice link on the kit. I tried to get quotes to get a 1.8L from a NB I wrecked to get swapped in to my previous 95 miata and one shop wouldn't do it and another one wanted $4k.

It's definitely eating the oil. It even sputters out of the exhaust when I first turn the engine over. There's also soot over the rear bumper where the exhaust is.

That strikes me as something in the head leaking oil (valve guides? maybe...) If it were the piston rings I don't think you'd get much, or any, on startup. But diagnosing oil leaks isn't something I have much experience with. Coolant leaks on the other hand... :sneaky:

 

[yhelothar]

That strikes me as something in the head leaking oil (valve guides? maybe...) If it were the piston rings I don't think you'd get much, or any, on startup. But diagnosing oil leaks isn't something I have much experience with. Coolant leaks on the other hand... :sneaky:

leaky leaky... I'm just gonna sell it as is...
Can't really lose when you got it for $1100.

 

[JCH13]

I finally got my the Miata registered yesterday with every intention of fixing the last few little things and brining it home last night. JLee decided to come along to lend a hand and to drive my Speed3 back.

It actually all came together pretty quickly, reassembling the wipers took less than half an hour. We then vacuumed and reassabled the interior, which also took less than half an hour. I then jammed the so-called "exhaust system" back on with a little sealer, and we fired it up, backed it out of the barn, and let it warm up for a bit while we finished packing all of the tools.

We then got into the Miata to take it for a quick joy ride before brining it home. It was about the shortest joyride in the history of twenty-somethings playing with cars. Just puttering down the driveway we hear: "sccrrrraaaappppeee.... clang... bangclangwangmangbang scccrrraaaaappppeee." We got about half-way out of the driveway when a big bump took out the "exhaust system" from the down-pipe back and it got dragged along for a few feet by the O2 sensor wire. D:

Fucked the joy ride, jacked up the car, readjusted the exhaust hanger (the one exhaust hanger) and reattached everything, and ever so carefully left to drive it back to my apartment.

After some mild-mannered driving, which lasted about 10 miles, JLee and I decided that we'd have a little fun as soon as the road split into two-lane traffic...

He laid into it in the Speed3 which immediately started pulling away because of it's fantastic low-end boost. My experience, because of the pretty huge turbo, went a little something like this:

2,000 RPM - Kay... I'm driving a Miata...

3,000 RPM - Kay... I'm driving a loud Miata...

4,000 RPM - Ohai 4psi of boost! Aren't you cute!

4,500 RPM - Satan? When did you join the party...aaaaauuuuuggghhh!!! :awe:

5,000 RPM - SAWEEET! SO GOOD! :awe:

6,000 RPM - holycrapholyshitholygodholymotherofgodsweetmarymotherofjesusthisthingisfast! :awe:

6,200 RPM - Wait... is that 15psi or 20psi I see on the boost gauge?

6,500 RPM - Definitely out of fuel capacity! STOPITSTOPITSTOPIT

By the end of a 2nd gear pull the Miata had basically unleashed the forces of Satan, was pulling insanely hard on the Speed3, caught up to it, then I got off the throttle as something very awesome but very not safe was happening with the boost. I think, as JLee suggested, that the wastegat actuator, which is at a somewhat awkward angle, is binding. Will post more as I sort things out!

 

[JCH13]

Also, checked it this morning, apparently there is a leak on the driver's side somewhere that will need some fixing... :hmm: well, it is a Miata...

 

[PseudoSport]

Nice to see you are enjoying the car. I’ll be keeping an eye on this thread.

Not sure if I forgot to mention it but the car also has a 1.8L diff, poly diff bushings, 4:10 gears, an RX7 clutch type limited slip shimmed for 150 lbs pre load and MazdaSpeed competition mounts.

If you ever have any questions about the car please let me know.

 

[JCH13]

Ordered: laptop and cable for tuning, and an in-car laptop mount. Should be pretty sweet!

Nice to see you are enjoying the car. I’ll be keeping an eye on this thread.

Not sure if I forgot to mention it but the car also has a 1.8L diff, poly diff bushings, 4:10 gears, an RX7 clutch type limited slip shimmed for 150 lbs pre load and MazdaSpeed competition mounts.

If you ever have any questions about the car please let me know.

That would explain how it feels so well-planted even with a lot of power.

 

[exdeath]

Make sure you reinforce your floor boards with that laptop in there :awe:

 

[TechBoyJK]

Get this head unit to fit the interior (it's black right?)
http://www.crutchfield.com/p_522JHD1...B.html?tp=5684

a fucking jensen... seriously? Unless they've changed in the past few years, their products are total shit.

 

[JCH13]

Make sure you reinforce your floor boards with that laptop in there :awe:

rofl

I think as long as I don't keep a bag of washers in my glove box I'll be okay.

 

[exdeath]

rofl

I think as long as I don't keep a bag of washers in my glove box I'll be okay.

LMAO

 

[exdeath]

So is this a built turbo block or a stock engine with a bolt on turbo that just saw 20 psi D:

 

[JCH13]

So is this a built turbo block or a stock engine with a bolt on turbo that just saw 20 psi D:

That's a good question. If memory serves the Miata engine, B6ZE(RS), gets most of it's components from a turbocharged engine (B6T I think, but don't quote me) so it's very boost friendly out of the box (it even has piston oil cooler/squirter jets). I have heard of around 15psi of boost being run on an engine with stock internals.

Now, the second part of the story is that there is not much distance on the boost gauge face between 15psi and 20psi, and I wasn't really looking that closely. If it was 15psi, that wouldn't be great, but not that bad either. If it was 20psi... well... I am amazed things didn't go 'splode.

I think when it comes time to work on tuning the MS I'm going to see if there's a way to do some sort of over-boost protection. Like retard timing and add tons of fuel if the boost gets too high. I might even add this directly into the fuel/spark maps.

 

[exdeath]

Adding fuel won't work if you over boost beyond the fuel system's capability. Cutting fuel entirely would be better. Can't go "lean" if there is nothing but air in the cylinder to begin with, and it will eliminate power to the turbine and drop boost near instantly. This is what OEM rev limiters and over boost protection does. Ask JLee about the fuel cut defender mod on his MR2

 

[JCH13]

Adding fuel won't work if you over boost beyond the fuel system's capability. Cutting fuel entirely would be better. Can't go "lean" if there is nothing but air in the cylinder to begin with.

Good point.

I was thinking that retarding the timing would serve to kill power and drop revs so the turbo couldn't create boost and also dump into lots of fuel to further kill power.

The snag with cutting fuel in the fuel map is that the MS does a weighted average of the four closest fuel or spark points (cells) and if one or two of those points say "0" then average can wind up being very lean, which we all know is bad.

If there was a routine separated from the fuel/spark maps that would kill the engine then the fuel cut would work... I should look into it.

 

[exdeath]

Overboost isn't something like knock or something to adjust and respond to real time while the engine continues pulling, its considered catastrophic failure outside normal operating parameters that should result in immediate termination of fuel/power.

Timing and fueling adjustments won't be enough to compensate fast enough for something like.... a stuck waste gate WOT

 

[JCH13]

Overboost isn't something like knock or something to adjust and respond to real time while the engine continues pulling, its considered catastrophic failure outside normal operating parameters that should result in immediate termination of fuel/power.

Timing and fueling adjustments won't be enough to compensate fast enough for something like.... a stuck waste gate WOT

Again, good point, I'll see what's to be done in MegaTune to prevent it!

 

[JCH13]

Sorted out the overboost issue, helps to have the waste gate actuator plumbed properly :hmm:

Video of an easy 0-60 run (no launch)

Boost comes on later than I'd like, probably going to switch to a smaller turbo, something in the GT2560R or GT2554R equivalent range.

Oil catch tank was overflowing with oil from when it over-boosted monday night... noticed it sloshing through the filter today. I'm going to drain it out, top off the sump, and see what happens now that the boost is sorted out.

 

[FuzzyDunlop]

good thing you let off there, you almost went plaid!

 

[exdeath]

High boost works wonders on PCV systems :awe:

 

[punjabiplaya]

Sorted out the overboost issue, helps to have the waste gate actuator plumbed properly

at least it was something easy and simple, whew

 

[ballmode]

Edmunds Insideline just posted #'s on their Miata that is S/C.

0-60 in just 6.8 seconds

but it pulls a 1.03 on the skidpad

 

[JCH13]

Edmunds Insideline just posted #'s on their Miata that is S/C.

0-60 in just 6.8 seconds

but it pulls a 1.03 on the skidpad

The S/C Miata's are usually doing something like 150rwhp, which is a lot better than stock, but not wildly fast. Turbo FM2 Hydra Miatas (turbo kit from flyin' miata) are good for 230 or 250rwhp (1.6L and 1.8L respectively) at 12PSI. Turbo is the way to go with small engines.

 

[PseudoSport]

On the passenger side of a 1.6L there should be a blocked off port with a rubber cap that can be used for an oil drain back for a catch can right above the oil pan next to the filter. I’ve seen some people install a drain from the catch can to that port so they don’t have to empty it.

 

[JCH13]

On the passenger side of a 1.6L there should be a blocked off port with a rubber cap that can be used for an oil drain back for a catch can right above the oil pan next to the filter. I’ve seen some people install a drain from the catch can to that port so they don’t have to empty it.

Sounds dangerously simple I'll take a look at it tonight.

 

[DivideBYZero]

That's a good question. If memory serves the Miata engine, B6ZE(RS), gets most of it's components from a turbocharged engine (B6T I think, but don't quote me) so it's very boost friendly out of the box (it even has piston oil cooler/squirter jets). I have heard of around 15psi of boost being run on an engine with stock internals.

Now, the second part of the story is that there is not much distance on the boost gauge face between 15psi and 20psi, and I wasn't really looking that closely. If it was 15psi, that wouldn't be great, but not that bad either. If it was 20psi... well... I am amazed things didn't go 'splode.

I think when it comes time to work on tuning the MS I'm going to see if there's a way to do some sort of over-boost protection. Like retard timing and add tons of fuel if the boost gets too high. I might even add this directly into the fuel/spark maps.

This is correct. It's the engine out of the 323 Turbo, minus the turbo, so you still get the beefed up rods/crank, etc of a turbo car. However, if my memory serves me well the NA car didn't come with piston oil spray, but the NB engines did. I could be wrong, though.