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-   -   Clicking noise/ low compresson on #1 (https://www.miataturbo.net/general-miata-chat-9/clicking-noise-low-compresson-1-a-24562/)

Chris Swearingen 08-20-2008 03:31 PM

Update: Give that man a cigar!

Originally Posted by AbeFM (Post 297259)
I sense an upgrade in your future!

The motor guy disassembled everything. No metal in the pan or anywhere else it shouldn't be. But he did find something interesting. I hope you are all setting down. I didn't just bend the #1 connecting rod, I bent ALL FOUR.
I will get pictures after I get all the parts back.

So to add to the collective wisdom: Stock '99 Miata rods will handle 200 HP, but at 225 to 250, bad things happen.

I have to have the motor ready to go for the Solo II National Championships in Topeka the 18th and 19th of September. That deadline really limits the options available to me.

I found out I couldn't buy a new built motor. No one got back to me on the used built motors that were for sale.

SO...

I called around looking for pieces and parts that were in stock. The good folks at Flyin Miata came through for me. They will ship the following this afternoon ( I ordered this morning)

Carrillo H-Beam rods
Weisco +1mm Pistons (9.0:1)
Oversized intake and exhaust valves
A valve spring kit
ATI Superdamper
145mm 6rib supercharger pulley for ATI damper

I don't know how much of a "build" thread I will be able to do. In the essence of time, I am having all the motor work done by a highly respected local motor builder. He mainly does big block chevy type stuff, but also does spec miata motors, and is crew chief for one of the MX-5 Cup teams, so he has seen a miata before.

I will keep you posted on the progress.

AbeFM 08-20-2008 03:55 PM

That sucks, but is good news. :-) A little pricey, but it should work. Too bad you can't put it all together yourself, it's fun when you have the time, and a lot cheaper obviously. Then again, compared to the price of the parts it won't be too bad.

I got some used H-beams a while ago, run '97 pistons for the lower compression.

The history, when I first turboed my '00, I put on a used FM-II kit. Had no boost gauge, an incompetent friend watching the LCD-map. The wastegate actuator was broken (didn't know this. I'd tested the HELL out of the EBC, but never the diaphram), and there was a bad ground on the ECU.

So long about 20 psi, the piggyback stops pulling spark altogether. Bent at least 3 rods, I stopped checking too close after I found one that was bent in two seperate axis. I was having piston-counterweight interference.

Got a set of used '97 rods and pistons, assembled - had a mutual mistake with FM which they were awesome and took care of - put it all together, and much later down the road, bent all of those.

At the time, I'd heard there's a different part number for the '99+ rods, some theories that the early rods are shot-peened or somehow treated, which the later cars were not. They both saw out-and-out abuse.

The last time around (still using the 9.0:1 '97 pistons) I got me some used carillo H-beams for cheap, like, <$500, and nothing that I know of has gone wrong since.

I don't think 200 hp is any magic number, I think it's bad tuning. People are making more than that, but you have to do it right, have reliably timing control - that's almost everything.

What ECU are you running? I thought it was a MS-I, meaning you're using the CAS sensor, and that can easily have 5 degrees of jitter.

If you're serious about making bigger power, you should really use a timing wheel. If that's not it, then, bad luck, but you'll have a bullet proof motor now so enjoy. :-)

Chris Swearingen 08-20-2008 04:16 PM

I would have been the first to admit if it was a tuning issue, however the car has seen hours of dyno time building that tune, was purposely tuned a little rich knowing we would be going to sea level, and showed no signs of any ignition events.

All that said, I was running an EMU which I had zero complaints about at 10-13 psi and 460cc injectors. When we upped the boost to 12-14 and moved to the 750cc injectors, things were good under hard acceleration, but we were having some problems modulating things effectively at partial throttle. No amount of dyno time was taking care of it. So I conned Joe into building me a MS-II to handle four primary functions I can't do with the EMU.
1) better control over the 750cc injectors at partial throttle
2) support for a flex fuel sensor to support various mixtures of e-85
3) the ability to drive a coil on plug setup and adjust dwell
4) accept input from the KnockSense MS and act on it


Edit: the MS and knocksense are both on my desk to be installed immediately after break in on the new motor

jayc72 08-20-2008 04:29 PM


So to add to the collective wisdom: Stock '99 Miata rods will handle 200 HP, but at 225 to 250, bad things happen.
That's a pretty bold statement to make, considering the number of people who are making that and more on stock parts. I'd take a long hard look at your tune before saying it was a mechanical failure. Just because you are running rich doesn't make it safe. I'm sure it was knocking like a mofo, you just didn't hear it. I wonder what your AIT was when it failed.

Good luck to you!

Chris Swearingen 08-20-2008 04:45 PM


Originally Posted by jayc72 (Post 298808)
That's a pretty bold statement to make, considering the number of people who are making that and more on stock parts. I'd take a long hard look at your tune before saying it was a mechanical failure. Just because you are running rich doesn't make it safe. I'm sure it was knocking like a mofo, you just didn't hear it. I wonder what your AIT was when it failed.

Good luck to you!

You are probably right, and I defer to your greater experience, please send me a list of the folks making in excess of 225 rwhp on stock '99 rods and I will apologize to each of them.

jayc72 08-20-2008 04:58 PM


Originally Posted by Chris Swearingen (Post 298814)
You are probably right, and I defer to your greater experience, please send me a list of the folks making in excess of 225 rwhp on stock '99 rods and I will apologize to each of them.

There are a lot of dyno charts (take them for what they are) floating around out there showing in excess of 225whp on a stock 99 motor. You'll have to compile your own list of people you've offended, I'm too lazy.

Are the '99 rods unique? Or are they the same as the rods from a (for example) 2001?

And I don't have greater experience, you see I'm still on my original '93 motor :)

AbeFM 08-20-2008 07:55 PM

Heh - I'm pretty sure I was running on them, for a long time!

Oh, wait, those were '97 rods. But still, I ran SEVERAL blocks under high boost on '00 rods. :-)

Nonetheless, FMs claim is you need better tuning to pull it off.

All the fuel in the world won't save you from bad timing!

I still have SERIOUS misgivings about this CAS sensor on your motor. You're putting way too much money into this to not use a trigger wheel. A stock '99 wheel would be fine, a $30 36-1 wheel would be even better.

But, maybe your machinist will have a discount if you do two builds in the same month. :-)

Chris Swearingen 08-26-2008 08:24 PM

Got the old rods and pistons back from the engine builder today.

http://www.systemstrategies.com/miat...entrod_005.jpg
http://www.systemstrategies.com/miat...entrod_006.jpg

AbeFM 08-26-2008 08:43 PM

Any underskirt damage? I saw it either on the skirts, or on the wrist-pin-holder, whatever you call that web of material.

They look so familiar. :-) Anyway, good luck with the build.

M-Tuned 08-26-2008 09:12 PM

Always seems to be number 1 cylinder (worst) on a 99-05 when using a stock Fuel Rail. I know I sell fuel rails, but I would recommend the upgrade, especially when everything is out of the car!

There are a bunch of people running 250hp+ on 99 engines! I was at 199hp at 9 psi and I just turned it up to 10.5psi on the weekend. Probably go more soon.

RotorNutFD3S 08-27-2008 10:46 AM

Wow, that #1 looks almost as bad as mine! Of course, mine was bent so badly that the wrist pin sleeve was contacting the crank counterweight and stopped movement altogether.

AbeFM 08-27-2008 01:07 PM


Originally Posted by Marc@M-Tuned.com (Post 301340)
Always seems to be number 1 cylinder (worst) on a 99-05 when using a stock Fuel Rail. I know I sell fuel rails, but I would recommend the upgrade, especially when everything is out of the car!

Got a selection of dual feed fuel rail blown motors whose rods you can show us? After I see five or six bent rods which are evenly distributed where they were running dual feed, it'd be a much more convincing argument.

After all, all the miatas I've seen with bent rods were running rubber tires, perhaps we should change that too? :-P

http://abefm.smugmug.com/photos/126429973_4z5wG-M.jpg

Tell me which rail I was running here...

AbeFM 08-27-2008 01:16 PM

Just for eye candy:

http://abefm.smugmug.com/photos/54089787_uwLjD-L.jpg

And from the side:

http://abefm.smugmug.com/photos/54089683_dCBjH-M.jpg

Yep, that rod has three bends in it, in two axis. Pretty destroyed!
Not sure* what order they were in the motor, though, and there was a timing issue, so it's not a good "rail" test. The other post, though, was from running lean, I believe.

Oh, one more from this first rebuild:

http://abefm.smugmug.com/photos/54089795_pNZ4h-M.jpg



*Turns out it was #3 that got the worst of it this time. Found a pic in the block.

ArtieParty 08-27-2008 02:43 PM

To the OP: What were your intake temps? Are you using an intercooler at 10psi? I dont remember seeing anything about an intercooler there.


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