ihiryu

MSM stock turbo
2.5" exhaust,
FMIC
FM Intake and TB
MS3
RX8 420cc
93 Octane

Running 14 PSI

18psi

iTrader: (76)

should be at limit or close to it
of the rods and turbo

ihiryu

So det cans are the next step then.

Would it possible to see your timing map on E85? I would just like to compare the two.

18psi

iTrader: (76)

in boost it's similar to yours, maybe 1 degree less in midrange. I also only ran 10.5-11psi because I'm conservative and that turbo won't last long at 14

ihiryu

Whoa, even though you're running e85? That makes me want to dial my timing back now.

18psi

iTrader: (76)

Well my map is very conservative for e85, I bet I can bump the whole top half by 5* and not see knock. But knock was not my concern with e85.
The reason I didn't run more is again because of the rods. IIRC I was running 13.5* midrange tapering to 16-18 up top, and put down 209wtq on a low reading mustang dyno at 11psi

Greddygallant ran same boost as you and even less timing and his rods were bent when they took that engine apart. Also his turbo died a while ago.

ihiryu

So pull out another degree of timing in the middle, so your recommendation is pulling out another degree from 4-6000 RPM's, above the 100 KPa mark?

arghx7

The more timing you run, the higher your cylinder pressure, even if it's not knocking. That's just how combustion works. So whatever is the weak point will break.

Schuyler

iTrader: (1)

<p>I'm going to throw this out there. My motor has all the symptoms of bent rods, and I will be confirming/disproving that this weekend. But, here is my spark map. I was holding 12psi, spiking to 14/15 on spool.</p><p>EDIT: T25</p><p>EDITEDIT: 93 Octane</p><p><img src="http://cimg3.ibsrv.net/gimg/www.miataturbo.net-vbulletin/1043x733/80-ssznzg3_b0f04f307fc56d8f9fc8eca052a5cfe4a2a19862.p ng" title="" /><br /><br />&nbsp;</p>

ihiryu

Lol and what are these symptoms

Braineack

iTrader: (62)

i ran more than that for years

18psi

iTrader: (76)

and a local buddy made 350whp on stock block for a while too.
exception, not rule

Schuyler

iTrader: (1)

<p></p><p>Lower compression (by 30-40psi) on three cylinders than 2 days prior, and no compression on 1.</p>

ihiryu

I dialed it back some, wait to get on the dyno and really check for detonation. I made some detcans, but for some reason I don't trust it. I'll probably use my detcans and what they have there on the dyno to just see if they both sound the same.

Schuyler

iTrader: (1)

<p></p><p>You'll bend rods without det.</p>

Braineack

iTrader: (62)

he's retarded it 10° over stock just as he enters boost.

my setup was never the exception--mine was as plain-jane and repeatable as it comes. Also, every MS I've built (hundreds) pretty much runs my spark map as sent.

18psi

iTrader: (76)

ok
this looks normal then

Braineack

iTrader: (62)

Dude are you really going to go down this path with me?

let's just say that 16° at 15psi is a good safe limit (which I think it is). You think that retarding so heavily the minute you start getting into positive pressure is something ideal? there's no reason to retard you spark that much at 90° unless the goal is reducing torque and hindering performance--especially given how slow the MSM turbo spools.

Even the MSM basemap for the MSPNP-Pro is much more advanced than that... and I'm pretty sure the last thing DIY wants is a customerbase like FFS with blown motors (plus they do testing on their in-house dyno). you think I want to deal with that either?

Plus if you're at the limit to bending rods based on a spark table alone, I'd urge you to reduce the boost not just a few degrees of spark.


open a spool log in MLV. Open your MSQ in the tuning panel. watch the plot as your travel through the spark map. that map is heavily retarded as the turbo is trying to spool, and then fairly retarded through the entire time in boost.

even outside of boost, look how retarded it is even at 4K and cruise...WAY less oem. I would cruise at a timing mark where his highest value that he'll never ever hit is set.

18psi

iTrader: (76)

I didn't even look at the rest of this spark map, I was just commenting on the high load area. 14psi and 14-15* will bend rods, even on the baby hairdrier of the msm. I only say that because I've seen it, both here and on M-S.

PS: both DIY's and your basemaps ping on CA 91oct. past 12psi too. I think I even have logs of this, it was so evident I actually heard it inside the car.

Braineack

iTrader: (62)

That's sad.