Turbo Detonation pics

WideOpenThrottle · Post by **WideOpenThrottle** » Tue Nov 01, 2011 4:36 pm

My engine breathing has increased dramatically!

Two stuffed vavles & minor detonation on the piston tops...i think another engine is on the cards!

sprsta · Post by **sprsta** » Tue Nov 01, 2011 5:51 pm

holey moley

Angreal · Post by **Angreal** » Tue Nov 01, 2011 5:56 pm

As my Russian friend who loves to understate everything would say... That's not good.

Gravelben · Post by **Gravelben** » Tue Nov 01, 2011 7:10 pm

Less than ideal...

SLYDIT · Post by **SLYDIT** » Wed Nov 02, 2011 7:24 pm

the pistons dont look that bad on the tops...ive seen fiat twin cams that look like the pistons have been shot peened....throw a ported head on it and itll be good for another hundy!

is that the exhaust valves that have shattered???do you know what your exhaust gas temps are? i know i cooked some valve seals when a slight tuning glitch meant i was running really lean at low throttle...EGT's must have been sky high...

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Nov 02, 2011 8:26 pm

SLYDIT wrote:the pistons dont look that bad on the tops...ive seen fiat twin cams that look like the pistons have been shot peened....throw a ported head on it and itll be good for another hundy!

is that the exhaust valves that have shattered???do you know what your exhaust gas temps are? i know i cooked some valve seals when a slight tuning glitch meant i was running really lean at low throttle...EGT's must have been sky high...

Yep...both exhaust valves----got the pistons out today & one has minor top wall scoring, while another is quite bad.
Incidentally there is only some minor cylinder scoring & no lip around the tops so not bad really for a 280k engine.Will measure the cylinders for square & wear soon & decide which route to go from there!

Must have been hot in there but why only two crapped out? were the injectors running lean? Have just read that it could be the case from Flyin Miata as 4 is the usual culprit something to do with the fuel rail being fed closest to #1 which gets the most?

SLYDIT · Post by **SLYDIT** » Wed Nov 02, 2011 10:03 pm

four and three usually go as they are at the end of the fuel rail.(hence why i did the dual feed modification)
but also #4 runs much hotter than the other cylinders as the water flow through the block is pretty uneven. Originally the B6 block as used in the 323 has the water going in at the front and out at the back... but in the mx5 they made the "out" at the front too for packaging reasons.
the only real water flow that #4 gets is assisted by the heater core pulling some water from the back of the head...
this is why some high HP guys do the coolant re-route mod which returns the thermostat to the back of the engine then runs a new pipe all the way to the radiator so the block gets a true diagonal water flow path.

oh thats also why its a REALLY bad idea to plug your heater hoses if your heater core leaks because your engine is on borrowed time...

WideOpenThrottle · Post by **WideOpenThrottle** » Thu Nov 03, 2011 8:06 am

The water cooling probably had a lot to do with it as well as at the end of the back staight my temp gauge was getting up to 3/4 & on the final run when something 'gave' the temp was on high!

SLYDIT · Post by **SLYDIT** » Thu Nov 03, 2011 7:10 pm

whats your exact setup regarding fuel and timing???
do you have your ignition retarded?
if so by how much?
Do you have an oxygen sensor clamp? (voltage clamp)??

if your running a bit lean and too retarded you are going to be putting a heap of heat into the engine and not power...

looks like a megasquirt may be a good investment now???

i think minimum you need for a turbo piggyback system is a dual feed rail and an O2 clamp so your af ratios dont go all over the place below 4500rpm

WideOpenThrottle · Post by **WideOpenThrottle** » Thu Nov 03, 2011 8:49 pm

Reading from their catalogue-quote-'it extends the injector pulse width under boost to deliver more fuel-no fuel pumps,pressure regulators or injector changes are necessary-its limited by the size of the injector-the 1990-97 cars cant handle as much boost but theres still enough room to run 6-8 psi OR SO!-depending on the system.-Its easily adjustable [yeah right]!! so you can get your perfect fuel curve for your set-up.-It incorporates one of our O2 signal modifiers to prevent the stock ecu from pulling fuel when making boost at partial throttle-this is safer for your engine and provides a smoother ride.' un-quote.

I was running around 2 degrees timing as the tuning instructions indicated less is better to safe-guard against knock! They advise to run 6 degrees or less at 6-8 psi.

I get the feeling larger injectors & a dyno tune may have avoided the meltdown - but then i am still on a learning curve for now....ideally a stand-alone ECU & to get rid of the AFM is possibly on the cards depending on getting it all back together & seeing if its worth running 10psi with the box as i dont think i can be happy with less boost[it just wont be so much fun]

sprsta · Post by **sprsta** » Thu Nov 03, 2011 8:54 pm

http://www.trademe.co.nz/Browse/Listing ... =418977172

buy this!!!
it will help

SLYDIT · Post by **SLYDIT** » Fri Nov 04, 2011 7:42 pm

i'd be getting a new ecu..
you dont want to have to rebuild ANOTHER engine.

the engine control unit you have is way out of its depth at the boost you want to run.

the megasquirt pnp is the best value thing out there at the moment...pretty much the first thing to get now for the turbo crowd..its such good value for money.

sprsta · Post by **sprsta** » Fri Nov 04, 2011 8:07 pm

i wasnt even thinking of turbocharging mine until i happened to stumble across a miatalink
DIY AUTOTUNE is your friend for turbo on a budget

WideOpenThrottle · Post by **WideOpenThrottle** » Fri Nov 04, 2011 8:53 pm

Cheers guys- anew ECU is probably on the cards but all in good time!

RMS · Post by **RMS** » Sat Nov 05, 2011 9:46 pm

I can vouch for DIYAUTOTUNE. Especially with the exchange rate at the moment.

I think I paid around $600NZ landed for the DIYPNP. DIYPNP is an MS2 system and while there is the MS3 now I don't think it's worth it unless you've got a specific application that requires it or you're more interested in playing with ECU's than driving your car

The DIYPNP is cheap, easy to build and has everything you need to run the car properly.

SLYDIT · Post by **SLYDIT** » Sun Nov 06, 2011 11:09 am

I only wish it was available when i built my turbo system...

Turbo Detonation pics

Turbo Detonation pics

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