phenixmt

Not yet...
I will make a dyno run in spring time. Then we will can compare to roots and rotrex 's boost, Hp and torque curves.

my boost is not reaching more than 8psi because I must have a leak in my new piping setup. I will fix this later.

I've started my engine rebuild during this winter.

oreo

Seeing less boost, is normal when you add an intercooler(with a SC). When the air cools the density goes up, and the pressure goes down. Check your datalogs for injector pulse width. If your pulse widths have stayed the same, or increased, without a change in AFR, then you don't have a leak.

falcon

iTrader: (13)

With all those couplers I would still do a leak test. I have piping routed almost the same with a ton of couplers and I was leaking a tiny tiny bit and never knew it until I did a boost leak test.

phenixmt

Yes, before IC installed, I was running 10psi at 5000rpm. Now I've got 8psi. I'm aware about air pressure loss. But I've check my piping after a drive and I find "condensation" on some edges of couplers.

falcon

iTrader: (13)

After looking at some photos... you need to invest in t-bolt clamps. The worm drive clamps are useless.

phenixmt

Well, I bought some T clamps.

But at the intake manifold, I have a silicon hose (grey) and it is more slim than the others and my T clamp can hold it tight enough. So I've put a worm clamp.
I need a smaller T clamp or a new silicon hose (4 ply or something) for it.

You're right, I will go full T clamp in the future

phenixmt

Engine is out for rebuild!

phenixmt

Engine open but big surprise...



rings broken



And 3 pistons damaged





I was planning to keep the OEM pistons for the rebuild... :(

TravisR

iTrader: (9)

That is so strange looking... Your secondary compression rings show much less damage, and no extruding the groove out as in the top ring. Its probably a lean condition with some deto causing that.

phenixmt

Thanks for you analyse

Here's another picture




For Info:
-rev limiter set at 5000rpm
-100miles done with the supercharger
-max boost 8psi
-AFR 10 at full throttle

Maybe rings were like this for before...

TravisR

iTrader: (9)

Picture of top of pistion? It looks like you can see some pocking of the aluminum near the top on the side which would indicate the piston was overheated. Again excessive lean condition indication. Still I've never seen piston ring do that to the top Lan. My first thought was who assembled this thing, but from your post it looks like Mazda did it!

phenixmt

Piston n°1 (ring OK)



Piston n°2 (ring KO)



Uploaded with ImageShack.us

sixshooter

iTrader: (12)

Those little light colored spots indicate detonation. What were you using to control the spark timing when the engine was in boost?

hf-mx5t

nice. but why,.. on my golf 2 rallye, it was removed and a autorotor screw type sc installed instead. much better(but noisy as nothinge else)

phenixmt

detonations... maybe when I was running without intercooler. Manifold's air intake was so hot.
I use 98 octane gasoline but it was not enough to prevent detonations at this time.

richyvrlimited

iTrader: (1)

Temp is pretty irrelevant, you should still be able to tune the car to not det.

I've had extended 150degC intake temps on track, pulled the head and not a hint of detonation.

phenixmt

Well, I'm confused.

I though I was running in a kind of secure mode (8psi, 10 AFR, 5000rpm, 10 BTDC). So I don't know why.

Any ideas?

phenixmt

I realise that my spakplugs maybe a bit responsible, they're maybe too hot.
I will order NGK bkr7e-11

richyvrlimited

iTrader: (1)

Did you tune whilst listening for det? Or just assume that it was all OK?

phenixmt

I didn't make any tuning yet. Only use theory.
I though old engine could handle 100miles like this.

Here, was the plan:

-Finish the install of the supercharger,
-rebuild the engine before going further. (it was needed...)
-make fuel and spark tuning

Maybe engine was "fragile" before supercharging it