EPP

iTrader: (22)

I hate hearing of things like this. I wish you luck! Bob

chriswtx

iTrader: (5)

You running the ECS fuel system?? if you have an aftermarket fuel pressure regulator at the fuel rails, make sure you boost/manifold reference it. Under boost it will increase your fuel pressure which is what you need...

Pekka_Perkeles

The fuel system is from A&A and should be adequate for my engine. To my understanding Andy does not use boost-reference in the requlator. And even in the pics in his web-site, there's no vacuum/boost pipe in the requlator.

https://www.aandacorvette.com/cart/s...p?MainCatID=40



However, I did use boost-referenced approach this time for Andy's regulator that is after fuel rails and just before new return line, but it seems that I cannot increase fuel pressure over 62 psi. Perhaps this is because 2003+ FFS fuel system in C5 Corvette has it's own in-tank requlator for the original pump and it is somehow mixing things... Anyway, fuel pressure remained over 60 during dyno pulls, so that shouldn't be a problem, right?

chriswtx

iTrader: (5)

Yep,on my 2004 vette I have the external bosch and intank pump. I was running out of injector with the non referenced system and 60# injectors. Almost the same fuel setup as yours. I had to put a one way check valve on the feed line from the stock fuel tank to keep the Bosch from pushing fuel back into the fuel tank because of the stock intank pressure regulator. Now I'm referenced and see 70-75psi of fuel pressure under boost.... Put a check valve right there at the "T" and you can reference the regulator..It will help you injector duty cycle a bunch at your power level...

Pekka_Perkeles

Hey, BIG thanks for this advice!!!!!

What kind of check valve did you use?

chriswtx

iTrader: (5)

Earl's -6AN

Websy21

iTrader: (34)

Pistol whip that retard, holy **** I don't know much about tuning but omg is that brutal. All the best in the future though!

nvmy2000ss

iTrader: (17)

If I remember right you will need a tune before you try to drive with the 2 bar. If you are going to install the 2 bar while your there drill and tap the intake so you can drive the car to the tuner then swap out the map sensor when your there.
here are some pics


then you use a long enough vacumme hose to swap the two when you get to the tuner.

Pekka_Perkeles

Today I removed the heads to see what damage my incompetent, now ex-tuner was able to achieve with my forged 427. Well, it was kind of interesting, I have to say, and once again I need to trust you guys to give me proper advice, as in the continent I'm living we don't have too many LSx-specialists. So please advice what I should do. Let's go to the story itself.

Before removing heads I decided to do a compression test. This was the result, which made me wonder if I have some broken rings or leaking exhaust valves...:

Cylinder 1: 210 psi
Cylinder 2: 201 psi
Cylinder 3: 192 psi
Cylinder 4: 188 psi (this cylinder gave most misfires and had baddest plug)
Cylinder 5: 180 psi (second worst misfire in this cylinder)
Cylinder 6: 205 psi
Cylinder 7: 192 psi
Cylinder 8: 210 psi

After measuring pressure I removed the heads. And this was the worst cylinder, number 4. All other cylinders did look good, but this didn't:





Here's how the piston looks like. This is also the worst piston, most others look pretty ok:



In this image there's worst cylinder #4 in the right and then on the left there's #6 that looks like it has no damage at all:



This is cylinder #5, again I think that there's no damage, but still it had lowest PSI in compression test. So perhaps exhaust valve is damaged (although the car was running pretty well before I took the heads off):



This is the head with cylinder #2 and #4, again the worst cylinder/combustion chamber is #4 that is in the right side of the image:



Cyl #4, head "quench" area:



So what would you guys do? Install new Manley forged blower pistons? Or just smooth the area in Cyl. #4 and hope the best... I'm quite scared if my rings have survived in cyl 4. Or is it piston that has left those marks in the cylinder? Or rings?

MonochromeSS

iTrader: (1)

My car passed a leakdown test missing 1/5th of a ring land on #7, rings intact, ring land MIA.

Howie Felterbush

iTrader: (1)

For as much power that this setup is capable of, I cannot believe you are even messing with Tr6 plugs. Its a blow torch for this application.

Id start with an NGk 8 for one thing. Fix the fuel system and find another tuner. Find someone that knows how to read plugs to find the right heat range. Just because others have used Tr6 doesnt mean they are safe to use at the power level you're capable. Kinda like seeing someone jump off a cliff with no parachute. If someone told you to jump off a cliff would you do it?

ls1290

iTrader: (20)

The #4 cylinder is toast. The scratches/grooves in the wall are way too deep to save. The #5 cylinder is slightly better. The #4 piston is toast also. The gouges/nicks in the quench will create hot spots and cause detonation and misfires. The head chamber for cylinder 4 also has the same problems as the piston. The block/heads/pistons are junk IMO.

Keith

Pekka_Perkeles

Well, the pistons I agree, they are junk now. But for heads, as they are thick deck design by Edelbrock, how come milling the head surface and cleaning combustion chamber(s) would not solve the problem?

The block could be sleeved, I think, but before that I hope that the damage could be measured somehow. I guess I need to consult block machinist soon...

Thanks for the comments anyway!

Vetal

iTrader: (3)

Pekka are you from Finland?

OHSIXCTSV

pekka? umps tumps penumps. =]

calongo_SS

iTrader: (7)

You need a new tuner. After you get a new tuner you should probably still change a few things with the setup. I'd go to a colder plug & a 3 bar OS.

nuclearxp

I'd have to agree with everyone else. ANY tuner that sees a FI setup even start a WOT pull at 12.5 should have nixed the pull immediately.

1dirtyZ

iTrader: (1)

consult with a machineist regarding the scratches in the bores , i know pictures don't do justice to things like that , a machinist might deem that you just need a hone job.

heads can br resurfaced , but you should also check the valves and do a vaccume test at the machine shop just to make sure the heads are 100%

crashly

quote:
You don't have to pull the heads, do a leak down test and that will tell if there is something wrong. Sounds like you're ok though... but best to check with a leakdown test. Its really hard to tell what is going on without the actual tune file and log file. There is not much to tell from the pictures of the log you posted, other than what you stated


good start...
after the leak down, cut a oil filter , and see what is in there.
When i tip a plug, it messes up the bigend bearing on the same cylinder

you have toooo much cylinder pressure / temp

ash

SPRAYED 01

iTrader: (22)

I think your motor is fine. Ive melted plugs in the past when i was running nitrous. I never once had any issue with the plug breaking a piston or causing anymore damage.