Enron Exec

Ok guys, i am relieved to find out my motor wont be needing a rebuild. This was the reason why i made the thread asking for the costs of a built engine. I got off lucky this time. Rewind to Tuesday, I was racing a heavily modded WRX and i was watching this UPS truck and not the tach when i hit the fuel cut off in 3rd at WOT. Yea.. im pretty dumb. I shut it down and noticed the car running a lil ruff. I pull over to a gas station and see no smoke or oil. The car still ran, just slightly ruffer then usual... kinda like the time i had 2 coil packs swapped. I drove maybe 20 miles to a well known tuner shop, Lightspeed, and had Tom do a compression check. The next day, he said the compression was 160 over 4 of the cylinders, 158 in one, 162 in another. He said he even rotated the spark plugs around to make sure this was a true read. This was when he found the NGK 1 step colder plug in the #5 cylinder. The tip of the plug was bent to the center diode or core. So of course this ment no arch or spark and why i was running ruff. I also had a CEL light and it confirmed the problem, 305.

Any idea how in blue blazes this might have happened? Ive been asking techs around town and some said, my rods might have stretched, some say alot of heat and predetonation. I was getting some pinging above 6000 rpms now that the summer heat and humidity is back. A month back when it was maybe 60F the car ran perfect. Houston summers are hard on FI motors. Time to do something about the timming. Oh yea ... once again im a tard.

Oh yea, the car seems to be running fine now. I havent pushed it yet because im using a stock platinum plug in the #5 cylinder until the copper 1 step colder can be shipped in. Houston is all out of these plugs!

Sharif@Forged

iTrader: (92)

Dont worry, the piston didnt hit it. It was definately excessive detonation that bent it.....very common. But you are very lucky. Get your timing retarded.

Enron Exec

Im retarded.

And i was running 2 gallons of 104 octane from a local race track just a few days before. I think i had 2 gallons of 93 mixxed in with the race gas. Maybe the stock ECU added timming when i was on the race gas and then when i was on only pump 93, it caused more pinging?

Sharif@Forged

iTrader: (92)

Probably not. When technosquare and Cheston did their ECU research, they discovered the stock ECU has two maps. One for premium fuel (91 octane), and one for regular as a fall-back map. So the ECU is not optimized for fuels above 91 octane. With F/I it will certainly help you...but the ECU is not what caused the pinging. If you use 91 octane or 100octant, it will still use the same map.

And remember, your timing could be perfect one day and, and off the next, due to changes in weather, pressure...etc...etc.. Also give yourself an extra margin of safety...dial in some more retard/and or/more fuel...hehe...I am not calling you a retard...just telling you to retard.....

have you dynoed this bad boy yet with A/F?

Enron Exec

I must be retarded, or very lazy.

The car put down 357 rwhp SAE corrected with the dyno bay around 80F here in Houston. I think the AF was just under 12:1 until 6000 rpms where it began to richen up below 11.5:1 by redline. Torque was around 301 rw i think.

I like to call myself retarded becaue quite frankly i am!

Sharif@Forged

iTrader: (92)

Get yourself a little richer across the board. 12:1 is borderline in my opinion.

I'd like to see 11.5:1 almost across the board for safety purposes.

fluidz

you only have 355rwhp with a/f near 12:1????.........i am at 337rwhp at 7lbs of boost with my A/F 10.2:1-10.4:1..........why is the vortech so much more?

350Now

Enron Exec, apology what set-up do you have? I notice you stated 357rwhp but a 301 tq?

I am at 332rwhp and 319 tq at 5.6 psi with a very rich a/f sub 10 from 4.6K to redline.

Either way, I agree your fuel is a little high, I would also want to see 11.5:1 to redline.

Enron Exec

I just have the ATI kit, everything else is stock as far as power adders go. 350-360 rwhp is about right for 7lbs of boost. I cant decide if i want a custom exhaust setup of something like the Invidia or Borla.

350Now

Enron Exec.. thanks that makes sense a free flowing exhaust should bump the tq # up a bit.

12SecZ

Good news Enron, right on.

EJ had the same thing happen same cylinder too but he didn't have a timing issue and it was detonation on a dyno IIRC.

elektrik_juggernaut

pretty close...........yeah, i had my #6 close shut on me........the stock timing caused the detonation at about 6Krpms..........huge relief that it was just a spark plug.........after seeing all those motors popping i was seriously cr@pping my pantaloons

leemik

iTrader: (2)

No two cars are the same. No two dynos are the same. I have the ATI, I dyno about the same as enron exec but my A/F is around 10.7 at WOT.. all I have is the Borla TD exhaust..

--mike

SQUILL

You guys notice all the problems are #6 #5 cylinder related???

Be careful this is caused by the factory plenum design the #5-6 cylinders are getting 25 % more air than the #1 and 2 cylinders but the factory ecu cannot compensate for that.

This has been well documented and are quite a few threads about it here ... everyone that blew their motors stated either the #5 or #6 cylinder failed!!!!!

The shop ive been talking to about my future TT install wont even do it without an after market plenum...they are using the craworford plenum right now which has less than a 5% difference of air flow between all cylinders.

The two motors they have torn down to build up with forged internals both had tell tale signs of lean conditions in the #5 and #6 cylinders. I agree you need timing retard you retard (lol just kidding) especially with the procharger kit which has not addresed the timing at all and has toasted a few motors lately.

my recomendation would be to put an aftermarket plenum and dial back the timing after 4000 rpm in 500 rpm increments up to redline then you should have less problems dialing in a correct a/f ratio across the board and should be able to run 9lb pulleys safely if you wanted to!!!!

my .02

IceY2K1Max

iTrader: (1)

Hmmmnnn...sounds familar.

Is the #5 and #6 the last two cylinders/injectors on the fuel rail path, ie the farthest from the tank?

SQUILL

Here is a sweet drawing (lol) that should explain things a little better....

the crawoford plenum raises the height in the front of the plenum by one inch so that it is level and testing on the flow bench shows less than 5% difference per cylinder. Due to the increased height you cant use the factory strut bar buy crawford makes one that will work with their plenum.

leemik

iTrader: (2)

lol! photoshop 0wn3z j00!!




very effective picture otherwise

--mike

SQUILL

LOL! Dont hate just because i got mad MS Paint SKILLZ!