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gonna go check out the car wednesday at corksport. I will respond with more info then.

cjthor dude! hows your car doing? any updates?

94blaze1.6 wrote:cjthor dude! hows your car doing? any updates?

Got a call and its finally done...just gotta make time to go get it now...and that means getting a ride there..prolly going to get it next wednesday.

So what did they end up doing? Did they replace the block or were they able to salvage it? I hope all goes well. Keep us posted

go go gadget boost!

94blaze1.6 wrote:So what did they end up doing? Did they replace the block or were they able to salvage it? I hope all goes well. Keep us posted

They were able to put a hone on the cylinders and they are fine. New pistons and rings... They were still not able to time the cams with degree wheels...and im kinda bummed about that part.

Gonna pic up the ride tomorrow...as long as I can get a ride to Vancouver tomorrow am....and the snow goes away!!

Not bad...this is BEFORE the engine was fixed...gotta put a few miles on her before the dyno run.. This was with number 3 cylinder 40lbs low and the cams waaaaayyyy outta wack

looks good, how much boost are you running? u have a gt28 rite? did corksport every get your cams degreed correctly? do u have a new dyno after the rebuild?

cjthor wrote:[Not bad...this is BEFORE the engine was fixed...gotta put a few miles on her before the dyno run.. This was with number 3 cylinder 40lbs low and the cams waaaaayyyy outta wack

This is BEFORE as I cant get another dyno tune til i break in the motor...gt2871R runnin i think was 18lbs on pump gas.gonna try 100 octane next time. Cams are an entirely different story...They are close..they werent able to get cam degree wheels.

Pump gas is fine...I've pushed 93oct. to 30psi...just watch the EGT's and the AFR's. At full boost you want to start with the timing around 10* and slowly work it up while adding fuel to keep the AFR's and EGT's in there proper places. You do this until you get slight detination in 4th or 5th gear then you richen it up a little more. If it is still there then you back the timing off a hair. The dyno is where you want to fine tune the timing as it will see the torque start to drop off as the timing advances reach there limits before detination starts getting bad. You'll also see the EGT's start to bounce or shake when detination occurs. As long as you lift immediately upon detination onset your fine.

P.S.

You might want to go to the Dyno and watch so you can scream at em if you hear or see something they don't. Hope it all goes well for you this time around!

adjust a/f to the correct target afr then play with timing. if you detect knock adding fuel to a knocking engine is the improper way to tune an engine. if your engine has wrong. changing timing will greatly effect your egt's but changing timing will not change your a/f ratio so adding fuel will only make the car run richer which will result in a loss of power and drivability. if your timing is causing your engine to knock adding fuel will turn your car into a ticking time bomb, it will not fix the fact that you are running more/less timing than you should.

if you are hearing knock, you are way past where you should be with timing (considering your ve table is correct), adding fuel is not the correct way to fix this issue as you will jack up your afr cuz the amount of air in the cylinder is not changed.

well, i just realized our input doesnt really matter cuz jarid is not the one doing the tuning. corksport is doing the tuning. im going to ask my instructor if they are certified tuners or guess/trial and error tuners. imo, unless properly certified for high performance tuning i would not let anyone touch my car.

i spoke with my instructor and he told me that if an engine is built wrong it will likely blow up before it is broken in. if it is a tuning error, it will blow up on the dyno or shortly after. if it blows up after break in period and a while after tuning, it is more than likely the inherent weaknesses of a particular engine or just simply driving the hell out of it will break any engine with time properly built and tuned or not.

Ummm....timing GREATLY effects the afr's.

If your increasing timing on a suboptimal timing map the afrs will lean and knock...this is why I said add fuel. Once the timing map reaches the fuel/engine knock limits then yes it won't do any good to add more fuel, which is why I said to back the timing off if adding more fuel doesn't silence it.

Target afrs are only good on an ecu that will calibrate itself based off of a wide band input in which it will add fuel as you advance timing towards the engines optimal timing map.

EGTs do very between different engines but they all share something in common....EGTs rapidly raise, spike, waver as the engine starts to detinate. You'll actually see the egts peak and then start to drop before it leans out to far.

I'm not an amature tuner and have pushed engines to points many experianced tuners claim not doable on pump gas. I didn't do it for short bursts either. My test engine went 10,000miles of daily driving at 24-26psi on a Garrett GT3076R turbo w/ stock heat range plugs before finally snapping the #1 rod just below the wrist pin from cyclic fatigue (was using stock B6T bottom end with SMALL B6 rods). The current engine is nearly bullet proof.

As far as hearing detination being to late...so what is it that knock sensors do You do have to have a keen ear for it and react quickly...this is what the EGT and AFR gauges are there for....knock sensors can be decieving if not properly adjusted to the specific harmonics of the engine it is in.