GaryK,

I appreciate your comments as well as Max's. I don't like to see people fight but at least you know each of you feel strongly about what you have chosen to do.

Back On topic: You are correct we really don't know for sure that fuel delivery or cooling issues may be another factor in detonation with our kits. (We know timing is for sure) However if you look at many other kits, they offer: upgraded injectors, pumps, upgraded oil pans etc. I can't help but think they do this for a reason. There is also the fear that one of the injectors/pump may fail early while running at higher output levels. Do we know how long they or the pump will last? Granted I am playing the devils advocate. Maybe they will work fine indefintely however, they may not. It is my opinion that an upgraded pump, with injectors is superior than what we have. Is it necessary, we don't know yet. Should we all have oil coolers or upgraded oil pans? We don't know yet but it has been recomended by JIC and several others I have spoken with. I personally will be having a tranny cooler installed once I have the valve body upgraded and the torque conertor installed. Is it necessary, again we don't know. What we do know is it wont hurt.

For those that are going with the ECU flash route with injectors and pump, I think they are in better shape than those of us with simply the fmu and j&S option. (Although much more expensive) I feel this way becuase the chances for timing and fuel delivery(more so fuel delivery) issues will be less likely to occur.

Though I agree the J&S option is more accurate and effective. I don't competely agree that it is necessary. Looking at how well most of the procharged Z's have dealt with the timing issue... Is it really required that we measure per chamber? I hate to repeat myself but we don't know yet. We have and will continue to play the guessing game for several months to come. I take my hat off to people like you and Max who try new things and give your logic and experience behind them.

 

Oil coolers will definitely improve ones odds against detonation; or even one of those oil pans optimized with cooling fins and increased oil storage.

I am definitely, adding the oil cooler, by next summer.

Anything that can keep the combustion chambers sufficiently cooler will help.

As, for the J & S retard control, the packaging itself gives one a sense of quality; will see if that translates to the real world functions.

Will have the PE injectors, FPR & oil pump installed next week; I will know how well it'll work without the procharger FMU.

G

 

So, the ATI Pro-Charger won't work stand alone? I just want to run 6-7 psi with the computer mod they provide with the kit. Will this not be a reliable set up? The only other modification I plan on doing is the Stillen exhaust system. Please advise.

James

 

Not reliably......its blown a few engines here and there.......you have 2 options for a reliable set-up.......ECM reflash with bigger injectors, or the J & S timing control box

 

Assuming its like previosu units we have used, its adjustable for sensitivity (iei what kind of knock even tit takes to induce retard), and is also adjustable for the amount of retard it can provide.

 

In my simple mind the only things you need is to make sure there is enough fuel and no knock. (+ other things)

So from this thread I get the assumption that the standard injectors don't flow enough for the HP attainded. Now if I remember correctly 440cc injectors are good up to 350HP I *think*. So in this case you would need 380/440 and say a 500HP bosch fuel pump. In regards to timing the Xede can do static timing ie: Timing is hard coded and not dynamic as the J&S unit which detects and then retards.

With the Xede u would not need a SAFC. Now to be on even safer side why not use water injection or at least a water spray kit for the IC to drop the intake charge to prevent detonation? ie: The aqua mist products as used on rally cars for water injection

What I don't understand also is everyone states the SC kits are ***** with the current engine failures. But FI and SC both compress air so will have the same problems with turbos or SC's

Maybe it is me and happy to make 15-20 less HP then another Z owner. Most guys drive their cars for fun and not slips. If you want slips then rebuild your motor and do it right. A bolt on SC or FI is for *fun*. Ah well maybe I getting to old.

PS: I do think the water injection is a possible preventative though

 

Wow- a long thread-
i thought i'd just add this so people can understand how the ECU works--

The ECU DOES NOT run fully in close loop. It runs close loop under low rpm usually under 3k-4k at light load. Anytime there is heavy load, the ECU goes open loop and will ignore any and all o2 readings and go directly off what the MAF is measuring and what is program into the ECU. So however much volume of air the MAF measure, X amount of fuel will be injected out.

ECU mapping are in 3D. This means the map have different area to read depending on load and rpm. It doesn't need to have additional boost maps for boost application. However, it will read the same area of the table wheather it's turbo or n/a (this is same on turbo car ECU too). This is why we can lower timing for boost level. Because once you go WOT, it will read a certain spot in the map, if we change that, the ECU will read the new data in that area. Also there are 3 maps for the ECU to select the 'perfect' one depending on condition: temps, knock, low octane etc...

J&S system works great, when it's working. But it only works if it detects knocks. Why put your motor into a situation where it will knock/ping before something will work and THEN start retarting timing. The flashed ecu for SC/Turbo will retarded timing so it doesn't allow the motor to get into a knocking/pinging situation and saving your motor.


--Cheston

 

But we still don't know if the MAF can really read high enough to account for the volume when in a forced induciton application. I hope so, but nobody has been able to answer that for sure. That's why I will soon be logging my MAF output just to see what its doing at my current power level.

And you are wrong about the J&S. It serves two primary functions, one of which you mentioned. However, it also retards timing based on boost pressure, and the unit is adjustable for retard rate and starting point. When set up properly, the J&S WILL keep the motor out of a knock condition unless something beyond the control of the engine management happens.