How would you tell if its preignition, pinging, or detonation or are those all the same thing? I have this kind of metallic rattle when going into boost which has me staying away from it. I bumped down the timing about 3 degrees around the whole map and it has not changed. The only different thing i've done was put 89 instead of 93 because the station was out.

 

The difference in octane could be it, BUT!, this sort of thing also happens when you do not have the timing zero'd in correctly, or you've got your trailing plugs (or all plugs) wired up wrong, or just your trailing wires are backwards.

What ECU?

 

e6k. Im sure the trailings are not backwards unless it just fires them different. Or that could be the cas is in backwards right? I'll swap them and check later today, but when i timed it first they were sparking right at the marks on the pulley. I did have to put the trigger angle to 101 for them to line up though which seemed kind of high to some others i've seen.

 

checked the timings ok for leading and trailing. Added some octane booster, but its still there, but more of a squak or squal now which probably might be something besides the motor.

 

+1. Bet the timing isn't zero'd properly. Bet it's firing ahead atleast 10*+.

Was this motor apart? Did it have any switcheroo on the front hub/pulley pair?

B

 

Just rebuilt it. S4tii bridgeport motor with n/a rotors. I thought the pulley might be the wrong one. I might just have to find tdc and then make new marks.

 

Heh, heh, heh.

How to find TDC with a 2nd gen motor:

- Purchase Racing Beat or other aftermarket, machined pulley/hub piece w/ known good timing marks
- Remove existing pulley and hub
- Insert New; rotate to TDC
- Remove new; re-insert old, chisel a mark on pulley for new TDC mark

This is a bad enough problem on 2nd gens that I carry a known-good pulley/hub combination with me in my bag when I go out of town. It's an annoying pain in the rear, but a critical enough thing to warrant it's necessity at times.

Front hubs and pulleys are *matched pairs* that should not ever be mixed up!!!

B

 

Its wierd though. I found that website were you look through the rear plug holes and mark the pully where they are both between and thats were my pulley is which would mean that it is a tdc and the cas is right on the mark. The base is turned to the far clockwise position but there all lined up.

 

If you want to trust something visual like that for setting up TDC and hoping you've got precise exactness, don't let me stop you.

B

 

I forgot to mention that I had to use 3 for the tooth offset instead of 11 which probably might be why my stock tach is 2x the rpm. It just doesn't start with 11 but the tach doesn't bounce as high when on 11 compared to 3.

 

If the tach is twice what it should be, it means the toggle lead for your trailing ignitor pack isn't wired up right, meaning it's firing the T1 coil twice as much as it should and the T2 coil none at all. That may be what's causing your dink-dink-dink noise, come to think of it. Double-check the two wires going to the trail-pack.

The 3 and 11 tooth offset are a major calibration value relative to how the CAS is stabbed in with respect to the engine being at TDC -- remember the gear on the bottom of the CAS? Rotating it tooth at a time is the same thing as changing that Tooth Offset figure. Stock insertion method will necessitate an 11 value in that Ignition Setup page. Otherwise, if you follow HITman's preferred method, it requires 3.

B

 

Yea i got it in the stock way but on 3 because it wasn't sparking right. It would spark once and then stop even while still cranking. I'll check the wires again, but pretty sure there wired correctly.