Knock Sensor Light

rottenronnie

rottenronnie

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Has anyone found anything that will let you know when the knock sensors are being activated?
Other than the usual: Marbles in the engine, missing chunks of pistons, etc.

I've often thought of setting up some kind of a small light that could be wired into the cab.

I can't imagine it being too tricky but I've never researched it (yet).
 
Post your progress up
 
Will do Shorty.

I have to amplify the signal coming from the knock sensor to be able to activate a light or two as it is too weak to light even an LED right off of the sensor itself.

And, this has to be done in such a way that it won't "pull" from the signal heading to the ECU.

I'm looking forward to it working properly as things progress.
 
It's pretty noisy at W.O.T. at 190 km/hr (118 mph) at the top-end of a 1/4 mile pass, so a light of some kind is best.
 
Psycho1122 said:
I'd like to call it a "Piston Damage Light" :D

;)

Cheers!
Click to expand...

The old BB Mopar Combustion-Chambers (and particularly the 426 Hemi) needed a LOT of initial advance to produce good torque. Typically when they would produce light-ping under abnormal grunt conditions, they would make really good power at that particular altitude.

2 degrees of timing (either up or down) made an enormous difference in power production on those older engines. BB Fords didn't seem to care.

The original Hemis' had great volumetric-efficiency but poor combustion-efficiency. As there was no mechanical squish/quench going on, the plugs took a real shit-kickin'. I used to change plugs in my old 426 Hemi every 1500 miles.

Rising above the 10.25:1 compression ratio on the street-hemi was dangerous at best, even with decent fuel.

The 12.5:1 Race Hemis weren't long for this world. You can only do so much with piston top design to try to encourage Combustion Chamber cooling without mechanical Squish/Quench.

Sport bikes with true hemi chambers make it easy to light-off the mix and because they rev into oblivion, they don't really have time to have flame-front abnormalities (detonation).

Although the modern Viper engines Gen III Viper (OEM or Striker-headed) don't require high initial advance, there is (like with any other engine) a sweet-spot. With adjustable rockers I can play around with cam "timing" and favor either low OR high rpm power production through valve lash. Changing the valve lash with my current 11:1 pump-gas build keeps the knock-sensors VERY busy indeed as it makes the cam considerably smaller and builds cylinder pressure early (as the intake closes earlier).

IF I had a modern 8-speed in our trucks, it wouldn't be a concern to operate with timing on the fringe.
But I don't, and the 2-3 and particularly the 3-4 shifts put considerable load on the engine. That's why I had Chris Jensen wind out the shifts as far as possible through tuning. The 3-4 shift at 200 km/hr is an absolute treat!

I'm actually surprised there is time during a 1000 rpm WOT kickdown (while in 3rd or even Overdrive) to actually kickdown into 1st gear then complete a solid 1-2 shift without bouncing off the hard-limiter. I think I'm maxed out here. If I added another 2 or 3 hundred horsepower, I doubt the 48 RE could keep up. And no, I DO NOT WANT A 6-SPEED. :)

As I can't hear an engine ping anymore, I should be able to see it ping!

More Sunday-Afternoon ramblings...
 
Wouldn’t it just be possible to enrich the fuel curve richer at the higher rpm ranges on a tune ,,, add water injection to help cool the mixture a touch .. add a cool can to the fuel line to help keep the fuel cooler ..and something to lower the intake air temps for a more dense mixture entering the intake and combustion chamber .. with the benefits of creating more power and reducing the ping,knock and chances of detonation ...
 
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VIPR PWR said:
Wouldn’t it just be possible to enrich the fuel curve richer at the higher rpm ranges on a tune ,,, add water injection to help cool the mixture a touch .. add a cool can to the fuel line to help keep the fuel cooler ..and something to lower the intake air temps for a more dense mixture entering the intake and combustion chamber .. with the benefits of creating more power and reducing the ping,knock and chances of detonation ...
Click to expand...
Any and/or all of the things you mentioned will work.
As far as a rich(er) fuel mixture goes, that will COOL ANY PISTON engine, including Top Fuel.
That's how Mopar did it on the Gen 3s (as they were in the 10s A/F), with the stock tunes as many are aware. They were understandably protecting their investment (and ours) .
I know guys have had success (and failure) with injection systems, be it methanol or water. Personally I'm scared of those small electric, el-cheapo' white-metal motors that are crimped together. I've seen both water injection and meth injection systems stick ON and because liquids don't compress in a cylinder, you know the rest.
I'm not having detonation issues with the 8.3L, and the light is just a safeguard when installing increasingly aggressive tunes or when I'm out on the road where some gas stations are filling their Premium tanks with something other than Premium or its very stale, or whatever.
On a race only engine sure, I might use some kind of cooling spray if I was having detonation issues, but not on a daily driver.
I run a lean wot air-fuel ratio (arguably the most dangerous) and always have bought into the lean best power philosophies.
All in the name of science!
 
rottenronnie said:
Any and/or all of the things you mentioned will work.
As far as a rich(er) fuel mixture goes, that will COOL ANY PISTON engine, including Top Fuel.
That's how Mopar did it on the Gen 3s (as they were in the 10s A/F), with the stock tunes as many are aware. They were understandably protecting their investment (and ours) .
I know guys have had success (and failure) with injection systems, be it methanol or water. Personally I'm scared of those small electric, el-cheapo' white-metal motors that are crimped together. I've seen both water injection and meth injection systems stick ON and because liquids don't compress in a cylinder, you know the rest.
I'm not having detonation issues with the 8.3L, and the light is just a safeguard when installing increasingly aggressive tunes or when I'm out on the road where some gas stations are filling their Premium tanks with something other than Premium or its very stale, or whatever.
On a race only engine sure, I might use some kind of cooling spray if I was having detonation issues, but not on a daily driver.
I run a lean wot air-fuel ratio (arguably the most dangerous) and always have bought into the lean best power philosophies.
All in the name of science!
Click to expand...
Lol all in the name of science ..can get expensive , trial and error , you know what I mean .. I’ve heard the same stories about water/methanol injections since I was a little rat racer turd in the old days .. never tried it either . Didn’t feel I needed to .. tuned by vacuum back in those days .. I did use a cool can ( MOROSO) can’t really say it did anything ,, but regular ice instead of dry ice might have been needed ..
for a street driver you are right , water injection it’s not needed ,, race only would be its use ..
lean is king and yes dangerous the factory tunes are set extremely rich without a doubt ..
 
Your light idea is a good one imo ,,, better to know what’s going on than not no matter what it is ..
 
I’m not sure how many remember Marty .. the guy that made the first tune for the 10s for the SCT when it first came out .. he did a group buy on here ... I bought one then with 3 tunes he offered . I met him at a local gtg and had him run through his tune since my idle was a few hundred rpm Lower than it should be .. I asked him about the fuel curve adjustments in his tunes ... he told me he didn’t do fuel curve adjustments on them ... So I’m not sure how many tuners out of the box adjust fuel curves to lean out the factory rich mixture ... My guess is non of them do .. unless you actually take it to them or Dyno tune it ...
 
Yes, I tried an aluminum Moroso cool can back in the day (with regular ice as well) and also, can't say it did anything.
I told my cousin the coil inside was to accelerate the fuel before it hit the carburetor and made it ram-fuel to go with the ram-air. He just nodded and stared at it .

The light certainly isn't an original idea but I do like trying this and that.
And yes, science can get expensive but we will likely remember the failures when they have to be paid for !
 
rottenronnie said:
Yes, I tried an aluminum Moroso cool can back in the day (with regular ice as well) and also, can't say it did anything.
I told my cousin the coil inside was to accelerate the fuel before it hit the carburetor and made it ram-fuel to go with the ram-air. He just nodded and stared at it .

The light certainly isn't an original idea but I do like trying this and that.
And yes, science can get expensive but we will likely remember the failures when they have to be paid for !
Click to expand...

Lol gullibility testing people can be amusing ,, I do it to grandkids all the time .. love the reactions lol ..
 
Yes, I do remember Marty and I also tried a few of his tunes.
Chris Jensen definitely works on fuel trims and we've had him up in Calgary a few times for tuning sessions. I believe he is one of the very best. We don't agree on everything but, particularly with vehicles, that's not unusual.
We'd do some dyno pulls with wide-bands and then go out on the road and perform various driving loops. I'm not a peak horsepower guy but he left me a couple of agressive tunes that shut off the knock sensors (for use with Torco). I'm still using 4 hi-flows so I haven't been able to try race fuel and don't think it's needed; nor do I consider my truck to be a "race truck". When I bought it new it ran a 15.3 at a 5700 foot DA and, well, now it doesn't. :)
I do know in a lighter and lower vehicle it would drop from its current 11.88 pretty quickly.
This stuff is interesting and fun.
 
I have a 2002 dodge Dakota work truck .. thought about making it Look like a 10 .. hood , panels etc ... sort of a baby srt10 lol. Could you imagine putting the 10 motor and drive Tran into it .. smaller and lighter with the same visual look ... lol. .. that just might be scary sick ..lol
 
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