Knock sensor

[OldMachinist]

I have a friend with a 66 GTO whose engine was damaged by detonation. I was riding in the car at the time and we couldn't hear anything as far as pinging goes to warn us. Does anyone know of a knock sensor with some kind of light or gauge that would give a person a warning in this application?

[Matt Cramer]

I haven't used one myself, but these guys have a very good reputation:

http://www.jandssafeguard.com/

[OldMachinist]

That looks like a very nice unit but I was hoping to find something a little cheaper and less elaborate. You never know when you will get a bad load of fuel and a warning light would allow you to compensate. I notice you can adjust the sensitivity and wonder how you would do that?

[dieselgeek]

I have bad luck with knock sensors and don't recommend them. Lots of people on the internet say "got one and it works great" but the fact is, how do you test and know it's working without significantly knocking or pinging the engine? Some say you can set them to where they barely do not go off at WOT, but having seen what happens to factory sensors (with exception of LS engines that seem to have great sensors and design) as soon as you add headers to the engine, makes me not trust it. You can spend days trying to get rid of knock that isn't really there, or you could have a sensor and display that never shows you knock while the ringlands and bearings are beat to crap... my thought is to tune carefully looking at the plugs, leave in a safety margin for crap gas, NEVER buy premium pump gas from a mom & pop place, and know that your tuneup is safe from knock.

[anotheridiot]

I just think knock sensor is a bad name for the device. Its is picking up frequencies one can barely hear, and going thru the computer to adjust timing and fuel at the computer. I dont know what the reason would be to have one, or what you would adjust.

I am considering doing a http://www.ebay.com/itm/250606974154...84.m1438.l2649 by adding an O2 sensor in the exhaust that would be something visual to see if the motor is running fat or lean to be able to make adjustments at the carb to keep the car in range where detonation wont start.

Anybody see my reasoning and think its a good idea?

[Dynoroom]

My advice would be the same as the Geeks above. I've run them on the dyno before and it's always on during any high power test it seems. You'd be chasing your tail using one driving.

[OldMachinist]

Thanks for the input. I think I'm going to end up with the car because of his divorce. It's all fresh and I don't want to spend a lot on it but I am planning an A/F meter for sure. It has headers and a hyd. roller and the lifters seem somewhat noisy so detecting actual spark knock would be hit or miss at best.

[Barry Donovan]

enough amperage brings a noise.

try going 110 amp alternator or something.
even a little tin can worships gm 90amp.

I blew an engine, same thing..no noise.

I recently found the alternator was being a pansy, it was on engine that blew. it used to make the noise, Amps just got weak I guess.

[TheSilverBuick]

I've abandoned my knock sensor dream :*( I still have one installed in my Buick 455, and I may wire it up some day on the MS3, but currently I'm pretty sure my valvetrain is to noisy to be useful. I'll probably re-think it after getting roller rockers and adjusting the valve lash.

[skullbucket]

If you have to add a Knock sensor on a manually timed car something is wrong and you need to find the problem and stop trying to mask it.

[OldMachinist]

My main concern is getting less than optimum fuel if I drive it very far from home. You never know where you have to get gas out in the boondocks. I might take it to Moab and its pretty desolate that direction.