I would really appreciate it if someone could break out the differences between the years for the knock sensors on TPI and LT1 knock sensors and what the differences are.

The reason for this is that I currently have my knock sensor turned off in the custom chip that Fast Chips made for me (88 406 TPI setup). I would like to turn it back on when I start burning chips for myself as I do think it would be a valuable tuning aid.

However, I know that Formula5 has had some problems with getting his knock sensor to work. I have a flat tappet cam in my externally balanced 406...

I believe that someone mentioned that I could potentially use 93 SD LT1 knock sensor as an option...Why?

TIA,

BTW...I just got my Mattei cable and it looks like a great deal. I got the $70 kit and there are detailed instructions and all the parts I need plus a cigarette lighter cable/plug and he threw in a 10K ohm resistor in case I have a MAF...which I do. I know the extra parts aren't a big cost, but it is nice to get a complete kit. Sometimes you never know what you will get via the Net

 

BTW, I have searched the archives and couldn't find what I was looking for.

Someone has to know...

TIA again,

 

OK...this doesn't have to be in depth...just SOME differences

Since I know nothing about these...there has to be more people with more knowledge

 

My knowlege of knock sensors ends at the following:

OBD I sensors (1994 and older) have a 3900 Ohm resistance to ground.

OBD II sensors have roughly 10X that much resistance.

THerefore, I would think that the knock module and/or the ESC module that look at this sensor would have to be totally different.

There are differences between the 305 TPI, 350 TPI and LT-1 motors (different part numbers) but I'll be damned if I know what is actually different about them. They all look physically almost identical.

I would think that they would be "tuned" as far as being more sensitive to different frequencies and how much voltage they put out (sensitivity). But that's a guess.

 

Thanks Damon...for starting the trickle of info...

How about people running knock sensors with the flat tappet vs. roller? Or how about internally vs. externally balanced engines?

If I can't get more detailed specs, then the next step is experience...

Thanks!

 

Actually, and this is posted incorrectly, (I think), quite often, the '86-'89 knock sensor for a 165 MAF ECM that uses the ESC box in the engine compartment is 100k ohms and sells for about $25.00 (Wells brand) and the knock sensor for the '90-'92 730 SD ECM that has the ESC circuit built on the MEMCAL measures 3900 ohms and sells for about $45 (Wells also).

Autozone will get this wrong about 9 times out of 10! They list a AC-Delco for the '90-'92's but don't sell it, (here anyway) so they sell people (tried to sell me one) a Wells for the '86-'89. They crossed referenced the AC-Delco number and had the correct sensor in stock. Their computers just didn't show it correctly. I wonder how many folks that's screwed up!

The visual difference in the Wells knock sensors for the F-Body cars in the '86-'89 has a white top and measures 100k ohms and the '90-'92 has a black top and measures 3900 ohms.

The ohms can be measured before or after installation by testing from the single pin lead to the body of the sensor.

As far as the difference from 305 to a 350... I don't have a clue.
Same on the 93 SD LT1 knock sensor... I don't know.

Now, if all this turns out to be incorrect it'll at least explain why I don't think my NEW knock sensor is sensitive enough! It could be my PROM that I'm working on. I've read about people wanting to make them LESS sensitive, (wrap teflon tape on the threads, etc.)

Hope this helps!