Australian Belly Tank

[Dr Goggles]

Hi All,
we had a stock knock sensor in the motor this year, The Colonel thinks it may have been retarding our ignition and thus been responsible for the sudden loss of power we had at exactly the same speed two days running....does this tally with anyone's experience?

Any advice , anecdotes or smart-axxery appreciated.

[El Wayno]

I have heard that knock sensors don't like some things. Gear drives are one and big cams are another. Gears click click back and forth and catch as a false signal. Big cam can do the same if the chain has a little slack. Don't know your combo so that's about it from this peanut gallery.

[Dr Goggles]

 Big cam, 52% overbalance, no suspension, a motor that is touching the frame ...............btw: the "Peanut Gallery?".....since when wasn't I in that?

[Reverend Hedgash]

Don't forget we had an untested chip too... maybe the programmer muffed the program at those revs....

rH+

[grumm441]

Don't forget we had an untested chip too... maybe the programmer muffed the program at those revs....

rH+

unlikely

[Nexxussian]

Any of the issues  I've heard of with stock knock sensors in modified engines have resulted from a nasty solid lifter cam (especially with larger lash, or no lash ramps) or a partially collapsed piston skirt.Not a complete list of the possibilities I'm sure.

[Geo]

I was reading on a street forum that some are unbolting the sensor, wrapping in foam and duct taping to the car body.  This keeps the sensor in the system but isolates from cam, headers, etc.  I would think running on a rough surface may set one off.  However if you have this happen at the same RPM IT'S ENGINE.

Geo

[Stainless1]

Are you sure you got retard or did it just nose over?  another comment from the PNut Gallery....

PNut Galleries are like cliques.... if you think there is one, then you are not in it....

[grumm441]

Are you sure you got retard or did it just nose over?  another comment from the PNut Gallery....

PNut Galleries are like cliques.... if you think there is one, then you are not in it....

It's hard to say if we got retard or not, but that's what the knock sensor is alleged to do. As I wasn't driving it , and its not been on a dyno , I'm guessing. And this is one of the things that can be problematic. Other options could be injector duty cycle, lifter pump up and valve bounce.
I haven't pulled any piston out of the sump, and the motor uses a roller cam.
G

[Milwaukee Midget]

I like Geoff's idea, and I seem to recall the Doc saying you had access to a dyno.  Might be worth an afternoon - optimize what you have, baseline the electronics and you'll have a starting point for the new cam, heads and rockers, and determine if it's the sensor.

You've got to burn up that leftover fuel in the tank, anyway, right?

And the Rev can re-learn the shift pattern.

PEEEEE NUTS - GIT CHORE PEEEEE NUTS

[grumm441]

This would solve the shift problem and speed it up
however it may blow the budget
http://www.renagate.com/info.htm
G

[Dr Goggles]

This would solve the shift problem and speed it up
however it may blow the budget
http://www.renagate.com/info.htm
G

by the time we got that to fit we would have had to "destroy the town to save the town".....
it would be simpler and cheaper to teach someone how to shift, we're already half way there....

we won't be doing anything with this years motor before the build Chris, it is , to quote Freddy King "All Tore Down"....


geez that's a great song..........

[wobblywalrus]

Usually knock is an issue during lower speeds with heavier loads.  Most of the time, at real high rpm the piston speed and flame propagation speed are more in sync and knock due to improper burn is not a problem.

Keep in mind that this is another peenut gallery opinion.

[SPARKY]

I read that GM had to do "stuff" with knock sensors on some of their Lemans stuff.

[Dr Goggles]

I asked the guy who did the chip( chips , peanuts....where's my fizzy drink?) and he said no it wasn't turned off but it could be....now, I like Geo's suggestion....simple and effective. Going to slightly higher flow injectors will allow us to rule them out too,.....the word is the stock injectors will support 250HP...but that, like the rumour I just heard about the Reverend could be nothing but idle gossip.