I'm running a solid roller cam and was told that I would not be able to tune the timing via a knock sensor. Do any of you have any knowlegde in this area.

If I can't tune with the knock sensor..........what's the best way to do it?

 

Hay Lil Qik....To tune with the knock sensor is pretty easy. You are starting with a timing map of some degree I take it. You drive the car and moniter the timing map. Drive at different load ranges and look for the knock sensor to retard the timing. If the timing is being retared at a given load then you need to back out a couple of degrees timing. On the other aspect if there is no retard add timing until you get the knock sensor to pick up detonation and then back out 2 degrees of timing or until it does not retard the timing. At that point you will have the max timing you can run without detonation. Do this over the entire timing map at all load ranges.

If you are not able to use the knock sensor due to a solid roller, header noise ie: internal engine noise causing premature timing retard then you must look at you build up. Iron or aluminum heads, compression ratio, cam profile, cooling ect. to determin the amount of timing your engine will take without detonating.

The latter was my case with a 406 SBC. I run 34 degrees of total timing and at WOT it comes in at about 3000rpm. Good luck & hope this may have given a little insight.

 

Yea, I had to edit my post...........I meant to say that I could not use the knock sensor. My motor is totally built, I'm just a little worried about toasting it while playing with the timing. 406...........did you get my message as far as getting together and comparing notes...............ok,ok,ok................I need help and I'm scared to screw up the twin turbo. Anyway thanks for the advice.

 

just be conservative on the timing.....i'm not using a knock sensor and neither is guido

just keep adding timing until you dont go faster at the track or dont make anymore power on the dyno

thats the easiest way

 

Appreciate the help guys.

 

Engines got along fine with out Knock Sensors for decades.

Start with looking around the net for pics of what detonation looks like when reading plugs.

Then start with a very conservative timing map and tune from there.

Having a WB helps.

The biggie to remember is running the least amount of timing consistant with best performance. There's a huge difference between that and max timing possible.

 

Hey 406-Z,

I'm doing the same thing. How many knock retards on my scan are acceptable. Obviously you expect a few, but within the range of easy to slighly aggressive driving how many knock retard incidences would I want to see in perhaps a six mile drive (three miles up the road to warm it up-- turn around get on it-- coast back the driveway).

Thanks in advance for info-- I've sure been getting allot of "blank stares" when I ask this question.

Kendall