Jeep Strokers

I have done some searching but am running out of time to before going to the shop tomorrow morning. I am getting some detonation issues (most likely) and wanted to know if anyone has experience adjusting the crankshaft position sensor to retard the timing? Money is tight at the moment, so i can't afford any of the custom programming available out there.

Is it as simple as opening the the bolt holes and sliding the sensor a bit until the knock is gone? I have an auto in an '01 Cherokee with 4.6 stroker that starts to knock under load once warmed up and above 1800 rpm. 500 miles into the break-in. I'm at 5.000 feet (Denver) and running premium fuel. Has anyone gone through this procedure and what was their experience. I'm still learning so please bare with me folks!

The valve train has been re-checked and re-tightened so we think we're narrowing it down to timing. Thanks again for any input you can give!

What is your build? Your Compression ratio and or quench must be really REALLY high if your pinging @ 5000ft with premium.

Your probably better off adjusting fuel with an adjustible FPR, or an adjustable MAP. Are you sure you dont have a bad injector or something? Is it on all cylinders or just one or two?

Being that he has a 2001 an adjustable fuel pressure regulator $ pump is like $400 from Hesco.

But we need more details. What is your build? Dynamic compression and static compression? What injectors are you running? What spark plugs?

You can modify the crank sensor a bit by opening up the holes. To retard you would move it toward the passenger side, to advance toward the driver side. I think you will only get like 4* either way without completely hacking up the sensor.

Well I had something come up and am finally back to the stroker. Its the simple. Stock cam, 677 pistons, 258 rods. Block wasn't decked, so yeah, the compression is real high. I have 26lb injectors, RC9YC plugs. It sounds like all cylinders. They are brand new injectors from FiveO motorsports. I'm going to try to to add some octane booster to see if that may help. We had a sniffer hooked up and it was a tad on the rich side, but everything else checked out. Even had a buddy hook it up to the fancy shop computer at the dealership and he said everything was inline. Am I just up a creek? Maybe a hotter cam?

Thanks all!

Maybe I should scrap the 677's. What would be the best pistons to use? There's a number folks mention, but for my set-up? Thanks!!

SilverXJ wrote:You can modify the crank sensor a bit by opening up the holes. To retard you would move it toward the passenger side, to advance toward the driver side. I think you will only get like 4* either way without completely hacking up the sensor.

I think you might have that backwards. I just purchased and installed the HA CPS, and its clocked towards the passenger side to advance the timing.

Yes, you are correct. I don't know what I was thinking.. maybe looking at the engine from the wrong view point in my head.. or I had been drinking.

Muad'Dib wrote:

SilverXJ wrote:You can modify the crank sensor a bit by opening up the holes. To retard you would move it toward the passenger side, to advance toward the driver side. I think you will only get like 4* either way without completely hacking up the sensor.

I think you might have that backwards. I just purchased and installed the HA CPS, and its clocked towards the passenger side to advance the timing.

What is the HA crank sensor you speak of ? I`d love to crank in a few more degrees of timing.

jsawduste wrote:

Muad'Dib wrote:

SilverXJ wrote:You can modify the crank sensor a bit by opening up the holes. To retard you would move it toward the passenger side, to advance toward the driver side. I think you will only get like 4* either way without completely hacking up the sensor.

I think you might have that backwards. I just purchased and installed the HA CPS, and its clocked towards the passenger side to advance the timing.

What is the HA crank sensor you speak of ? I`d love to crank in a few more degrees of timing.

I saw the above pic was from rockauto.com and they don't carry any parts with this pic for my TJ. I looked at the pic below and dremeled my CPS to match and it works great for me. I did have to cut the rubber shroud on the bell housing to get the adjusted CPS to fit.

I'm sure that the OP could use the logic I did and do the opposite to retard his timing.