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Jeep Street and Performance Do you like to go fast in your Jeep?

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  #1  
Old October 23rd, 2011, 10:13
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Talyn Talyn is offline
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2 x cps = +6* timing

This is just a cheap and easy way to add 6* to the base timing. I had a spare know good CPS and a bad CPS. On the good CPS I redrilled the locating hole on the passenger side mount ~.5" in and then cut off the excess. I then cut off one side of the mount of the bad CPS. That was drilled and tapped for the bolts. The driver's side mount of the good CPS was marked and drilled. The cut off part was mounted to the good CPS using screws which go into the new threaded holes on the mount as well as nuts to lock them in. I used a washer to take up the space between the transmission and the offset mount.

This moved the CPS about 1/2" and added about 6* of base timing. I used a dial back style timing light and checked the timing before and after the modification. Its a bit ulgy and I could probably finished it a bit better but it works. I placed the CPS as far as it would go toward the passenger side without having to modify the bell housing.

It seems to have a bit more pickup at mid range and I haven't noticed any pinging yet. If it does I can dial it back through the AEM FIC.

Back side:


Front side:


Installed:
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  #2  
Old October 23rd, 2011, 10:38
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Re: 2 x cps = +6* timing

Awesome! I've thought about doing the same thing on our rig. It'd be nice to use the 91 octane more effectively when out of boost.
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  #3  
Old October 23rd, 2011, 14:41
eflores eflores is offline
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Re: 2 x cps = +6* timing

They actually made one from the factory for use on renix models...I run them on all mine
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Old October 23rd, 2011, 14:53
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Re: 2 x cps = +6* timing

I know, but mine isn't a renix.
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Old October 23rd, 2011, 15:13
eflores eflores is offline
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Re: 2 x cps = +6* timing

Well I figured that much just throwing the info out there
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Old October 23rd, 2011, 15:31
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Re: 2 x cps = +6* timing

my 4.6 can only run 91, would 6* of timing help it lower the octain needed?
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Old October 23rd, 2011, 16:00
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Re: 2 x cps = +6* timing

Quote:
Originally Posted by eflores View Post
Well I figured that much just throwing the info out there
Going off the pictures on Rockauto I don't think it advances it that much.
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Originally Posted by userbmx1315 View Post
my 4.6 can only run 91, would 6* of timing help it lower the octain needed?
No, it would make your engine ping more. You might be able to go the other way with it though, towards the driver's side to decrease timing. However, since you currently need 91 octane, you may be able to advance it w/o ping.
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Old October 25th, 2011, 21:33
Super mud Super mud is offline
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Re: 2 x cps = +6* timing

I've done this on my Renix though I actually just put the CPS in the vice loosley and tapped with a hammer end to slide the magnet along the mount though placed a bolt in the end I was hitting to prevent smashing the bolt hole. I've seen it other places on the forum too.

Though I'm wondering if I got too much timing cause every once in a while I get a backfire (through the intake) with sudden throttle input and I've heard timing can cause backfire or afterfire (out exaust) depending on which way it's gone. Then I wonder if I run 91 with the advance if it will improve and smooth things out.
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Old October 26th, 2011, 07:18
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Re: 2 x cps = +6* timing

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Originally Posted by Super mud View Post
put the CPS in the vice loosley and tapped with a hammer end to slide the magnet along the mount
I tried that on the faulty sensor first. That didn't work out so well.
Quote:
Though I'm wondering if I got too much timing cause every once in a while I get a backfire (through the intake) with sudden throttle input and I've heard timing can cause backfire or afterfire (out exaust) depending on which way it's gone. Then I wonder if I run 91 with the advance if it will improve and smooth things out.
Adjusting the timing that little wouldn't cause that issue. I think you have something else going on.
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Old October 26th, 2011, 14:11
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Re: 2 x cps = +6* timing

Quote:
Originally Posted by Super mud View Post
I've done this on my Renix though I actually just put the CPS in the vice loosley and tapped with a hammer end to slide the magnet along the mount though placed a bolt in the end I was hitting to prevent smashing the bolt hole. I've seen it other places on the forum too.

Though I'm wondering if I got too much timing cause every once in a while I get a backfire (through the intake) with sudden throttle input and I've heard timing can cause backfire or afterfire (out exaust) depending on which way it's gone. Then I wonder if I run 91 with the advance if it will improve and smooth things out.
I've done that at least 10 times with excellent results. But, my friend tried it on his and the molded plastic came all apart.
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  #11  
Old October 26th, 2011, 14:54
Shorty Shorty is offline
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Re: 2 x cps = +6* timing

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Originally Posted by Talyn View Post
This is just a cheap and easy way to add 6* to the base timing.
have you noticed any slower cranking or harder/easier starts? I've always felt like mine is more retarded than it needs to be, but I've been hesitant to futz with it as of now.
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Old October 26th, 2011, 15:39
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Re: 2 x cps = +6* timing

No difference in cranking at all. Just futz with it.

Shorty, what year is your Jeep?
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  #13  
Old October 26th, 2011, 16:44
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Re: 2 x cps = +6* timing

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Originally Posted by cruiser54 View Post
No difference in cranking at all. Just futz with it.
x2 Cranking is unchanged. I was cautioned that when messing with timing it could possibly making cranking harder and if you go to far it would bust the nose on the starter. I don't think 6* is enough to do that.

I definitely feel a nice mid range increase since driving it after the mod.
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Old October 26th, 2011, 18:14
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Re: 2 x cps = +6* timing

Everything to gain, nothing to lose.
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  #15  
Old October 27th, 2011, 02:21
Shorty Shorty is offline
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Re: 2 x cps = +6* timing

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Originally Posted by cruiser54 View Post
No difference in cranking at all. Just futz with it.

Shorty, what year is your Jeep?
an '88 and a '94. The '88 is the one I've been wanting to futz with for the most part.
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