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Discussion Starter #1
Who launches at 1800 RPM or above? Do you get timing pulled with the TC locked up?

I lose 8 degrees as soon as I nail it from a >1600RPM stall. Only allows me to get to 21 degrees in 1st starting out at 8 degrees at launch. 1st to 2nd and 3rd to 4th shifts drop to 16 degrees at shift and makes it to 22 degrees over 6K RPM.
So would a lower launch RPM allow me to start out with more timing and would it be quicker? Seems like the 60' would suffer but maybe I'm looking at this wrong.
 

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What is your A/F Ratio before and after shift?

What tends to happen is the throttle blade closes slightly during the shift which in turn causes the timing to drop and A/F Ratio to change.
 

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Discussion Starter #3
What is your A/F Ratio before and after shift?

What tends to happen is the throttle blade closes slightly during the shift which in turn causes the timing to drop and A/F Ratio to change.
They are rich as I was running 90% meth for the octane. Blue graph is the throttle pos sensor and no dips at shift. No fuel pulled either (pale green lower line is from my wb).
My tune pulls 5 degrees at shift 21 to 16 or 22 to 17 degrees. If I pull less than that, it is KNK city.
I looked at some 426 stroker logs and he launches around 1160 RPM and his timing drops from 19 to 16 at launch. I was launching at 18K to 22K and my timing is 8 degrees out of the hole. So am I at 8 degrees at launch because I have flashed the TC and ECU is pulling 8 degrees? Only thing I can figure.
Guess I'll try launching around 11K to 12K and see if my launch timing is in the teens. Then I'll compare my 60' times to some 2K launches and see which is the lesser evil.
First impression is launching harder is penalizing me where I thought it would help my 60' times.
 

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I've always heard that getting above 1500 or so would pull timing..which is why I normally launch from anything between idle and 1200. It worked well enough for my R/T to pull a 1.758 60' on the stock converter, and open 3.06 rear.
 

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Discussion Starter #6
I've always heard that getting above 1500 or so would pull timing..which is why I normally launch from anything between idle and 1200. It worked well enough for my R/T to pull a 1.758 60' on the stock converter, and open 3.06 rear.
That's a respectable 60' for sure. I cut 1.77 to 1.82 pretty consistently with the 26" DRs and 1.8 with the 28" DRs. Guess what has me thinking is when I hammer it from a high stall, I get good 60' times but have the timing penality. I'll try not stalling her up so high and see if that gets me through first gear quicker with more timing while not hurting my 60' times. Close to 300 passes and still learing/analizing this thing.
 

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On my R/T with a 3,200 rpm FTI converter, my best launches were always from flashing the converter from just above idle vs brake stalling to a higher rpm. Not sure what was going on with timing though as I didn't data log it.
 

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Who launches at 1800 RPM or above? Do you get timing pulled with the TC locked up?

I lose 8 degrees as soon as I nail it from a >1600RPM stall. Only allows me to get to 21 degrees in 1st starting out at 8 degrees at launch. 1st to 2nd and 3rd to 4th shifts drop to 16 degrees at shift and makes it to 22 degrees over 6K RPM.
So would a lower launch RPM allow me to start out with more timing and would it be quicker? Seems like the 60' would suffer but maybe I'm looking at this wrong.
Im one who climbes on the TC. I stage, and as as the lights come down Im ramped up to 3000 and the car dont move and it doesnt pull timing. Once wot on the green it stalls 4100 before it moves and dont pull any timing.
I sometimes get a 1 to 2 deg after the shift and rpm drops and the motor loads back up. Running 14deg timing and 104oct fuel and low AIT My race tune so timing tips in up fast
During the summer I had trouble and would pull 14deg st knk even on race fuel. Drove me nuts....
It was a mechanical knk,,, this will get ya, from the suspension !!!! Once fixed no more timing being pulled.
I didnt want to beleave it either.
What side are you having the knk, ? I log the voltage to the sensors and found mine was from the passenger side knk sensor. Log them and see if its both sensors hearing it or is it always one side or the other.
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Discussion Starter #9
KNK Sensor Voltage Measurement Advice Needed

So to log the knk sensor voltages, is there a pid for it or are you using the analog 1 & 2 inputs? 0 - 5V?
Any help woud be appreciated. I used to only look at my KNKs and change the % fuel (from the wb) and or timing to keep them at bay. Now I change the % meth to knock them out and keep my timing/fuel added. I noticed my actual timing taking a dump as I go from 2K to WOT. She holds 16 degrees stalled up at 2K but as soon as I hit WOT it pulls 8 degrees. After seeing a stroker leave the line at 13 degrees got me wondering... Seems like leaving at 8 degrees would be slower than a soft launch as the VVT and phaser isn't as quck at gaining timing.
I've always had a ghost ST KNK just as I go into third at 4400 RPM. Doesn't happen in 1st or 2nd and doesn't go away if I pull a degree in the mid range so maybe it is false (rattle or something).
 

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So to log the knk sensor voltages, is there a pid for it or are you using the analog 1 & 2 inputs? 0 - 5V?
Any help woud be appreciated. I used to only look at my KNKs and change the % fuel (from the wb) and or timing to keep them at bay. Now I change the % meth to knock them out and keep my timing/fuel added. I noticed my actual timing tak

ing a dump as I go from 2K to WOT. She holds 16 degrees stalled up at 2K but as soon as I hit WOT it pulls 8 degrees. After seeing a stroker leave the line at 13 degrees got me wondering... Seems like leaving at 8 degrees would be slower than a soft launch as the VVT and phaser isn't as quck at gaining timing.
I've always had a ghost ST KNK just as I go into third at 4400 RPM. Doesn't happen in 1st or 2nd and doesn't go away if I pull a degree in the mid range so maybe it is false (rattle or something).
O
Wow, I had that deal myself before I built the stroker. On the stock motor last run of the 2012yr I twisted out my first DSand buzzed the motor really bad. I then since had what you describe, what I did was bent 3 pushrods. Motor didn't run rough or even throw a code, but it pulled timing as i mashed it. Like u are. The pushrods are really cheap junk.
I'm thinking you got something mechanical making noise. Bent pushrod, broken spring. Stock springs are in buckets. When broke won't drop like without the bucket, but it will make noise. I'd almost bet pushrod. If it is, and u go to chrome Molly, I'd suggest going with the longer pushrods. Keeps the hemi tick away. Think there like 10th longer. Mine are ford pushrods part number.
You should have knk sensor voltage pid. I can't remember if labeled right or left, and I may have used the snap on software when I was on the rollers to see right and left. I know we can see knk voltage just dont remember if right and left was labeled.
By doing so will let you know what side trouble is on.
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Discussion Starter #11
O
Wow, I had that deal myself before I built the stroker. On the stock motor last run of the 2012yr I twisted out my first DSand buzzed the motor really bad. I then since had what you describe, what I did was bent 3 pushrods. Motor didn't run rough or even throw a code, but it pulled timing as i mashed it. Like u are. The pushrods are really cheap junk.
I'm thinking you got something mechanical making noise. Bent pushrod, broken spring. Stock springs are in buckets. When broke won't drop like without the bucket, but it will make noise. I'd almost bet pushrod. If it is, and u go to chrome Molly, I'd suggest going with the longer pushrods. Keeps the hemi tick away. Think there like 10th longer. Mine are ford pushrods part number.
You should have knk sensor voltage pid. I can't remember if labeled right or left, and I may have used the snap on software when I was on the rollers to see right and left. I know we can see knk voltage just dont remember if right and left was labeled.
By doing so will let you know what side trouble is on.
Flattop
Wouldn't surprise me if some of the PRs were a little bent with as many passes as I have done with this engine. No more audio ticking than the day I got it but it doesn't take much for these sensors to pick up stuff.
I'll search for the PID or I thought about hooking a voltmeter up at the track in the Hold mode to see which sensor has voltage.
So roll the rods on a flat surface plate and look for wobble? Or measure actual lenght? Used to have a 351 Cleveland that would bend rods everytime the vlaves floated.
Thanks for the pointers.
 

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welcome sir. yes volt meter on hold will do, then go out and lean on it. I couldnt belive how well mine ran with them bent and even pulling timing. I just kept seeing it in my logs and it fliped me out.
Good Luck
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