Problems, problems, problems......
Pro
Joined: Oct 2001
Posts: 682
Likes: 23
From: loxahatchee fla
http://forum.grumpysperformance.com/...php?f=52&t=727
http://victorylibrary.com/mopar/cam-tech-c.htm
http://victorylibrary.com/mopar/cam-tech-c.htm
these might help, as will reading thru the linked and sub links posted earlier
Im not saying your cam being correctly or incorrectly indexed is your only problem, but with out a step by step systematic approach checking and eliminating each potential problem area from the discussion its rather pointless to jump around guessing and swapping parts randomly in the hope you hit on the answers
http://victorylibrary.com/mopar/cam-tech-c.htm
http://victorylibrary.com/mopar/cam-tech-c.htm
these might help, as will reading thru the linked and sub links posted earlier
Im not saying your cam being correctly or incorrectly indexed is your only problem, but with out a step by step systematic approach checking and eliminating each potential problem area from the discussion its rather pointless to jump around guessing and swapping parts randomly in the hope you hit on the answers
Last edited by grumpyvette; Oct 31, 2009 at 02:32 PM.
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
I think this is one of the best threads in a while. Athough I am sorry to see the op in a jamb, it does offer some great info.
Once the internet caught on, it has become a great source of info. Unfortunately, it makes every project sound somewhat easy. Cam swapping has never been a bolt in. Nor has any modification to an engine that changes it geometry.
As grumpy has discussed, proper cam phasing, verification of parts, spring pressures, spring set up, rocker arm and pushrod geometry etc, always require verification before the motor fires.
There is a good lesson here. I too, learned it the hard way.
Once the internet caught on, it has become a great source of info. Unfortunately, it makes every project sound somewhat easy. Cam swapping has never been a bolt in. Nor has any modification to an engine that changes it geometry.
As grumpy has discussed, proper cam phasing, verification of parts, spring pressures, spring set up, rocker arm and pushrod geometry etc, always require verification before the motor fires.
There is a good lesson here. I too, learned it the hard way.
Pro
Joined: Oct 2001
Posts: 682
Likes: 23
From: loxahatchee fla
the first step is verifying all the sensor outputs and making sure any adjustable factors like the TPS, O2 sensors, mat,heat sensors,etc. and timing and fuel pressure meet the aligned ranges,and potential problems like vacuum leaks, and the TIMING TAB INDICATING TDC are correct and reading all trouble codes , then move on to the mechanical problems, like adjusting the valves and verifying the cams indexed correctly, and the valve train geometry is correct.
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
Last edited by grumpyvette; Oct 31, 2009 at 04:02 PM.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I think this is one of the best threads in a while. Athough I am sorry to see the op in a jamb, it does offer some great info.
Once the internet caught on, it has become a great source of info. Unfortunately, it makes every project sound somewhat easy. Cam swapping has never been a bolt in. Nor has any modification to an engine that changes it geometry.
As grumpy has discussed, proper cam phasing, verification of parts, spring pressures, spring set up, rocker arm and pushrod geometry etc, always require verification before the motor fires.
There is a good lesson here. I too, learned it the hard way.
Once the internet caught on, it has become a great source of info. Unfortunately, it makes every project sound somewhat easy. Cam swapping has never been a bolt in. Nor has any modification to an engine that changes it geometry.
As grumpy has discussed, proper cam phasing, verification of parts, spring pressures, spring set up, rocker arm and pushrod geometry etc, always require verification before the motor fires.
There is a good lesson here. I too, learned it the hard way.
the first step is verifying all the sensor outputs and making sure any adjustable factors like the TPS, O2 sensors, heat sensors, and timing and fuel pressure meet the aligned ranges,and potential problems like vacuum leaks, and the TIMING TAB INDICATING TDC are correct and reading all trouble codes , then move on to the mechanical problems
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
Pro
Joined: Oct 2001
Posts: 682
Likes: 23
From: loxahatchee fla
http://forum.grumpysperformance.com/...it=+tabs#p1864
when you degree in a cam youll mark TDC on the damper and ideally add a timing tape (YES IM fully aware the LT1 has very limited room for timing tapes and you have the CPU control timing) but the marks are still useful for verifying the timing, and indexing the cam,
http://www.jegs.com/i/JEGS/555/51605/10002/-1
http://ep.yimg.com/ca/I/spideraccessories_2077_17686689
when you degree in a cam youll mark TDC on the damper and ideally add a timing tape (YES IM fully aware the LT1 has very limited room for timing tapes and you have the CPU control timing) but the marks are still useful for verifying the timing, and indexing the cam,
http://www.jegs.com/i/JEGS/555/51605/10002/-1
http://ep.yimg.com/ca/I/spideraccessories_2077_17686689
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
the first step is verifying all the sensor outputs and making sure any adjustable factors like the TPS, O2 sensors, mat,heat sensors,etc. and timing and fuel pressure meet the aligned ranges,and potential problems like vacuum leaks, and the TIMING TAB INDICATING TDC are correct and reading all trouble codes , then move on to the mechanical problems, like adjusting the valves and verifying the cams indexed correctly, and the valve train geometry is correct.
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
if you don,t own a factory shop manual, a vacuum gauge, timing light, V.O.M. meter and a few injector NOID LIGHTS, and a fuel pressure gauge you need to get those
The TPS is not adjustable unless you physically grind it out like and L98 engines. So, that is not adjustable.
Fuel pressure should be factory set at 43.5 psi with vacuum line off. To adjust it you need an aftermarket adjustable regulator. But, this tune was set for your injectors at factory psi of 43.5.
You injectors first test should be whether they are in good resistance, which is 14-16 Ohms, simple test. Put a Ohm meter on the two metal tabs on your injectors.
If you have a data-logger, vacuum and every other thing we need to see to determine problems will be shown. Your dyno operator already told you one significant one, in regards to BLMs being way off. And being sequential, and BLMs being off on one side, tells me allot of ways to go.
ANd there are no codes, no check engine lights either.
I am going with Bad Opti, or loose O2 sensor within the bung.
Steve
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Racer
Joined: Aug 2008
Posts: 457
Likes: 2
I had a similar problem with my car.It would drive pretty good at lower rpm's but if I stomped on it at higher rpm's it would cut out like I was hitting a rev limiter or something.I changed my ICM(ignition control module)and problem was fixed.Check your out if you have'nt already.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Pete, I haven't even cranked it back up since last Sat. I have a little home project going on that I have to finish first. It's taking up my carport/garage/woodworking shop. Another week or so of this project and I hope to get back into the garage part. Don't worry, I'll post the results here if I ever find them.........
I had an extra one lying around and tried it but no change. Other than a sluggish feeling when it hits 3rd I can't tell anything is the matter. No backfiring or skipping going on. It's looking like I'm probably going to have to degree the cam in. If for no other reason just to eliminate it as the problem or it fixes the problem, one or the other.
Another week or so of this project and I hope to get back into the garage part. Don't worry, I'll post the results here if I ever find them.........I had a similar problem with my car.It would drive pretty good at lower rpm's but if I stomped on it at higher rpm's it would cut out like I was hitting a rev limiter or something.I changed my ICM(ignition control module)and problem was fixed.Check your out if you have'nt already.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
LT4 knock module
I didn't change mine to an LT4 module.
I believe my tuner changed knock retard desensitizing so I didn't change the module. Does this get the same results as changing the module?
I read somewhere that this can reduce HP by 29 if the module isn't changed with regular sensitivity of the LT1 module when using 1.6 rr's with a cam.
I haven't started back on the car yet, just been reading. That can be good or bad sometimes.
I believe my tuner changed knock retard desensitizing so I didn't change the module. Does this get the same results as changing the module?
I read somewhere that this can reduce HP by 29 if the module isn't changed with regular sensitivity of the LT1 module when using 1.6 rr's with a cam.
I haven't started back on the car yet, just been reading. That can be good or bad sometimes.
Last edited by Weav's Vet; Nov 10, 2009 at 03:59 AM.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
I didn't change mine to an LT4 module.
I believe my tuner changed knock retard desensitizing so I didn't change the module. Does this get the same results as changing the module?
I read somewhere that this can reduce HP by 29 if the module isn't changed with regular sensitivity of the LT1 module when using 1.6 rr's with a cam.
I haven't started back on the car yet, just been reading. That can be good or bad sometimes.
I believe my tuner changed knock retard desensitizing so I didn't change the module. Does this get the same results as changing the module?
I read somewhere that this can reduce HP by 29 if the module isn't changed with regular sensitivity of the LT1 module when using 1.6 rr's with a cam.
I haven't started back on the car yet, just been reading. That can be good or bad sometimes.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
LT1s have no timing marks, and you only can check timing via datalogging. I am sure someone has gone down the path of putting an aftermarket damper, but even then timing is set electronically via programming.
The TPS is not adjustable unless you physically grind it out like and L98 engines. So, that is not adjustable.
Fuel pressure should be factory set at 43.5 psi with vacuum line off. To adjust it you need an aftermarket adjustable regulator. But, this tune was set for your injectors at factory psi of 43.5.
You injectors first test should be whether they are in good resistance, which is 14-16 Ohms, simple test. Put a Ohm meter on the two metal tabs on your injectors.
If you have a data-logger, vacuum and every other thing we need to see to determine problems will be shown. Your dyno operator already told you one significant one, in regards to BLMs being way off. And being sequential, and BLMs being off on one side, tells me allot of ways to go.
ANd there are no codes, no check engine lights either.
I am going with Bad Opti, or loose O2 sensor within the bung.
Steve
The TPS is not adjustable unless you physically grind it out like and L98 engines. So, that is not adjustable.
Fuel pressure should be factory set at 43.5 psi with vacuum line off. To adjust it you need an aftermarket adjustable regulator. But, this tune was set for your injectors at factory psi of 43.5.
You injectors first test should be whether they are in good resistance, which is 14-16 Ohms, simple test. Put a Ohm meter on the two metal tabs on your injectors.
If you have a data-logger, vacuum and every other thing we need to see to determine problems will be shown. Your dyno operator already told you one significant one, in regards to BLMs being way off. And being sequential, and BLMs being off on one side, tells me allot of ways to go.
ANd there are no codes, no check engine lights either.
I am going with Bad Opti, or loose O2 sensor within the bung.
Steve
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I have asked my tuner for the file but he is reluctant to let me have it. Just ask what I needed to know and he would tell me.
Examples of programming options:
- Powertrain retrofits into other chassis
- Transmission conversions (A4 to M6, A4 to Th350, Th400, etc.)
- Idle adjustment
- Adjusting for different size injectors
- Knock retard desensitizing
- Skip shift elimination (M6)
- Shift points/shift firmness/shift kit/different stall adjustments (A4)
- Rev limiter adjustment, disabling/adjustment of the speed limiter
- Ported heads/headers/exhaust/aftermarket camshaft tuning
- Fan turn on temperature adjustments
- Speedometer/Auto transmission shift point adjustments for different gear/tire size
- Premium gas power tuning
- Larger throttle body adjustments
- Larger/ported mass airflow sensor adjustments
- Different engine displacement adjustment
- Programming for supercharged applications, if you have access to wideband o2 readings and your own cable.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
uh......you may have put these is the wrong thread.....