Results 1 to 10 of 10

Thread: 95 LT1 24x CONVERSION CRANK NO START FUELED PLUG DRY

  1. #1
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Lake of Como - Italy
    Posts
    219

    Unhappy 95 LT1 24x CONVERSION CRANK NO START FUELED PLUG DRY

    Dear all,
    I?m writing to both and I hope to find the root cause. Maybe I don?t looking something that at your eyes is obviously
    Attached some pictures from my archive and now.

    Back in 2009-2011 I worked on my own garage project, a 1980 TA with 95 LT1 swap from a Camaro
    Engine has Eagle 383 crank kit, GM hot cam kit LT4, Golen engine heads ported with the bigger intake valve possible, with matching ported intake manifold from Golen too, Comp Camp 1.6 roller rocker, Manley pushrod guide plate.
    We offer a brand New GM LT1 Aluminum head that is fully CNC ported and will make 500hp with the proper cam and the head comes with Manley Stainless Steel 2.00"/1.56" valves, Comp Cams Valve springs to handle up to .600" lift and hardened retainers and locks as well as screw in studs and guide plates. The heads complete
    Comp Cams Pro Magnum 1.6 ratio roller rockers to work with 7/16 rocker studs
    Comp Cams Magnum push rods
    CNC ported LT1 intake manifold to match CNC ported heads
    After I installed the engine I discovered the brand new EFI connection system so I upgraded to it, see email below from Mike.
    Harness modified by me (I?m a technician formed firstly on wiring, later on engine), base tune by PCM4Less, fuel pressure regulator by Aeromotive set at 58 PSI, Ford red top skinny injector calibrated with data from Greg Banish.
    Cranked, fired up almost immediately.
    The project was suspended for several reason until 2018. Try on March, cranked and fired, not bad, not good, 30 seconds dead.
    During August I finished putting together some stuff to put the wheels and the car on the floor out of the jacks.
    Cranked, fired, died after 1 minutes.
    Spark plug DRY carbon fouling. New plugs, new fuel on the tank, new fuel filter.
    Cranked, fired, died after 1 minutes.
    Spark plug DRY carbon fouling.
    I messed around double checking rocker arm adjustment, fuel pressure, wiring on the injectors and coils, intake leak (with engine running when I was luck it remain on I sprayed some brake cleaner looks like no intake leak)
    I changed spark plug several times, at least 4 or 5 set (OEM ACDelco, then #3 ACD and not NGK 3951), I changed O2 sensor, I checked the camshaft pin for false reading on sensor according to EFIC instruction, I try several calibration adjust with HPTuners, no luck
    I hooked up another fuel gauge, I confirmed I have fuel pressure spikes (more than pressure setup), so I lowered the regulator to 44 PSI and adjusted value in HPT, no way.
    Put OEM LT1 regulator, fuel pressure is perfectly stable no more spikes but again keep fueling the spark plugs dry carbon
    Try also 2 set of spark plug wires. Checked fuel injector for leakage.
    Checked engine compression, all cylinder nearly 200 PSI
    I read on EFI-Connection about the crank sensors.
    I have the OLD EARLY 2 row style reluctor with matching L21 BBC crank sensor, it reads on the HPT scan tool and also the positive and negative cam sensor count are perfect.
    I try the PC123 sensor with new wiring, no crank reading at all, obviously.
    I?m really OUT of any options. I?ve read everything I can on books, Service Manual, and

    (FYI I did already several LS modified with bigger heads camshaft, stroker kit or whatever, I did already some 24x conversion on L31, on LS7, on LQ4 and the engine running out immediately. Then you need to tune the VE, SPARK, FUEL, MAF and so on, that?s fine? but if the engine does not starts? what to do!)

    Let me know PLEASE what you recommend to do or to check.
    Thank you so much guys for your time reading this.
    From enthusiast to enthusiast I appreciate any help.

    Christian MUNER
    Attached Images Attached Images

  2. #2
    Advanced Tuner
    Join Date
    Sep 2017
    Posts
    736
    Has it been tuned?
    1997 30th SS. Torqhead 24x, TFS heads, 223/235 cam, 4l80e, S60 D1SC 14psi

  3. #3
    Potential Tuner
    Join Date
    Nov 2018
    Posts
    4
    If the crank and cam sensors are reading right and not over retard, its sounds like a mechanical issue. compression, and check for a bright blue spark.

  4. #4
    Advanced Tuner
    Join Date
    Sep 2017
    Posts
    736
    Quote Originally Posted by H88AUTO View Post
    If the crank and cam sensors are reading right and not over retard, its sounds like a mechanical issue. compression, and check for a bright blue spark.
    True. When I hadnt tuner idle well my car would retard timing bc of the overspeed and it would do this
    1997 30th SS. Torqhead 24x, TFS heads, 223/235 cam, 4l80e, S60 D1SC 14psi

  5. #5
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Lake of Como - Italy
    Posts
    219
    tons of spark plug set later...

    1) the camshaft dowel pin MUST be cut. even if it was BELOW the lower reluctor area it was making interference. +12 signal was more than 360? let's say nearly 370?, and this makes ECM impossible to find when to fire

    2) air gap on CKP it's deadly important. I put the CKP on a lathe, shawed away 0.60 mm, put it to spec at 0.80 mm air gap and the engine FIRED immediately
    BTW, I had ALWAYS the CKP showing reading on scan tool.

    that's crazy, but it works for me!

    bye !!!!

  6. #6
    Tuner in Training
    Join Date
    Aug 2018
    Posts
    26
    Quote Originally Posted by Christian GM View Post
    tons of spark plug set later...

    1) the camshaft dowel pin MUST be cut. even if it was BELOW the lower reluctor area it was making interference. +12 signal was more than 360? let's say nearly 370?, and this makes ECM impossible to find when to fire

    2) air gap on CKP it's deadly important. I put the CKP on a lathe, shawed away 0.60 mm, put it to spec at 0.80 mm air gap and the engine FIRED immediately
    BTW, I had ALWAYS the CKP showing reading on scan tool.

    that's crazy, but it works for me!

    bye !!!!
    It is running well now? Good job on fixing and thanks for the info.

  7. #7
    Advanced Tuner
    Join Date
    Oct 2008
    Location
    Mebane NC
    Posts
    475
    Thanks for the info on the CKP. I'm also running a LT1 24x conversion using the same timing chain cover you are as well as the OLD EARLY 2 row style reluctor with matching L21 BBC crank sensor. Started my project back in 2008 so I know what you mean about delays. How were you able to measure the air gap? Measuring from the face of the sensor hole to the reluctor?

  8. #8
    Advanced Tuner
    Join Date
    Oct 2008
    Location
    Mebane NC
    Posts
    475
    FYI I checked mine since I currently have the engine out of the car and it's @ .032.

  9. #9
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Lake of Como - Italy
    Posts
    219
    Quote Originally Posted by DrLoch View Post
    Thanks for the info on the CKP. I'm also running a LT1 24x conversion using the same timing chain cover you are as well as the OLD EARLY 2 row style reluctor with matching L21 BBC crank sensor. Started my project back in 2008 so I know what you mean about delays. How were you able to measure the air gap? Measuring from the face of the sensor hole to the reluctor?
    exactly, in 6 different point just to be sure the reluctor was not out of round.
    I had a consistent reading.
    you're PERFECT under the specs Mike told me between 0.030 to MAX 0.040
    BTW, me too. I started the project in 2008! now it's time to go out the garage.
    I love to share the feedback to help other, I gone CRAZY for weeks chasing my tail!

  10. #10
    Advanced Tuner
    Join Date
    Sep 2006
    Location
    Lake of Como - Italy
    Posts
    219
    Quote Originally Posted by Ellwein Engines View Post
    It is running well now? Good job on fixing and thanks for the info.
    no sadly it's not ok. I opened another thread and will upload info ASAP, but I'm already on the right path to fix it.
    even if will not be EASY