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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
 

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While I know much about lt1 engines, the 24x conversion & other mods you have done puts your project out of my knowledge zone.

I suggest you try over at the gearheadefi forum. Fuel injection & pcm tuning mods are their specialty.
 

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While I know much about lt1 engines, the 24x conversion & other mods you have done puts your project out of my knowledge zone.

I suggest you try over at the gearheadefi forum. Fuel injection & pcm tuning mods are their specialty.

Have you tested the injectors are firing? Have injectors got power 12v?.
Clicking, noid light or pulling rails to test for fuel. ( be aware of fire risk if pulling fuel rail).

Spark? Are plugs firing ? Test with plug in lead grounded out on motor.
Earth/ground staps ok on motor to battery?

Does pcm see engine speed change. LT1 pcm shuts down fuel if min rpm,s aren’t reached.

Is vats still enabled on pcm? Might need the 30 or 50 hz signal.

Does it start if fuel sprayed into manifold?

Mitch
 

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Discussion Starter #5 (Edited)
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 scan tools ALWASY shows CKP reading, regardless of gap!

that's crazy, but it works for me!

bye !!!!
 
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