Given 57 Chevy w/ Street & Performance to 96-97 LT-1 to 57 Chevy Hot Rod COMPLETE Conversion with LT-1 to 57 Chevy Wiring kit and 57 Chevy Body wiring kit.


Example story http://www.hotrodlane.cc/PDFFILES/57Story.pdf

LT1 tech Instructions http://www.hotrodlane.cc/New%20LT%20...ge.html#LTtech

LT-1 VIN # 1G1BL52P4TR150127 1996 Impala SS with 4L60E

Minor Problem Fix:
Car ran fine had minor shifting problems before winter but that was in the speed sensor. Replaced speed sensor and fixed transmission shifting and engine surging perfectly. Also put in a bottle of Marvel Mystery Oil in tank for winter. (I am an old schooler) The S&P package replaces original air mass sensor. I have ran this tank of gas out since and filled with new 93 octane.

Other notes
During winter, put car on rack and cleaned under carriage and engine compartment. Replaced # 4 welding cable with 1/0 welding cable and added an extra battery in trunk compartment for extra cranking and amperage capacity primarily for power windows, which now work fast and great. Also ran a # 4 welding cable to engine block for double grounding in addition to frame grounding. Computer was disconnected from any power for 3 weeks.

REAL PROBLEM

After connecting the batteries back up. I started and drove car with continuous minor backfire and miss. After 20 minutes of this the car would run fine. Take back to garage and assume everything fine.
Next time out same thing, continuous backfire and miss over 2K RPM until after driving about 20 minutes then loud backfire through headers and tailpipe and then engine would run perfect.
As I know absolutely nothing about electronic engines, I figured I would drive for a while with LT-1 running correctly which I did. Please understand I ran the dog out of it for 90 minutes routinely to see if a miss at 5500 RPM and ran absolutely perfect. I thought well it fixed itself and was very happy.

Now after 90 minutes of running correctly and I shut off and opened up garage went back to start and would not hit a lick. Actually it was if it was way out of ignition time, as now backfire through intake.
After one hour of cooling down, the 57 started but now runs with a miss and continuous minor backfire again as before. It is as if after driving for 20-30 minutes the car computer ignition times itself correctly and then runs like a champ but shut off and we are back to a LT-1 engine completely out time.

My thinking now is I got too much engine cleaner on distributor opti spark which I am just learning about.

Please what are your thoughts? I guess I am going to change crank sensor and opti spark to new GM stuff and go from there. Is this what you would do? The scanner throws no codes when running correctly but throws a code of 327 and 372 plus 719 weird when trying to start after a running shut off. Here is S&P codes list from programming the computer

http://www.hotrodlane.cc/New%20LT%20...96DTCLIST.HTML

Thanks for your help.

 

....... Opti Spark distributors are allergic to water ... especially when its forcibly applied ...

 

So you think changing the distrbutor and crank sensor will most likely solve my problems ?
Thank you so much for your input. I don't mind changing parts but don't really want to miss something while I am at it. From what I can tell using GM factory new parts is the way to go ?

 

........ Have the ignition control module tested or replaced ... its externally mounted with the coil and a lot cheaper than the Opti ........

 

Water pump leaking onto distributor, top third of distributor looks like it has been under water with rusty corrosion. Changing everything with GM parts. water pump, coil , ignition module, crank sensor, and distrbutor.

Thanks for all the advice and comments it is appreciated.