scan tool to set timing

[sundy58]

I pulled the distributor on a VIN J 454. I did not realize it was not adjustable like an old-school engine. I read in my shop manual (after the fact) that an electronic tool is needed to check "CMP Retard on the Scan Tool." I can't afford a pro tool, does anyone know of a scan tool that will check "CMP Retard on the Scan Tool" affordably?

VIN J 454 = Sequential Multiport Fuel Injection, Enhanced Ignition System

[Eyez Open]

You are correct, efi timing curves are controlled by software known as timing tables. Any mechanical changes made to the initial timing starts chaos. As to your issue Google set base timing on efi should give you the results your looking for. I can't imagine needling anything more than a timing light and a shunt for the distributor.

I was wrong, you do need a prog. Tuner pro is free and quite a program. One can actually adjust the maps so setting the base timing should be quite simple. One does need to get a cable that interfaces with a laptop however. There should be many sources for that. Tuner Pro has a very large community.

https://www.tunerpro.net/

[sundy58]

Yes, I was quite surprised to find that a timing light is not even an option to use on this engine. They placed the distributor so the is, at most 10 degrees of motion available. My brother in law who builds hot rods is installing an LS and it does not have a distributor at all. 

[sundy58]

I was wrong, you do need a prog. Tuner pro is free and quite a program. One can actually adjust the maps so setting the base timing should be quite simple. One does need to get a cable that interfaces with a laptop however. There should be many sources for that. Tuner Pro has a very large community.

https://www.tunerpro.net/

I have a 1997 with OBDII. Do you know off hand if Tunerpro works with that? The website says it's for 1985-1995 Chevs

[Eyez Open]

It does, tuner pro is a very robust program. But you will have to have some experience/ background Woking with hardware/ software. There are forums at tuner pro to help you along. It's been 15 yrs since Ice worked with efi and that was Mefi,a offshoot of obd designed for the marine industry. I can be of little use on your setup. But I can tell you it is a absolute pleasure working with carbs and HEI...So simple and easy to obtain results...On par with efi actually if not superior to some degree.

[sundy58]

I was an electronics technician for 45 years. I am not too good with software, I like a GUI way better than a terminal. I do use Linux and manage to struggle through with forums and how-tos.

I will download it and see if I can figure it out. Thanks for the help.

[Eyez Open]

Better do windows, there is enough to comprehend just understanding how tuner pro operates, I can only imagine interface issues with linux.

[sundy58]

I only meant to give some idea of my software experience. I don't mess with virtual machines and so forth. I keep computers with the OS needed to run specific programs. If it's written for Windows, I run it on Windows.

[Eyez Open]

My curiosity got the better of me. There always has to be a mechanical means for setting base timing. So I did some looking around and have perhaps found that method. It sounds like a GM thought process, and is rather quick and simple. Below are two links, one poses the question and later verifys the second links solution...I guess a quick look at the cap might verify the method. And as always one must visit a GM store to dial in the timing for zero margin of error. I love priority tech...gives me goose bumps.

https://www.rme4x4.com/threads/cold-timing-a-1999-7-4l-vortec.102970/

http://www.pacificp.com/forum/viewtopic.php?t=7057&view=next&sid=007a6eac919ef737fdf09a6a1aa4121e

Distributor Installation
Bring cylinder number one piston to TDC (Top Dead Center) of the compression stroke.
Important: Distributor cap screws are not captured in the distributor cap.

Remove the distributor cap screws to expose the rotor.



Align the pre-drilled indent hole in the distributor driven gear with the white painted alignment line on the lower portion of the shaft housing.
Using a long screw driver, align the oil pump drive shaft in the engine with the mating drive tab at the end of the distributor shaft.



Guide the distributor into place.
Make sure the distributor is fully seated in the engine.
6.1. If the distributor is not fully seated, the oil pump drive shaft may not be aligned with the mating drive tab at the end of the distributor shaft.

6.2. Remove the distributor and align the oil pump drive shaft as stated above.





Once the distributor is fully seated, the rotor segment should be aligned with the pointer cast into the distributor base.
• The pointer has a (8) cast into it, indicating the distributor is for an eight cylinder engine.

• If the rotor segment does not come out within a few degrees of the pointer (8), the gear mesh between the distributor and the camshaft may be OFF by a tooth or more.

• If this is the case repeat this procedure to achieve the proper alignment.





Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install the distributor hold down clamp bolt to the lower intake manifold.
Tighten
Tighten the distributor clamp bolt to 33 N·m (24 lb ft).

Install the distributor cap.
Install the distributor cap screws. Do not overtighten.
Tighten
Tighten the cap holding screws to 5 N·m (40 lb in).





Install the ignition coil to the upper intake manifold.
Install the ignition coil bracket bolt (2) and stud (1) to the upper intake manifold.
Tighten
Tighten ignition coil bracket bolt (2) and stud (1) to 25 N·m (18 lb ft).





Connect the fuel injector wiring harness connector to the ignition coil bracket.



Connect the ignition coil wire to the distributor and ignition coil.

[eXodus]

I got an Android Phone and "Torque Pro" as app used that for my 96 Brave with 454 and now my Vortec 350

https://play.google.com/store/apps/details?id=org.prowl.torque&hl=en_US&gl=US

Costs like $5  and is worth every penny.  It reads cmp retard (you need to google for the exact PID code to get it displayed)
A cheap $10-20 OBD2 bluetooth and you are good to go.  (lets you do all sorts of other wizard type actions too, like resetting your service interval lol)

I've set the timing with the Phone app - very easy to do.  Just rev to 2000 rpm and slowly turn the distributor till you are at 0 degree, then tighten the screw.
Clear all codes and go for a drive.  (+-2 degrees is acceptable)
Check again after after few miles when the engine is really hot.

When you are farther of then +-22 degrees initially - then you are probably off by a tooth (and the engine will hardly run)

[sundy58]

Good stuff, thanks.