Timed my truck tonight

[Trevtron]

Got a Snap-On MT257 pulse adapter from eBay for $160 and Innova 5568 tach and time light from NAPA. Truck has a new Oregon Fuel Injection pump with less than 10k miles on it and just recently purchased pop tested B.B. code Delphi’s (Thanks @Thewespaul).

Had did my best guesswork for timing it as the last time at the truck was timed was at The Oilburners Texas IDI meet last fall....and I was running very advanced then (19*??). Turns out I was compensating for bad eBay Stanadyne D codes...and at the proper 8.5* btdc my truck shook and smoked horribly.

So after I got the Delphi’s in I advanced it a dimes with from the old mark from when it was timed with the bad injectors, as the new ones had retarded my timing and it was obvious. Turns out I was at about 2* btdc when I hooked up my equipment to it.

After getting the equipment on it tonight and getting it timed you’d think I had a new engine installed. Tremendous improvements, I was honestly shocked at the incredible difference a correct fuel system and properly timed engine makes.

I promise no matter how good you believe you are at timing by ear, smoke and mileage it is humbling to see how far off you can be.

Even with my engine starting at the first rotation of the starter when cold and getting 16.4mpg, always track my mpg’s very tanks. I’m particular about that and fuel up at the same pump and only click the pump to the lowest setting to avoid the fuel getting frothy to accurately measure my fuel against my miles.

And hell, I was about 6.5* retarded. Now I have more power, better sound and probably better mpg’s and will confirm after my first fill up later next week.

Will be signing up on the timing registry for Katy/Houston area to give others a chance at realizing their truck’s maximum potential.

Y’all have been invaluable and now I want to give something back.

 

[Hydro-idi]

This is a good point. No matter how good you think you are at timing an engine by ear, you don’t know squat until you actually hook up a meter.
The whole “timing by ear” thing really ain’t worth a damn.

 

[Cubey]

How did you loosen the lower fuel lines at the IP to turn it?

I’m over 700 miles away in Missouri right now, unfortunately.

 

[frankenwrench]

And that's why I'mma pay one of u fine gentlemen to put that fancy timer on my truck when it gets going. I can get a sweet spot where it haze's at best untill wot and sound really nice but realistically I know it was still off. There is no substitute for a number. And numbers are never decieving

 

[Trevtron]

How did you loosen the lower fuel lines at the IP to turn it?

I’m over 700 miles away in Missouri right now, unfortunately.

I’ve never had to loosen more than just the top ones which you can get to easily, have box end wrench that slides over the lines for that job.

FWIW, saw some guys on YouTube use a turnbuckle for the throttle and fine adjustments on the pump. Next time I’m going to try it out, sometimes it pays to work smarter not harder!! Lol

 

[Cubey]

I’ve never had to loosen more than just the top ones which you can get to easily, have box end wrench that slides over the lines for that job.

FWIW, saw some guys on YouTube use a turnbuckle for the throttle and fine adjustments on the pump. Next time I’m going to try it out, sometimes it pays to work smarter not harder!! Lol

Putting too much stress on the fuel lines can cause them to crack, so I read.

I can get the top ones plus inlet with my flare nut wrench. No risk of rounding.

Also, I can’t easily get to the nub on the IP for a 3/4” wrench. A big steel line is in the way. Dunno what that one is, the big one, radiator side with two elbow bends, then heading toward the firewall.

Like in this:

You must be registered for see images attach

 

[chillman88]

Putting too much stress on the fuel lines can cause them to crack, so I read.

I can get the top ones plus inlet with my flare nut wrench. No risk of rounding.

Also, I can’t easily get to the nub on the IP for a 3/4” wrench. A big steel line is in the way. Dunno what that one is, the big one, radiator side with two elbow bends, then heading toward the firewall.

Like in this:

You must be registered for see images attach

That should be the return line from the IP. Mine's rubber, but mine's a 91 too so no surprise they're different.

 

[Thewespaul]

Thanks for sharing this Trevor, the timing equipment is an invaluable tool for working on these trucks and it’s something I encourage every idi owner to invest in. I think another very interesting takeaway from this is the timing difference you saw with the bad injectors versus the new B.B. codes, the same timing mark that was around 12* last fall was 2* with the new injectors. New injectors make a huge difference, and you gotta time the truck any time injectors or ip is changed

Lookin forward to seeing this truck running well at this year’s Texas meet!

 

[Cubey]

When and where is the meet?

 

[Thewespaul]

When and where is the meet?

https://www.oilburners.net/threads/2018-texas-idi-meet.82108/

 

[genscripter]

I've seen this discussion several times on this forum, and I respectfully disagree about the statement that the timing gun is the best way to properly time an IDI. That said, I not supporting the inverse: timing by ear. Instead, I'd argue that the timing gun is only a minor tool in the process of what I call "timing by performance."

I've owned a timing gun and ferret meter for years now. All a timing gun is good for it telling you a number. That number may have very little impact on whether your IDI is properly optimized for timing. So many factors play into the variability of how that particular IDI is "timed," that the arbitrary number is cool to know, but it's not likely the best performance for your engine.

Several factors can alter the "timing" of an IDI: how an IP was rebuilt, the inlet fuel pressure, injector pop pressure and rebuilding, cam and crank variations, different turbo variations, fuel screw rotation, injector line radii, etc. Slapping a ferret meter on and timing it just tells you that you have it to a specific BTDC degree, but depending on your setup, that might not be optimal. When you rotate your IP, you are altering that number, and just because it reads the stock (or turbo) timing spec, doesn't mean that it's done. Sometimes a neighboring timing degree might get the turbo to spool up better. A lot of factors come into play on these imprecise and mechanical diesel engines.

For the most part, getting it close to stock spec would be ok for the average IDI owner. But if you have modified or repaired your engine or fuel system (and who in this group hasn't), then I'd recommend "timing it by performance." This means to time it with a gun to get it to stock spec, then conduct several 0.5deg - 2deg timing variations and drive it, recording MPG, boost, EGT, and other performance data, while carefully recording fuel usage. Eventually, you'll find the optimal timing position for that particular engine. The optimal performance timing might end up being the stock spec, but it might not. It'll take some work to investigate the neighboring degrees relative to the spec.

The timing gun is also good for returning the timing (to the respective previously-tested "optimal" position), if you ever had to remove the IP or do a repair that required you to tear down your injection system. But if you buy new injectors or a pump, then you are back to timing by performance to find that optimal timing position. That's why I don't really take the digital timing spec as gospel. Stock spec might be close to ideal, but with more testing, you might find even more power, boost, or efficiency.

 

[Thewespaul]

You must not realize that this timing spec is what made the highest horsepower and torque on the dyno. This test was performed fairly recently at the east coast oilburners rally with an aftermarket pump and injectors, which you say would alter the spec. I’ve built IDIs with custom fuel systems and turbo setups, making twice as much power as your van and each one had the best performance within the stock spec. If you believe that your certain setup performs better with a certain timing spec then put your money where your mouth is, put your truck on a dyno and get some real data, butt dyno counts for null, respectfully.

 

[Trevtron]

Ill stick with Ford on the optimal timing spec, mine is bone stock and I want it to live a long time. Interesting thing I’ve noticed in all the hot rod shops and engine builders I see weekly is that they tend to rely heavily on their shop equipment...including timing equipment.

I was getting 18.5 mpg on sh*t injectors but running almost 20* advanced when Wes got a gun on the ol girl...and I believed based on performance that with my 1st crank starts, limited smoke and awesome mpg (which I carefully monitored) that my timing was optimal based on performance,,,
Nope.

 

[chillman88]

Ill stick with Ford on the optimal timing spec, mine is bone stock and I want it to live a long time. Interesting thing I’ve noticed in all the hot rod shops and engine builders I see weekly is that they tend to rely heavily on their shop equipment...including timing equipment.

I was getting 18.5 mpg on sh*t injectors but running almost 20* advanced when Wes got a gun on the ol girl...and I believed based on performance that with my 1st crank starts, limited smoke and awesome mpg (which I carefully monitored) that my timing was optimal based on performance,,,
Nope.

So from what I'm reading, just for my information so I'm clear...

You were extremely advanced running the clapped out injectors.

Retarding your timing back to STOCK spec it ran WORSE until you got the injectors swapped out?

I'm asking because I'm pretty sure I'm in the same boat, but there's no swinging new injectors yet, I don't dare until I can get a new pump too. I'm hoping to get a meter on it at the rally. Mine was very retarded when I got it, but there was no bucking/shaking or anything. Just NO power and lots of white smoke.

 

[Thewespaul]

That’s exactly what happened. Truck didn’t start well on stock spec and killed all the mosquitos in the camp ground, didn’t go on the road like that but I’d be surprised if it got above 50 mph the way it sounded