Retarding Timing?

[Wyldesoul]

I know it does have some way to retard timing, because it comes with a knock sensor. Mine just doesn't work, so I unplugged it.

I do know that this was the single most high tech car that Ford made in '87. Fanciest, Fastest (2nd quickest)... Real nice. MT car of the year.

I redline at about 6.5k.

[Pyrorocketeer]

how did you know the knock sensor was bad?

If it is, get it replaced, and your FE and power should go up from the added timing.

[Wyldesoul]

Ran the engine codes. Wouldn't register knock even when I rapped a wrench on the intake manifold during diagnostic test.

And a lack of knock sensor in this car doesn't cause constantly retarded timing, it just never pulls the timing, so I just have to listen for knock.

I'll just advance timing to 12* and keep an ear open.

[Pyrorocketeer]

They don't just only pull timing though.... they adjust accordingly. They add timing till the point of knock. If it detects knock, it pulls some out. If working correctly, you should be running on borderline detonation all the time for max power and efficiency. I don't know if they had that kind of technology at that point in time, so I doubt that would be the case. If it was distributorless ignition, then yes. but the old coil, and distributor method, no.

Also the sensors are calibrated to detect the specific frequency at which detonation resonates. I don't think you can recreate what that sound like while hitting the block, or intake mani.

[Wyldesoul]

Modern knock sensors are like that, perhaps, but not this one.
It keeps timing set at whatever you set it to, and if it detects knock, or any similar sound (Which can be recreated by hitting the intake manifold with a wrench.) it pulls timing.

It may be a high tech 87 Ford, but it's still an 87 Ford.

[bobc455]

Originally Posted by Biffmeistro

I'd heard of it done a few times in order to increase FE.

From the nature of your question, I assumed that you meant retarding the cam timing. Everyone else seems to be talking about ignition timing. Which do you mean? (or don't you know?)

-Bob C.

[thisisntjared]

we were just assuming he didnt have adjustable cam gears since he didnt have it in his mods and that he didnt feel like skipping teeth since that would just be a bad idea.

[smay665949]

I used to drive a 79 Z28 Camaro with about a 375 horse 350. I tried all kinds of things to get power and economy out of the car for all round driving. What I found, Stock setting for the original engine for that car was 8 degrees advance with the stock weights and vacuum advance on the distributor. With the upgraded engine I would have to set it at 6 degrees advance to get through emissions. What I ended up with is 18 degrees initial advance adding and aftermarket mechanical re-curve kit that brought it to 38 degrees total advance by 3000 RPM. This gave me instant performance and very little throttle to get up to or maintain speed. As for economy, it didn’t make a difference between 12-18 degrease advance, which doesn’t make sense because I was applying less throttle at 18 than I was at 12.

One thing that may help an older car is a MSD 6A box, that provides multiple spark discharge to ensure complete light-off of the fuel. The one I installed made the engine run smoother from the 5000-7000 rpm range and made a huge difference on cold starting and low-end torque. Surprisingly it did not increase my highway mileage or make my car faster at the track. I never checked my around town economy because I was young, gas was cheap and I couldn’t keep my foot out of it. (Burnouts for the girls!) In my truck this box gives me better economy in the winter.

This car was fast and actually got more 2 mpg with the 375 horse engine than it did with the original 195 horse stock engine.

One thing you can try is hooking up a vacuum gauge to a manifold source and find a level area where you can do some tests. Drive a predetermined speed and read your vacuum gauge at that speed and throttle setting. Then adjust your timing a couple degrees and do it again. If your vacuum goes down you lost efficiency, if it goes up you gained. Keep doing this until you get the highest point.

One thing I want to caution you about. My car had aluminum heads and a large cam with a lot of overlap which relieves cylinder pressure. I pulled this engine out of my car and installed it in my truck along with a smaller cam with less overlap and a smaller exhaust. I can only run 13 degrees initial advance with this cam before it will detonate. Your stock engine will probably detonate if you try to run 18 degrees of initial timing.

Note: My truck and car are both carbureted.

Hope this helps!

[jiggersplat]

jeez... when i had my altima i was running 22 deg advance. you guys are wimps

[ShadowWorks]

I've a question, my engine is suppose to be at 16 BTC from the factory, its a turbo car so it has a vacuum advance on the distributor, I adjusted the timing to 18 BTC as I was told I could run more turbo boost, now I don't care about performance, would having my engine at 18 BTC hurt FE?

If I set my timing to 14 BTC would this help FE?