Fuel Efficient Cam Regrinds : General Info

[Coyote X]

The way it works on a metro is to just drill a new indexing hole halfway around the sprocket. Just make it half a tooth off for 9 degrees since a full tooth off is 18 degrees

[TestDrive]

Thanks for the offer. Please do and any other measurements you might care to take.
The nearest junk yard to me is just over 20 miles away and I have no idea of how far to the nearest you pull it style junk yard.

But it's not just number of teeth.
Tooth shape (round tooth) and belt width to match water pump and camshaft gears.
Shaft hole size to match crank.
Keyway width.

[Christ]

yeah, those are all considered as well, but with most MFG's, they keep a certain standardization to their engines. The 2.3 and 1.9 share a transmission pattern and a few other things, and can be interchanged with the 3.0 FWD or RWD platform without changing the transmission.

3.0's will fit in Escorts. I've done it. :P

I'll probably just walk into the yard and find a couple cars with D-grade engines, then swap the gears on them and see how it lines up/etc. If I can keep proper timing with the new gear, after 4 full turns, then the gear works. If the sizing looks good, it usually is. As much as people would like engine parts to be an exact science, often times, good enough really is *good enough*.

[TestDrive]

Originally Posted by Coyote X

The way it works on a metro is to just drill a new indexing hole halfway around the sprocket. Just make it half a tooth off for 9 degrees since a full tooth off is 18 degrees

Crankshaft sprocket, right?
Does a roll pin or some such go through the indexing hole?
No keyway?

FWIW Already skimmed through http://ecomodder.com/forum/showthrea...html#post26075

If a moderator happens to read this, please change the title of this thread from FE Cam Regrinds : General Info to Cam Timing and Regrinds : General Info

[TestDrive]

Originally Posted by Christ

I'll probably just walk into the yard and find a couple cars with D-grade engines, then swap the gears on them and see how it lines up/etc. If I can keep proper timing with the new gear, after 4 full turns, then the gear works. If the sizing looks good, it usually is. As much as people would like engine parts to be an exact science, often times, good enough really is *good enough*.

I agree.
Probably should have said eyeball rather than measure.
Probably would have said eyeball if I'd know that just swapping gears around might even be an option.
Out here on the N. Central SD prairie, U-pull-it Junkyards are just an urban legend.

[Coyote X]

Originally Posted by TestDrive

Crankshaft sprocket, right?
Does a roll pin or some such go through the indexing hole?
No keyway?

On a metro there is a roll pin on the cam. Just drill a new hole and you are good

I did a test on mine and drilled 4 extra holes and with a combination of moving the belt a tooth and the extra holes I could adjust it to about anywhere. Turns out on a stock xfi cam 3-5 degrees is best and on a stock cam 5-10 is best.

As far as changing the cam profile itself, the best place to ask is somewhere that does custom cams already. Some place like comp cams or lunati. I had a custom comp cam made once for a sb chevy. Not really sure if they do every engine but they would probably be able to wild guess and make a better profile than I could work out on my own.

[TestDrive]

Originally Posted by Coyote X

As far as changing the cam profile itself, the best place to ask is somewhere that does custom cams already. Some place like comp cams or lunati. I had a custom comp cam made once for a sb chevy. Not really sure if they do every engine but they would probably be able to wild guess and make a better profile than I could work out on my own.

Thanks for those leads. Haven't heard back from Delta yet.

I've only been thinking about this for a few days now, but a this point I'm think aero mods first and degree and possibly regrind at the next timing belt interval - about five months for the wagon if I get it back on the road soon. (So ready for the end of Still Winter. We have four seasons here in SD: Almost Winter, Winter, Still Winter and Road Repair. )

[rkcarguy]

I've already thought about this being applied to a vtec engine or others that employ different sets of cam lobes...I'm sure the "low cam" could be ground with less lift and duration to provide more low end torque and better mpg, while still retaining a high power lobe for top end. There would be a bit of a flat spot in the midrange but I'd put up with it for the mpg gains.
Doing this to a regular engine would obviously be at the cost of horsepower but regrinding the lobes smaller should be fairly simple as no material has to be added to the cam like when they make larger more agressive ones.

[Christ]

For most regrinds, even if you're lowering the lift, you're still going to change things like lobe separation angles and duration to get the most efficient cam you can... that said, you'll still need to have material added before you can change some of those parameters while keeping the cam's lift profile tame enough to not start loping when you're idling at 500 or less RPM (yea, you can make your engine idle that low w/ the right cams.)

In fact, the 225 inline 6 cylinder Chrysler engine was noted to have been able to idle at speeds less than 200 RPM, and has once been said to idle at 50 RPM without stalling, but no oil pump function could be recorded at speeds that low.

This would be another advantage of solenoid-based valve timing events, rather than a mechanical cam controlling them. You could have the computer controlled valves opening enough to keep the air flowing reliably into the cylinder at extremely low speeds, still maintaining enough power to counter-act the frictional losses of the engine, which would burn significantly less fuel than idling at 800-1000 RPM for the average engine. Even 600 RPM vs 100 RPM is no comparison in terms of fuel use.

Solenoid based valve action would also allow the engine to be infinitely tunable for it's specific displacement, meaning that after all tuning took place, the engine's only weak point really would be it's displacement in terms of going further for FE or Power.

[Tygen1]

Have you considered asking this question of adjustable cam gears on a ford eskort forum. I thinks it's FEOA or something like that??? There ought to be plenty of knowledge over there.
So what's with the ZX2 being the third string bench rider? They are a plenty fine car, although I see your getting 50+ mpg with your wonder wagon...ZX2 adjustable cam gears are easy to find and relatively afordable...TeamZX2.com...