[TheSilverBuick]

Originally Posted by Fishin2Deep4U

Just a note,

in my conversations with DIY, it appears that we don't gain much with a 58 tooth wheel. In fact, some resolution can be lost at high RPM.

Now, I don't know how much RPM we are talking about here. Maybe they were referring to 14K plus, I really do not know.

Dave

On V8's the important stuff only happens every 90* of crank rotation, and on a 36-1 wheel you have new information to the ECU every 10* of rotation, so what does having new information every 5* of rotation get you? A very small fractional increase in resolution.

MegaSquirt II and III use a count down timer from the last tooth to pass before needing to send fuel or spark. So if you want spark at 32*, when it see's the 30* tooth go by it calculates how much time (in small milliseconds, based on how fast the previous 2-8 teeth went by) after that tooth there should be to attain 32*. With twice as many teeth I don't think you gain anything, BUT if you are looking at 36* to 39* of timing, you may gain a little bit, but definitely talking a small amount since the MegaSquirt timing calculations seem to be pretty good. The error difference is going to be really small because the time/numbers are really small.

[HWYSTR455]

On the XFi, with a 58X wheel, it watches rising edge, plateau, and falling edge. So the way I understand it, that's 174 separate events, which applied to not only timing, but injector control as well. Sounds like a good thing to me. And there's a reason GM went to the 58X wheel on the latest LS engines.

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[BruceWilkie]

Originally Posted by HWYSTR455

On the XFi, with a 58X wheel, it watches rising edge, plateau, and falling edge. So the way I understand it, that's 174 separate events, which applied to not only timing, but injector control as well. Sounds like a good thing to me. And there's a reason GM went to the 58X wheel on the latest LS engines.

.

Agree.
Electromotive uses 60-2 wheel. Resolution is good... Greater resolution = greater accuracy. I used to work on production equipment with up to 1000 count encoder discs(under 3" od fwiw) that ran at some pretty high speeds.

I dont think a 10000 rpm shaft speed is going to out run the speed of electricity at 58 or 60 tooth count.

Whatever system... the software determines whats done with encoding signals.

I can just about gaurantee every rise, fall and gap is seen in the raw signal leaving the encoding device(trigger wheel) of todays efi systems. It should be seeing it.

[Fishin2Deep4U]

I found this quote from one of the Megasquirt manual pages.

" The missing tooth wheel decoder has been tested up to at least 18000 rpm for 36-1 and 60-2 wheels (yes, 18 thousand rpm) on the bench, and works fine"

Contrary to the impression I got.

Heres where I pulled the info from.

http://www.megamanual.com/ms2/wheel.htm ://

So, perhaps a 60-2 wheel could go on the wish list. I have a laser guy we use for some plate we have cut. I might try to get a drawing together and see of he can make me one on our next run of parts.

Of course, if Ollie is going to do the leg work, I will still buy one from him.


Dave

[Fishin2Deep4U]

This is what had me confused, but with the balance of the text I did not see.

" 60-2 works great on most engines too, but is not advised for very high rpms. For very high revving engines (such as motorcycle engines) due to the number of teeth per second, 36-1, 24-1 or 12-1 are preferred."

Now this makes more sense!

Dave

[Ollie]

Dave, Thanks for the plug. Yes I have 36-1 trigger wheels for sale.

[BruceWilkie]

Dave... Ollies 36-1 wheel is fine for 99.99% of us anyway. If the cost is fair(which it likely is) its certainly more conveniant than making one.

I just wanted to clarify that better resolution can be more accurate. Yes there is a point where rpm could affect the read, but it would be pretty high rpm.

[HWYSTR455]

A little digging uncovered the 'limit' of the 58X wheel RPM, which is in the 8000-8500 range, and is an issue when running COP. That's with the factory ECM.

The way to get around that is to use an aftermarket ECM/ECU, or go to a flying mag setup.

.

[BruceWilkie]

Originally Posted by HWYSTR455

A little digging uncovered the 'limit' of the 58X wheel RPM, which is in the 8000-8500 range, and is an issue when running COP. That's with the factory ECM.

The way to get around that is to use an aftermarket ECM/ECU, or go to a flying mag setup.

.

The processor speed can certainly affect things probably other firmware as well. Probably how the software is written as well.

[Fishin2Deep4U]

I am working on the particulars for a half moon poll type sensor for the oil pump drive. I am just going to cut down a distributor or just build a plug myself and use the stock shaft to drive it.

I am sure I can come up with a couple of bushings to make it all work. A simple turned cap will keep it finished off.

I need to figure out what the width and depth of the step area. Plan on making it out of a piece of solid, make a key way, and simply weld another half round to the outside. Turn the top to make it look pretty and I am good.

The reason for the key way is so that I can swap to another profile should I choose. I'll simply secure the assembly with a pinched lock nut.

Dave

[Fishin2Deep4U]

Spoke with John (sp?) at Fuel Injector Connection. He said that EV14 Short would work much better than the standard Picos. They have a 4 hole pattern as opposed to the pencil of the Pico.

The standard 36lb would net over 40lbs at 4bar pressures, so I think they will be plenty big for my application. (Sub 500HP)

And I have decided to use Ollie's setup for the trigger. He's done the leg work, so no sense in reinventing the wheel. No pun intended.



And finally, I am going to go with a stainless tank and the fifth gen f-body pump. I know there are other options, but I have chosen this for my own reasons. Not saying that anything is better or worse, just the system I think will be best for me.

I will just fab up a mount ring and keep it real simple. Also plan on using a top mount fuel level sender.

Dave

[Fishin2Deep4U]

Ordered the new fuel tank today. Also have the fuel module on the way.

Now I just need to decide if I am going to use the Vaporworx mounting ring or not. I most likely will, as time for machining parts is at a premium since I am so busy slaying those spring chinook salmon! I already have a good tig guy that can help me keep the fuel on the right side of the metal.

Either way, Carl at Vaporworx has been a wealth of knowledge and had earned a place on the boat for some northwest fishing!

Dave

[Fishin2Deep4U]

New stainless tank arrived today. No internal baffling, so I will probably skip the corner pickups, but I might reconsider welding in a couple of mounting tabs and using them.

Planning on ordering the Vaporworx ring and modding a 0-90 ohm sending unit or using a stock sending unit with the feed welded shut.

Still looking for a quality ptfe lined house that its reasonably priced. Will most likely go -8 to keep fitting restrictions to a minimum. I will be using hardline primarily, with a short section at the rear and again towards the rail. I will use a Y-block and may integrate a pulsation damper at the rear of the rail.

Dave

[Fishin2Deep4U]

Started cutting into a perfectly good stock style stainless tank. Initial fit of the Vaporworx tray has gone well. Still waffling on what type of fuel sending unit to actually use. Would prefer to use the stock one on the module, but it's 40- 240 ohm I believe. I am going to try to get my hands on an earlier model module to see if I can adapt it.


Dave

[Ollie]

I have a 0 - 90 ohm fuel level sending unit for the 4th gen fuel pump module. Don't know what the 5th gen looks like.

This is another method I was considering, retaining the stock sender, until I found the 0 - 90 ohm.

Just read this posting on pro-turing.com
http://www.pro-touring.com/showthrea...nc-fuel-system

[Fishin2Deep4U]

Thanks for the pics Ollie.

Here's a shot of the one currently in the 2010+ module.




Clearly, they are different. I may just use a universal style sender and mod it to mount to the bucket.

Dave

[Fishin2Deep4U]

Thought I would just update my project.

Pressure tested the fuel tank and have a very small leak that needs repair. I'll hit it with the tig tomorrow hopefully. I am undecided on fuel line material. It will be mostly hardline with a couple short braided lines for some flex. I like the idea of stainless, but it's hard to say. I will most likely go to a swadgelock setup as I can reduce adapters. Our I can plop down the cash for a 37 degree flare and go JIC. decisions, decisions. As a reminder, I am running a 5th gen camaro module dead headed at the rail at 4 bar.

I have all the major components except for the trigger wheel and I'll get that on the way from Ollie when I get a bit closer in the next week or so.

I still have to source a few small parts. But it is looking good for ecm control of the fan, TH400 kick down, and leds for warning lights. I do need to get power into the car to run the system, source a grommet for wiring and some protective sheathing.

So, if the tank gets done, I'll be starting the big changes the end of the week, wiring hopefully next week.

Dave

[Fishin2Deep4U]

Just thought I would put up a quick update.

I have purchased a used Chevy Vortec distributor. This unit has a Halls sensor under the cap as well as a reluctor ring or cup that provides cam position triggering. The one I got is the distributor model. The flat cap unit is uber expensive. And since I am going to cut it up, cheap was the price I was after.

I am going to use this cup as a template to turn a piece or two and be able to use a stock GM sensor in my old points dizzy.

I have successfully incorporated two other designs. And the one that is the cleanest is the adaptation of the Ford Explorer sensor. However, they have been known to drop magnets onto the reluctor causing damage to the reluctor and obviously the sensor. Most seem to feel that this sensor is good for about 80K miles. So, it's a known failure point and I just wanted to avoid that. The other uses a very common gear tooth sensor that actually works very well, can be slightly bigger than the Ford unit. I thought it was too much work to pretty it up and then I am back to a non over the counter part.

So, it's the Chevy unit for now. But I am considering modifying a few dizzies for my buddies with the Ford unit just as a test bed. Of course, these are prototype units and are pretty ugly. Both the other dizzies and in running cars now. My own is still in pieces.

I have gathered almost all my fuel system stuff together. Maybe if I can stay off the river through the Thanksgiving Holiday, I'll get some work done.

The single biggest hurdle is as follows. Where the heck do I put that Megasquirt?? I am leaning towards modding the ash tray and making it mount on a plate behind while keeping the tray front. I will most likely hinge that sucker for access to the ports and SD card. Or maybe I'll just get lazy and throw it under the seat.

I need someone to give me a push.

Dave

[TheSilverBuick]

I mounted mine on the heater box. Just used short screws. Then had the harness cross the firewall right above the A/C and heater box.

Here is the MS2 on my heater box. It fit there with out any modifications to the A/C kick panel cover.


I don't know if this picture will pop up or not, it's giving my browser fits, but it is the MS3 installed in the same place as the MS2, but trimmed up to fit.


Used the stock wire loom brackets under the dash for routing.


And into the engine compartment.

[Fishin2Deep4U]

Thanks for the pics!

I actually eyeballed the same area last night on the bird. That would be a good spot all the way around. I am going to go to a vintage air unit, so this would be a temporary location at worst. And it would give me plenty of wiring under the dash to move out later of necessary.

I am going to run the relay board, out will be interior mounted as well. So, I should have plenty of flexibility. I just ned to decide what else I need to wire and power. I know I need to build a circuit for the COP wiring so I can punch it through with the rest of the harness.

I will also be using one of the spare outputs to operate the kick down for the TH400. Again, I will wire this inside the car. So, I'll need a couple of fuse protected relay circuits to be sure.

I am trying to hide some of the guts of the efi to keep the under hood area looking clean. I did find an old grommet off an old toyota harness I had laying around. gonna be a pretty big hole, but will let me pull the harness from the car if needed at some point.

Dave