Webber 750 engine

Neil

Are you bringing anything for sale to Bensen Days?
 
A little side note of interest, all those interested in using the "Microsquirt" EFI on their Weber, a new version is coming out soon that will not just be weather resistant but Submersible, it will have a molded plastic case and a slightly different cable connector. I learned of this when I went to order the 8 foot cable from DIYautotune and found out it was out of stock as are the "older" version of the Microsquirt EFI , probably will not be restocked for sometime (if at all) with the new version coming out soon. They are shooting for even a lower price on the new version.

Searched the net and found another supplier of the Microsquirt that still had the version like I got and also had the 8 ft cable in stock, ($85 plus shipping less than $6 ) so I ordered one. The reason for ordering one of the longer cables is that I will be mounting my EFI inside the cockpit and going thru the firewall with a multi-pin plug, so the cable will be in 2 parts. By ordering the long cable I will be able to cut it to the length I want inside the cockpit and the length I need in the engine compartment and still have the exact same color code and labling on the wiring .

After looking at the bulkhead multipin connector that I got from Diyautotume (in a previous post) I have about decided to use a different connector. This one is a good set up and well made but quite large and I think I want one out of metal probably one from Amphenol (found the type and model # in Mouser finally).

The company that still has the older Microsquirt and cables in stock is www.efisource.com

Tony
 
On the matter of the idle set up, got a new IAC valve from Randy at Watcon and as best I can tell it is a FIDLE valve, or in other words a vavle that is controled by a PWM signal much like a injector, around $130 so not cheap but there is according to the instructions, a PWM output for idle valve control. If I can find a "idle speed control" solenoid I think I will be inclined to make a bracket for it and use this method instead of a IAC valve. A idle speed control solenoid is usually mounted on a bracket in such a way that the plunger "bumps" the throttle shaft open a set amount and hold it open for fast idle until the engine warms up and the computer cuts off the power to the solenoid and drops the engine back to normal idle. This is controled from the engine temp sensor.

Tony
 
I have a good question.... it is my understanding that everyone on here will be using this engine for aircraft purpose.....

So the only time the motor will be at idle is on the ground, so correct me if I am wrong...

The only reason to have an IAC is when you plan to idle at higher altitude... something you won't do in aircraft.... as you would on a sled or bike... so why not have a manual valve to bypass the air to the intake to adjust idle speed? similar to how carburated aircraft have an enrichment lever? when you taxi or are in flight the throttle plates will be open and the MAP sensor and TPC are in control, correct? the MAP sensor/TPC combination signal to the ECU how to adjust the wastegate valve to make sure you getting full boost to the engine when at altitude.
 
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Hey Michael

That's about correct, this idle thing is really only about the time when you start up a cold engine, as in "fast idle". All the other times the engine would be on "idle" (landing , ect) the engine would be using the "idle setting" that is adjusted on the TB's for the normal idle of a warm engine. Rich fuel mixture on a cold engine using EFI is controled by the ECU monitoring the engine temp and adding extra fuel if the engine is cold.

Tony
 
ok just asking..... the only reason to have the IAC from what I read is so you do not have to adjust the throttle body idle for every change in altitude for compensate for idle.....

so in a way i guess i can see why you aircraft guys need it if you are flying out of several different airports with different elevation.... otherwise if you are a local flyer only you dont really need it.
 
To all the guys interested in the Microsquirt EFI

Was doing a little more "close" reading of the info on the Microsquirt wiring and see that it is capable of recieving control input from a "FLEX FUEL " sender. Thought that was a little interesting as this EFI/ECU has been basicly designed for BIKES/PWC/SLEDS and smaller engine applications but will also run a V8 at competition level.

Tony
 
Have a question for the A&P/IA/ and designer types

Given a choice which would be the better or more desireable design, EFI fuel pump in the cockpit or in the engine compartment (open cockpit).

Tony
 
I would keep as many fluid lines out of the cockpit area as possible. Less chance of being sprayed if something goes wrong.
 
I don't know, pressurized flammable liquids on a flamming hot ixhaust, how does that sound?

Tony
 
new connectors for ECU cable

new connectors for ECU cable

The first picture is of the bulkhead connector I ordered from DIYautotune, although nice, it is plastic and rather large so I finally found the type I wanted in Mouser Electronics catalog. It is made by Amphenol and is metal with the pins molded in, gonna be a bitch soldering in the wires, but I have done it before, the secret is to start at the center of the group.

The connector on the upper left is the one that mounts in the firewall and the group on the right is the parts that make up the housing for the cable that goes to the engine. The ECU cable will be cut short, (maybe 10 inches ) and soldered to the back side of the bulkhead connector and be inside the cockpit. This connector only has 17 pins but these will be used for data wires that are low current and another connector with maybe 8 (or more) pins but large pins will be installed for carrying various high current wires. The battery cable will feed throught to a prime terminal on the firewall.

The two Amphenol connectors cost about double the plastic ones but will be helpful in shielding the sensitive (shielded ) timing wires from the cam and crankshaft timing wheel .

Tony
 

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new 8 foot harness vs 30 inch harness

new 8 foot harness vs 30 inch harness

Got the new Microsquirt 8 ft harness in today (almost identical) and noticed one small difference between the two. The 8 ft harness does not have the jack installed for the programming like the 30 inch does, the wires are there but the jack is not installed. Guess they left it open because you may want the jack at the end of the harness instead of at the plug, no big deal. Hope on the new version they will give you the option of ordering either the short or long cable (at extra costs of course) so you won't have two cables.

That little black thing is the ECU, small but POWERFUL ! Don't remember if I mentioned it in the last thread but this thing can except info from a flex fuel monitor and then run gasahol all the way up to E85, it is also capable of running 2 map sensors ???

Tony
 

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Some of the marine versions of the Weber run dual MAP sensors.... have not figured what each controls... one is on the boost side and one is on the vacuum side.
 
The race is on....

The race is on....

Well found someone that can machine an adapter to go from Rotax 101.6 to and SAE II pattern that I need.....

So now I am just waiting for ASE to finish testing in May sometime as I think they still have some flywheel weights to work out for the TC motor....

Also still curious about what Neal is going to have available....

The AERO show in Europe at the end of April plus Benson Days here in Florida soon will tell us the story of what will be out there soon.
 
No Flyweel installed

No Flyweel installed

Looks great, still have my doubts if this well work. The Weber will not work with the wright Flywheel. This is the most imported part on that Engine.

“Believe it or not” Only my opinion… after testing more than 2 yaers..
Maybe I’m wrong!

John
 
Sorry John.... I removed the picture because I did not want this to become an issue between competitors..... as that reduction I was showing is the product of a branch of Swiss Motor Engineering - "Aero Swiss Engine"

The picture I showed contains two flywheels in the bottom housing.... basically the damper assembly has and inboard flywheel and damper assembly and an additional outboard flywheel before it attaches to the lower gear on the reduction...

I look forward to seeing what Rotortec will have available after AERO as you mentioned in your previous email.

I am still shopping around and have not definitively selected the reduction I want. Have you developed a single belt reduction that you liked? Last I saw was a double belt that keeps the prop more towards the output and as you know I would like to lower the engine down below the prop centerline some.
 
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To any and all

Has anyone found a source for the TPS cable connector. Randy at Watcon is looking but have not heard of any luck from him. The TPS is manufactured by CTS and the damaged connector that I have has the iniltials P.E.D. on it but have not found the manufacture yet. There appears there are probably more that 2 dozen different types of TPS designs and that is just in automotive.. Thought I would be able to back track the CTS manufacture but keep coming up with Cadillac automobile. Thought it might be a division of Delphi electronics but no luck there either. This may come out of Germany ??

Tony
 
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