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Bugman Jeff
Samba Member
Joined: May 20, 2004
Posts: 636
Location: Evansville, WI
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 Posted: Wed Mar 31, 2010 9:22 pm Post subject: CB Performance single knob EFI? |
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My boss, who's been building kit cars professionally for the past 28 years, has an old EFI kit sitting on the shelf. It's one of the early CB Performance single knob systems. I've seen the 3 knob systems, but never a single knob system. It uses mainly GM sensors, a GM computer, and a magnetic trigger wheel installed in a locked out 009. I've never seen a single knob system, and a search didnt turn up anything. He said it was originally installed on a turbo'd kit car, but they were having trouble with interfearance from the plug wires or some such. He offered it to me for my supercharged engine, but I don't think it would be anywhere near tunable enough. Is this system even worth messing with? Anybody have any other info about it? Is it still worth anything? Thanks for the info.
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Restorer of Porsche Speedster 80486  |
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junior55
Samba Member
Joined: October 01, 2006
Posts: 941
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| Posted: Thu Apr 01, 2010 6:06 am Post subject: |
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The two-knob system I have worked with and it has it's shortcomings.
The one-knob I have not heard of but in your tuning, a base curve is not hard to achieve. However this is not the problem with these early systems.
The cpu can be programed by the seller for a usable base curve if he has
info from that far back and you have cc's, injector size, etc.
Your one single knob would I GUESS would give you some mid-to- WOT voltage control?
Assuming they are using a vac-assisted fuel pressure regulator, then here is more of your enrichment system control.
BUT here's the problem with the early systems (two knob).
With the lack of inputs in their so called "simple" FI, you will at best only get it to run fair to ok.
It has its' quirks if your doing full spectrum driving.
Certain conditions such as (high rpm) mid to full throttle acceleration or when the vacuum is high and you punch-it, you will studder!
You will not tune this out!
There are reasons for designing an FI system with ALL the basic FI inputs! |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Thu Apr 01, 2010 6:30 am Post subject: |
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If ignition noise is bothering you, use resistor plugs and supressive leads.
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
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Eaallred
Samba Member
Joined: May 18, 2003
Posts: 5756
Location: West Valley City, Utah
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| Posted: Thu Apr 01, 2010 2:44 pm Post subject: |
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| miniman82 wrote: |
| If ignition noise is bothering you, use resistor plugs and supressive leads. |
Agreed. People thing resistor plugs and high resistance wires lowers power or something, but it certainly doesn't from what i've seen. I've gone faster in the quarter with resistor plugs and wires, because the ignition signal is so clean!
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Eric Allred
You have to remember something: Everybody pities the weak; Jealousy you have to earn. |
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Bugman Jeff
Samba Member
Joined: May 20, 2004
Posts: 636
Location: Evansville, WI
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| Posted: Thu Apr 01, 2010 6:01 pm Post subject: |
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| miniman82 wrote: |
| If ignition noise is bothering you, use resistor plugs and supressive leads. |
This was probably 15 years ago when they were messing with this system, it's been sitting on the shelf since. He said they went so far as to shield all the EFI wires and install shielded w/grounds modern carbon core plug wires(none of that copper core junk so common on these cars) but they were still getting interfearance. They solved it originally by going full distributerless and moving the coil packs well away from the other electronics.
So basically this single knob system is pretty worthless for any kind of performance use? Not enough tunability built into it and the PROM needs to have an initial program setup for the specific application? No wonder they started adding more knobs...
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Restorer of Porsche Speedster 80486 |
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Dale M.
Samba Member
Joined: April 12, 2006
Posts: 20378
Location: Just a tiny bit west of Yosemite Valley
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| Posted: Fri Apr 02, 2010 7:17 am Post subject: |
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If its just the ECU I would just "walk on by".... If its the whole kit (throttle bodies and pump and misc parts - what ever) take it, use the TB and what ever and s**t can the ECU and wire up a Megasquirt ECU system to all "essential" parts....
Dale
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“Fear The Government That Wants To Take Your Guns" - Thomas Jefferson.
"Kellison Sand Piper Roadster" For Street & Show.
"Joe Pody Sandrover" Buggy with 2180 for Autocross (Sold)
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All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ... |
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miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
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| Posted: Fri Apr 02, 2010 7:28 am Post subject: |
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Copper core plugs are the best IMO, but you need to make sure there's an 'R' in the part number to signify resistive. I use Champion Copper, all other plugs woked much worse at any heat range.
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Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
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