| Author |
Message |
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
 Posted: Sat Oct 25, 2014 1:55 am Post subject: |
 |
|
| Quote: |
| My carbs will run leaner than your Injection. |
My car is fuel injected and runs like it has a bad carburetor.  With IR being common with acvw's ,FI and carburetion are not as far apart as with other vehicles.
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
 |
fastfil
Samba Member
Joined: November 25, 2006
Posts: 356
Location: Sunshine Coast, AUS
|
| Posted: Sat Oct 25, 2014 3:32 am Post subject: |
|
|
It's nice to be able to drive from sea level to the mountains without losing tune. Also, tuning is much faster with EFI - how much does dyno time cost?
By the time you've tested and changed timing and jets (usually in awkward places) a few times, you'd be half way to installing your fuel return line and pump.
On the other hand, if you want to run carbs, run carbs!
_________________
"...swingaxle...transaxle...same diff." |
|
| Back to top |
|
|
miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
|
| Posted: Sat Oct 25, 2014 6:38 am Post subject: |
|
|
| itHaKa wrote: |
| At the beginning it ran for only 20 seconds then changed spark plugs, rerouted wires, and got better, but at the end always failed, then sent it to a tech that moved the coil drivers out of the case, ran ok (for some time), went for a drive, made 10 blocks, had to push my car back, and said this is it, I'm going back to carbs and distributor. never got to fix it, as i said, i got tired. |
So you tried ONE TIME to fix a well documented issue with Megasquirt and gave up- you're either lazy, or didn't want it to work from the beginning. That's the same exact thing as someone buying HPMX's and giving up after one jet change, you must realize that right?
If you were running a distributor, the most likely culprit was input noise to the ECU and lack of filtering (this is covered in the Megamanual). If crank angle sensor was used, did you have suppression plug wires and resistor plugs like you're supposed to? I can go out to my car right now and install non-resistive plugs and have noise problems, change them back and cure the problem. Again, if you read the manual it's in there. Just sending the ECU out to get 'fixed' does nothing on your end if YOU were the problem with a bad install.
Remember: MS is USER INSTALLED. The hardware does what it's supposed to do no matter what, it's just a computer so garbage in garbage out applies. Feed it a crappy signal the result is obvious. Your situation is not unique, neither is your lack of follow through or system bashing as a result. I suggest you try again, only this time FOLLOW THE MANUAL!
| Quote: |
| The whole process of fi is installation from the beginning, the ms1 was built from scratch as you know it is a do it yourself ECU one bad resistance or solder and there will be issues. |
So you're now blaming the failures on your lack of soldering skill? C'mon man! They sell these things prebuilt too, it's not much more than a kit. There is only ONE point of failure in this whole story...
| Quote: |
| sorry if you dont believe me, i wish you where there to help me pushing my car |
If I had been there, it would have run right from the start but that's besides the point. The point is if you don't follow instructions, it's going to bite you. It really sounds to me like you were treating MS like a Holley bolt on injection system, expecting it to be flawless off the shelf. That's not going to happen because like I said before, it's a user installed system so it's up to YOU the owner to make sure it's done right. So stop blaming MS for your shortcomings, if it's not for you that's fine and maybe you SHOULD have bought Big Stuff 3 or some other prebuilt system. But I can't stress enough what the MS guys say right on the main page before you even buy anything:
http://www.megamanual.com/MSFAQ.htm#whatis
| Quote: |
| MegaSquirt controllers are experimental devices intended for educational purposes. MegaSquirt controllers are not for sale or use on pollution controlled vehicles. Check the applicable laws in your locality to determine if using MegaSquirt is legal for your application. Experimental means that YOU are responsible for sorting out some details of your fuel injection that are specific to your application. Do-it-yourself means that you save money by assembling it yourself with a few basic tools and comprehensive instructions. |
_________________
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. |
|
|
| Back to top |
|
|
Eaallred
Samba Member
Joined: May 18, 2003
Posts: 5756
Location: West Valley City, Utah
|
| Posted: Sat Oct 25, 2014 7:29 am Post subject: |
|
|
| modok wrote: |
| My carbs will run leaner than your Injection. |
Well, no.
I can tell my injection to run as lean as I want, at any rpm and manifold pressure I choose, without affecting any other mixture anywhere else in the map. Heck, I even shut off the injectors during a downshift scenario. Don't get much leaner than that! lol
_________________
Eric Allred
You have to remember something: Everybody pities the weak; Jealousy you have to earn. |
|
| Back to top |
|
|
Eaallred
Samba Member
Joined: May 18, 2003
Posts: 5756
Location: West Valley City, Utah
|
| Posted: Sat Oct 25, 2014 7:30 am Post subject: |
|
|
It sounds to me like the guy did a poor job installing it, refused to learn it, and is blaming it, instead of himself.
Wonder if he blames the carbs if the floats aren't set right, fuel pressure isn't set right, jetting isn't right, or linkage isn't synched?
_________________
Eric Allred
You have to remember something: Everybody pities the weak; Jealousy you have to earn. |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Sat Oct 25, 2014 10:32 am Post subject: |
|
|
Modok's statement was about cold weather fuel enrichment. One of the top reasons carburetion was replaced was a effective method to do this. Carburetors have to idle high with the choke on because the low temp enrichment works off the cruise circuit or the like. An electric choke is nothing but a heater attached to your carb.Jetting a carb once is no big deal and you feel like man after you get it dialed in right. I like to keep old school second cars carbureted myself. SU's really should have been developed more in my opinion with someway to combat not having an accelerator pump.
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
|
| Posted: Sat Oct 25, 2014 10:50 am Post subject: |
|
|
| theKbStockpiler wrote: |
| SU's really should have been developed more in my opinion with some way to combat not having an accelerator pump. |
They do have an accelerator pump, just not the one you're thinking of (from wiki):
"The damping (of the dashpot) is asymmetrical: it heavily resists upwards movement of the piston. This serves as the equivalent of an "accelerator pump" on traditional carburettors by temporarily increasing the speed of air through the venturi, thus increasing the richness of the mixture."
SU's are indeed a fine carb, if I didn't love Webers so much I might have one on my only carbureted car- the Corvair 180 Turbo. But nothing beats the look and sound of a DCOE on a Corvair, it's like dual quads on a V8. 
_________________
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. |
|
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Sat Oct 25, 2014 4:22 pm Post subject: |
|
|
A lot of the SU carbs do not have one, it is not needed, as the delay in opening the slide produces acc pump action.
But with more powerful engines this delay holds you back.
Thus invented the slide valve carb WITH accelerator pump, such as mikuni HSR.
The dellorto and alfa models of weber (web-orto I call them) have incredible atomization in the idle/transfer system. Injectors cannot duplicate this.
how they run in the cold is quite amazing.
A equally developed FI system probably could do even better...........but of course it will take a lot of work, knowledge, and luck to make a FI system that "is to EFI" what the dellorto "is to carburetors". |
|
| Back to top |
|
|
RHough
Samba Member
Joined: May 12, 2013
Posts: 299
Location: Canada
|
| Posted: Sat Oct 25, 2014 5:07 pm Post subject: |
|
|
| modok wrote: |
The dellorto and alfa models of weber (web-orto I call them) have incredible atomization in the idle/transfer system. Injectors cannot duplicate this.
how they run in the cold is quite amazing.
A equally developed FI system probably could do even better...........but of course it will take a lot of work, knowledge, and luck to make a FI system that "is to EFI" what the dellorto "is to carburetors". |
That great atomization is a manifold away from the intake valve. What happens when it hits the back of the intake valve as it closes?
Cold start, idle and low throttle operation is one of the reasons that OEM gave up on carburetors decades ago. Fuel atomized by a port injector very close to the valve and timed so it does not spray on the back of a closed valve is the solution for drivability, economy, and emissions.
I like the stupid simple carburetor too. They are a good match for the stupid simple air cooled VW.
No ACVW has ever had the power and drivability that a modern EFI car has. My 2014 Focus gets 160HP from 2.0L and is dead smooth and quiet. I'll consider myself successful if I can get 130HP from 1.9 in my Ghia with decent street manners.
Too bad the market does not exist for a similarly priced to Webers EFI system that is as complete as the carb kits on the market.
That said I am sorely tempted to try EFI on my Ghia. |
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Sat Oct 25, 2014 5:24 pm Post subject: |
|
|
| RHough wrote: |
That great atomization is a manifold away from the intake valve. What happens when it hits the back of the intake valve as it closes?
C |
Some sticks and some bounces off. The spray from an injector is not as good in this respect, since not a atomized and uniform mixture, which has had time to vaporize somewhat on the way down.
Mixing air with the fuel is a good way to atomize it, of course. Injectors do not normally do that. You may not be aware most FI systems spray when the valve is closed.
Without enrichment the FI won't run at all in cold. These carb HAVE cold enrichment system but will run well in cold without them!! Easy to prove!
The pentroof four valve head, and port injection is a real good combo, since you have a big port in which the fuel spray can inhabit, can use a radical angle of attack to tumble the mix past the hot exhaust valves without too much airspeed throwing the coarse fuel droplets at the walls. That's a classic design, I'm afraid you can't get as good results just by putting an injector on a DP head. |
|
| Back to top |
|
|
Quokka42
Samba Member
Joined: December 02, 2010
Posts: 3117
Location: Melbourne, Australia
|
| Posted: Sat Oct 25, 2014 5:59 pm Post subject: |
|
|
One of the "pros" of EFI is the superior atomisation, particularly at low rates of fuel delivery - I don't know where you get your idea your carbs are better at this. You aren't going to get much vapourisation travelling down a long, cold manifold. Getting that bit of vapour to commence ignition in a cold engine is a problem for any system, which is why mixture is enriched, allowing the spark to produce the initial vapour that can be ignited. Most modern EFIs can be set up to delay the delivery of fuel at low airspeeds to prevent it "hitting the back of the valve," though a little of this is good, as the valve tends to be hot enough to cause a little vapourisation. EFI can drop the enrichment quicker as it is not needed once the combustion chamber gets hot, plus it does it intelligently instead of relying on a heater and bi-metal spring or an operator. Many here are running dual carbs which due to their proximity to the heads and tendancy to run richer are run without chokes anyway.
_________________
There has only ever been one man who was perfect, and they nailed Him to a cross. |
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Sat Oct 25, 2014 6:41 pm Post subject: |
|
|
Of course what is atomization anyway? "emulsion" might be a better term than "atomization", or some combination of them.
Analogy:
A air powered paint gun, when used as flame thrower, makes a much more compact flame than an electric one. I don't recommend testing that for yourself  |
|
| Back to top |
|
|
RHough
Samba Member
Joined: May 12, 2013
Posts: 299
Location: Canada
|
| Posted: Sat Oct 25, 2014 6:41 pm Post subject: |
|
|
| modok wrote: |
| RHough wrote: |
That great atomization is a manifold away from the intake valve. What happens when it hits the back of the intake valve as it closes?
C |
Some sticks and some bounces off. The spray from an injector is not as good in this respect, since not a atomized and uniform mixture, which has had time to vaporize somewhat on the way down.
Mixing air with the fuel is a good way to atomize it, of course. Injectors do not normally do that. You may not be aware most FI systems spray when the valve is closed.
Without enrichment the FI won't run at all in cold. These carb HAVE cold enrichment system but will run well in cold without them!! Easy to prove!
The pentroof four valve head, and port injection is a real good combo, since you have a big port in which the fuel spray can inhabit, can use a radical angle of attack to tumble the mix past the hot exhaust valves without too much airspeed throwing the coarse fuel droplets at the walls. That's a classic design, I'm afraid you can't get as good results just by putting an injector on a DP head. |
Two ways to look at this.
EFI requires cold/warm up enrichment because it does a much better job of delivering an atomized mixture to the cylinder. Warm settings can be so much leaner they must be made richer during warm up.
Carbs are so poor at delivering a well atomized mixture to the cylinders they must run richer mixtures all the time, thus very little or no cold enrichment is required.
I was a journeyman technician with Datsun/Nissan and was one of the first licensed smog repair technicians in California. I was on the front line in California during the steep learning curve as the factories tried in vain to get a few more years out of carburetor systems. I know first hand how much cold enrichment a carburetor system requires while the engine warms enough to drive on good warm/lean settings. The L-Jetronic system with port injectors was much better even before they went to sequential.
The proof is the superior economy and drivablity of the modern EFI engine while meeting emissions standard that no carburetor could hope to match. EFI is also capable of making more HP. Fuel injection systems do not require any manifold pressure drop at WOT to deliver fuel. IIRC the best carbs still need 1-3in" of vacuum to work.
I love carbs for their simplicity and the fact they don't need the magic smoke that electronic fuel injection runs on. But I know better than to claim they have superior fuel delivery.
A dual webber VW can have a lean stumble hot and still start and run with a bit of feathering the gas pedal. An EFI car would just start, have fast idle, and go about its business with all the soullessness of a Honda.
Me, I'm installing a wideband to help my effort to get the VW to run as well as the Focus. I love my webers ...
|
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Sat Oct 25, 2014 6:47 pm Post subject: |
|
|
| I do not think we had any cars with IR carbs in that era, nothing like a dellorto for sure. |
|
| Back to top |
|
|
RHough
Samba Member
Joined: May 12, 2013
Posts: 299
Location: Canada
|
| Posted: Sat Oct 25, 2014 7:51 pm Post subject: |
|
|
| modok wrote: |
| I do not think we had any cars with IR carbs in that era, nothing like a dellorto for sure. |
IR = Individual Runner?
You are correct very few (if any) cars made is out of the 70's with IR carbs. In fact there were very few cars ever that had IR carbs as OEM.
I did a quick check and found this:
| Quote: |
| Before Dell’Orto stopped production of car carburettors, Dell’Ortos were fitted as standard equipment to Alfa Romeo and Lotus, until the catalytic converter killed the carburettor off for new cars in 1992. |
I know for certain they weren't sold in Califonia and probably not in North America that late in the game.
It is very interesting that the Dell'Orto UK site would link the demise of the carburetor to the catalytic converter. This sort of supports the idea that a carburetor cannot deliver the correct mixture reliably. It would be child's play to modify the power valve system to a duty cycle solenoid and have a closed loop fuel system. That approach got a few years out of other carbs.
Dell'Orto now makes some very good looking EFI systems. If they could have improved the carburetor to match the performance of EFI why didn't they?
I don't want to argue. I like carbs because I can get instant gratification with a screw driver. They are plenty good enough for a hobby car owner by a motorhead. However they cannot compare to the precision of modern sequential EFI.
Cheers,
Randy |
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26785
Location: Colorado Springs
|
| Posted: Sat Oct 25, 2014 9:14 pm Post subject: |
|
|
The weber and dellorto carbs used on Alfas though the 80's did become the most highly developed of their kind, many small design changes compared to the ones of the 70's, which is what todays "webers" are.
dellorto was bought out of the car business, and the tooling destroyed. Maybe the company that did that also made catalytic converters.
Weber also never sold the improved weber IDF to the aftermarket, not sure why, probably no one asked for it. Car buffs don't drive in the cold and don't care about emissions right???
Ultimately, what kills IR carbs is you can no longer have vented float bowls! Emissions after being parked 
FI is great but most advancements are two steps forward, one back. sometimes just one forward, one back, and your in the same place but stepped in a different puddle. |
|
| Back to top |
|
|
rs58rag
Samba Member
Joined: August 22, 2010
Posts: 419
Location: riverside,ca
|
| Posted: Sat Oct 25, 2014 9:47 pm Post subject: |
|
|
| FI..maybe someday on the old bug, just happy with the old idf's, ida's, and dcoe's... this is my hobby or hoarding I guess.... |
|
| Back to top |
|
|
Dale M.
Samba Member
Joined: April 12, 2006
Posts: 20379
Location: Just a tiny bit west of Yosemite Valley
|
| Posted: Sun Oct 26, 2014 7:03 am Post subject: |
|
|
| modok wrote: |
dellorto was bought out of the car business, and the tooling destroyed. Maybe the company that did that also made catalytic converters.
|
Or EFI systems?
Dale
_________________
“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)
============================================================
All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ... |
|
| Back to top |
|
|
Juanito84
Samba Member
Joined: March 17, 2012
Posts: 2436
Location: Colorado Mountains
|
| Posted: Sun Oct 26, 2014 9:53 am Post subject: |
|
|
The best carburetor set ups can out perform your average fuel injection system in every way shape and form. But the best fuel injection set ups will leave your average carburetor in the dust in most every way except cost. When it comes down to it, the most developed fuel injection system will out perform the most developed carburetor but will likely cost ten times the price or more.
Whatever you do, have fun doing it. But personally I'm not going too get excited about putting on this new fangled technology on my car until hovering systems become available.
_________________
If a water cooled engine cools its water with air, isn't it just an overcomplicated air cooled engine? |
|
| Back to top |
|
|
theKbStockpiler
Samba Member
Joined: July 07, 2012
Posts: 2316
Location: Rust Belt
|
| Posted: Sun Oct 26, 2014 10:58 am Post subject: |
|
|
Trying to get a carburetor to adapt to changes in the environment would have made them more costly then FI. Cold weather enrichment is the biggest issue other than altitudes in my opinion. SU's had the way better 'choke' mechanism. Blocking off the air inlet and having the car run off the cruise fuel circuit is not very good.It is dirt cheap though. All of the cars I'm acquainted with that perform the best cold have restrictive induction systems if carbureted. If your going to advance the timing until it starts to knock and then retard it ,you might as well try to cut cost by having the fuel system and the ignition system share resources.
I don't think carburetion technology was fully maximized because of mass production bringing the price of semiconductors down. The "electronic carbs" were a stop gap part. For a street/strip car I want a progressive carb set up. If a 4barrel won't work ,I want the next best thing. For mpg and emissions , I'll take FI.
How about Direct Mechanical Fuel Injection for a air cooled vw?
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask. |
|
| Back to top |
|
|
|
