tioga

As far as the lore of old webers being better than new here is my take. The skill required to properly set up a set of carbs of any brand is a lifetime of trial and error and lessons learned plus the basic knowledge of how a carburetor and all of its given circuits and components work together combined with the basic requirements of a given motor. The number of truly skilled people able to PROPERLY set up a set of carbs has gone from probably a few hundred in the 70's to a steadily lower number as the decades past and those guys have retired or died. So the chances of someone buying a set of webers in the 90's and having someone properly set them up was very low and got steadily lower as years passed. The number of shops with a full range of idle and main jets, air corrector jets, accelerator pump jets, emulsion tubes, chokes, venturi's, etc. is very low. Plus knowing how each one interacts with each other. Most likely they bought a few richer or leaner jets it ran OK and called it a day. The emulsion tubes for example. The numbering system for them refers only to order they were created. For example a f2 emulsion tube is the second one ever created and a f5 is the fifth. It has nothing to do with how they act. They were created as Weber supplied carburetors for different production cars and race cars and developed new tubes to correctly tune a given motor. So the only way to know what a f2 does vs a f5 is to have tested it or know from someone else in the field who has. The exact same thing exists with Weber idle jets. A 45 f6 idle jet is richer than a 45 f9 but a 45 f8 is leaner than the f9. And this is at some point of the delivery curve of that jet not just plain leaner or richer period but each act different from each other as the flow through them increases. It's crazy to think of all the possible different combinations. Each different idle jet f number was created to solve someone's problem in their motor fueling. So I will bet that most of this lore comes from buying old carbs that were at some point set up pretty well for the car they were on and someone bought that set for their similar car and they worked great compared to their friend who is struggling with their new set. I would prefer a new 40 dcoe 151 over an old 40 dcoe 18 any day. Mainly because they have an air bleed to correct for the difference in flow between the barrels of a single carb. Say the front throat is flowing 3 and the second is 3.5. You can crack open the air bleed on the low barrel and bring it up to match the 3.5 of the higher flowing butterfly. I have also had great experiences with the 45 dcoe 152G vs the standard 45 dcoe 9. the 152g has 4 progression holes on the idle circuit vs 3 in the standard 45 and on a 3.0L big cam motor this carbs works great. That all I have to say.

As far as the lore of old webers being better than new here is my take. The skill required to properly set up a set of carbs of any brand is a lifetime of trial and error and lessons learned plus the basic knowledge of how a carburetor and all of its given circuits and components work together combined with the basic requirements of a given motor. The number of truly skilled people able to PROPERLY set up a set of carbs has gone from probably a few hundred in the 70's to a steadily lower number as the decades past and those guys have retired or died. So the chances of someone buying a set of webers in the 90's and having someone properly set them up was very low and got steadily lower as years passed. The number of shops with a full range of idle and main jets, air corrector jets, accelerator pump jets, emulsion tubes, chokes, venturi's, etc. is very low. Plus knowing how each one interacts with each other. Most likely they bought a few richer or leaner jets it ran OK and called it a day. The emulsion tubes for example. The numbering system for them refers only to order they were created. For example a f2 emulsion tube is the second one ever created and a f5 is the fifth. It has nothing to do with how they act. They were created as Weber supplied carburetors for different production cars and race cars and developed new tubes to correctly tune a given motor. So the only way to know what a f2 does vs a f5 is to have tested it or know from someone else in the field who has. The exact same thing exists with Weber idle jets. A 45 f6 idle jet is richer than a 45 f9 but a 45 f8 is leaner than the f9. And this is at some point of the delivery curve of that jet not just plain leaner or richer period but each act different from each other as the flow through them increases. It's crazy to think of all the possible different combinations. Each different idle jet f number was created to solve someone's problem in their motor fueling. So I will bet that most of this lore comes from buying old carbs that were at some point set up pretty well for the car they were on and someone bought that set for their similar car and they worked great compared to their friend who is struggling with their new set. I would prefer a new 40 dcoe 151 over an old 40 dcoe 18 any day. Mainly because they have an air bleed to correct for the difference in flow between the barrels of a single carb. Say the front throat is flowing 3 and the second is 3.5. You can crack open the air bleed on the low barrel and bring it up to match the 3.5 of the higher flowing butterfly. I have also had great experiences with the 45 dcoe 152G vs the standard 45 dcoe 9. the 152g has 4 progression holes on the idle circuit vs 3 in the standard 45 and on a 3.0L big cam motor this carbs works great. That all I have to say.

With that current fet shape we are sacrificing air flow for fuel shot geometry. Which is more beneficial?

You just passed on a more functional port injector because it didn’t look good. Now passing on a tilted up intake because it looks good but not as functional. The wall wetting you have been obsessing on for the last three + years is not that big a deal. It amounts to an afternoon of tuning your enrichment tables and done. Think about all the American v8’s, Ferrari v12’s lambo’s and every other central v carb motor and all the wall wetting they had but worked just fine when tuned. Plus all the L6 race cars, street cars that made great power with the fuel not nearly as atomized and upstream of every setup you have abandoned.

I would want to angle the throttles up some like the jenvey manifold since we don’t need to keep them level like carbs. It also gets them up away from the exhaust and looks better in my opinion to have the trumpets pointed up a bit. I realize it would counteract the goal of your up swept runner a bit by pointing the injector a littler steeper down but the amount of wall wetting with that short runner and the angles will be minimal. You could also just put the injector at the port like oem’s do and spray the back of the valve directly since you are making your own intake. Though I guess if you are using a e88-e31 etc head the center intake bolt hole will not be there and thus you will have a hard time getting the injector right at the port.

Have you tried the o-ring from a new oil filter?

What is the spray angle of that injector. Not the degree of the cone but the angle the cone comes out at or two cones come out at. With the strange offset injector placement it will be helpful to know so you can try to index it to keep the fuel off the Side of the port. It is hard these days to find single cone injectors since 99% of the motors today have two intake valves.

You should be able to close the plug gap down and see a difference in rpm where the break up occurs if it’s exactly the same issue.

No that is the Luk version part number lsc199 slave cylinder which is aluminum instead of cast iron. Other than that I am using a AEM pressure sender and that is it. The bleeder was m10x1.0 and I have a adaptor in the bleeders to go from 10x1.0 to 1/8npt. I now have the pressure sender running parallel to the slave using a 90* adaptor and it looks better.

This was causing the acceleration enrichment to constantly be applied. Timing would not have changed for that small amount of throttle change. The acceleration enrichment would explain why the main fuel table changes were not effective

The map readings are one of the most important readings. We need to know what they are. Not worried about what a vacuum gauge on the manifold read but what exactly does the map sensor say the manifold pressure is. With a map based system this is your main mixture control device. If you disconnect the vacuum line to the map sensor you will be stinking rich. If the map sensor is not reading correctly your mixture will be way off. You need to know what sensor you have 1bar, 2bar etc. you need to look at the setup wizard In the haltec and make sure it is correct. If you run a 1bar sensor but have a 2bar in your set up the readings will be way off and make the car run rich. 3bar would be worse.

Have you disconnected the o2 sensor to run open loop? I would do that. I would also make sure my coolant temp looks correct. Try it open loop (no o2 sensor) on one of the original tunes that worked. The map sensor readings look correct? 8-15 in-hg or 50-55 or so kpa. Does it read about 95 kpa key on engine off? These are things that will make it uncontrollably rich if incorrect.

I see now it was Ben that First replied not you Duffy. I didn’t even look and that is why The “you guys” Statement didn’t make since. anyway Ben it looks like there are crank errors and a running car> and what does like a haltech have to do with anything. All modern engine management systems use the engine speed sensor the same way, weather it’s BOSCH, AEM, Motec, Keihin, Seimens etc. I have had cars Run like shit from a bad crank sensor. Way more didn’t run but some ran but like the car we have here. This is even more likely when we have a home built stand alone where RF interference and noise have not been necessarily tuned out and tested for. 6 high energy coils in a line make a lot of NOISE.

I’m not sure if you are saying “you guys are all way to smart” because I pissed you off or not. Anyway The clicks don’t go in time is why I said something about crank signal. Because it seem so erratic. I don’t see how cooked windings self trigger. I would expect them to just not fire at all. It seemed like they were firing fine just erratic timing. Crank errors and this issue sure could be related.

The injectors are that out of whack and the car starts doesn’t it? Weather it is from the injector, ecu, or a input to the ecu correct? This tuning you have done was at low rpm trying to tune idle? The duty cycle of the injectors at idle is so low it would be harder to damage the injectors at low duty cycle. I understand the difference between the different types of injectors. They are also pretty robust items that don’t often fail.

The erratic injector firing could also be caused by erratic crank sensor signal. I also doubt the impedance setting did any damage to anything. It seems unlikely that strange rhythm to the injectors is being caused by the injectors. Take a bulb or led and put it across one of the injector terminals and watch it fire. See what the light does. I usually take a #194 wedge base bulb and straighten out the wires on it and it will plug directly into the injector Connector. Then watch the light Tuning your map for the idle air valve will be more difficult. The idle air will be constantly changing. The vacuum on a itb car with Or without a cam Does not have much resolution. So it will be hard to get that part of your map dialed in. You may want to add additional rows to your map down there to help dial in that area. That is why most people tuning this set up use a throttle position based map not manifold pressure. This is the conclusion I came to with the same setup as you. I tried map based but small throttle position changes made little to no vacuum change but did make air flow changes. My map is extremely well tuned now with throttle only. This is also the way Dave at Rebello sets up his tunes. That is also why a simple solenoid idle kicker like I suggested would be better. You can easily figure out the additional fuel required for a constant leak like a idle kicker and when your tune turns it off at say 150* you take it away.

Just in case anyone else ever wants to do this I could find no information out on the web about how much pressure is really in a clutch hydraulic line. Well In out case about 550psi. But you only need about a 200 psi sensor because you want to activate before you reach full pressure. I have a 1000 psi sensor and it goes to about 2.4 volts when the clutch is fully depressed.

Set up a no lift shift tune today on my car. Might be one of the coolest mods yet. It works so well. Set up a 3step limiter with a clutch pressure switch. And rpm limits for each gear at different vehicle speeds when clutch pressure exists. This means you don’t have to do 7500 rpm shifts for it to work you can do whatever rpm you want at the time. The revs drop to what is needed for the next gear ratio. Takes a little getting used to not moving your right foot on a 7k shift but after a few times you get the hang of it. Sounds really cool. Installed the pressure switch in the bleeder hole so no hardware change necessary.

To me the best rear kit out there is the t3 kit. Beautifully built and no problems. I have had it and the front kit on my car for about 3 years zero issues.

That’s fine but not how it was originally used. Having it open some just gives it more ability to actually give you a constant idle. The way you are going to use it You need to set it up with the motor at is lowest possible load, fully charged battery no accessories on, oil full temp, etc so it will never idle higher than when you set it. If you set it up at 20% duty cycle then it can always give your target idle under all conditions. What Ecu are you running?

Thanks Derek. I was very happy with how it came out. Et12K yes it is a Audi sensor. Used through 2005 on lots of different models. Early cars used single window shutter wheel on cam to trigger. You will want one of them. Later cars used multi window of varying size. At least on AEM it requires a full revolution of the cam to sync where single window only needs the one window to pass. The cool thing audi did with the multi window sensor was they could use it in the event of a crank sensor failure and the car ran fine. Not many cars out there that use a crank sensor that will run without it.

It’s Supposed to be set so warm idle gives a 50% duty cycle of the valve.

Yes. Base idle is set at the valve.

I don’t understand this comment