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RHough
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 Posted: Fri Jun 17, 2016 10:47 pm Post subject: Re: Wideband Results |
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I reviewed the logic that sent me down the path to frustration.
The car was a bit rich at very light throttle cruise with this:
IDF 40's
28mm Vents
50 idles
120 mains
F11 tubes
200 airs
From the weber charts and manual 28mm is too small for best HP for a 1967cc engine so 32mm vents should be better.
The rich very light cruise mix and a slightly lean 16:1 as it progressed to the mains. told me to lean the idles and get the mains in earlier and jet richer.
115 main / 28 vent = 4.1
The standard 44 IDF jet stack is 135 main / 36 vent = 3.75
My reasoning was that the 32mm vents should use between 120 and 130 mains
Weber says that a 20 step in the airs is about 5 step on the mains ...
So a IDF40 with 115 main / 200 air is like a 110
110 / 28 = 125
IDF44 with 135 main / 175 air is like a 140
140 / 36 = 124
I figured the 125-135 range should be about right for the IDF 40's with 32mm vents.
The big mistake was going from
28mm vents 50/120/f11/200 to 32mm vents 47.5/135/f11/180 all at the same time.
If I had changed only the idles or only the vents and main stack I would have been fine. Since the very light throttle mixture was much closer to what I wanted I was convinced I had made some big mistake with the vent/main stack combo that caused the lean hole.
Bigger Airs getting the mains to come in sooner is counter intuitive, but I think what happens is that it is easier for the main circuit to start an emulsified mixture out of the jet well than straight fuel.
Driving with the airs out made a small difference. Driving with stupid large 165 (1/16") mains made hardly any difference. Swapping blocking holes in the F11's made little difference. Swapping them for F7's made little difference. I have not found a combo that gets the mains to come in soon enough to cover the lean hole with 47.5 idles.
Only going to bigger idles makes it drivable.
After putting the 28mm vents back in (I can do it in 20 minutes a side now) with these: 52.5/130/F11/238 (3/32" drill) I had my too fat very light cruise, no lean hole, and a too rich main circuit.
This time I changed just the vents.
I now have 32mm vents; 52.5 idles/130/F11/238
Idle quality is great, drivability is great with slow throttle openings and the WOT mixture spikes lean (16:1) for half a second then that car pulls strong at about 13:1.
I think either real 220's might seal the deal or 135/240. The lean spike hesitation when I open the throttle quickly from 2000 RPM feels like not enough pump stroke so I'll wind the adjusters in a turn at a time to see if my seat of the pants dyno is right.
Still haven't found my 50 idles but the car drives pretty darn well even with the off idle mixture at 11:1
I figure the small pile of Weber brass I have is just evidence of a learning curve. Now that I think I'm close I'll try to figure out the data logger so I can compare the jet stack / e-tube combo I have to play with.
Maybe post runs with F-11 - F2 - F7 and play guess the tube from the wideband log ...
Too much fun.
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[email protected]
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| Posted: Sat Jun 18, 2016 7:25 am Post subject: Re: Wideband Results |
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you are using your brain well; thanks for the post!
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RHough
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| Posted: Sat Jun 18, 2016 7:11 pm Post subject: Re: Wideband Results |
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I found my #50 idles!
After warm-up and setting LBI I drove it for a couple of hours:
32mm Vents
50 idles
130 Mains
F11 Tubes
238 (drilled 3/32") Airs
28° advance vacuum hose off @ 3500
Idle is rock solid at 14.5:1 and 900 RPM
Very light throttle cruise is about 12:1 going to 16.7 just before the mains start. 3000 in 4th at 60 mph is 12:1
Moderate street accel sees 14-15 with the hint of too lean hesitation/flat spot at the top of idle/transition.
WOT runs were limited by rain and traffic but are slightly lean, Never 14.7 but in the high 12's low 13's Richer at lower RPM leaner as the RPM climbs.
I think I've tried all the things I can to get the mains to start at smaller throttle openings. Throttle response is super on the main circuit and the engine is very strong in the 4000 - 6000 range. Over 6000 it is still pulling hard but it goes flat (valve float?) at 6300 or so.
Going any smaller on the idles (47.5) makes the lean hole bigger. Going bigger (52.5) covers the hole but puts the 3000 RPM in 4th cruise at 11:1
I have not tried raising the floats from 10mm to 8mm. I'm not sure that trying 3.5 Aux vents is worth a try. I don't see this as fuel pressure related either.
Every change is predictable and repeatable and the car drives very well above or below the hole.
Last thing to dial in is accel pump stroke. From idle going to full throttle kills the engine. In gear momentum keeps the engine spinning so it is just a brief hesitation with a sudden throttle opening.
As I understand it tip in should use the fuel volume in the e-tube well for a bit of accel enrichment. The F11's limit the fuel volume in the well and have bleed holes that work low in the RPM range. My understanding is that F7's maximize the fuel volume in the well and are richer at the low RPM range of the main circuit. F2's are in between the F11's and F7's.
I'll try adding pump stroke in 3 turn steps to feel that effect, then go back to my full lean setting on the pump arms and do the same with F7's.
If I have this all wrong please please please set me straight!
I think I'm almost ready to try more timing in 2° steps to see how that effects the engine.
I can't measure or feel any difference between 87 octane Regular and 94 octane super premium so I'll continue to save 20% on fuel costs.
Oh I tried pulling the velocity stacks off and saw no change, so I put them back on. My dyno and flow bench notes say that a flat plate has to be less than 25% of tube diameter from the intake to effect flow or harmonic tuning. For a 45mm intake the area is 1590mm^2. The area of a cylinder with 45mm diameter (top edge of the tube) 11.25 mm high has equal area as the end of the tube. So a flat plate 11.25 mm away from a 45mm intake tube should not restrict flow. The 1 5/8" stacks are 22MM away from the top of the filter top plate so should not be a tuning problem for either flow or tuned length. I was pretty certain that was not causing the drivability issues, but it was great to have someone notice and get me to drive with the stacks off to double check.
Time to feed the dogs and stop dreaming of nasty weber bits.
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[email protected]
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| Posted: Sat Jun 18, 2016 7:59 pm Post subject: Re: Wideband Results |
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If you have access to a lathe take .010" off the OD of the F11s.
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RHough
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| Posted: Mon Jun 20, 2016 7:33 am Post subject: Re: Wideband Results |
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| [email protected] wrote: |
| If you have access to a lathe take .010" off the OD of the F11s. |
That will be a challenge. It has been years since I worked with a lathe.
Looking at the E-Tube chart comparing a F11 to other E-Tubes in the series it looks like a F3 has the same bleed hole pattern as the F11 with the only difference being the major diameter is 7.5mm of the F3 vs 8mm on the F11.
A turned down F11 would be 7.75mm so about half way between a F3 and a F11?
I have F2's coming so I could drill those to add the "F" level bleeds below the shoulder like the F11's and make F3's out of them.
I'm not clear on how that will bring the mains in at smaller throttle openings. I'd like to understand how these changes work.
I have another 100 miles or so on the car. Going 3 turns richer on the accel pump has helped the snap open throttle response. I'll go a turn leaner each day until the snap open throttle hole returns to find the minimum pump stroke required.
I used to have a little flask to measure pump volume when I was doing 3bbl solex's on 911's. I may have to build another one to get actual pump stroke volume rather than rely on number of turns on the pump rod. I think I should see a momentary too rich mixture when the pump volume is too big?
I'm starting to think that I'm not going to be able to get this right.
For a lean cruise mixture to work the spark has to advance since the mixture burns slower. The is almost no vacuum at the advance port at a 3000 RPM 4th gear cruise. The carbs are still on the idle circuit. The advance vacuum does increase as the throttles are opened to the lean spot between transition and mains. There just is not enough load on the engine to get to the point where I have enough vacuum signal for spark advance. I need that vacuum signal in the 2-3000 RPM range and it is only about 2".
If I could get the 2-3000 RPM mixture at 16:1 with no hole before the mains I could use a black box to get spark advance with that low vacuum signal.
Pretty far off topic for a wideband thread, but it is all interrelated.
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[email protected]
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| Posted: Mon Jun 20, 2016 8:17 am Post subject: Re: Wideband Results |
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are you using an anti-pulse valve? Have you verified the vac advance is working smoothly and fully (no sticking/binding)?
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RHough
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| Posted: Mon Jun 20, 2016 1:10 pm Post subject: Re: Wideband Results |
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| [email protected] wrote: |
| are you using an anti-pulse valve? Have you verified the vac advance is working smoothly and fully (no sticking/binding)? |
Yes and yes
I've driven the car monitoring the vacuum signal at the advance port. It reads about 2- 2.5 in of vacuum at cruise load/rpm
It goes as high as 5 in of vacuum at larger throttle openings.
I haven't plotted the vacuum vs advance curve yet. I just wanted to know what the range of the signal was and what the signal is at cruise RPM. I have not rechecked it with the current jetting but I will this afternoon.
I miss not having a distributor machine to make it easier. But those are hard to come buy these days and not much in the last 20 years still uses a distributor. I used to pull the dist to set dwell and advance curve on every major tune. Those days are long gone and I should have bought the darn machine for $100 when I had the chance. 
So much easier to lock the dist and use a control box for timing curves these days.
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[email protected]
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| Posted: Mon Jun 20, 2016 1:17 pm Post subject: Re: Wideband Results |
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to me it sounds like your engine has a mechanical problem (poor compression, poor vacuum).
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RHough
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| Posted: Mon Jun 20, 2016 8:03 pm Post subject: Re: Wideband Results |
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| [email protected] wrote: |
| to me it sounds like your engine has a mechanical problem (poor compression, poor vacuum). |
That would be bad news. It is a new pro build with about 30 hours on it.
I rechecked the vacuum advance. It is not butter smooth but it starts @ 2" of vacuum every time. It reaches full vacuum advance about 7-8" of vacuum.
Driving the car I get 2-3" vacuum at 2500 in 4th with the mix now at 12.5. 3000 +/- in 3rd I can get a steady 3-4" of vacuum. The highest reading I have ever seen is 5".
I tried 130, 145, and 135 mains with 230 airs in F2 e-tubes.
Top end is high 12's and I think I saw a 13.1 close to 5800.
The low end of the main circuit at WOT with the F2's is 10.4 - 10.6 *and* part throttle is 16-19 lean hole.
I think the high holes in the F2's (same as F11's) are the lean hole at part throttle. The small diameter body (7.5mm) is the too rich WOT.
I'm going to try going back to the F11's with top holes plugged with the 135/230 jet combo.
I can get the nice lean to rich reaction from the transition/main circuit just not at the small throttle openings at cruise.
I took a carb off to look at the ports and took these photos:
Idle setting with lowest transition hole about half covered. This is 950-980 RPM. It will idle 100RPM lower but the voltage drops with lights and wipers running so I set idle just high enough to keep the alternator running.
Here is the start of vacuum advance port opening.
And this is all 4 transition ports open and the vacuum advance port fully open.
I do see 2-3" of vacuum at cruise and the maximum signal is 5" This must be close to the throttle plate position to give those signals.
Interesting note: the throttle bores are much smaller than the manifold openings. This should act as a reversion dam to prevent backwards pressure pulses in the carb. Mixture flows easily past the step going in but not coming back after the intake closes.
If there was a vacuum or mechanical problem with the engine I would not expect the engine to run so well at such small throttle openings. The HP requirement at 3000 RPM in 4th has not changed from the stock 1600. The new engine makes that required power at smaller throttle openings than the stock engine did. I pulls from 1500 in 4th to white knuckle speed. It is crisp and strong to over 5000 in 3rd.
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[email protected]
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| Posted: Mon Jun 20, 2016 8:46 pm Post subject: Re: Wideband Results |
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just plug ONE bleed hole in the F11s. 2 is too drastic a change. You have to make changes slowly one at a time or it's very easy to get completely lost.
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RHough
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| Posted: Mon Jun 20, 2016 11:16 pm Post subject: Re: Wideband Results |
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| [email protected] wrote: |
| just plug ONE bleed hole in the F11s. 2 is too drastic a change. You have to make changes slowly one at a time or it's very easy to get completely lost. |
I agree. At least I'm keeping notes so I can return to known combos after I screw it up.
Plugging the top two holes made a difference plugging the second set made no change. But that was many jet stack combos ago.
The last no hole combo was F11's with the top 4 holes plugged, 130/238. This was no drivability issues, a little lean 13's going to 14+ at the top end.
I'm going to return to that to verify a starting point. Then try the 135/230 combo to look at WOT. Make sure I'm not flirting with 14+ anywhere at WOT.
Then I'll open one hole at a time to see when the lean hole becomes a problem again. Once I'm there I'm going to surrender.
I'm on track with the car next weekend and I know I have a track drivable main circuit as long as it is between 11 and 13:1
Thanks for bearing with me. I know you have many demands on your time and knowledge.
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modok
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| Posted: Mon Jun 20, 2016 11:28 pm Post subject: Re: Wideband Results |
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You might consider that if f-2 is worse then f-15 or f-9 might be better.
Not that you should spend all your money on brass, but if you are motivated it's worth a try. Since the only difference is diameter the f-9 can be converted to f-15 anyway by removing a mere 0.2mm from the OD.
I have never heard of a case that required f-9 but several where f-15 proves better, but, then again very few bother to try f-9 at all, so, it's unknown. |
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RHough
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| Posted: Wed Jun 22, 2016 7:44 am Post subject: Re: Wideband Results |
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| modok wrote: |
You might consider that if f-2 is worse then f-15 or f-9 might be better.
Not that you should spend all your money on brass, but if you are motivated it's worth a try. Since the only difference is diameter the f-9 can be converted to f-15 anyway by removing a mere 0.2mm from the OD.
I have never heard of a case that required f-9 but several where f-15 proves better, but, then again very few bother to try f-9 at all, so, it's unknown. |
With limited experience and not trying a bunch of combos my conclusions so far;
F11 - Plugging top holes reduced the lean hole
F11 - Plugging second row of holes (4 total) made little change
F7 - Still has lean spot but now way too rich at bottom of main circuit
F2 - Big lean hole *and* too rich at bottom of main circuit
So my SWAG is that the bleed holes above the shoulder of the e-tubes are what effects the start of main circuit. F-2 and F-11 have the same bleed hole pattern there. The length of the wide portion of the e-tube and the diameter effect the volume of fuel in the well. When the throttle is opened relatively quickly the volume in the well provided a little richness like a power valve on a Holly. Then the fat portion of the e-tube effects the lower third of the main RPM range. The F7's were much richer than the F11's with the top holes plugged. The F2's are almost as rich as the F7's in the same RPM/load conditions.
There are also some physics going on here that are hard for me to understand. The mass of fuel in the well plays a part too. At steady load the system flow and mixture are constant. When the throttle is opened both the air and fuel have to increase. The air accelerates faster than the fuel in the well so I would expect any change in throttle to be slightly lean as the engine rpm changes. Having some 'extra' fuel in the well that gets used helps cover the slight leanness. If the volume in the well is too small the mixture will be too lean during acceleration. If the volume in the well is too large the extra mass prevents it from reacting as quickly as it could.
This is consistent with what I've seen with the F11 - F2 - F7 progression. The F11's (smallest well volume) are most responsive at mid range and don't go dead rich at WOT. The F7's are the least responsive and the richest at WOT. The F2's fall between the two.
A stack of brass and an engine dyno would make pretty short work of this.
Plotting bleed area vs well volume for the e-tube range might be worthwhile.
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modok
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| Posted: Wed Jun 22, 2016 5:29 pm Post subject: Re: Wideband Results |
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| RHough wrote: |
So my SWAG is that the bleed holes above the shoulder of the e-tubes are what effects the start of main circuit. F-2 and F-11 have the same bleed hole pattern there. The length of the wide portion of the e-tube and the diameter |
........creates a calibrated gap, the size of which feeds fuel to the air holes in the tube. Smaller gap makes initial start easier but restricts at mid-high flows. Think of a paint gun, has a air jet and a nozzle. A little nozzle works good at low flow rates, a big one doesn't. The diameter of the tube is also a JET in a sense. using the smallest gap that will work also helps to use the surface tension of the the fuel to keep the fuel level in the well right at the step. Make it less touchy about float level.
Tubes with sets of holes lower than fuel level give more acceleration enrichment. For instance f-4 in small CC you will have a rich bog if you try to downshift.
f-2,f-15, f-9 have no low holes so the diameter "changing the volume of the well" is not a factor.
Holes could be grouped into low mid and high. mid is at fuel level.
High holes delay start.
Mid holes make the start stronger (not sooner, just stronger)
low holes makes mid flows richer and high flows leaner, and adds acc enrichment.
And of course......there is no perfect explanation, and there are no definite rules, but each time we do some back and forth, try to explain it, I think I get better at explaining it.
But....at any rate, all you've learned so far is that the lean spot is not IN the main system. I would have told you to try a big main and see if that covers it, and if not, no emulsion tube will solve it. That's my method. I won't be pissed if you prove me wrong, so try the f-9 and 140 main. |
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RHough
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| Posted: Wed Jun 22, 2016 8:41 pm Post subject: Re: Wideband Results |
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| modok wrote: |
| RHough wrote: |
So my SWAG is that the bleed holes above the shoulder of the e-tubes are what effects the start of main circuit. F-2 and F-11 have the same bleed hole pattern there. The length of the wide portion of the e-tube and the diameter |
........creates a calibrated gap, the size of which feeds fuel to the air holes in the tube. Smaller gap makes initial start easier but restricts at mid-high flows. Think of a paint gun, has a air jet and a nozzle. A little nozzle works good at low flow rates, a big one doesn't. The diameter of the tube is also a JET in a sense. using the smallest gap that will work also helps to use the surface tension of the the fuel to keep the fuel level in the well right at the step. Make it less touchy about float level.
Tubes with sets of holes lower than fuel level give more acceleration enrichment. For instance f-4 in small CC you will have a rich bog if you try to downshift.
f-2,f-15, f-9 have no low holes so the diameter "changing the volume of the well" is not a factor.
Holes could be grouped into low mid and high. mid is at fuel level.
High holes delay start.
Mid holes make the start stronger (not sooner, just stronger)
low holes makes mid flows richer and high flows leaner, and adds acc enrichment.
And of course......there is no perfect explanation, and there are no definite rules, but each time we do some back and forth, try to explain it, I think I get better at explaining it.
But....at any rate, all you've learned so far is that the lean spot is not IN the main system. I would have told you to try a big main and see if that covers it, and if not, no emulsion tube will solve it. That's my method. I won't be pissed if you prove me wrong, so try the f-9 and 140 main. |
Your description makes sense. Just to get a feel for where the bleed holes are in relation to float level I used a black Sharpie to 'paint' the a F11 above the shoulder ("E" level holes) to the top flange. It looks like the float level is between the "C" and "D" level holes.
Plugging the top "C" level holes does make the main circuit start sooner.
I was hoping to find a change that brought the main circuit in too early. No Air Corrector and a 165 main. I forgot to note is I had F11's or F7's in for that experiment.
With both C level holes plugged and one of the D level holes plugged drivability is pretty good. I can drive through the lean spot that only goes to 16.8 - 17.0:1 on part throttle acceleration.
From 3500 constant in 3rd going to WOT I saw the 17:1 for and instant then 13.1 - to 13.8 at over 4500. I was about to tune that out by adding accel pump stroke.
I've raised the floats to 9mm for the next test loop.
Next step is to toss 140 Mains with the modified F11's and 230 Air
I'm not getting the soggy 10:1 mix that some of the F7 combos gave me.
If I understand your description correctly the low holes are the "F" level holes on the Weber E-Tube chart? Thus the F11 with 4 holes at the F level should give more acceleration enrichment than the F2's?
What remains is that even with a 165 I have a lean hole with a 47.5 idle jet. Going to a 50 idle makes it drivable but the cruise mix is too rich.
I agree that my 2500-3000 RPM cruise mixture is not a main circuit problem. The problem is that going leaner on the idle jets to get a decent cruise mixture creates a hole you could drive a Combi through.
I could jet it so the cruise mix is closer with 45 idles then drive it like an idiot using a huge pump squirt to get into the mains and tell everyone that its the cam ...
Problem is that it pulls like a train from just off idle when it is rich enough to mask the transition. It has more low end than my Focus. It could be so sweet if it didn't have to be pig rich to cover the transition.
I have 130 through 145 mains and 200, 220, 230, and 238 (3/32") airs. There are several combos that a quite nice to drive.
Thanks for the reply and explanation on e-tubes!
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modok
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| Posted: Wed Jun 22, 2016 10:21 pm Post subject: Re: Wideband Results |
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| RHough wrote: |
It looks like the float level is between the "C" and "D" level holes.
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It's probably lower than that, but without a good way to measure it's actually hard to know.
The fuel level should be at the step or slightly below with this type of emulsion tube. The e-tubes with angled holes at the step are intended(IMO) to allow a lowish float level to be used, for amazing resistance to g-forces. Compared to most others, It feels like they will run upside-down, and that's pretty cool.
If the fuel level is above the E level holes then it will give a slight delay followed by a momentary rich spike when the mains start.
The angled holes don't work very well if submerged, because to get air to flow though them then a lot of fuel has to get out of the way.
They don't have to be angled.... and I made some that were not, and they did seem to work.
All that said the float setting and fuel level can vary. for instance, I use a 200 needle/seat brand X, how will that compare to 175 made by brand Y, and how heavy is the float? and how strong is the little spring in the needle? and how high is the fuel PSI ect, can get different results for sure. |
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RHough
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| Posted: Thu Jun 23, 2016 7:52 pm Post subject: Re: Wideband Results |
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| modok wrote: |
| RHough wrote: |
It looks like the float level is between the "C" and "D" level holes.
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It's probably lower than that, but without a good way to measure it's actually hard to know.
The fuel level should be at the step or slightly below with this type of emulsion tube. The e-tubes with angled holes at the step are intended(IMO) to allow a lowish float level to be used, for amazing resistance to g-forces. Compared to most others, It feels like they will run upside-down, and that's pretty cool.
If the fuel level is above the E level holes then it will give a slight delay followed by a momentary rich spike when the mains start.
The angled holes don't work very well if submerged, because to get air to flow though them then a lot of fuel has to get out of the way.
They don't have to be angled.... and I made some that were not, and they did seem to work.
All that said the float setting and fuel level can vary. for instance, I use a 200 needle/seat brand X, how will that compare to 175 made by brand Y, and how heavy is the float? and how strong is the little spring in the needle? and how high is the fuel PSI ect, can get different results for sure. |
Final setup:
1967cc
W-120 Cam
1 1/2" primary dia CSP Python header with 1 3/4" collector nozzle
IDF 40's
32mm Vents
50 idles
140 mains
F11 tubes with top 4 bleeds plugged
230 airs
9mm float level
Drivability is very nice.
Low speed is still rich at 12:1 +/-
17:1 lean spot before main circuit start in 2nd at part throttle accel
Lean spot is drivable and smaller in 3rd and 4th (larger throttle opening to accelerate)
WOT is 12.1-12.7 3500 - 4500 RPM
Still clean and crisp above 4500 but I was watching the shift light not the wideband.
Probably not going to chase it any father.
Cheers. I've learned a tone and I can give shiny weber brass tree ornaments to my friends ... or maybe a wind chime ... 
_________________
92x74-1967cc; 9:1; L5 Heads; W-120; 1 1/2" CSP Python; Weber IDF 40 |
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Motor60
Samba Member
Joined: July 13, 2014
Posts: 625
Location: SoCal
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| Posted: Mon Jul 04, 2016 3:35 pm Post subject: Re: Wideband Results |
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Ok, Im back at it...
2054cc
8.6 compression
engle 110 cam
40x35.5 heads
dual 44 idfs, 36 Vents
52 idles
140 mains
200 airs
SVDA Dist 8/28 timing
Out of frustration, I started over again...
I hooked up a vacuum gauge and to carb port and opened up the idle screws until I saw vacuum. then backed it off till no vacuum. My engine is idling way too high....I also used the "ear" method...opened up idle screws while listening to other end of hose...engine idles freakin high and snail reads 9-10....I cant remove enough timing to get idle to come back down to the 800's....it idles in the 2000's....Am I doing this wrong? I was trying to get the butterflies as close to progression holes as possible...the only way to get idle back down is to back out the idle screws...
Started over because when I take off hard, the engine falls flat on its face for a few seconds then takes off with great acceleration...like its searching for fuel....
So im back in the game of tuning with my LM-2....the only thing that could throw off my readings is I have the Vintage Speed Superflow exhaust...and Im using the bungs that are welded into the muffler...not sure if that will make a difference with tuning...I'd like to figure out how to properly set the idle screws first before I start messing with jetting again...thx |
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[email protected]
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Joined: August 03, 2002
Posts: 12785
Location: Salt Lake City, Utah
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| Posted: Mon Jul 04, 2016 5:04 pm Post subject: Re: Wideband Results |
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Try 6BTDC at idle. Are the bypass screws all the way shut?
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Motor60
Samba Member
Joined: July 13, 2014
Posts: 625
Location: SoCal
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| Posted: Mon Jul 04, 2016 6:52 pm Post subject: Re: Wideband Results |
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Yes bypass screws are closed. Floats set 10/32. Fuel pressure 3 psi.
I do wanna try the hose in the water trick for the vacuum.
But even if I go down 2 degrees at idle, that does NOT do anything to bring idle down. |
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