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 Post subject: Re: Another E-85 Convert
 Post Posted: Sun Sep 25, 2011 9:11 pm 
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But will it help with annular boosters? Do I need to go back to my slotted inserts to take advantage of it, or go back to a large hole insert? I guess the question is, is the small hole boosters hurting with E85? And with a similar emulsion setup on gas would we see the same results, is there any benefit to using the small hole booster inserts?


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 Post subject: Re: Another E-85 Convert
 Post Posted: Sun Sep 25, 2011 9:14 pm 
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shrinker wrote:
If you drill a long setscrew and use that for the HSAB you will get better control to complement the staging E-bleeds. Length drag is important to understand and get right.

I don't follow this, are you talking the actual passage length in the bleed itself?


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 Post subject: Re: Another E-85 Convert
 Post Posted: Sun Sep 25, 2011 9:16 pm 
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shrinker wrote:
So what you do now is you try to answer this question. Why is the fuel curve different to how it would be if its was a stock carby on gasoline?


Well now, it's not substantionally different than it was with gasoline (same carb, different fuel). It was more pronounced earlier in the day, meaning there was more of a disparity between low and high RPM AFRs. In one test, we have a collective brain malfuntion and made an e-hole larger when we shold have gone smaller. The result was predictable. The rest of the test varied not more than two or three HP and TQ. Things began to improve (the curve began to flatten) when we went from an .024, blank, .026, blank, blank to an .020, blank, .026, blank, blank. That's when we had the discussion about using more, smaller emulsions in order effect a change in the type of emulsion. The dyno operator shares my philosophy that we won't know it's wrong until we try it and find out. Thus the change to the 014, .018, and .022.

BTW, I just checked the paperwork and this, 014, .018, and .022, is what we had in case I had mis-typed earlier.

Shrinker, I'm not sure about all of what's happened here. I've been transcribing my notes to Logworks and to some new charts I've developed to better organise this stuff and make studying the data easier. I'm sure the lightbulb will come on then. Somehow I'll get that posted when it's done so everyone in this section can see.

What I'd like to do is get this 850 the best we can get it on E85, stick those blocks in Mark's DemonRS, and his 1050 Dominator to see if it works there.

I'm not sure when we'll gat back to the dyno, I believe Kevin has some customers that need dyno time and we'll have to pull ths engine off so he can do so.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Sun Sep 25, 2011 9:27 pm 
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jmarkaudio wrote:
shrinker wrote:
If you drill a long setscrew and use that for the HSAB you will get better control to complement the staging E-bleeds. Length drag is important to understand and get right.

I don't follow this, are you talking the actual passage length in the bleed itself?

yes the actual high speed air bleed in the top of the carby. If you make it long you will get just as much air into the ebleeds at low CFM but less at high CFM. You basically use the length of the jet to create a smaller jet at high flow. It seems to be what your trying to do with the e-bleeds so this may help a bit.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Sun Sep 25, 2011 9:40 pm 
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nomad wrote:
shrinker wrote:
So what you do now is you try to answer this question. Why is the fuel curve different to how it would be if its was a stock carby on gasoline?


Well now, it's not substantionally different than it was with gasoline (same carb, different fuel).
What I mean is to get this flat fuel curve its different. I didnt type it right.
The progression of the e-bleeds is not what you would do to a gasoline carby to get the fuel curve. It means your actually operating in Laminar mode. and moving into transition mode.
Whatever you do with these blocks on the 850 wont work on the Dominator. The Dominator will have less depression in the well because its a bigger carby working at lower CFM for the venturi. The engine power wont change in line with the carby CFM sizes. It will require a larger main jet to feed the CFM with less depression and the e-bleed sizes and positions will have to be different in vertical height. Because the well pressure will be different the e-bleed air flow rate will change too. Stuffing you up. If you put straight hole boosters in the Dominator and not the annular type currently in it, the engine will make more power than on Dominator with annular boosters. I think that would be the most powerful setup but the 850 or demon would be the best carby to drive around with.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Mon Sep 26, 2011 2:42 pm 
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Okay, I understand.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Mon Oct 03, 2011 8:39 pm 
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Made some more dyno pulls on the first. We started with our 850 and made a base pull using our last calibration. Result was pretty much the same. We lost the RPM function on our LMA-2 but still had O2 so we plodded on.

We moved the .014 emulsion down one spot and lost power with that. Moved it back up and increased the bottom emulsion by .002. Lost power again. Moved everything back and reduced the jet from 96 to 94 and lost power gain. We made a final pull in it's best calibration and made 540 HP again. I'm figuring this carb is about as good as it'll get. We didn't have time to work with the Demon as we ran low on time. That's too bad as I want to plug in this calibration in that and see what happens.

We did, however, have a friend bring over a Horsepower Innovations 950 E85 carby. And we made a pull with it. HP and Tq was within one in both cases. The fuel curve was exactly the same as the 850. Our best avg. BSFC was .579 and the HPI 950 was .631.

Correction here: The AVG HP difference ( @5100 RPM)between the HPI 950 and our 850 was only 1 HP. Max power @ 7100 was 530 for the HPI 950 and 540 HP for our 850.

We took the 950 apart to get a good look see. Nothing really special there. It's pretty much the same thing the rest of us are doing. It looks to be an unmachined HP metering block with just two emulsions and the idle jets have been lowered. The mainwell exits have been ball milled. Probably to facilitate an easy turn. The boosters look like they may have had the step machined by Eric. It could be a Braswell. I didn't have a chance to measure the ID of the booster.

The basic calibration is just about what we all use. We could all guess at it and probably be within .001 or so.

Some magazine guy needs the dyno so we're done for a while.


Last edited by nomad on Fri Oct 28, 2011 2:59 pm, edited 1 time in total.

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 Post subject: Re: Another E-85 Convert
 Post Posted: Mon Oct 03, 2011 10:58 pm 
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The ball mill of the crosswell exits is to make it easier to drill them out also. My alky 750s done originally by Rupert are that way too.

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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 12:37 am 
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Thats very good for you. The BSFC with the HP Innovations carby being a lot higher than with yours is a good indicator of poor efficiency from the HPI carby. Your carby will run a lot better on the engine and not stuff the oil and things like that. It would be good for you to investigate the differences between yours and the HPI one and figure out why the BSFC is so much different.
When you say it had the same fuel curve as your carby I assume your referring to the WB data. So do you have 2 different carbys with different lbs per hour of fuel passing through the engine but your getting similar AFR readings?


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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 10:08 am 
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shrinker wrote:
When you say it had the same fuel curve as your carby I assume your referring to the WB data. So do you have 2 different carbys with different lbs per hour of fuel passing through the engine but your getting similar AFR readings?


Yes, I mean the WB info. Both "curves" are relatively flat. Both are lean in the same area and rich in the same area.

The 850 is using a standard non-step booster with a .178 passage. This seems large but, BLP assures me that this is correct. The HPI unit uses a stepped booster of a dimension I haven't checked. I'll have more info later as I just spoke to the HPI owner and he's going to drop the carb by tonight so I can really give it a good going over. As the HPI carb is the one he usually runs, I'm contemplating him doing a back to back test with both carbs one night.

I'd like to add that I'm in no way trying to denigrate Eric's carb or his abilities. I'm just reporting what I've seen so far. I'm just surprised at what I've found.

The owner is really happy with it , I've seen it run, and raced against it.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 11:02 am 
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The 950 is a 1.375 venturi but has a better inlet with the HP body, the 850 has a 1.5625 venturi but has a milled choke tower. The 950 has a custom stepped downleg booster, the 850 a stock downleg. It would be interesting to see wha the actual airflow and booster draw differences are, as well as WOT vacuum readings. It is surprising that what should be a smaller carb that should flow less AND has a higher BSFC average makes right at the same power.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 4:09 pm 
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The HPI carby is less efficient for sure, some improving could be done there but you will have to take manifold vacuum readings to figure it out. I just wouldn't bother with HP style carbs.
I think the 850 with a stepped booster would be best.

Because the BSFC's are different and the AFR lines are the same there must be an error in the WB accuracy. It would be a difference in CO content. The HPI carby would be making more CO and have more HC and O2 left over.
nomad wrote:
Yes, I mean the WB info. Both "curves" are relatively flat. Both are lean in the same area and rich in the same area.
Well then the engine is causing that. You have a combustion efficiency variation at RPM points. It's probably moving the choke and or turbulent point in the port further towards the plenum at higher RPM.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 4:22 pm 
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Shrinker, I'll get into my laptop and see just what the actual AFRs are between both carbs. What I meant by the "curves" being the same is that they looked alike, not necessarily the same AFRs. But let me look at the graphs again to be sure. The O2 sensor was a new Bosch we had taken out of the box that morning.

I've never been able to successfully print a graph off my LM-1 or DL-32 data, though.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Tue Oct 04, 2011 9:29 pm 
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nomad wrote:
Shrinker, I'll get into my laptop and see just what the actual AFRs are between both carbs. What I meant by the "curves" being the same is that they looked alike, not necessarily the same AFRs. But let me look at the graphs again to be sure.


I just had a look see. The AFRs on the HPI carby varied between .2 to .5 AFR richer than the 850.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Oct 05, 2011 1:23 am 
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The difference in AFR has to match the difference in fuel passing through the motor. Do it by percentage calculation.


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