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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 1:53 pm 
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So all this latest dyno testing was done with E85 only carbs, correct? :-k

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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 2:07 pm 
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That day we first made a baseline pull with the shop 850 Holley on 110 octane gas. It made 529HP@7100 and 434TQ@5300.

Then we flushed the fuel system, put in E-85, and begin working on the E85Demon and the E85Dominator.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 5:33 pm 
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What is useful to do is divide the BSFC by the Corrected HP and thats the actual power made as an uncorrected figure. Its the real power the engine made just like it would on a real day out at a race track. You need to do that because as the weather changes the combustion is affected in ways that are not accounted for by correction factors. There are all these formulas out there that are supposed to correct the power to a standard test atmosphere so that relative changes over time can be made. However these formulas are only accurate if the air conditions change less that 4 %. The SAE have recently 'upgraded' at least one of their correction factors to be supposedly accurate at air changes of 8%, but I think thats BS when applied to hotrod motors. Stock motors with small cams for street cars its a valid upgrade but for hotrod motors with wild cams its junk. The problem with hotrod motors is always balancing the compression pressure with the time of compression so that the vaporization job gets done. I go on about this all the time because hardly anyone gets it done right. Plenty of people think they get it done but I can demonstrate and prove to them its not.
Anyway once you have calculated the uncorrected HP (or got the dyno guy to print you one out because he can, its in there, they just dont give it to you normally) you can then figure the CFM consumption of the engine related to the amount of power it made. To calculate the CFM just multiply the uncorrected HP by 1.21. That gets you close enough answer. If you have logged manifold vacuum you can calculate it via the venturi size to add further accuracy to the answer. You would have to change the venturi discharge coefficient slightly for the differences between the demon and the dominator designs. Dont forget its wet flow too.
Why you do this is because its the simplest comparison of how efficient each tuneup is. With the tools you have available its the only way to proceed. Then you can plot the Wideband AFR relative to the CFM. So once you have done that you can use the WB readout for how its following the amount of fuel consumed verses the air consumed. Small fluctuations can be ignored but large discrepancies may require further investigation by gas bench as to what the gasses actually are. If you see one carby or tune standing out from the rest with a bad result then you can figure out where the engine lacks something. Ignition performance from the electrical side is one thing, but how the flame kernel forms is another and as you change atomization, especially by changing from demons to dominators, you alter the vacuum in the intake and that alters the percentage of gas state fuel passing the intake valve curtain. The flame kernel starts as laminar flame and its greatly affected by the gasification level. The burnable AFR affects the speed of the laminar flame kernel a lot and that relates to the point where the flame becomes turbulent. Once its turbulent the fuel consumption rate increases, thats what you want to get to as quickly as possible. The amount of fuel load burnt at TDC relates to the pressure achieved across TDC. The pressure across TDC doesn't push on the crank for any useful energy to the wheels BUT it does use the energy to further the process of vaporization and consumption of the fuel load, especially in the outer regions of the chamber. The dominator will have less vaporization in the intake tract and that will show up as a power/efficiency loss if the engine has turbulence in the port and its best power will be at more advance than a carby with better vaporization (helping out the port issue). Fuel in a gas state doesnt puddle so you dont end up with a large area of the chamber under the short turn of the intake with excess fuel compared to the rest of the chamber. Engine combos that dont have enough compression to deal with puddling issues need assistance from the intake tract, its just one of the ways to assess how your engine does what it does. As you gain insight into how it does things you can figure out how to improve it.
You observation that the dominator needed to be richer than the demon fits into the theroy that you have port turbulence and fuel puddling to some extent.

So what size is this engine, how much power per cube is it?
What compression ratio is it?
When does the intake valve hit the seat?
What compression pressure does it pump on a gauge?


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 9:13 pm 
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shrinker, I would describe the engine in question as a mongrel. It's leftover parts from everywhere in the shop. You know, a set of new pistons from a job that never happened, some bearings off the shelf, a crank that was sitting in the corner. I do have some info tho.

GM 010 4 bolt block 358 cubes
GM forged steel crank
Scat 6” I-beam rods
Wiseco 13:1 pistons, not sure on ring package.
Cam Dynamics roller, 264/271 duration @ .050, .670/.656 gross lift, 107 LSA, 107 LCA.
A.P.E. ported World Products Sportsman II iron cylinder heads
1.6 rocker arms
Victor Jr intake

I can't tell you about when the intake seats. It's been on the shop Cam Doctor so there's some info around somewhere. The motor sat from Sept. 09 to July this year. We haven't done a compression test but, during the last session a leakdown was done. I don't know for sure but, I think we've done close to 60 pulls all together.

I never expected this engine to make much power. I also never expected it to make any power with a Dominator either (it made 557 in Sept 09 with a 1050 and 110 octane). Quite frankly, (as we don't race dynos) if I were to "race" this motor it would be with the Demon on it and not a Dominator.

I'll have to read the post above again and think about that. As always your posts provide much food for thought.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 9:30 pm 
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Well its very likely doing what I suggested it would be doing. Those heads are at the point where the floor and valve angle are making turbulence for the power your making. I think the saving grace for it is its got very high comp pistons. If it made 557 back 2 years ago then why isnt it doing it now, has it got some rust in it or valve springs gone off etc or is the power on the E85 not that good yet. You may like to put the carby you used 2 years ago on it with 110 gas and see what it is. I think you need to get a baseline that repeats 2 years ago or you could be tuning an engine with a problem somewhere and then all is wasted.
Is it the same dyno, maybe thats it.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 10:02 pm 
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I don't know if the carb used to hit 550 is available as it didn't belong to the shop owner, and wouldn't expect that it would make the same power it did before due to weather differences. We only have what we have done as of late, an 850 and a couple different Dominators on gas, and the Demon and my Dominator on E85. E85 has made the best power, the most torque and the flattest torque curve. On gas the Dominator made more power over the 850, however timing change with the 850 on gas brought the power up and a Dominator has not been run on gas with the timing changes. I do wonder if the Dominator was better than the 4150 on gas (before the timing change) due to the ability of the gas to start vaporizing earlier, allowing the larger carb to perform better on gas than with a smaller/larger carb on E85. And I'll have to go back and look over the sheets, I thought the 1050 hit 529, and looking at the numbers from 7000-7500 the Dominator made a higher average from what I remember. We tried to make the pulls as quick as possible, tried to make some significant changes to see the effects, I didn't have a lot of time to really look at all the sheets. The Demon is a good carb on E85 for sure, at some point I'll do a back to back on my car as well. On the 427 I think the Dominator will be faster on track, but maybe not by a lot. The little 355, I would expect the 4150 to work best and would not recommend a Dominator anyway with that combination. We will do some more testing when time permits, and maybe go back to gas to see the effect of the timing change.

But so far the consistency or predictability of the fuel has been very good, and if the driver did his part it would win more rounds. [-( And $2.80 to $3.30 a gallon is a big bonus. For bracket racing those are both what we want.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Wed Sep 21, 2011 11:15 pm 
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Well thats all good then.
If you log manifold vac and work out the CFM consumption you will probably find the engine pulls more air with the dominator but makes less power per CFM. It's not important it makes less power overall thats from a lot of things you havent tried yet. It takes a long time to do everything doesnt it. But the power per CFM consumed is a good indicator of efficiency and suitability of the different atomization trends for the engine combo.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 2:31 pm 
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The carb that made 557 is no longer available. I have the tuneup out of it. It was a non-HP 1050 3 circuit. It didn't have changeable air correctors so no change was made there. Best power came at 35 degrees timing and the carb was jetted 86H squared.

One problem on duplicating that is between the operator and myself we don't own a 3 circuit 1050. My 1050 started as a 750. Mark's got one I think.

We've talked about conditions not being the same from the original pulls and that even with correction formulas we're not duplicating conditions.

The operator and I have been discussing some other non dyno carb questions, shrinker, you provided the answer in one of your posts above.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 6:24 pm 
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nomad wrote:
One problem on duplicating that is between the operator and myself we don't own a 3 circuit 1050. My 1050 started as a 750. Mark's got one I think.


Had. It just got stripped to prep for the challenge, an old style 9375. I also stripped my old 9377 as well.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 7:50 pm 
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nomad wrote:
The carb that made 557 is no longer available. I have the tuneup out of it. It was a non-HP 1050 3 circuit. It didn't have changeable air correctors so no change was made there. Best power came at 35 degrees timing and the carb was jetted 86H squared.

A 3 circuit carby has a better main jet size relative to the other functions of emulsion and well size and booster etc. The 3rd circuit supplies the additional fuel needed to compensate for the design issues of the main circuit when its taxed at high rate in a large venturi. Basically the 2 circuit option needs such a large main jet that its not the main mixture control point, the well diameter etc become too influential. That's why they developed the 3 circuit carby. Its the easiest way to fix the high load problem. At high load over the range that your testing I would expect a 3 circuit to benefit this engine. Its easy to get rich down low with a 3 circuit and this engine is requiring that, but only when its on the CFM of the dominator. The problem is in the droplets produced by the dominator. There too big.
nomad wrote:
The operator and I have been discussing some other non dyno carb questions, shrinker, you provided the answer in one of your posts above.

Well im happy thats good for you.

The engine needs a 3 circuit carby when its on gas.That makes sense to me and what I think is happening is your comparing the wrong gas carby to your E85 ones. I think at the moment this engine is not as efficient on E85 as it could be or has been on gasoline 110 octane.

This is what your doing, you have a 1050 dominator on a 500hp engine. I say 500 or there about because it likely that's what its making UNCORRECTED, that's what the carby will be actually function as. If you had a 800 hp engine would you use a 1680CFM carb (thats the same size in proportion change). I dont think you would. The carby is too big for the design brief it was made to. It cant atomize the droplets on E85 with the air speed at the lower rev range so you need to richen it up to get the vaporization up enough to get a burn at low revs. The extra vaporization comes from the gasoline part of the E85, that gasoline has chemicals that are low temp distillation and when you richen it you shove more of them into the engine, they turn to the gas state earlier than the ethanol and you get better homogenization of something you can burn efficiently at the flame kernel stage in the chamber.
The 3 circuit maintains better main well emulsion and droplet size because it has a small main jet and its on gasoline. Everything is operating in proper Turbulent mode. Put the 3 circuit on E85 and the bets are off. I would think the 2 circuit would be better on E85 so thats why Im thinking your not as efficient yet. And the reason for that is the heads are taxed at the cams power level your running. The E85 will puddle far easier than straight gasoline. For a start there is more of it in the port and less of it pre-vaporized in the carby barrel.

I realize its good fuel because its cheaper etc but your still a racer and your trying to develop stuff. So hopefully you can use somethings Ive said to think about what areas of the shop junkpile to go looking in to find some better heads etc. =;


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 8:10 pm 
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The Dominator for E85 is a 2 circuit. #3 mainwell taper, .180 angle, .181 booster pin, .185 banjo, 16 - .052 hole boosters, .132 main jets.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 9:52 pm 
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Your booster outlet is only 2.5 times larger area than your jet area and the other parts of the well are even smaller. So you have length ratio issues. That's normal for a turbulent flow condition because once the flow is turbulent the length has reduced effect BUT you have ethanol and its transition point to turbulent is much higher up in flow rate than gasoline. I don't know the viscosity of E85 and I guess not many people do either as it varies in mix etc. So the problem is whats happening in your carby and why isn't it making the same power as the 3 circuit on E85 2 years ago. Its a bummer that you cant retest that carby.
But I think even though your doing OK with your program and your E85 ideas are working etc its still not right. I think none of the E85 carbs are right. Im really having a hard time finding a justification for turbulent flow with ethanol coupled with the current designs of booster in use in holleys etc. The reason I say that is its a bad scene to transition the flow at high power levels. The transition point without emulsification is a step increase in energy needed to maintain flow consistency and continuity of things like AFR curve. Adding emulsion smooths that control problem to manageable results. How to do that at high power levels when there is already significant flow is the problem. Its not like adding emulsion to smooth over the transition when its only flowing 10hp per barrel. At that rate of flow the main jet (on gasoline) is the only part of the circuit that is transitioning, the well diameters are still laminar. But when you go to Ethanol the main jet transitions much higher in the power and at that point the well is also transitioning (because the e-bleeds are working, because the metering block is still the same vertical height part) at either the same time or a different power/flow relationship. Its very difficult to figure out. You may be thinking 'so what, we just have to get an AFR and were getting that OK'. That may be the case BUT the flow type affects the atomization. You have a dominator and its output is around 125hp per barrel so its only the top end of operation that would be turbulent if you had pure ethanol (unknown result for E85). Its the Atomization that changes from the demon to the dominator. You can see that because the WB tells you your richer on the dominator than the demon. The demon is making more power per unit of fuel and its making more power per unit of air pressure inside the engine. Its a better balance somehow because even though your dominator may be feeding the engine more air pressure in the plenum and that should fill the cylinders better for more power the loss of atomization is affecting the outcome.

Thats just what I think.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 10:19 pm 
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I must have mis-spoke earlier. The 3 circuit 1050 two years ago was on 110 octane gas.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Thu Sep 22, 2011 10:38 pm 
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nomad wrote:
I must have mis-spoke earlier. The 3 circuit 1050 two years ago was on 110 octane gas.

Im aware of that. Im comparing the 3 circuit gasoline reasons to the 2 circuit E85 result.


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 Post subject: Re: Another E-85 Convert
 Post Posted: Fri Sep 23, 2011 1:04 am 
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So where does this lead us? How can we make the droplet size smaller without causing turbulence? We are already using a 16 hole annular booster insert, I can drill more smaller holes with blanks, but at what point will the holes be too small? I would think the fuel droplets with the annular would be better than the downleg Demon booster, of course the difference in vacuum at WOT will change the vaporization characteristics so we have to consider that as well. We can put a bar style booster in the Dominator, take out the restriction at the booster to maintain a more laminar flow, but then won't that hurt the dispersion of fuel compared to the annular boosters? I understand you reach a point of too big with any combo, and it may be on this one. We will have to go back to gas to confirm how it responds to the timing changes, we may find it still isn't making the power it once did. I'd like to find the missing power, but at this point I think all we can do is make our basis on what it will do now.


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