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Old 10-03-2008, 03:26 PM   #141
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Oh...would anyone mind if I linked this to M.net? It seems we post enough threads from there here talking about how stupid people on M.net are, so it would seem only fair if it worked both ways.

I am sure they would get a chuckle over it.
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Old 10-03-2008, 03:39 PM   #142
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you gays need to get over yourselves and just rub your ***** together.
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Old 10-03-2008, 03:58 PM   #143
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OMG. In the time and effort you guys used having your e-***** battle you could have probably built the motors and proved your theories.
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Old 10-03-2008, 04:06 PM   #144
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I'm not wrong. I'm not in a hole. BSFC is not LIMITED to .5-.6. It's just a number. .5-.6 may be TYPICAL, but it's not the only range of values. If you read said "source" you'll see it says "general values".

If you reread my post on BSFC, you'll see I said the initial value .5 was ARBITRARY. Do you see that? Do you know what it means? I'll explain. It means it doesn't matter. It's simply a point that I choose for illustrative purposes. It could be more or less, but I picked .5 to ILLUSTRATE THAT YOUR PREVIOUS MATH WAS WRONG. Based on my initial numbers, my formulas are correct. I could have used .5 and .55 or .6 and .55 or whatever the hell I wanted. I was showing you how to use a formula you could not figure out how to use. The end. I was not wrong. Stop saying I was.
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Old 10-03-2008, 07:04 PM   #145
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Quote:
Originally Posted by JasonC SBB View Post
I emailed Dema Elgin if he thought higher c/r results in higher VE due to better evacuation of exhaust gas at the top of the exhaust stroke. He replied that he's on holiday and I can call him in 3 weeks.
It does.
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Old 10-03-2008, 07:10 PM   #146
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Originally Posted by jc_rotor View Post
Really, the biggest issue with static CR is the margin of error. It is much easier for the average Joe to run a lower CR and high boost because there is a much larger margin for error than there is with high Static CR. But you will lack the efficiency and the HP on low boost.
It's not a question of what's easier, it's a question of what's feasible. I consider the Turbo F1 era to be the pinnacle of turbocharged engine technology. Do you think they ran high compression or low compression?

I've ran 28psi on a 7.8:1 compression engine on gasoline. Try running 28psi on an 11:1 compression engine and get back to me.
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Old 10-03-2008, 09:49 PM   #147
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Speaking of all this fear about engine knock, anyone here have any experience with Evans Coolant? My N/A experience with this stuff would support the idea that this could really help those with this engine configuration.

www.evanscooling.com


(This argument is on the verge of petering, I thought it a good time to offer this possible 'cure' against knock. If the group disagrees, feel free to delete this post and I will start a thread on it instead)
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Old 10-03-2008, 10:20 PM   #148
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Quote:
Originally Posted by fahrvergnugen View Post
Speaking of all this fear about engine knock, anyone here have any experience with Evans Coolant? My N/A experience with this stuff would support the idea that this could really help those with this engine configuration.

www.evanscooling.com


(This argument is on the verge of petering, I thought it a good time to offer this possible 'cure' against knock. If the group disagrees, feel free to delete this post and I will start a thread on it instead)
If you look at the MSDS sheet on their web site it is just 99% propylene glycol with a little bit of water and a rust inhibitor. Nothing new.
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Old 10-03-2008, 10:34 PM   #149
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I don't believe I offered it as something 'new', only as something that would help cure problems with knock...

Quote:
Historically, racing cars have utilized NPG coolant to effectively thermally manage their engine running with up to a 16.5 to 1 compression ratio.
http://www.evanscooling.com/main21.htm

Apologies for their website in advance, it really sucks navigating.

Last edited by fahrvergnugen; 10-03-2008 at 10:47 PM.
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Old 10-04-2008, 12:12 AM   #150
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Quote:
Originally Posted by JKav View Post
It does.
Shhh...wait for his source to tell him the same thing.

Quote:
Originally Posted by jwarriner View Post
It's not a question of what's easier, it's a question of what's feasible. I consider the Turbo F1 era to be the pinnacle of turbocharged engine technology. Do you think they ran high compression or low compression?

I've ran 28psi on a 7.8:1 compression engine on gasoline. Try running 28psi on an 11:1 compression engine and get back to me.
Ah...let me guess, 6-bolt 4G63? Stock turbo? If stock turbo, you could have gotten away with 9:1 and made more power, had more low-end power, and spool faster. But, of course, this hasn't been proven to be true in this thread yet, so it's speculation.

Quote:
Originally Posted by fahrvergnugen View Post
Speaking of all this fear about engine knock, anyone here have any experience with Evans Coolant? My N/A experience with this stuff would support the idea that this could really help those with this engine configuration.

www.evanscooling.com


(This argument is on the verge of petering, I thought it a good time to offer this possible 'cure' against knock. If the group disagrees, feel free to delete this post and I will start a thread on it instead)
A few people at MSR used it. It eats aluminum heads. So I would not advise using it.
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Old 10-04-2008, 12:59 AM   #151
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Quote:
Originally Posted by ray_sir_6 View Post
Shhh...wait for his source to tell him the same thing.
You're being a pompous ***, acting like you knew knew about c/r and the effect on VE. If you look at post #39 on page 2, I was the one that said

Quote:
Originally Posted by JasonC SBB View Post
I have a theory as to one advantage that high c/r has that I have not seen in a reference. It will have *slightly* higher VE because the clearance volume (c.c. volume at TDC) is smaller and thus:
a) leaves a smaller amount of dead exhaust gas in the cylinder and
b) the initial "suction" on the downstroke is stronger leading to more suckage of intake charge / more initial velocity.

(a) may be extra significant with high exhaust backpressure i.e. turbo.

This may be responsible for some of the gains people see with higher c/r. Plus maybe the piston tops of hi perf hi c/r aftermarket pistons make for better flow and thus VE than factory pistons which are designed for emissions too.
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Old 10-04-2008, 01:12 AM   #152
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Quote:
Originally Posted by patsmx5 View Post
I'm not wrong. I'm not in a hole. BSFC is not LIMITED to .5-.6. It's just a number. .5-.6 may be TYPICAL, but it's not the only range of values. If you read said "source" you'll see it says "general values".

If you reread my post on BSFC, you'll see I said the initial value .5 was ARBITRARY. Do you see that? Do you know what it means? I'll explain. It means it doesn't matter. It's simply a point that I choose for illustrative purposes. It could be more or less, but I picked .5 to ILLUSTRATE THAT YOUR PREVIOUS MATH WAS WRONG. Based on my initial numbers, my formulas are correct. I could have used .5 and .55 or .6 and .55 or whatever the hell I wanted. I was showing you how to use a formula you could not figure out how to use. The end. I was not wrong. Stop saying I was.
Quote:
Brake Specific Fuel Consumption (BSFC). BSFC describes the fuel flow rate required to generate each horsepower. General values of BSFC for turbocharged gasoline engines range from 0.50 to 0.60 and higher.
Lower BSFC means that the engine requires less fuel to generate a given horsepower. Race fuels and aggressive tuning are required to reach the low end of the BSFC range described above.
So I guess you want to compare cars using 120octane race gas? It's only what they said was required to run in the lower range they provided. It said it good be more, but certainly mentioned the EXTREMES you would have to go to get to even .5, yet you want to try using .4**?

Let's try this again. I did it on spreadsheet so everyone can see everything.

Quote:
HP A/F BSFC
350 11 0.55

WA 35.29166667

WA R TM VE VD N
35.29166667 639.6 106 0.96 97.632 7500

12776063.3 / 351475.2

MAP 36.34982867


HP A/F BSFC
350 11 0.54

WA 34.65

WA R TM VE VD N
34.65 639.6 106 0.96 97.632 7500

12543771.24 / 351475.2

MAP 35.68892269

Difference 0.660905976
All I changed was the BSFC from .55 to .54, I didn't even change the VE. Using .54 as the BSFC for the HC motor, you give me the CORRECT BSFC for an engine 12% less efficient. I'll plug it in, and we can all compare.

Quote:
HP A/F BSFC
350 11 0.55

WA 35.29166667

WA R TM VE VD N
35.29166667 639.6 106 0.96 97.632 7500

12776063.3 / 351475.2

MAP 36.34982867


HP A/F BSFC
350 11 0.55

WA 35.29166667

WA R TM VE VD N
35.29166667 639.6 106 0.97 97.632 7500

12776063.3 / 355136.4

MAP 35.97508816

Difference 0.374740502
I only changed the VE from .96 to .97. With the .97 being the HC engine, you give me the CORRECT VE for an engine 12% less efficient. I'll plug it in, and we can all compare.

Now for the formula with both changes

Quote:
HP A/F BSFC
350 11 0.55

WA 35.29166667

WA R TM VE VD N
35.29166667 639.6 106 0.97 97.632 7500

12776063.3 / 355136.4

MAP 35.97508816


HP A/F BSFC
350 11 0.56

WA 35.93333333

WA R TM VE VD N
35.93333333 639.6 106 0.96 97.632 7500

13008355.36 / 351475.2

MAP 37.01073464

Difference 1.035646477
Obivously these are just examples since I need you to give me your numbers for the 12% less efficient LC engine. As soon as I get the correct VE and BSFC for the LC engine from your own math, I'll put them in and we can see the difference.

I'm awaiting your numbers.

Thanks.
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Old 10-04-2008, 01:15 AM   #153
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Originally Posted by ray_sir_6 View Post
A few people at MSR used it. It eats aluminum heads. So I would not advise using it.

Do you have any proof for this?


I've used it for more than five years with -no- wear to the head (several 4-cylinder VWs). What's more, a mechanic friend who has used it for the same period of time has converted at least 20 cars/trucks/vans to it, again with no wear to the head and no other adverse affects. In fact, it is one of his favorite mods to do to the VW Vanagon. They had a wet-sleeve design, in that the steel piston sleeve is bathed in coolant, and it seals to the aluminum head by way of an 0-ring. Vanagons have a nasty history of corroding at this point what with the dissimilar metals only slightly separated. With evans, not only has there been no cooling failures, there is no increase in corrosion since there is no longer any water to cause it.
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Old 10-04-2008, 01:15 AM   #154
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Quote:
Originally Posted by JasonC SBB View Post
You're being a pompous ***, acting like you knew knew about c/r and the effect on VE.
I did know. And I see you did, too. If I remember correctly, you are the one who came up with the 12% rule I am using. Consider that a compliment that I use your numbers.
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Old 10-04-2008, 09:37 AM   #155
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Originally Posted by ray_sir_6 View Post
I did know. And I see you did, too. If I remember correctly, you are the one who came up with the 12% rule I am using. Consider that a compliment that I use your numbers.
actually, KISS came up with 12% first.
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Old 10-04-2008, 07:56 PM   #156
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Originally Posted by ray_sir_6 View Post
Ah...let me guess, 6-bolt 4G63? Stock turbo? If stock turbo, you could have gotten away with 9:1 and made more power, had more low-end power, and spool faster. But, of course, this hasn't been proven to be true in this thread yet, so it's speculation.
Not stock turbo.
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Old 10-04-2008, 10:37 PM   #157
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Originally Posted by fahrvergnugen View Post
I don't believe I offered it as something 'new', only as something that would help cure problems with knock...
The point is, that if one wants to try it out, then all one has to do is go buy some propylene glycol antifreeze (pet safe, enviro friendly, whatever) at the auto parts store and use it undiluted. You do not have to buy their stuff which is overpriced at $30+ a gallon.
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Old 10-04-2008, 10:39 PM   #158
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Originally Posted by jwarriner View Post

I've ran 28psi on a 7.8:1 compression engine on gasoline. Try running 28psi on an 11:1 compression engine and get back to me.
Um, Ok. What would you like to hear? That all you need is the right tune and high octane fuel? Cuz that's all it takes on hard parts that will handle it.
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Old 10-05-2008, 12:09 AM   #159
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Originally Posted by ZX-Tex View Post
The point is, that if one wants to try it out, then all one has to do is go buy some propylene glycol antifreeze (pet safe, enviro friendly, whatever) at the auto parts store and use it undiluted. You do not have to buy their stuff which is overpriced at $30+ a gallon.

Evans is the only coolant on the market that is 100% PG; they are also the engineers of using it in a cooling system. To me, that is good insurance. That, and I can't find any source for pure PG anywhere else.

It's expensive sure, but if it is pure it will be a lifetime coolant.


Back to the point of my post; I believe this will help inhibit knock. Does no one here use this in their Miata, or will I be the first?
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Old 10-05-2008, 12:49 AM   #160
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Originally Posted by ZX-Tex View Post
The point is, that if one wants to try it out, then all one has to do is go buy some propylene glycol antifreeze (pet safe, enviro friendly, whatever) at the auto parts store and use it undiluted. You do not have to buy their stuff which is overpriced at $30+ a gallon.
I've thought about this, but then why does their newer NPG-R have a lower viscosity than their older NPG? The NPG has lower viscosity than Sierra (cheaper PG) antifreeze too... IIRC Sierra is meant to be run with water, Evans isn't.
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