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-   -   high compression e85 turbo bp? (https://www.miataturbo.net/engine-performance-56/high-compression-e85-turbo-bp-72064/)

concealer404 Apr 17, 2013 10:35 AM


Originally Posted by Tork (Post 1001998)
Scratching my head here guy because this is what I'm saying. Then you sayI'm wrong. But then you agree with me on what i was arguing..?

Because it's "BASIC principles."

That's the golden rule of thumb or whatever the fuck.

Then you tweak the rule to apply it to each different engine.

Is this really this complicated?

18psi Apr 17, 2013 10:37 AM


Originally Posted by Tork (Post 1001998)
Scratching my head here guy because this is what I'm saying. Then you sayI'm wrong. But then you agree with me on what i was arguing..?

Except there is WAYY more to it than that.
Because "that" is a drastic over-generalization and what n00bs throw out when they have no idea about a specific engine design and try to apply their general "knowledge" of how an internal combustion engine works to a specific one.

If you really think different 4 cylinder engines, used in different applications, make power the same way, you need to just stop posting.

So I ask you again, how many high powered BP's have you built? I'll make it even easier for you: how many have you built or tuned over a measly 200whp?



Originally Posted by concealer404 (Post 1002000)
Because it's "BASIC principles."

That's the golden rule of thumb or whatever the fuck.

Then you tweak the rule to apply it to each different engine.

Is this really this complicated?

*edit: beat me to it

He's trying so hard to be smart that he's in denial about being dumb. You can't skip the painful step of acknowledgement :giggle:

Ryan_G Apr 17, 2013 10:40 AM


Originally Posted by Tork (Post 1001998)
Scratching my head here guy because this is what I'm saying. Then you sayI'm wrong. But then you agree with me on what i was arguing..?

I love how you cherry picked one statement out of context in order to make yourself not look like an idiot.

What if I told you.... that we see through the bullshit. As others have said already, Timing > Compression on our motors. We have found that ~8.6:1 is about the ratio you need for pump gas to get the maximum benefits of timing before reaching det. So in short, while using pump gas, lower compression will net you better numbers until you hit this threshold on our motors.

Leafy Apr 17, 2013 10:46 AM


Originally Posted by Tork (Post 1001917)
How is our bp "engine" (not motor),

This, this right here makes me believe that Tork is one of those FSAE kids from a school where the alumni design a crazy carbon monocoque car with super duper aero, and the school has paid machine shop workers build the car because the students arent allowed to touch the machines. And then they get coached on what to say in design by those alumni, because one of the things drilled in during that coaching is the car has an Engine in is, motors move your windshield wipers. :vash: Hey if the SAE is such a stickler about calling it an engine why do I fill it with SAE5w20 MOTOR oil.

miata2fast Apr 17, 2013 11:43 AM


Originally Posted by miata2fast (Post 999112)
If that kind of time and expense is in your budget, then it is a viable option. If not, stick with the tamer compression.

Keep in mind that high compression big camshaft motors are volatile, and do not take kindly to tuning mistakes. If you lack experience, I would suggest sticking with a tamer motor, and as you build experience work your way up to the big boy stuff.


Originally Posted by mspdmx3 (Post 999594)
Well I'm pretty experienced with tuning/building the bp I just wanted to see if anyone had concrete info on 400whp + e85 setups. My last setups made 300+ whp on hydraulic bp05 head and high boost so I expect a lot more power now. So what do you guys think about the cylinder pressures on low comp high boost (30lbs) e85 vs med comp high boost e85(30lbs). I doubt less power and better off boost transient response, but what about head lifting, etc? Thanks

It takes us a while to know if someone has been around the block or is just blowing smoke.

Anyways, it looks like you have enough know how to go into unfamiliar territory. Do it. I would love to see more really big horsepower BPs.

BPs are not really known for head gasket issues. Eventually you will get to a point that you may need to address head lifting, but you will have to be well past the 400 hp mark. There are enough well past 500 that did not need any exotic modifications to prevent lifting, as far as I know.

Savington Apr 17, 2013 12:11 PM


Originally Posted by Tork (Post 1001909)
Congrats.. For what shop? You didn't answer my question either. Inn your theory less boost makes more power..? In that what you're trying to tell me? Yes or no?

Compression isn't boost. Don't put words in my mouth.

With the BP, the timing you give up to run higher compression is worth more than the power you gain back from the compression itself. It's better to have the timing than the compression. It's very simple.

turbofan Apr 17, 2013 12:12 PM

Thanks for the clarification on my motor Vlad.

I think the issue here is that the locals are being more specific than Tork, but tork thinks he's being more specific. Tork is talking about basic principles, while savington and crew are describing how to apply those basic principles to our tuning challenge.

Tork , NOBODY here is saying to take a BP setup running a stock block and 2560 at 14 psi and drop the compression to make more power without any other changes. You drop compression in order to increase boost and make timing more aggressive. In fact, even this is not BP specific: this has been basic big-power S.O.P for gasoline for ages. Drop compression to 8.5:1 or so, increase boost and advance timing, profit. E85 changes that a bit due to its anti-knock properties.

Quit taking one phrase and blanketing it. You don't appear smart. Get out of your box and quit being so damned pig headed.

Savington Apr 17, 2013 12:14 PM


Originally Posted by turbofan (Post 1002063)
Tork , NOBODY here is saying to take a BP setup running a stock block and 2560 at 14 psi and drop the compression to make more power without any other changes. You drop compression in order to increase boost and make timing more aggressive. In fact, even this is not BP specific: this has been basic big-power S.O.P for gasoline for ages. Drop compression to 8.5:1 or so, increase boost and advance timing, profit. E85 changes that a bit due to its anti-knock properties.

Quit taking one phrase and blanketing it. You don't appear smart. Get out of your. Six and quit being so damned pig headed.

On a BP, you don't even need to add boost. You can drop compression a bit and add timing and you'll find additional power and torque.

TurboTim Apr 17, 2013 12:15 PM


Originally Posted by Savington (Post 1002060)
Compression isn't boost. Don't put words in my mouth.

With the BP, the timing you give up to run higher compression is worth more than the power you gain back from the compression itself. It's better to have the timing than the compression. It's very simple.

it's not simple to Tork. he has no idea what MBT is.

GAMO Apr 17, 2013 01:27 PM

Tork is battin' 1000.

ExpertInNothing Apr 17, 2013 01:48 PM

You guys cannot actually be serious. So your telling me that if I were to boost my 1.8L I should lower my compression...which in turn would do absolutely nothing because there would be no "overfilling of the combustion chamber" to create power? Well for all that I might as well run N/A...but running N/A is pointless because I would still run low compression...hence not making any type of power...I mean so far from this thread thats what I have learned...low compression=power...am i correct?

GAMO Apr 17, 2013 01:51 PM

Parachute account found.

18psi Apr 17, 2013 01:52 PM


Originally Posted by ExpertInNothing (Post 1002157)
You guys cannot actually be serious. So your telling me that if I were to boost my 1.8L I should lower my compression...which in turn would do absolutely nothing because there would be no "overfilling of the combustion chamber" to create power? Well for all that I might as well run N/A...but running N/A is pointless because I would still run low compression...hence not making any type of power...I mean so far from this thread thats what I have learned...low compression=power...am i correct?

You are either:

same idiot as Tork using different sign on
his idiot friend
???

I'm leaning towards 1 and 2.

18psi Apr 17, 2013 01:53 PM


Originally Posted by GAMO (Post 1002162)
Parachute account found.

ban fist is getting polished up to thrust into his anus soon

concealer404 Apr 17, 2013 01:54 PM


Originally Posted by ExpertInNothing (Post 1002157)
You guys cannot actually be serious. So your telling me that if I were to boost my 1.8L I should lower my compression...which in turn would do absolutely nothing because there would be no "overfilling of the combustion chamber" to create power? Well for all that I might as well run N/A...but running N/A is pointless because I would still run low compression...hence not making any type of power...I mean so far from this thread thats what I have learned...low compression=power...am i correct?

You've got to be kidding me. I've been further even more decided to use even go need to do look more as anyone can. Can you really be far even as decided half as much to use go wish for that? My guess is that when one really been far even as decided once to use even go want, it is then that he has really been far even as decided to use even go want to do look more like. It's just common sense.

18psi Apr 17, 2013 01:58 PM


Originally Posted by concealer404 (Post 1002170)
You've got to be kidding me. I've been further even more decided to use even go need to do look more as anyone can. Can you really be far even as decided half as much to use go wish for that? My guess is that when one really been far even as decided once to use even go want, it is then that he has really been far even as decided to use even go want to do look more like. It's just common sense.

:bowrofl:

Flawless logic

+Props

ExpertInNothing Apr 17, 2013 02:01 PM


Originally Posted by 18psi (Post 1002167)
ban fist is getting polished up to thrust into his anus soon

ok before you ban me or whatever it is you people do to guys who know what they are talking about, answer me something. simple question really...when has lowering compression ever made sense when we are talking about making power. I want as much "bang" in that cylinder as possible...and high compression and a good amount of boost will do so...please explain to me how low compression will have the same effect...because in my mind low compression and power do not mix.

concealer404 Apr 17, 2013 02:05 PM


Originally Posted by ExpertInNothing (Post 1002186)
ok before you ban me or whatever it is you people do to guys who know what they are talking about, answer me something. simple question really...when has lowering compression ever made sense when we are talking about making power. I want as much "bang" in that cylinder as possible...and high compression and a good amount of boost will do so...please explain to me how low compression will have the same effect...because in my mind low compression and power do not mix.

The logic is correct.


That is, if you ignore that other thing that makes motors run.

That being... you know... ignition.

Ryan_G Apr 17, 2013 02:06 PM


Originally Posted by ExpertInNothing (Post 1002186)
ok before you ban me or whatever it is you people do to guys who know what they are talking about, answer me something. simple question really...when has lowering compression ever made sense when we are talking about making power. I want as much "bang" in that cylinder as possible...and high compression and a good amount of boost will do so...please explain to me how low compression will have the same effect...because in my mind low compression and power do not mix.

If you would scroll up it has already been explained multiple times on this very page.

ExpertInNothing Apr 17, 2013 02:08 PM


Originally Posted by concealer404 (Post 1002188)
The logic is correct.


That is, if you ignore that other thing that makes motors run.

That being... you know... ignition.

ok valid, so we overfill the cylinder...time our spark at precise degree of timing and things will make ample amount of power correct? too low of compression and no matter when you spark things, it wont make any power because there was never a good enough squeeze to begin with.


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