Time to go Stage II!

[Alky V6]

While we're waiting for more progress on the intake, I thought I'd throw in some food for thought.
This is the compressor map for a Borg Warner Airwerks S510 turbocharger. The red line through the map signifies the operating line for the old Stage I setup. The hp at low boost was confirmed through low boost time slips. Really, you couldn't have asked for much better.

 

[Alky V6]

This is a conservative guess of what the operating line for the Stage II project will look like with the s510 compressor map.
A bit of a more leveled out slope, starting at a lower power level at the lower boost numbers due to the heads and cam, ending at a PR of 3.82 (41 psi boost) and 1,450 bhp.
About 69% compressor efficiency on the top end, and 75% eff at 2.0 PR.

 

[Alky V6]

Or, maybe the operating line will take on more of a curve such as in this example.

 

[Alky V6]

Or, maybe it will look like this. I do expect more hp at 28 psi boost than what I had with the Stage I project.
This curve starts to take on the characteristics of an S curve. You could make minor changes to this curve to adjust the hp level for certain PR values, but still the curve will end up traveling through highly preferred compressor efficiency zones throughout much of the curve. This is exactly what attracted me to this particular turbo in the first place.

 

[Alky V6]

Can anyone see just a little bit of room to move up to a larger turbo? Those compressor maps are to a s510 turbo which comes standard with a 95mm comp wheel. Maybe a 98mm?

 

[turbojosh]

Can anyone see just a little bit of room to move up to a larger turbo? Those compressor maps are to a s510 turbo which comes standard with a 95mm comp wheel. Maybe a 98mm?

Wtf! Your crazy Donnie! That thing is moving like a Wizard of Oz tornado! I dunno man, maybe . I'm going to look at this more. Thing is pushing like prego women thou.

 

[turbojosh]

Thats huge from the stage I set up ! Wow . That red line is an awesome marker for refrence point.

 

[Alky V6]

This is an interesting comparison.
The purple line was charted using real world Stage I performance.
The green line was the estimation that the sim came up with for the Stage I project using modifed head flow numbers to better match real world results.
The red line is a conservative estimation that the sim came up with for the Stage II project using real world head flow numbers.
I'm real curious to see what the real world Stage II operating line will look like.

 

[Alky V6]

The max effort camshaft and lifters have arrived. I'm going to degree out the cam so I can see what sort of ramps I have.

Time to send the block out to be bored. Then, I can figure out the pistons to order.
Hmmm. I wonder what compression ratio I should go with.

 

[turbobitt]

Since your looking for guidance, give us your detailed cam specs, seperation angle, and installed centerline so we know what the cylinder is doing.

Allan G.

 

[Reggie West]

The max effort camshaft and lifters have arrived. I'm going to degree out the cam so I can see what sort of ramps I have.

Time to send the block out to be bored. Then, I can figure out the pistons to order.
Hmmm. I wonder what compression ratio I should go with.

How about 12 to 1 so you can finally max out that turbo you have?

 

[Alky V6]

Since your looking for guidance, give us your detailed cam specs, seperation angle, and installed centerline so we know what the cylinder is doing.

Allan G.

Oh, you are a tricky one.

 

[Alky V6]

How about 12 to 1 so you can finally max out that turbo you have?

Actually, Reggie, if the plan is to increase boost, you would want to lower static CR. Not increase it.
If off idle performance was the only concern, then 12:1 would be a good choice.

 

[TurboDave]

Can you run 10:1? I would think the Meth would have a huge cooling effect on the combustion chamber! I'm learning how important that is..... I know this is totally unrelated, but.... Since I've been driving this twin turbo ecoboost motor, I'm learning how important combustion chamber cooling can be. These motor run two turbos, 12# of boost, 10:1 CR, and all on 87 octane!!! A big factor must be the direct injection, and piston squirters.

 

[norbs]

I think 9.5:1 to is a good choice for him

 

[Alky V6]

Can you run 10:1? I would think the Meth would have a huge cooling effect on the combustion chamber! I'm learning how important that is..... I know this is totally unrelated, but.... Since I've been driving this twin turbo ecoboost motor, I'm learning how important combustion chamber cooling can be. These motor run two turbos, 12# of boost, 10:1 CR, and all on 87 octane!!! A big factor must be the direct injection, and piston squirters.

Direct injection is a whole different ball game.

The plan with my project is to run up to 41 psi boost pressure. 45, if the engine will push the turbo to that level. I would imagine that most understand the difference between 'static compression ratio' and 'dynamic compression ratio'. Depending on the circumstances, too much of either will get you into trouble, no matter what fuel you are running.
By starting with a lower static compression ratio, you can run more boost before you run into a dynamic compression ratio limit for the fueling you are using. The more boost you can run, the denser the intake charge, the more air and fuel you are packing into the cylinder, the more CID increase you are simulating with your particular combination.
Instead of depending on the static CR level to preheat the intake charge, I'm trading some of the job of preheating the charge to the compressor of the turbo when it is operating at the higher boost levels.
The only reason you would want to run more static compression is if you first set a modest boost limit so that you wouldn't surpass the dynamic compression limit of the fueling, and are trying to achieve a better off boost performance. For me, that is not even a consideration. Nitrous oxide injection solves that problem extremely well.

 

[Alky V6]

I think 9.5:1 to is a good choice for him

I'm going to stick with 9.25:1. That is low for methanol, but with my high boost target, should be about right, as far as my dynamic CR limit goes.
I've heard of a few people now running straight methanol that were in the 6s:1 with their static CR, with much higher boost numbers than what I'm planning. Those people settled on the 6s for the static CR for a very good reason. Racing is much cheaper when you can keep the motor from scattering all over the track.
Remember this? It's a well known tuning principle. It's much better, safer, and cheaper to start out low (or richer) and work up (or leaner), rather than starting too far up and having to pay big time again to start a little lower for the next time.
I am investing way too much time and money into this project to take the chance of making the silly mistake of running too much compression. I figure I'll get her running, do my testing, and if I find that the tuneup looks safe even at the 40-45 psi boost level, then I can decide whether or not to move up to a higher compression ratio the next time the engine is down for a PMing. That seems like a much better idea than starting out too high on the CR and scattering an engine. I've gone through that a few times already when I was learning the fuel, and it certainly is not fun.
Another option to raising the static CR would be to figure out how to run more boost. But then, I'd have to figure out how to add more fueling. Arrg. A vicious circle.

 

[Alky V6]

Dynamic compression ratio. That's an interesting topic.
What is the dynamic compression ratio limit for different types of fuel? The initial charge temperature before cylinder compression would have to be taken into consideration.
I'm guessing I'll be touching on around 32:1 at over 40 psi boost.
Does anyone have any links to some calculators to figure out the dynamic compression ratio?

 

[turbobitt]

Dynamic compression ratio. That's an interesting topic.
What is the dynamic compression ratio limit for different types of fuel? The initial charge temperature before cylinder compression would have to be taken into consideration.
I figure I'll be touching on around 32:1 at over 40 psi boost.
Does anyone have any links to some calculators to figure out the dynamic compression ratio?

Your using these terms to loosly. Compression ratio never changes, dynamic or static. Dynamic cylinder pressure changes with a given boost pressure and compression ratio. I made a simple spreedsheet a while back comparing cylinder pressure at different boost levels. The equivelant cylinder pressure at 35# boost on a 9:1 engine would be a 30.5:1 engine normally asperated. These numbers can be decieving since there is no charge cooling effect on a 30.5:1 compression engine vs. a 9:1 engine at 35# boost.
Comp. Boost Pressure
9 40 477.6
9 35 432.6
9 30 387.6
9 20 297.6
9 15 252.6
8 35 382.9
8 30 342.9
8 20 262.9
8 15 222.9
30.5 0 433.65
Allan G.

 

[Alky V6]

I found a calculator online. It shows that my setup at 45 psi boost would have a dynamic CR of 28.55:1.
Here's the link: http://www.wallaceracing.com/dynamic-cr.php

edit: I'm not sure exactly which valve timing figure the Wallace calculator uses. Seat to seat or .050" lift cam timing figures. I used the .050" figure.