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Engine tips needed!

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ArtyomRanger

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Post Fri Feb 19, 2016 7:10 am

Engine tips needed!

Hello everyone, i need a bit of help :)

I have a bit problem with my non turbo engines, the problem is they are redlining to get all horsepower so how do i change it to make my power available at lower rpms ?

and the last question is for the turbo engines, i do know if i want more torque or my power at lower rpms i change the size of turbine or the compressor, but since i'am such a noob they are not gonna survive for long so i need some help here too

Thanks for reading
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Forum thread: viewtopic.php?f=34&t=9506
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squidhead

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Post Fri Feb 19, 2016 7:12 am

Re: Engine tips needed!

N/A engines - to get the peak power earlier you need to go less aggressive on the camshaft.
Turbo engines - That's the tradeoff if you want to have a very low rev boost - the small turbo will start restricting airflow in the higher RPM.
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ArtyomRanger

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Post Fri Feb 19, 2016 7:16 am

Re: Engine tips needed!

squidhead wrote:N/A engines - to get the peak power earlier you need to go less aggressive on the camshaft.
Turbo engines - That's the tradeoff if you want to have a very low rev boost - the small turbo will start restricting airflow in the higher RPM.



Okay Thanks, is there a way to get low rev boost, with a bigger turbo ?
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Forum thread: viewtopic.php?f=34&t=9506
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squidhead

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Post Fri Feb 19, 2016 8:06 am

Re: Engine tips needed!

No, not really. Big turbo needs a lot of exhaust flow to produce boost, and that happens at higher RPM's. If you want your engine not to be useless at low revs - make it bigger, so it can give you some torque on its own, before the turbo starts kicking in.
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ArtyomRanger

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Post Fri Feb 19, 2016 8:09 am

Re: Engine tips needed!

squidhead wrote:No, not really. Big turbo needs a lot of exhaust flow to produce boost, and that happens at higher RPM's. If you want your engine not to be useless at low revs - make it bigger, so it can give you some torque on its own, before the turbo starts kicking in.


Alright thanks for the help ^^
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Forum thread: viewtopic.php?f=34&t=9506
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TurboJ

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Post Sat Feb 20, 2016 1:35 am

Re: Engine tips needed!

With turbo engines you should always make sure you have the compressor and turbine showing as RED on your engine component diagnostics screen.
Contrary to other components you want the turbo to actually "reduce" maximum output because if you have a perfectly flowing turbo (no restrictions) your turbo will spool up really late.
So, use smaller compressor and turbine - go as small as you can while still making your desired power.

About boost pressure: You can naturally get more power with more boost, but in reality you should push your compression ratio up and run a little less boost -> this will make your engine more efficient.
Only lower compression ratio if you have no other choice. For example, with 2015 technology you can make 200 horsepower per litre with 9.4:1 compression ratio if you tune your engine right.

About low-down power: this is a combination of three things:

1. Cam timing - turbo engines should always have less aggressive cams than a sporty N/A engine.
2. Turbo sizing - always go as small as you can. Ideal results come with using a larger compressor and smaller turbine.
3. Compression ratio - the higher compression, the more torque you will have without boost. So learn to tune the engine well so you can run higher compression ratios.
(4). Fine tuning cam profile and turbo sizing together -> goal is to have these optimized together so your power delivery will be smooth and fuel efficiency will be high
Last edited by TurboJ on Sat Feb 20, 2016 2:02 am, edited 1 time in total.
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ArtyomRanger

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Post Sat Feb 20, 2016 1:39 am

Re: Engine tips needed!

TurboJ wrote:With turbo engines you should always make sure you have the compressor and turbine showing as RED on your engine component diagnostics screen.
Contrary to other components you want the turbo to actually "reduce" maximum output because if you have a perfectly flowing turbo (no restrictions) your turbo will spool up really late.
So, use smaller compressor and turbine - go as small as you can while still making your desired power.

About boost pressure: You can naturally get more power with more boost, but in reality you should push your compression ratio up and run a little less boost -> this will make your engine more efficient.
Only lower compression ratio if you have no other choice. For example, with 2015 technology you can make 200 horsepower per litre with 9.4:1 compression ratio if you tune your engine right.

About low-down power: this is a combination of three things:

1. Cam timing - turbo engines should always have less aggressive cams than a sporty N/A engine.
2. Turbo sizing - always go as small as you can. Ideal results come with using a larger compressor and smaller turbine.
3. Compression ratio - the higher compression, the more torque you will have without boost. So learn to tune the engine well so you can run higher compression ratios.
4. Fine tuning cam profile and turbo sizing together -> goal is to have these optimized together so your power delivery will be smooth and fuel efficiency will be high


Awesome, thanks
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Forum thread: viewtopic.php?f=34&t=9506
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TurboJ

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Post Sat Feb 20, 2016 2:06 am

Re: Engine tips needed!

ArtyomRanger wrote:Awesome, thanks


No problem mate! Just let us know if you're having more issues and you will find help right here :)
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J.S.C Automobili S.p.A - Exclusive sports cars since 1959
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Sillyworld

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Post Mon Feb 22, 2016 1:20 pm

Re: Engine tips needed!

This:
TurboJ wrote:1. Cam timing - turbo engines should always have less aggressive cams than a sporty N/A engine.
2. Turbo sizing - always go as small as you can. Ideal results come with using a larger compressor and smaller turbine.
3. Compression ratio - the higher compression, the more torque you will have without boost. So learn to tune the engine well so you can run higher compression ratios.
(4). Fine tuning cam profile and turbo sizing together -> goal is to have these optimized together so your power delivery will be smooth and fuel efficiency will be high

Listen to this man, I mean, even its username says turbo :lol:

What I do, is I choose a boost first (5-7 psi for efficiency, 8-10 psi for regular sports cars, 10-12 when I only want POWAHH) the higher the boost the lower the reliability, keep that in mind. For the A/R ratio, I use around 0.5 for spooling really early, usually .64 for regular engines (spooling around 3,000 rpms) or .84 for more high-end power. Then I adjust the size, for the compressor I go as low as I can without loosing power, and the turbine as larger as I can, until I loose power. Alternativaly, sometimes I use a A/R ratio of 1 or higher and use a large compressor and a small turbine. This combination usually gives more power but I prefer the other one as I tend to make more efficient engines that way (with better throttle response). Don't forget to play with the cam profile to get the most power, or the flatter torque curve, or whatever you're looking for. Don't be afraid to add 1 or 2 quality points at the turbo or the fuel system if you get engine knoc, that way you don't have to reduce the compression ratio.
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ArtyomRanger

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Post Mon Feb 22, 2016 10:13 pm

Re: Engine tips needed!

Sillyworld wrote:This:
TurboJ wrote:1. Cam timing - turbo engines should always have less aggressive cams than a sporty N/A engine.
2. Turbo sizing - always go as small as you can. Ideal results come with using a larger compressor and smaller turbine.
3. Compression ratio - the higher compression, the more torque you will have without boost. So learn to tune the engine well so you can run higher compression ratios.
(4). Fine tuning cam profile and turbo sizing together -> goal is to have these optimized together so your power delivery will be smooth and fuel efficiency will be high

Listen to this man, I mean, even its username says turbo :lol:

What I do, is I choose a boost first (5-7 psi for efficiency, 8-10 psi for regular sports cars, 10-12 when I only want POWAHH) the higher the boost the lower the reliability, keep that in mind. For the A/R ratio, I use around 0.5 for spooling really early, usually .64 for regular engines (spooling around 3,000 rpms) or .84 for more high-end power. Then I adjust the size, for the compressor I go as low as I can without loosing power, and the turbine as larger as I can, until I loose power. Alternativaly, sometimes I use a A/R ratio of 1 or higher and use a large compressor and a small turbine. This combination usually gives more power but I prefer the other one as I tend to make more efficient engines that way (with better throttle response). Don't forget to play with the cam profile to get the most power, or the flatter torque curve, or whatever you're looking for. Don't be afraid to add 1 or 2 quality points at the turbo or the fuel system if you get engine knoc, that way you don't have to reduce the compression ratio.



Thanks, this will help me even more :D

Now i need POOOWWWAAAHHH
Car Company: AmeroMotors
Forum thread: viewtopic.php?f=34&t=9506
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TurboJ

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Post Wed Feb 24, 2016 3:11 am

Re: Engine tips needed!

OP,

If you're interested in seeing some optimized high-performance turbo engines you can download some of mine here:

viewtopic.php?f=34&t=9311

...You may see something there to give you ideas you could later try on your designs. These engines are tuned for
wide power register and good fuel economy but there's still a decent power-to-weight-to-price ratio.
Image

J.S.C Automobili S.p.A - Exclusive sports cars since 1959
J.S.C Motori Speciali - My open-source performance engines
Patriot Motor Force - 'Murican Evolutionary muscle cars

My Engine Tuning Video Guides
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ArtyomRanger

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Post Wed Feb 24, 2016 3:31 am

Re: Engine tips needed!

TurboJ wrote:OP,

If you're interested in seeing some optimized high-performance turbo engines you can download some of mine here:

viewtopic.php?f=34&t=9311

...You may see something there to give you ideas you could later try on your designs. These engines are tuned for
wide power register and good fuel economy but there's still a decent power-to-weight-to-price ratio.


Thank you i appreciate your help, i will definitely give it a look :)
Car Company: AmeroMotors
Forum thread: viewtopic.php?f=34&t=9506
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SheikhMansour

Posts: 16

Joined: Wed Jan 13, 2016 6:05 pm

Post Thu Feb 25, 2016 12:01 am

Re: Engine tips needed!

Sillyworld wrote:
What I do, is I choose a boost first (5-7 psi for efficiency, 8-10 psi for regular sports cars, 10-12 when I only want POWAHH) the higher the boost the lower the reliability, keep that in mind. For the A/R ratio, I use around 0.5 for spooling really early, usually .64 for regular engines (spooling around 3,000 rpms) or .84 for more high-end power. Then I adjust the size, for the compressor I go as low as I can without loosing power, and the turbine as larger as I can, until I loose power. Alternativaly, sometimes I use a A/R ratio of 1 or higher and use a large compressor and a small turbine. This combination usually gives more power but I prefer the other one as I tend to make more efficient engines that way (with better throttle response). Don't forget to play with the cam profile to get the most power, or the flatter torque curve, or whatever you're looking for. Don't be afraid to add 1 or 2 quality points at the turbo or the fuel system if you get engine knoc, that way you don't have to reduce the compression ratio.


Those boost pressures seem really low, especially for your power applications. This article (http://autoweek.com/article/car-news/ne ... -laid-bare) quotes the boost pressure of the M3/M4 at 18.9psi (...the IHI units provide a relatively conservative maximum boost pressure of just 18.9 psi.), although Car and Driver (http://www.caranddriver.com/features/di ... m4-feature) quotes 18.1psi. If you're looking for pure power, 12 psi seems quite low unless you're using small-ish turbos and trying to get lower end power as well, although the Mercedes M275/M279 engines (https://en.wikipedia.org/wiki/Mercedes-Benz_M275_engine) have 22.1psi and still produce 1000Nm (738lb*ft) of torque. Do you have a reason for only using 12psi in your power applications?
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squidhead

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Post Thu Feb 25, 2016 1:03 am

Re: Engine tips needed!

The power is not equivalent to boost, also the more boost you get the less usable engine you receive, not to mention the awful fuel consumption
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TurboJ

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Post Thu Feb 25, 2016 1:08 am

Re: Engine tips needed!

There are certain differences in how turbos work on this game and in modern real-life turbo engines. The turbo tech in the game is based on '80s tech and it will be overhauled in the future to include modern-day systems.
Only very lately real-life cars have begun using such high boost pressures. 10 years ago only special versions of Evos and such had 1.5 bar boost pressures. So as long as the game uses old turbo tech, you need to take that
into account. High pressures like today would cause intolerable heat loads with '80s compressors. In-game you will notice that there are certain limits within which your boost pressure increases have a positive effect to power;
after that certain limit you will run out of the efficiency map so to speak.

In the game, you need to use relatively high compression ratios for road engines, because otherwise you will lose a lot of fuel efficiency and responsiveness. You adjust your power more by turbo sizing and less by turbo pressure.
For optimal results you will use slightly larger compressors with smaller turbines. For very sporty engines you need high A/Rs and lower for eco-engines. Furthermore, with a small turbo you need MORE boost pressure for a given
horsepower amount. Air flow and boost pressure are not linearly connected. The larger the compressor, the lower the required boost pressure for the same amount of air flow.

For direct fuel injection you can use 10:0 compression ratio to begin with; you will then reach 110-120 hp per litre or more with boost pressures of 0.55-0.75 bar. (This is an estimate, I can't login to Automation right now.)
For a supercar engine you can go down to 9:1 CR - any lower than that won't really be good as you will have low efficiency and response. For Non-direct injection ballpark is 8 - 9 CR.

One thing I have noticed is the game doesn't represent non-intercooled turbo engines very well. IRL Lotus Esprit Turbo and Maserati Biturbo had 90+ horsepower per litre in 1981 without intercooling and even used carburettors
for fuel, yet were reasonably economical. In the game you will need very rich mixtures or very low compression ratios if you run without an intercooler.

Other than that the in-game engine designer is GREAT. It's amazing really how close to real world engines you can get. It's only forced-induction little details that need polishing.
Image

J.S.C Automobili S.p.A - Exclusive sports cars since 1959
J.S.C Motori Speciali - My open-source performance engines
Patriot Motor Force - 'Murican Evolutionary muscle cars

My Engine Tuning Video Guides
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