[GolGT86]

Your idea was almost my final paper at my mechanical engineering college hahaha. I did a long study on how to put the SC in the engine of my Dodge 1800 Polara (Brazilian Hillman Avenger).
The magnetic pulley can be used via a customized output activated by a TPS load. You can use the WMI outputs as bypass control, including using the WMI advance delay as a way to slow down the SC input, etc., and you can use the VVT ​​as on/off for the pulley.
Boost control remains normal as in a turbo. Unfortunately, I was only able to do the ignition part, with a detailed study on the advantages of using a mapped ignition on an old engine with the good old SU touching fuel, and then the entire fuel part with a manifold made with long runners, etc. SC was left out... My plan A was to use SC + wmi! Then I would just go to SC, but for personal reasons I didn't have time to come up with the original idea for the work!

[huramentzefix]

Dude, use whatever you think will work best, or whatever you like, for any reasons you like. This is not an argument of which blower is awesome or crap - it was(?) a discussion of general points, principles, and perspective to approach your stated goals in different ways that could help in best success. Well, it was for me, anyway.

My story of the Samurai was not a social discussion or "do it this way", but to begin looking at the pros and cons of real-world results of similar projects and goals, and how one or another approach worked well (or not) and why.


That info might be helpful to your project. From this, is there a way to configure your SC to be even more effective with your needed boost profile? I have other projects I have done that are also similar, that could be of interest to you for how they worked better or worse, and could benefit your project success. An LQ3 5.7L low-rpm boosted street truck comes to mind that held a lot of lessons for me.

I don't care what you use, but I hope you succeed. You do not need to be defensive about your favorite stuff, as I discuss on technical points and merits, not which one you like to pet. I would appreciate if you are going to argue instead of discuss, that you get more general facts right, or accept other ways they could work that are not typical. I don't argue what color people like, but I'll discuss what colors might have benefits for a purpose, if you see what I mean. Having done a lot of this stuff for many years, I try to help users help themselves to get to where they are happy, quicker and/or better. Well, that's my intent anyway, and that does not appear to be happening here. Let us know how it goes.

[huramentzefix]

[huramentzefix]

I am after low end torque, I don't want HP.
I appreciate your input and love a good discussion but a turbo is not giving me what I am looking for.
I am after something that makes my car strong so that it pulls my trailer well, I don't want a racecar. I need Nm not kW.

[PSIG]

Do your thing, and I'll leave you to it, but your examples were set up for higher rpm hp, which is not what you're after. The LQ3 I built was into full boost by 1800 rpm, and held boost until it hit choke at 4300. 1800 is only 150 rpm above cold idle on that engine. The boost curve was similar to my graph.

It's how you set them up, which is not how you will find others setting them up, so using references like that will be misleading. I 'm not pushing turbo (I use SCs too), but demonstrating how there are configuration options that may fit your goals you may not be considering by focusing so hard on one option. Good luck with your project.

[EdMcGuirk]

If you look at cars that have superchargers with clutched pulleys, you will see that they also have bypass valves. (like my MR2) The bypass valve does most of the work and the clutch gets the last 5 or 10% of the non boosted efficiency.

The existing bypass valve should open whenever any vacuum is present after the throttle (or when the pressure after the throttle is lower than before the throttle if you are boosting before the throttle). You could add an auxiliary bypass valve to kill boost with wide open throttle (for high RPM) or you could depend on the freewheeling supercharger impellers to induce a vacuum when the clutch is disengaged. (that seems inefficient to me) Either way the bypass valve must open whenever boost is off.

A positive displacement supercharger like the eaton should produce relatively constant boost at all RPM except for very low RPM and very high RPM where the supercharger is naturally inefficient. This should produce a relatively constant torque increase across the rpm range. My MR2 produces exactly 8 PSI of boost from just under 2000 RPM up to around 5000 RPM where boost will begin to fall off unless it is a warm day and the intercooler is failing to cool the intake charge (in that case the boost pressure and boost temperature go up) (although exhaust back pressure also gets reflected back into the intake pressure).

Therefore knock is most likely at low RPM. Danger of engine damage actually goes down as RPM goes up past the engines unboosted torque peak RPM. Or saying it another way, the danger comes from how much you increase the torque, not how much you increase the HP.

[huramentzefix]

https://www.kleinanzeigen.de/s-anzeige/ ... 18-223-646
Mercedes 2710902080 Kompressor Eaton

https://www.kleinanzeigen.de/s-anzeige/ ... 4-223-5224
Mercedes W203 Kompressor

these compressors have a second throttle body. probably the "bypass valve" that is being refered to here?
so I can run a 0.8 bar boost from low rev's and then open the bypass and use the bypass to controll boost pressure?

and whenever there is a vacuum then I have to open that throttle as well all the way?
easy enough!
I can use D-Stage's controller to controll that throttle?
With an arduino and a simple RPM diferrential pressure algorithm?

I was wishing for 8psi (0,5 bar) earlier than 2000 rpm.
0,7 bar at 1300 rpm would be sweet. this then can drop off at 3000 rpm.
Again, this might be strange to some people here but I am not looking for high HP.
What I want is high torque at low rev's.

There was a guy from the UK whose videos I have been watching yesterday. He actually had to install a bypass flap actuated by the throttle cable to bring the noise level down.
I need to investigate what this is about.

https://www.youtube.com/watch?v=JJ9CeJke4sQ
here is the british guy and his project.
please find someone where he reports about the second throttle to reduce noise

https://www.youtube.com/watch?v=etV95iPH3lE
here without bypass in an MX5

I was under the impression tha I could just bolt the supercharger to the car and be a happy chap.
But more and more things are indicating that the bypass throttle body make sense and are actually required.

what is it with the noise when not having the throttle body?

[PSIG]

The stories of turbo lag are mostly greedy kids throwing a big turbo too large onto their engines for peak HP. If you size the turbo properly to the application, you get boost when you want it, and can regulate the boost through the range very effectively. If you need low-rpm boost and less on-top, then size it that way. I'm not promoting turbo, but there are too many bad stories about all power adder types that are poor application.

One more time:

Boost profile SC vs Turbo.jpg (49.01 KiB) Viewed 651 times

I did not review your videos, as they are long and I don't know where the info or question is. Please post videos with specific info by copying the "Copy URL at the current time", so we can go right to the info in-question.

To the second throttle body (and I'm guessing your question here), there are different reasons for this, and a common one is to enlarge or add to the original for more flow. With a turbo, you typically push the air through the TB, and most SCs you pull it through. The turbo compresses the air so the volume is the same, just more dense; while the SC has to pull much more ambient-pressure air through the same restriction as NA. At a certain point it does become noisy as the airflow approaches supersonic.

The bypass? There are different ways to use one (single or dual-port, and electronic), but for basic bypass to increase throttle response and cruise efficiency, the bypass is increasingly open when inlet pressure is decreased (vacuum). it is not on/off. Dual-port allows boost recirculation. Operation is automatic for basic function. Each is adjusted or tuned with spring pressures and optional boost bleeds.

This should look familiar. And what's that PCB... a Speeduino V0.4.

[JHolland]

I just had the towing-fairy-tale-action-story nicely typed up, but when I posted it it asked me to sign in. So it's gone ...
The short answer is: why not!

A guy in our village was towing a large trailer with a big load, using a small car; coming down the hill the trailer pushed the car through someone's garden wall, the magistrate took his licence away. It was a listed building and it ended up costing over £20k to repair a fairly small wall.

[huramentzefix]

The stories of turbo lag are mostly greedy kids throwing a big turbo too large onto their engines for peak HP. If you size the turbo properly to the application, you get boost when you want it, and can regulate the boost through the range very effectively.

I have done some research and have been looking at many dyno-diagrams of the VAG 1.8T engine. Thanks for that.
I was surprised at how low rev's that thing puts out good torque.
"BUT" they all have adjustable cam timing these days.

Which is not a problem because I am looking for low-end torque only.

It is still not going to be a turbo because it is simply to costly and complicated and I have bought the compressor already.

The supercharger that I own is a Mercedes W203 Eaton A2710902080 good for 160HP.

The bypass? There are different ways to use one (single or dual-port, and electronic), but for basic bypass to increase throttle response and cruise efficiency, the bypass is increasingly open when inlet pressure is decreased (vacuum). it is not on/off. Dual-port allows boost recirculation. Operation is automatic for basic function. Each is adjusted or tuned with spring pressures and optional boost bleeds.

The supercharger that I own is a Mercedes W203 Eaton A2710902080 good for 160HP.

It is electronic dual-port boost recirculation and is one complete unit, everything included.

The idea is to independendly stand-alone control the recirculation throttle body via D-Stages controller with arduino and independend MAP sensors.