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Discussion Starter · #241 · (Edited)
Why the post #114, because that is where I am now, with Black Beauties Performance, and these are the numbers I hope to beat.

View attachment 307853

For the record my 0 ~ 60 runs have been run with a full tank of gas, junk in the trunk, and the spare tire back there as well.

View attachment 307855
My goal was to beat what it originally was capable of doing while naturally aspirated, that best 4.3 second 0 ~ 60 time above, no matter what I did I could not beat it, it was almost a fluke getting it back then. Well not anymore what was run below was run in normal drive mode, just playing around with it, you can plainly see Sport Mode is not engaged.

Speedometer Car Odometer Vehicle Tachometer


Speedometer Car Vehicle Odometer Tachometer


Ry

Edit: The list is getting shorter to the cars that Black Beauty would have to take a back seat to. :)
 

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I usually do 0 ~ 60s by myself but tonight my wife was with me and we used the entrance ramp to the interstate, no practicing, coast was clear no traffic, it did spin off the line, and still ran a 4.6 time, full tank of gas, and junk in the trunk. (y)


(I KNOW you aren't calling the wife 'junk in the trunk'....)
 
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Discussion Starter · #244 ·
Now that I have had some time driving with the supercharger installed, the experience is quite exhilarating, but it is also hard to explain in words. I've spent a lot of time just experimenting on starting off easy and not neck snapping my passenger. All of that throttle experimentation is using less than 1/4, more like 1/8th throttle.

I previously had used 1/4 throttle naturally aspirated for a moderate take off from a dead stop. With the supercharger 1/4 throttle is an aggressive take off from a dead stop. Using a quarter throttle on purpose, supercharged, is like a half throttle or more naturally aspirated.

If that makes any sense at all.

AnyHoo, Still learning to drive it! Ry
 

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Makes sense to me...
 
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Discussion Starter · #246 ·
I had quite a few concerns in installing a supercharger on a 5.7 with over 78,000 miles on the engine, a friend was over yesterday and wanted to hear it run, so I popped the hood and cranked it up. It was purring like a mature cat, no weird sounds, actually better than it has ever sounded, almost like if the car could think the supercharger was what it had always needed.

Revved it so he could hear the supercharger whine, and asked if he wanted to take a ride, but he was pressed for time and asked for a ride later. He has always asked me to drive it himself, but I am not going to let him drive it, simply from watching him drive his own Mustang.

But listening to the engine running has pretty much dispelled my mileage concerns as it is really running good, and by the way, is still running the start up tune. I am considering changing the supercharger pulley from the 3.400 6psi to a 3.300 7psi pulley, from research they say if I am going to do that, do it before data logging and getting it fine tuned.

Unfortunately from 2 email requests to Magnuson to confirm which pulley to buy, I have gotten no solid response back from them. My dilemma is the pulley offset on the supercharger is .440.

Wheel Automotive tire Motor vehicle Rim Data storage device


Most of the 3.300 diameter pulleys I have found have a .400 offset, if any of you know the right pulley I would love to see a link to it! :) Ry
 

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Discussion Starter · #247 ·
Apparently Magnuson only has 2 pulleys with the .440 offset, the 3.400 I have, and the 3.200 I just ordered, which is an 8psi boost pulley, from all my research 8psi is the maximum safe boost for the stock 5.7, so we'll see. Ry
 

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Ry, I would say that if you are just ripping around town and not doing drag racing or such just keep it the way it is.

I drove that Hellcat that was supposed to be at 800rwhp or so and around town it wasn't any more fun than my car.

At the track I would love to have it blasting at full sing, seeing if I could best my PB of 131mph up the front straight at Road America. But everywhere else my car is essentially the same to me.

But your car is working great and I guarantee you have 100rwhp+ or more. Don't get greedy! lol
 
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If you go with the smaller pulley/ more boost you will probably have to look into a higher capacity fuel pump. 6 psi is about the limit for the stock fuel pump. You do not want to go lean at 8 psi- think melted pistons and busted ring lands.
 

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Discussion Starter · #250 ·
If you go with the smaller pulley/ more boost you will probably have to look into a higher capacity fuel pump. 6 psi is about the limit for the stock fuel pump. You do not want to go lean at 8 psi- think melted pistons and busted ring lands.
Pat didn't you tell me you had a difference in boost pressure from the supercharger on the 5.7 vs the supercharger on the 392? Seems like I remember that, if so, what was the boost difference? Ry
 

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Max boost was about 4.5 psi on the 392. Larger displacement and better flowing heads and exhaust. You’ll probably see a little less than 6 psi on your engine due to the long tubes.
 

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Discussion Starter · #252 ·
Max boost was about 4.5 psi on the 392. Larger displacement and better flowing heads and exhaust. You’ll probably see a little less than 6 psi on your engine due to the long tubes.
Thanks Pat, After a lot of research and knowing that Magnuson pretty much guaranteed the 6psi boost with their supercharger installation on a 100% stock 5.7L engine. Meaning, still running the stock exhaust manifold, the stock catalytic converters, and the stock OEM exhaust, that the Magnuson from all their previous 5.7L testing should be delivering 6psi of boost.

My 5.7 has Shorty Headers, High Flow Catalytic Converters, and High Flow Cat Back Exhaust, so my 5.7 is not getting the 6psi of claimed boost from the Magnuson. Even if I run an 8psi capable pulley it was still designed for a 100% stock 5.7, so I will not actually get 8psi from it, it will probably be closer to 7psi. Whether that requires a boosted fuel flow I guess I'll find out when the 3.200" pulley is installed for a test ride.

What do you think? Ry
 

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Pat didn't you tell me you had a difference in boost pressure from the supercharger on the 5.7 vs the supercharger on the 392? Seems like I remember that, if so, what was the boost difference? Ry
Boost is just a measure of backpressure in the intake stroke. The same supercharger/turbo setup on a higher displacement engine is going to lower boost pressure because of the increased displacement. You are sending in the same extra volume of air into a larger volume of cylinder. It is likely that you will increase power output from the engine at a lower boost level because of this.

Adding longtube headers as a variable to an engine that makes 500 whp at 6psi might drop the the boost down to say 4.5-5psi but you will likely be making the same power or more as the hot exhaust is expelled easier allowing for more of the boosted volume of air to enter the cylinder. So Boost PSI is not a direct measure or increased hp.

Moving to the 8psi range on your setup Ry might be "safe" but obviously you will have to tailor that setup to your actual engine. Doc's reminder about fuel is an important one, for example my kit from Arrignton would have come with a new pump and larger injectors if I selected the 8psi setup. Just be careful and thorough bumping your boost which I have no doubt you will be.

Keep us posted like always!
 
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Knowing how close you are to 100% duty cycle on your injectors would I think be extremely important before install that pulley. The SC is spinning at advertised rate even if you are not getting advertised boost. Spinning the SC faster is going to add more air which will require more fuel.

Do not be tempted by the machismo of a higher boost number, it is not the right metric to gauge the power you are making.
 
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Nice! So that begs the question then, can his ECU make enough change within the 3-5% that is allowed?
 
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Nice! So that begs the question then, can his ECU make enough change within the 3-5% that is allowed?
The ECU doesn’t make adjustments under WOT conditions, it’s not looking at the O2 sensors. Adjustments would need to be made for proper fueling at WOT and a wideband O2 sensor is the only way to do it right.
 

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Discussion Starter · #260 ·
That is way more power than I want to be messing with, my hats off to all of you seeking after that kind of power, but I learned a long time ago after I blew my dirt bikes motor from my fanatical driving, that if I rebuilt it, I was going to kill myself on it. I may be 69 years old now and December 13th will be 70, but I don't think I'll ever grow up, because I still act like a kid at heart sometimes, and then sometimes my body reminds me how old I actually am. I estimate my Challenger is somewhere around 450hp now and sometimes if you give too much accelerator, well you'll know it! With what I have now HP wise I cannot even imagine an additional 300hp, you Hellcat owners be safe out there brothers and sisters! Ry
 
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