General Supercharger Thread

Looking at old acceleration videos I have punching it from a cruise, even on the 80mm pulley it comes in pretty fast if you quickly crack open the throttle.
1500rpm - 4psi
2k - 6psi
2800 - 7psi
4000 - 8psi
4500 - 9psi

I’m sure it hits both harder and faster now on the 77.5.

 

For a boost-cut solution, just tee in one of these on your boost reference port behind a ball valve, limits you to 10psi and easy to switch back and forth, problem solved

https://compressor-source.com/produ...ressor-pressure-relief-safety-pop-off-valve-1

 

Wow...I need to get some logs so I can see what mine's doing on the 85mm

 

Sounds like the OG bic pen spring boost controllers we used in the mid 90's on turbo cars.

 

Yeah...it's pretty janky, but the more I think about it...the more I think it would work. You could get a real BOV and come up with a solution where it was sealed until it pressurizes...it shouldn't cause a vacuum leak, and you'd get the zu-too-too and pssh pssh noises as a bonus!

https://www.youtube.com/watch?v=4PwqaYY42I8

 

I do like your thinking here honestly. I just wonder if a small 1/4” pressure relief will adequately bleed off the excess pressure/volume to keep it from going over 10psi, it might since most of the volume will still be going into the cylinders? It’s just a lot smaller than the bypass valve diameter. I’m also curious about the ability of those relief valves to open and close and seal well after hundreds to thousands of cycles. Keep some extras in the glove box I guess lol.

 

Normal driving will hit 5lbs. Big pedal gives me 9.5lbs around 3k rpms

 

https://www.tundras.com/threads/yot...pment-and-feedback.112705/page-2#post-3382203

 

Is that a one-and-done flashed tune or do you guys get logs and tweak it for the individual vehicle?

 

Looks like a good mod for the Harrop

 

We don’t need no stinkin throttle body!

 

That’s nice looking torque curve.. me likes it

 

I definitely see boost very very quickly. Cruising and light blip of slight acceleration 6psi

 

For the BMW, the AA uses a Rotrex SC that has a 7-rib upgrade pulley, the car uses 6 rib. Can I get the 7 rib?

https://store.activeautowerke.com/p...t-level-1-rotrex-c38-blower?variant=768863499

 

These are intended as a one-and-done as you say, so that someone can take it and run it confidently like they would the Magnuson calibration for example.

appreciate you sir

 

Are you getting your threads mixed up?

 

Nope, belts and pulley ribs are universal.

seems to me if it’s one rib bigger should be ok but what do I know?

lol

 

Well it is a "General Supercharger Thread"...so I guess we can let it slide

The 6-rib belt "should" work on the 7-rib pulley if the ribs line up...but you'll probably go through belts faster if there are any alignment issues. Might want to run it by a Bimmer forum.

 

Thanks, I did. In a thread specifically about this set up, the previous last post was in 2011 & it's been a few days, nada.

lol

https://www.bimmerforums.com/forum/...Rotrex-S-C-on-s52-Z3M&p=30916339#post30916339

Also, as far as the fitment, it is just a need to mess with the hoses to fit the hood slope, I found several YouTube videos where the issue is resolved.

I need to find a meth kit now too.

 

One rib bigger is fine. On my supercharged LS the supercharger pulley is actually two ribs bigger and the belt spacing ends up using the 6 middle ribs out of the 8 total. As long as the spacing is fine I wouldn't worry.

 

Just stopped by the holy land.

 

Went and ran a few logs:
Harrop
85mm pulley
DW650's
stock airbox for now (Maggy lid waiting)
Stock TB
650' elevation (Hutto, TX)
55 deg and misting (DA ~700')
Stock exhaust and manifolds (axle cut)

AFR's 9.4-9.8 (will lean/smooth out a tiny bit)
MAF 4.98V @ 6,000RPM
Inj DC @70% @5,600 75% @6,000 (has me worried about the 80 and 77.5mm pulleys in the garage)
Knock feedback good
KCL is 18's (19 at low load/RPM)

Going to smooth the AFR's a little bit then will work on a Dragy run when it stops raining. (who'd crossed into Nuevo Laredo, MX recently?)

I'm also building a test rig to log after TB inlet vacuum and outlet boost via the Prolink. We went down the rabbit hole of compressor inlet restrictions a while back and I'd like to log what happens with the following: SABM, Maggy Airbox top, then get into larger TB's (I snagged one of @snivilous Harrop to LS adapters a few months back)

 

Guessing you'd hit the max MAF voltage before the max injector DC.

 

Not too worried there, the Maggy box should get me back onto the tables.

 

Is this good?
https://www.ebay.com/itm/251542763683?epid=2133135653

 

Yes, that's good!

 

The new style controller is a lot better and more reliable than their older style.

 

Thanks, looks like the V3 nozzle is also an improvement based on this thread:

https://brentfordracing.com/2021/01...ection-kit-installation-chemical-intercooler/

 

The 50/50 mix can help you with timing and run it a little leaner for more power with the larger nozzle pintles.
I haven't noticed it affecting my afr's at the 70/30 mix and I have no way of measuring IAT to see if additional cooling is happening. Just trusting the literature and experiences of others.