General Supercharger Thread

I have a friend who bought some weird old Mercedes, bunch of quirks. He takes it for a test drive, and gets back to the dudes house and pulls the key out and it doesn't turn off. He's like how do I turn it off, and the dude goes oh here. He pops the hood and grabs a hose and starts sucking on it and the engine dies. Apparently this was standard operating procedure for this dude to turn the car off

 

You gotta ask yourself how many other things he sucked on before he discovered the right hose.

 

I can assure you I have no idea
@Saltyhero13 might know

 

I strongly suspect that @snivilous was on the right track.

 

I have the maggy 2650

 

I assumed the 2nd nipple was for atmospheric reference or something of that sort.

 

Milking.
You can milk anything with nipples.

 

https://www.northamericanmotoring.c...ass-valve-theory-of-operation.html#post336228

Good explanation and discussion of bypass operation and the restrictor. On demos of a bypass valve it slows down how quickly the diaphragm moves from one state to another.

 

I think both @snivilous and @Silver17 are correct.

I think it is there if you needed additional control of the valve. Vacuum actuated bypass seems to be a problem for big cams, more overlap so they create lower vacuum. If you wanted to control the bypass referencing throttle body position or delay opening/closing above/below certain speeds/accelerator positions.

There are electronic type controller that go inline with the vacuum reference valves which I suspect they are acting like a variable restrictor (the brass nipple we've been talking about the last few posts) but there are others that control the valve using the atmospheric side. Can't remember the name of the product but someone posted the listing some months back.

 

Reduced temps again today but not as low. Sat between delta 18 to 24. I do notice the IAT readings blip to lower temps more before stabilizing when I give it gas; they are a little more jumpy. Possible my temp sensor or harness is pooping the bed with the reading jumping around on acceleration.

Another thought is my transmission temps are lower so my tranny HX is not dumping heat into my intercooler HX. "Feels like" I can get up to speed and coast around more effortlessly, noticeably my city MPGs have improved in shorter time.

 

Speaking of heat exchangers, is anybody running an all aluminum radiator? Does anyone feel it is warranted considering the extra HP/heat dissipation requirements of the SC? This is my first summer of forced induction and it's been relatively cool so far. But I know I'll be making some decent trips with a trailer in tow this summer. I've not had any issues with keeping the truck cool in the past, even pulling heavy in 100+ temps for four hours straight including a decent 3k+ climb up a mountain pass, I've barely seen the dummy gauge move on the dash.

 

Bypass valve actuator from a Whipple.

 

@reywcms said before that he has seen a lot of failed aluminum radiators on other trucks and said OEM holds up the best. As for the heat, I’m on my 3rd summer towing with the blower and have never had a problem with too high of coolant temps despite pulling pretty decent hills in 90+ heat with the AC on. For the most part I never see over 210, and I’m probably due for a new thermostat and hoses at a minimum. I only ever saw 220+ once and I was stuck on a back mountain road behind a loaded dump truck going up very steep switchbacks for well over a mile at 25mph pulling my 7500lb TT. That scenario was like a torture test for the whole drivetrain and cooling system.

 

Was there a brass orifice?

 

Good to know. If it ain't broke... There is one pass in particular that I was worried about running in to the exact same situation that you were in - getting stuck behind a large truck going 20 mph up a 10% grade. But then the part of the road sloughed off the mountain... I'm prolly due for some hoses as well; when they installed the SC, I had a couple of smaller coolant hoses that were leaking a drop here or there.

 

If I recall correctly I remember him mentioning the mounts were breaking. If that is the case I wonder if there is a way to reinforce them. He and his crew probably torture test them with all the jarring.

 

Not that I saw. That's how it came out off the blower; the new replacement didn't have a brass orifice either.

 

If you go aluminum radiator, might as well pair it with a vented hood because that heat still needs to dissipate somewhere

 

I'd heard about that, Teton Pass outside of Wilson?

 

Saving for later:
https://youtu.be/ZGoyhgmkmXk?si=UOTFTmDgfHSEU1Wx

 

So, about hood vents... I'm conflicted about the thought process as I'm trying to recall from whence I gathered this little tidbit of information, but essentially, the theory goes that having a clear path (meaning, only one real direction it can go) for the hot air to travel under the hood creates the best cooling at speed. Air comes in the front of the vehicle, is directed through the radiators, past the engine block, down the back of the firewall, and out underneath the car where the air passing under the vehicle helps evacuate it from under the hood. In contrast, hood vents are supposed to cause a second path for the air to travel, but since not ALL the air can travel that direction, it creates eddy currents under the hood around the motor, causing flow issues through the radiator as you now have more positive pressure under the hood.

At slow speeds (under 15 or 20 mph) there isn't enough air flow through the radiators and under the vehicle to have an effect on the air flow, so hood vents are effective at low speeds only where you need to evacuate the most amount of heat possible given limited air flow.

I'm really trying to remember where I got that info from, but that's been my understanding of hood vents and their actual efficacy. I'm not saying your wrong, just that I don't understand the mechanics of it well enough to know.

Ha. Yup. Last time I drove up it several months ago, the road felt like it shifted going around a certain corner - like the whole truck moved two feet to the side. I figured they had just paved over a section and didn't make the the transition very smooth. When I heard about the failure, I knew exactly where it happened and laughed out loud when they showed the giant cracks in the road.

 

I have one and my temp gauge stays lower than with the stock unit.

 

I just installed a Mishimoto aluminum radiator. Before I ran at 196-206, now I am running at 177-181. It has been 111 to 115.

I also have a large aluminum SC coolant heat exchanger.

 

I did the CSF radiator and drove from Oklahoma to Abilene in 110 heat on a brand new super charger and it was cooling like a beast. I also upgraded the hoses (HPS) they are 3ply withstand heat up to 350F. Hoses definitely worth it, I honestly think if your going to do the super charger just replace the stock radiator.

fyi I was pulling a 7,000 pound boat going 75-80mph.

 

I'm guessing you don't have a real gauge to monitor actual temps?

Ive seen 235* on my sgII, yet the dummy gauge never moved.

I'm hoping those temps are more reasonable with a SCer.

 

I was definitely 235+ logging through hptuners. That supercharger needs every bit of cooling you can give it. I noticed my trans temps were little high as well. Also, for some reason I really think headers help a fuck ton and just hear me out. My truck literally sits at 2300rpm maybe -2 + 2 psi and is smooth as a rock at 70-75mph. Idk if the additional air flow coming out makes a big deal but it sure seems like it with a super charger + header combo. Feel like I am driving a semi truck haha… really need @snivilous tune my truck

 

I have access to the gauge via my head unit and iDatalink maestro, but I’m limited to four gauges plus the speed or tach. I was alluding to the contrast between the dummy water temp gauge and the dummy transmission temp gauge - I’ve seen the dummy transmission temp gauge move before, which is why I started monitoring actual temps via the head unit. I don’t typically monitor water temps anymore since they didn’t change more than 10 degrees. Now with the SC I plan on watching water temps again but it’s constructive to hear what others see for temps. Upgrades sometimes needs upgrades

But, ya, I realize the dash is dummy gauge..

 

Hot damn, 235?

 

@e30cabrio - was it a simple r&r or did it require fabrication? Asking simply out of curiosity since it's a possibility for me in the future if I don't like the temps throughout the rest of my towing season.

 

2650 here no restrictor to be found. Also on the PSB1 sometimes A/F won't show and it's just dash marks. Press hold left button, think it takes you to boost. Then press both buttons back to A/F-Boost. Clears the dashed a/f everytime.