ECUTune Stage III twin screw supercharger sign up - Page 50

mikecg · #**736** 05-20-2006, 08:48 PM

Well, I found out today that the car runs fairly good even with the S/C not working. I fried the S/C belt today, which knocked the altenator belt off. I drove the car about 12 miles home with no problems, with the exception of the exspected. No altenatro = batt, brake and lamp tights on on the dash and no power steering. The only issue with the engine cause by the belt failure was a slightly rough idle.

longassname · #**737** 05-21-2006, 10:59 PM

I figured out how to route the belt like I have it on my 12 lb pulleys for the 9 lb set up. It's pretty slick actually. Gives us almost complete wrap on all the pulleys. I didn't have the camera at the shop with me today but I'll take pictures tomorrow.

Mike, the belt is going to be either a 5060380 or a 5060390. Either is likely to work as we have a great deal of adjustment available. I'm shooting for the 5060390 as it will maximize wrap unless it turns out being a little too long. I'll let you know tomorrow.

longassname · #**738** 05-22-2006, 11:49 AM

if anyone has a power steering pump they would like to sell cheaply that will help the cause. I need a new one to go on the bench engine.

longassname · #**739** 05-22-2006, 11:52 AM

Also if anyone wants the 6 lb set up that's on the table now too. The new belt wrapping should work with those pulleys too. Personally I'd run more and I won't be making more pulleys that size but I've already made 2 of those crank pulleys so If anyone wants them they are an option.

SVXRide · #**740** 05-22-2006, 01:01 PM

Quote:

Originally Posted by longassname

Also if anyone wants the 6 lb set up that's on the table now too. The new belt wrapping should work with those pulleys too. Personally I'd run more and I won't be making more pulleys that size but I've already made 2 of those crank pulleys so If anyone wants them they are an option.

Mike,
How does the 6# crank pulley differ from the size of the stock crank pulley?
-Bill

longassname · #**741** 05-22-2006, 01:09 PM

It's much smaller. The smaller the crank pulley the lower the boost. In order to get hood clearance we use the smallest possible supercharger pulley which is 2.3 inches and vary the diameter of the crank pulley to change the manifold pressure. I hadn't before now figured out how to get the belt down between the power steering pulley and supercharger pulley with the smaller crank pulleys; now that I have I can get much better wrap. Wrap is especially important with the small 2.3 inch supercharger pulley. Because it is small we need to maximize wrap to maximize contact area and maintain grip.

Quote:

Originally Posted by SVXRide

Mike,
How does the 6# crank pulley differ from the size of the stock crank pulley?
-Bill

longassname · #**742** 05-22-2006, 10:07 PM

Ok, here's a picture of the new supercharger belt routing. As you can see all the pulleys are completely wrapped so we won't have any belt slip problems anymore. I won't be at all suprised, in face I expect, to see the boost #'s associated with each size crank pulley go up.

Mike, if you want to pick up a belt and a bushing I'll send you a double bearing idler so you can switch over to this belt routing. The bushing is to fit the idler pulley you have on your power steering pump bracket now onto the factory tensioner that goes on that bracket. You can continue to use the idler the way you have it now too but it's a little more convenient to make use of the tensioner. You can get the bushing from napa and the belt from anywhere.

Napa # for bushing: tem09781
napa # for belt: k060390
advanced # for belt: 5060390

Suby Fan · #**743** 05-22-2006, 10:31 PM

where did the alternator go?

longassname · #**744** 05-22-2006, 10:35 PM

there just isn't one bolted on. I didn't change anything besides the supercharger belt. The alternator and the ac are the same as they have been.

Quote:

Originally Posted by Suby Fan

where did the alternator go?

mikecg · #**745** 05-23-2006, 05:04 AM

Quote:

Originally Posted by longassname

Ok, here's a picture of the new supercharger belt routing. As you can see all the pulleys are completely wrapped so we won't have any belt slip problems anymore. I won't be at all suprised, in face I expect, to see the boost #'s associated with each size crank pulley go up.

Mike, if you want to pick up a belt and a bushing I'll send you a double bearing idler so you can switch over to this belt routing. The bushing is to fit the idler pulley you have on your power steering pump bracket now onto the factory tensioner that goes on that bracket. You can continue to use the idler the way you have it now too but it's a little more convenient to make use of the tensioner. You can get the bushing from napa and the belt from anywhere.

Napa # for bushing: tem09781
napa # for belt: k060390
advanced # for belt: 5060390

I'll see if I can get them tonight.

SVXRide · #**746** 05-23-2006, 02:15 PM

Nice!

any slippage now and you've got bigger problems going on

-Bill

longassname · #**747** 05-23-2006, 05:46 PM

There just wasn't enough wrap around the supercharger pulley the way it was routed with the smaller pulleys. Like you are saying, this will definitely fix it. There is no way there will be belt slip with this arrangement; you can't get better than this.

Quote:

Originally Posted by SVXRide

Nice!

any slippage now and you've got bigger problems going on

-Bill

longassname · #**748** 05-23-2006, 05:59 PM

Nemesis Destiny · #**749** 05-24-2006, 03:23 PM

I've been meaning to ask, regarding the bypass valve: when does the valve open and close? Is it triggered by load somehow, or simply by RPM? Part of its purpose is to allow economical highway cruising, and so knowing how it functions is potentially vital to choosing gearing when swapping transmissions.

longassname · #**750** 05-24-2006, 07:16 PM

The function of the bypass valve isn't unique to our system; it's the same for any supercharger system. The bypass valve is vacuum actuated. When there is vacuum in the manifold the bypass valve is actuated--it is opened. The throttle is what controls whether there is vacuum in the manifold or not. If the throttle is closed there is vacuum in the manifold and the bypass valve is opened. If the throttle is open there is not vacuum in the manifold and the bypass valve is not opened. Partial throttle positions vary between the two.

Perhaps considering what the function of the throttle is on a naturally aspirated car will make it's function on a supercharged car more obvious. A throttle restricts airflow into the engine. It creates a restriction which regulates manifold pressure on a scale from full vacuum to close to no vacuum. With a supercharger and bypass valve installed the scale that the throttle is controling is just expanded to include positive manifold pressures.

Quote:

Originally Posted by Nemesis Destiny

I've been meaning to ask, regarding the bypass valve: when does the valve open and close? Is it triggered by load somehow, or simply by RPM? Part of its purpose is to allow economical highway cruising, and so knowing how it functions is potentially vital to choosing gearing when swapping transmissions.