Supercharger pulley

I'll see what I can do, I know I won't be able to do it alone. Between it being a 1stgen and a stick, my hands are full just trying to keep myself in the cab. :lolly:

I'll stop by a buddies this week and see if he'll help me out.



Also, that TB came with a couple return springs that I forgot about. They sit against those square stands and the throttle linkage. I'm going to see if I can use them instead of trying to find a mounting point for a normal return spring. Should help keep things tidy.
 
Gonna give this little ghetto fellow a try. It doesn't change the cracking pressure a whole lot, unfortunately, but it doesn't hurt.

Another thing I found out is the lower chamber of that actuator starts leaking air around 20psi. I didn't take it much higher with the tester, but I can imagine it doesn't look good at 45psi. LOL

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Oh, and **** those stupid springs the TB came with, I've pretty much ruined my fingertips trying to get them to work.
 
Little test drive to Wendy's for dinner before I head home, turns out that spring actually helped a good bit. It's bumped my idle psi back up to 2, it was down to 1-ish since that TB didn't close all the way with just the actuator spring returning it.

It has delayed the opening by a good bit actually, I was able to get the blower up to 8psi in normal driving. Before, it would immediately dump all interstate pressure around 4psi when under load. Now it holds to 8, and still manages to maintain a couple psi until you really give the turbo a reason to spool.

I've still got a bit of a dead spot between the valve wanting to open and the turbo getting spooled. I'm thinking of getting a smaller pulley for the blower and seeing what happens. My spring selection isn't that great, but I think a pulley may be easier to find than a stiffer spring that's still able to stretch far enough. :lolly:


Also, some of these results may be skewed somewhat. I brought my timing back a few degrees while I was in the shop. Somebody was a little grouchy starting this morning, and there's no way I'm dragging a cord outside until it's at least in the teens.
 
Nobody ever told me being beautiful would be this hard...

I've got a belt squeak now anytime I'm above 5psi interstage. It is especially unhappy between shifts. I'm not sure what it spikes to then, as my temporary gauge isn't backlit, but it's nice to know the TB is closing and keeping some amount of boost built up.

I have a feeling it was all that black paint I smothered my drive pulley with. This is why I don't paint ****. LOL
 
Tacoclaw said:
Nobody ever told me being beautiful would be this hard...
Click to expand...
I've found being beautiful to be quite easy, it's just that the hard part is getting other people to share the same belief. :hehe:

I'm still watching and learning, Levi. :cool:

Mark.
 
Well, any specific questions anyone has, feel free to ask, I'll answer them to the best of my abilities. Although, as you can tell by him informing me of the two separate filter information, Carl still has much more know-how about this stuff.

Thanks again for all your help, everyone, especially Carl and Mark. :thankyou2:
 
I have a hard time conceptualizing how to make a TB valve like that work well in this scenario. I think you may be best by tuning it to stay shut until the turbo starts to draw a vacuum on the SC. Thats prolly the best way to minimize the flat spot. Just remember, too much vacuum can cause oil seal leaks in the turbo compressor.
 
Well, the way it's set up now, interstage psi is holding the TB closed via the top of the actuator, and manifold pressure is trying to open it. With no input from the turbo, it will stay closed with whatever spring pressure is applied to it.

Once the turbo stares to compound the boost a little bit, it is then just up to whatever spring pressure I've got holding it closed to decide what pressure the TB starts to crack at.

However, if I really lay into the turbo, it should technically cause an interstage pressure drop, which would unload the upper side of the diaphragm and make it that much easier for the TB to be opened. I'm still undecided on whether or not this is helpful, as just having regulated manifold boost may actually work better.

The factory spring in that stock actuator is pathetically weak, it won't even register on a gauge before it starts moving with atmospheric pressure on the upper side of the diaphragm. I feel that if I have to go to a stiffer spring again, that having the upper port on interstage air will ensure that the TB is able to be fully opened, since it's apparently bleeding off any air it gets over 20psi.


I may also end up regulating the manifold air into the lower chamber to try to keep the damn thing from leaking off. If that's the case, I'll definitely have to have a way to unload that upper chamber, as 20psi probably won't be enough air to get the TB fully opened or reacting fast enough in general.
 
Alrighty, folks, here's some vids for you. Not much I can think to explain on the first other than the gauge reads interstage pressure, if there's anything specific you want to know about it just ask.

[ame="http://www.youtube.com/watch?v=FuRymXJL7bQ"]http://www.youtube.com/watch?v=FuRymXJL7bQ[/ame]

On this one, I did the best I could. It's a pull through about mid fourth, I just cruised through 1st and 2nd to keep my axle from wrapping like a pretzel, then I rolled into it in 3rd. You can see there's some lag, but I've got the AFC unhooked so I'm short on spooling fuel. Total boost on this run never broke 18psi.

[ame="http://www.youtube.com/watch?v=bdqkdOfyo2g"]http://www.youtube.com/watch?v=bdqkdOfyo2g[/ame]


I also got my belt to stop squeaking. Turns out I had them swapped and was running my XX,XXX mile accessory drive belt on my blower. Got about 5 miles down the road before the good belt started squeaking though. I'm gonna pull my drive pulley off and hit the grooves with the sand blaster. I can see by the paint that the belt isn't sitting as far down in them as it should. I blame the paint.
 
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We had an old non-turbo idi that was pretty fun to drive around. With it's compression the off-idle pickup was awesome, it drove just like a gasser. Then that was it, it literally never pulled any harder.

Is the blower going to be your only means of boost? As big as those engines are, it'll take a good sized blower to even try to keep up with it. I was surprised how quickly my engine outpaced this M112. Even with the boost number going up, you could just feel the power falling off.

I'd look into a way of keeping it very well intercooled if you're wanting any real performance gained out if it.
 
No real updates, I put some 56" Chevy leaves on the rear of the truck so the raping can commence, but now the belt is squealing almost nonstop.

I blasted the drive pulley and it didn't change a thing, so I'm wondering if Carl's prediction of crank pulley slippage may be coming into play. My water pump is leaking and my timing cover started after the timing bump, so I'm going to try to plug all these leaks before I tear back into the accessory drive.

I'm pretty pumped that my new front main stopped the crank leak, I'm sure it's going to be completely worthless when I pull it back off to silicone the cover. :doh:
 
Put my water pump on and dug into the belt squeak. After a couple minutes of head-scratching, I finally tracked down the bastard. It turns out that the idler that runs right before my drive pulley wasn't tracking correctly. It was the one that making my belt jump over a rib, so I sanded it's mounting surface crooked and turned it to make it track right.

I sat and watched the belt, and you could see it walk out on the pulley, then jump back in with a chirp. It seemed to coincide with the place where the stamped the part number on the belt.

After turning the mount all over the place trying to get it to line up naturally, I finally got mad and scuffed the pulley with a piece of sand paper. It immediately stopped the squeak, and the belt started following it perfectly. :)

Now I've got to sit down with a welder and fix all my boost leaks. I keep wanting to play with springs and air pressure on the actuator, but it's pointless if everything else isn't working perfectly. I learned that lesson with the twins, I was just hoping I could ignore it with this setup. :lolly:
 
Is there anything more depressing than putting a leak tester on your intake? I can't think of anything...

867A0D44-595F-4F90-B117-464C7D7C07AC_zpswhzz6bj4.jpg


DC22C658-4E8B-43E5-AA5D-19361D3209AC_zpscto9ld4j.jpg


Not like they matter, they're drops in the bucket compared to that damn throttle body. It's dumping past the butterfly and through the shaft seals. Bleh, I have no idea how to get that butterfly to seal, but that's a huge leak. I couldn't get shop air to go above 4psi through a 3/8" hose...

The butterfly wouldn't completely seal from the get go, since it was made to have a gap for idle (and because it's Chinese junk), so I buzzed on the edges with one of those gasket cleaner discs. Got it to open and close easily, but there's just no way I can think of to get it perfectly round again to seal.

Bleh... Guess this gives me a chance to pull the SC mount and retap the lower, rear mount hole I boogered up. :bang
 
Meh, I got pissed and depressed, didn't work on a damn thing. I made a heavier spring for my bypass to see what would happen and hit the road. It drove even better than before, maintained 5psi interstage and 10psi at the manifold cruising at 55 in 4th.

Then I decided to try a little power run and see how the spring did up top.

Not well. :hehe:

This is what happens when you don't bypass enough, if you can't see the gauges the interstage spikes(drops?) to 12 and the manifold boost can't go over 20psi.

Hard roll into 1st, grabbed second a little too hard for someone who's trying to steer and film with one hand, then rolled into third hard. About 1/2 way through third I noticed it was being really doggy and looked down at the gauge. Noticing it was buried in the vacuum side, I let off of it, then I decided to see what my other gauge was doing so I hit 4th and rolled into it.

Guess I'm going back to the old spring.

[ame="http://www.youtube.com/watch?v=3aBlqZBH-IU"]http://www.youtube.com/watch?v=3aBlqZBH-IU[/ame]

Also, **** my pyro. :ft:
 
I figured out what's going on with my TB, turns out the diaphragm inside of the eaton actuator exploded. Guess it's not happy with 40+ psi...

I've got to figure out something else now, probably just a Chinese wastegate actuator off EBay with two ports and a low actuation pressure.
 
I'm not sure how you could control that without some smart logic in a controller. It's painful to watch that charger pull a vacuum on the supercharger, that's for sure.
 
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Well, when it's working right it doesn't pull a vacuum.

The explanation is up there in post #209, it actually seems to work really well.

When it's working correctly it will typically hold a couple psi of interstage until I really put a load on the turbo, then you can watch the needle drop right to 0psi and stay. Very minimal vacuum when it actually opens like it's supposed to.
 
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