Bob Neese

I thought this was an information board, not i've got a secret.

[ January 01, 2002: Message edited by: Bob Neese ]</p>

Black LS1 T/A

[quote]Originally posted by Bob Neese:
<strong>I thought this was an information board, not i've got a secret.

[ January 01, 2002: Message edited by: Bob Neese ]</strong><hr></blockquote>

Lighten up, Bob. <img src="gr_stretch.gif" border="0">

We're just instigating thoughts and ideas.
When we attack a problem at work, we have a "brain-storming" session where ANY idea, no matter how far-out it is, is considered. Most will be discarded, but often some really good points come up in such free-for-alls.

I only waited a few hours to confirm the question I raised... but look at all the GREAT discussion... the ideas generated, the warnings offered.

This kind of discussion is GREAT! There are guys with good brains, vast knowledge and varying experiences on this board. I enjoy it. <img src="gr_stretch.gif" border="0">

Black LS1 T/A

[quote]Originally posted by Jay_@_GWP:
What happens when you induce a vacuum state?
What effects take place?

Answer those and you'll get an idea of what I'm playing with.

Jason <hr></blockquote>

Let me start by being simplistic...

1. Matter (air, fluids, even loose solids) are attracted to a vacuum.

2. Inducing a vacuum lowers pressure (ha ha).

If you could somehow utlize a vacuum source to deplete a boosted source, could this function as some sort of boost regulator?

OK... I know it's a stretch! <img src="gr_tounge.gif" border="0">

MIGHTYMOUSE

iTrader: (59)

go huge with pullies and run a wastegate between the sc and the maf..

yea it will take a lot to turn, but you wont notice it.. the crank will notice it.. so all is good till u snap the end off <img src="gr_stretch.gif" border="0">

Nickn20

I cant wait till we have LS1edit for timing control, we wouldnt have to worry as much about boost control, just timing control <img src="gr_grin.gif" border="0"> so when you want to up the power, just add octane and timing, hehe

how much boost can you run on 93 octane, with a stock PCM?

Black LS1 T/A

[quote]Originally posted by Nickn20:
<strong>I cant wait till we have LS1edit for timing control, we wouldnt have to worry as much about boost control, just timing control <img src="gr_grin.gif" border="0"> so when you want to up the power, just add octane and timing, hehe

how much boost can you run on 93 octane, with a stock PCM?</strong><hr></blockquote>

With our 10.1:1 compression ratios, I'd say 5 or 6 would be a definite, 7 or 8 PSI would be safe but pushing it and 9 would be risky.

If I NEVER wanted to worry about Race Fuels or Octane Booster scenarios, I'd go no higher than 7 PSI.

Any higher and I think you will at least SOMETIMES need to supplement the pump gas. If you can only get 92 in your area, I wouldn't run any more than 5 or 6 PSI, to be honest.

1dirtyZ

iTrader: (1)

a toulene buying we will go , a toulene buying we will go , hi ho home depot , toulene buying we will go!! <img src="graemlins/gr_devil.gif" border="0" alt="[devil]" />

XLR8NSS

iTrader: (4)

Torco ordering we will go, Torco ordering we will go, Hi Ho High Octane, Torco ordering we will go.

<img src="graemlins/fluffy.gif" border="0" alt="[Fluffy]" />

If you want to hear me sing the above I'll send you the audio file. <img src="graemlins/gr_guns.gif" border="0" alt="[guns]" /> <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" /> <---Me singing <img src="gr_grin.gif" border="0">

[ January 01, 2002: Message edited by: XLR8NSS ]</p>

Nickn20

I have a sweet little hookup down here, I get 104.5 unleaded for a very nice price.... <img src="gr_grin.gif" border="0">

Bob Neese

Black ls1 T/A,
I'm sorry, it was a little 50's game show shot at levity. Bob

Black LS1 T/A

[quote]Originally posted by Bob Neese:
<strong>Black ls1 T/A,
I'm sorry, it was a little 50's game show shot at levity. Bob</strong><hr></blockquote>

Not a prob! <img src="gr_stretch.gif" border="0">

Give us a little smiley or wink to let us know you're joking... it sounded like you were agitated at the thread/posts.

It's all good, though...

If Jason doesn't expound on his post, we might have to beat up on him. <img src="gr_images/icons/wink.gif" border="0">

RacerX

OK, so was I right about waste gate?

Black LS1 T/A

[quote]Originally posted by RacerX:
<strong>OK, so was I right about waste gate?</strong><hr></blockquote>

I already answered. <img src="gr_stretch.gif" border="0">
I also stated there is no additional hardware, so you are not reading the posts. <img src="gr_images/icons/mad.gif" border="0"> <img src="gr_stretch.gif" border="0">

Basically, what I said was this:
-----------
There is no enormous slacking of the belt.
Only a minimal change can make the difference between losing boost and having max boost. It will track on the pulley straight and true, and you are not doing it enough for the belt to sling off.

Forgetting to check tension periodically can result in degraded boost levels over time... in often barely discernable increments...
-----------

I have seen my boost drop, over the period of a few weeks, to 7 or 8 PSI from nearly 10. A little tightening of the belt corrected that. A slight loosening returned it to 7 or 8 PSI.

The belt is tighter than my other stock belt. If you ask me, you have to tighten the blower belt TOO much to ensure full boost. I think the front seal may leak sooner from the tension. Then again, maybe not. But to get full boost, it IS very tense.

Black LS1 T/A

I like Just_ _ Me's idea. I think Jason is right about venting boost... it's inefficient.

What if, instead of just blocking air flow arbitrarily in Just_ _ Me's scenario, you actually created a Venturi stricture, similar to what Jason@GWP was hinting at? Venturi's induce a vacuum and lower temperature on the other side. If I got it right, I think that is what he was saying. But they are keeping his butt so busy over there building monster FI machines, he hasn't had an opportunity to try out his theory.

Either a plastic molded piece or aluminum should do it, don't ya think?

How about that aluminum piece inline between the air filter and the compressor's inlet hat. What if you simply swapped out that piece with your Venturi? Here's one design I found:



Buy a small pulley and put on your street restrictor for pump gas. Then swap to your drag connector when you use race gas.

What if it were adjustable? Jason's got me going, here. <img src="gr_images/icons/cool.gif" border="0">

Here's another design I located:



What if this could be modified to actually vary boost from inside the car? What if it could actually be used to provide max boost down low for max torque and instantaneous boost, but as boost increased with RPMs it is adjusted down to decrease max peak boost?

With my 3.20 pulley I see an instant 8 PSI of boost since I have a stall converter. Guys without stall might see at lest 5 PSI VERY quickly. Then, instead of 10 or 12 PSI at top RPMs, as the venturi were adjusted inward, max boost may be limited to, say 7 or 8 PSI.

And don't forget the venturi's cooling effect because of induced vacuum... sort of an ante-cooler. <img src="gr_images/icons/wink.gif" border="0">

Jason... you got this working, yet? <img src="gr_grin.gif" border="0">

Also, the manipulation of the intake air would ot have to be dramatic to induce measurable changes at the outlet of the blower... the proportions of change are not 1:1, but more logarithmically related... do I have that right, Jason?

What a swell idea! Inversely swell. <img src="gr_grin.gif" border="0">

Black LS1 T/A

This is what I finished fabricating today (but it is rainy and snow-bound outside, so I'll have to wait to try it).

http://www.mlbuie.com/transam/Black_...ack_ls1_ta.jpg

If my diagram is not explanatory enough, ask questions.

The plastic insert not only restricts flow, but also forms a venturi, which arguably would create a slight vacuum, resulting in some temparature decrease.

If my little amateurish design will actually produce a measurable temparture drop, that is yet to be seen. But I feel it will produce the drop in Outlet pressure.

Black LS1 T/A

Jason, is this something similar to what you were describing to me?

Rock

Must be great to have a garage Mike! It's great to see everyone thinking here.

That second diagram looks just like a needle jet setup on a motorcycle carb. The non pointy ends of the needles have slots to shim the needles to enichen/lean out the mixture. They are usully utilized at 25%-75% of throttle opening to compensate for the natural lean condition in midrange. Nowadays they use TPS/RPM signals to enrichen the midrange in conuction with auxilliary pumps powered by the alternator.

Just a little tidbit of info. I'm curious to see results. I just bought an autotap and have to find a lap top.. I'm slowly catching up with the times! <img src="gr_images/icons/wink.gif" border="0">

Rock

BTW Jason, the skip shift eliminator in the custom programming was a nice surprise. <img src="gr_stretch.gif" border="0"> I'll be calling you this week with a few questions.

Rock

[quote]Originally posted by Black LS1 T/A:
<strong>

Let me start by being simplistic...

1. Matter (air, fluids, even loose solids) are attracted to a vacuum.

2. Inducing a vacuum lowers pressure (ha ha).

If you could somehow utlize a vacuum source to deplete a boosted source, could this function as some sort of boost regulator?

OK... I know it's a stretch! <img src="gr_tounge.gif" border="0"> </strong><hr></blockquote>

Venturis decrease pressure, but trade it for velocity, correct? In other words, the energy is just converted from one form to another. Mater and energy don't just disappear, they change states.

Placing a venturi may create certain harmonics in the blower inlet too. You may find that placing the venturi in different spots of the intake tract will make the blower more efficient in certain RPMS.

Just like tuning header length to pull exhaust from the combustion chamber, and draw in more air/fuel during overlap. Less work the pistons have to do.

Black LS1 T/A

Nothing conclusive, yet.
Still wet from the snow, etc.

But, I did find some dry spots to WOT it.

Let me say first that I won't have final conclusions until I get my ET Streets on and run for a quarter-mile somehwere safe. But here's a first impression. Also, keep in mind that I have a SY3500 that makes my boost come on quickly.

When I can get a dry patch to hit it (running about 45 or 50), I see an immediate 6.5 to 7 PSI, then about 8 thru most of my RPM range. BUT, it climbs just before the shift. I think about 9 PSI (it was hard to keep an eye on the boost guage 100% of the time). Without the restrictor, I usually see 8 to 9 PSI immediately, topping off at 9.5 to 10.

Check this, though... Rock, you may have something.
I think air velocity introduced by the venturi design may complicate things in another way, however. I also just hit it down low for very fast buildup of RPMs and mucho spinning. It still approached 10 PSI, and once when I spun on wet pavement knowing I'd have to back out right away, it hit 11 PSI before I released the throttle. RPMs was around 6500 RPMs, but that is about what it did without the venturi/restictor before.

Keep in mind a 2" opening may not be much different than 3" in this context... I may need to reduce the cross-section by about half (about 1.5") to see a truly measureable reduction. But, acutally, 7 to 9 PSI boost range of travel would be MY personal ideal, which is what I'm seeing right now when I control the spinning.

After my little run back home with the '71 Camaro, I've been called out this weekend to run a '99 Camaro SS that's spraying, a built-up Mustang (they say it's in the low 8's on motor) and some big-block Chevy that's supposed to be running low-7's in the 8th-mile on the motor.

I may run the Camaro and Mustang with the restrictor and run the Big Block uncapped. I may need all 10 PSI for that run. <img src="gr_grin.gif" border="0">