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Whats To Much? 24cyl. 12 superchargers, (( updated 11-13))


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I'm particularly interested in the frame of the vehicle in the OP...rather a large cutout for exhaust header clearance where the frame would do well to be its strongest to support that massive amount of hardware. Just sayin'...

The Camaro in post #26 should be quite a nightmare to tune too, if my understanding of the plumbing is correct. The turbos appear to be blowing through carbs perched on top of the Roots-type blower (under an apparently dummy injector hat) but it would seem that all the boost from the turbos would blow out the front when the throttle butterflies open. Those fancy S-curves coming out of the turbos are big flow-killers too.

Someone please correct my understanding if I'm wrong here.

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I was thinking the same thing about the camaro. I would assume that when the butterflies open that he would loose boost. I found a video of the car on youtube and it seems to run really well.

I HAVE seen showcars over the years that had dummy blowers...once saw one with a GMC 6-71 and injection that had an empty blower housing (just stub shafts for the pulleys) and a Holley 4-bbl carb inside the blower. It ran fine too.

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26mpg? Surely thats not right

This is my best mate Stu's Scooby that he races in the HKS and Jap car drag series. 900 bhp on gas and his best time is 10.26. mpg is around 5 mpg

IMG_9791ptm10dj.jpg

Multi Supercharged truck engine is truly awesome :) wonder wether it's simply a feat of engineering, or going to be used in pulling? I reckon if it was, it could pull an entire city!

No, Your right, not 26MPG. It was 28MPG.. Sorry :) 100% sure. it is a Turbo 4.8 LS engine with an auto w/ overdrive. Ran 8.85@152. Stock bottom end 4.8 (Stock crankshaft, pistons, rods and bolts) Here is his youtube channel. He also has a civic or two that run 10 sec 1/4... Drives his Grandmother to church in the 4.8 powered car ;) There is an article about his car in LS1Mag? Last name is Lavoy...

http://www.youtube.com/watch?v=aGyL615C2Lg

Also look in "Hot Rod Magazine" They tested a stock bottom end 4.8 achieving 1200HP..

4.8

118 octane race gas

Twin 76mm eBay turbos

Cam

Ported heads

Arp head studs

Fast Intake and throttle body

26.8 psi for 1,203 hp!!! Still didnt go boom...

Made 60 Dyno Pulls and it never popped...

Edited by RadialDragon
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Hubcaps serve a very important purpose!

All these cars are legit. lol

I was a bit harsh! Moon disks on Bonneville cars make sense, and the simple caps that keep your hubs and wheel nuts free from dirt. Not so the fake alloy type that don't line up with the holes in the wheel behind so they don't fool anyone and reduce the cool air to the brakes, and unless they're held on with cable ties they fall off at the first tight bend:

post-12614-0-54584600-1384429213.jpg

They're too much to my mind, but I'll shut up now as I don't think a rant about hubcaps is what this thread is about!

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No, Your right, not 26MPG. It was 28MPG.. Sorry :) 100% sure. it is a Turbo 4.8 LS engine with an auto w/ overdrive. Ran 8.85@152. Stock bottom end 4.8 (Stock crankshaft, pistons, rods and bolts) Here is his youtube channel. He also has a civic or two that run 10 sec 1/4... Drives his Grandmother to church in the 4.8 powered car ;) There is an article about his car in LS1Mag? Last name is Lavoy...

http://www.youtube.com/watch?v=aGyL615C2Lg

Also look in "Hot Rod Magazine" They tested a stock bottom end 4.8 achieving 1200HP..

4.8

118 octane race gas

Twin 76mm eBay turbos

Cam

Ported heads

Arp head studs

Fast Intake and throttle body

26.8 psi for 1,203 hp!!! Still didnt go boom...

Made 60 Dyno Pulls and it never popped...

Seriously fella, he is not getting 28mpg out of a 8 sec, 700 whp car . If it were true, he should sell his secret to the major car manufacturers of the world. he would become an overnight billionaire.... after all, thats better MPG than my wifes Toyota Rav 4

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I'm particularly interested in the frame of the vehicle in the OP...rather a large cutout for exhaust header clearance where the frame would do well to be its strongest to support that massive amount of hardware. Just sayin'... The Camaro in post #26 should be quite a nightmare to tune too, if my understanding of the plumbing is correct. The turbos appear to be blowing through carbs perched on top of the Roots-type blower (under an apparently dummy injector hat) but it would seem that all the boost from the turbos would blow out the front when the throttle butterflies open. Those fancy S-curves coming out of the turbos are big flow-killers too. Someone please correct my understanding if I'm wrong here.

I was just looking at the camaro again and the intake on the turbos is plumb to the injector hat. So there shouldn't be a pressure drop

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I was just looking at the camaro again and the intake on the turbos is plumb to the injector hat. So there shouldn't be a pressure drop

So what happens to the pressure when the butterflies open??? Think like a manometer.

It blows out the front (it will ALWAYS take the path of least resistance, and it's easier to flow out the front than it is to flow through the restrictions under it).

Or correct what I'm not getting here, please.

EDIT: I completely and stupidly failed to notice that it was the intake side of the turbo compressors that is plumbed to the injector hat, so there will be 'suction' (negative pressure) behind the butterflies with the engine running, rather than positive pressure as I mistakenly wrote above. My apologies for my momentary lack of brains.

Edited by Ace-Garageguy
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When the butterflies open the airflow to the turbos would increase. I don't think that his setup is the best way to go, but he refers to his car as a trailer queen. SO I'm sure he doesnt mind restricting airflow to the turbos as long as it looks "good"

Duh...my dumb. I wasn't noticing that it's the intake side of the turbo compressors that's plumbed into the injector hat, so you're entirely correct.

Where does the output side of the turbo compressors blow? Into the manifold under the Roots-type blower?

Edited by Ace-Garageguy
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So what happens to the pressure when the butterflies open??? Think like a manometer.

It blows out the front (it will ALWAYS take the path of least resistance, and it's easier to flow out the front than it is to flow through the restrictions under it).

Or correct what I'm not getting here, please.

I agree with Ace - when I started racing my 2002 turbo I had big problems with the ducting from the t/c to the plenum chamber using some old hose we found - under boost, maybe .8 bar, it would find any weak spot and open it up and all the boost was gone, no matter which way the tubing was pointing. So that big old bugcatcher would actually become a bug deflector! Silicon hose fixed my problem, but the Camaro is obviously just for show!

I also missed the obvious, that the air from the scoop feeds into the turbos - but it looks like the air from the turbos goes up and in above the blower too! So that would still go back out of the bugcatcher. Or if it is fed back under the blower then the turbo might stall depending on how much boost the blower makes as against the turbo In fact at low reves the blower will blow air into the turbo, so the turbo might never be able to overcome that and may never spool up at all!

Edited by DonW
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I agree with Ace - when I started racing my 2002 turbo I had big problems with the ducting from the t/c to the plenum chamber using some old hose we found - under boost, maybe .8 bar, it would find any weak spot and open it up and all the boost was gone, no matter which way the tubing was pointing. So that big old bugcatcher would actually become a bug deflector! Silicon hose fixed my problem, but the Camaro is obviously just for show!

I have built 4 turbo cwrs and worked on many others. I have never ran hose straight from the turbo to the plenum. Maybe I misunderstood you. Another problem is you said some old hose. Well of course an old dried up hose isn't going to hold up under boost.

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The turbos blow in under the blower, which will only work if the turbos force more air in, then the blower puts out,

if the blower has more pressure , then the turbos, it will never work,, ( for looks, its cool, for real use,,i don't see how.)

blower_zpsd6e6bd7f.jpg

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I have built 4 turbo cwrs and worked on many others. I have never ran hose straight from the turbo to the plenum. Maybe I misunderstood you. Another problem is you said some old hose. Well of course an old dried up hose isn't going to hold up under boost.

On a 2002 turbo (as with most turbo setups) the pressurised air from the turbo goes to the plenum chamber (on mine, via an intercooler) and is mixed with the fuel and on into the inlet manifold pipes. I agree about the old hose! we used what we had and it wasn't good enough hence the new silicon hose which fixed it.

Thanks Randy for clearly illustrating what I was trying to get across!

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How would it not work? If the blower is compressing air and pushing it In the motor and the turbos are forcing even more air in after the blower I would think it would make crazy horsepower. More air more fuel more horsepower

The concept is that pressure isn't necessarily additive. IF the Roots-type blower is making, let's say, 20psi (pick any number, really...don't go arguing about how much boost a blower will make), and IF the turbos are only delivering air at say, 10psi, the 20psi will leave the intake manifold heading into the lower-pressure turbo impellers, and stall the airflow coming from them.

In principle (juggle the numbers as you see fit) a 20psi output from one airpump and a 10psi output from another airpump, both blowing into the same manifold, will not make 30psi. Maximum manifold pressure will only be equal to about the maximum pressure available from the compressor that makes the most boost.

COMPOUND turbo-supercharging (or compound mechanical supercharging) works, usually, because compressed air LEAVING one compressor (either the turbo or mechanical supercharger) is fed into THE INLET OF THE OTHER compressor, which raises the pressure even more.

Edited by Ace-Garageguy
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i understand if the turbos are after the blower, but they are before the blower. So the turbos are sending compressed air into the blower. Which is compressing it along with fresh air. I'm not saying its going to make a million pounds of boost. But it will make more togeather than either setup alone. There's a guy around here with a compound turbo eclipse. He is running a 16g turbo feeding a hx40. Last I heard he was running 65 pounds of boost. Now there is no way either turbo can push that much boost seperatly. But togeather they can

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i understand if the turbos are after the blower, but they are before the blower. So the turbos are sending compressed air into the blower. Which is compressing it along with fresh air. I'm not saying its going to make a million pounds of boost. But it will make more togeather than either setup alone. There's a guy around here with a compound turbo eclipse. He is running a 16g turbo feeding a hx40. Last I heard he was running 65 pounds of boost. Now there is no way either turbo can push that much boost seperatly. But togeather they can

If you look carefully at the photos and the illustration of the Camaro (which I failed to do earlier) you'll see that the turbos are blowing into the manifold AFTER the blower. They would have to be blowing into the inlet side of the blower (the top) to have the effect of raising pressure above what the blower is capable of delivering when the intake side of it is at atmospheric pressure.

Properly plumbed compound turbo-blower. Air filter to turbo compressor, to blower, to intake manifold. Yes, as you say, THIS setup will raise boost considerably.

3291570033_large.jpg

Edited by Ace-Garageguy
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