someone should try it

[Powerstroke Cowboy]

Na, basically the computer wants to see a certain amount of drive pressure, the vanes close in the turbo making more back pressure and boost from the high pressure turbo, once the pressure rises the vanes open and more of the exhaust energy is diverted to the low pressure, basically just kicks the high pressure in faster to get things moving first, once things get moving the exhaust is a little more free flowing.

Thanks!!! I got things twisted around a little!!!!!


Hey yall pretend I never said it>> LOL

 

[jdgleason]

I Think I said that wrong. the little turbo is feed by the bigger one. BUT after a certian point when the bigger turbo hit a certian amount of boost it skips the smaller one and blow right to the engine..

Correct me if i am wrong please dustin

I think I am all wet LOL

I should have kept my mouth closed..

Youre on the right track. Like dustin said when the vanes open, it diverts drive pressure (exhaust) to the low pressure. You have the right idea

 

[Erikclaw]

Thats the thing is it probably wouldnt continue to make 50 psi of total boost, (almost impossible to gate it that low i bet) so now you would be talking in the neighborhood of 75 psi, keep in mind this type of tripple turbo set up would be more geared for people needed to make big boost numbers to make power, a good flowing set of twins may only require say 65 psi to accomplish the same thing, but for a guy running bone stock heads with valve springs and push rods, this may be the way to get that extra air in the engine

I think I have my head wrapped around this now. Makes sense that it would now produce more than the 50psi of boost the stockers made alone and with the help of a bigger atmospheric they could be around 75psi or so.

 

[Dzchey21]

I think I have my head wrapped around this now. Makes sense that it would now produce more than the 50psi of boost the stockers made alone and with the help of a bigger atmospheric they could be around 75psi or so.

That is IF there is enough back pressure to drive the low pressure hard enough, but going back to what you said earlier about a stock injectored truck having to wastegate with a big tune, take that wasted energy thats going in the down pipe, and put it into a turbo, now that energy isnt just being thrown into the down pipe and wasted, its being used to flow more air.

 

[Dzchey21]

Ok im going to bed, i know i will have a earful from charles in the moring, but i would actually like his insite on the set up, but i think it would work

 

[Erikclaw]

That is IF there is enough back pressure to drive the low pressure hard enough, but going back to what you said earlier about a stock injectored truck having to wastegate with a big tune, take that wasted energy thats going in the down pipe, and put it into a turbo, now that energy isnt just being thrown into the down pipe and wasted, its being used to flow more air.

Because you wouldn't have to wg it since you are dividing the drive pressure between the three turbos and you can use that wasted energy that would have been gated out to drive the turbos?

 

[Erikclaw]

Ok im going to bed, i know i will have a earful from charles in the moring, but i would actually like his insite on the set up, but i think it would work

I know I asked more questions than anything, but I appreciate the answers from everyone in educating me in this. I hate the idea of having a modded truck and not knowing much about the way things work the way they do.

 

[Dzchey21]

Because you wouldn't have to wg it since you are dividing the drive pressure between the three turbos and you can use that wasted energy that would have been gated out to drive the turbos?

You still will have to gate it around the stock turbos, but now the exhaust energy is going into the atmospheric turbo, rather than just in the downpipe.

your right and wrong all in the same statement lol. You would have to wastegate the crap out of the stock turbos because they just cant flow the exhaust thru them, and the drive pressure would go thru the roof, same as say a 62/s510 combo on a cummins or a a3k/a8k that ats is starting to become famous for.


Think about it like this, your truck runs a wastegate still but instead of running the gate into the downpipe like your towpowers did, the gate now runs between stages like your new high power set up, the gate dumps from the high pressure turbo into the the low pressure turbo, since the exhaust wheel, and housing is bigger on the 76mm in your set up, the back pressure is still undercontrol, thus no wasted exhaust energy like stock/tow powers/ with a wastegate

 

[Jhaddox]

you guys just confused the hell outta me:morons:

but this does sound interesting and i still have stockers on my truck, and want another turbo set up this fall sooo maybe if someone cough *chuckles* cough can chime in and put their thought into this and explain the theory on it working/not working it'd be something that could happen instead of a new compound set up

 

[Powerstroke Cowboy]

I couldent agree more Dustin..

 

[Austin]

Sounds to me like it would work.. That conversation was sooo confusing, except for the MAP thing with pictures and numbers, that was good Dustin.

 

[Erikclaw]

Ohhh ok, I am getting it now. LOL To be honest I never understood exactly how my setup was gated but knew it worked. That makes perfect sense the way you described it. Damn I need to study more. I probably shouldn't have shared that.

 

[JAP]

Quick question. What size turbo are most running as a single?

 

[Nos_GTSR]

I thought about doing this 2 years ago with a gt47 but was told it wouldnt work but recently was told it would. I want to try this, just got to figure out where to put the 2nd gate if needed. Ill make a call and see if I can pull some strings and get a 88mm ish turbo.

 

[Dzchey21]

About 66mm is what wide opens single is. I had the best luck with an odd ball gt42 that had a 68mm wheel and a custom exhaust housing that was super tight. Not alot of singles out there right now. I know Maryland performance just did another truck with a bulseye 66 not sure how that truck turned out tho

 

[Smokin_Joe]

After reading this months DP mag, I had dreams of running a big boy in the bed...

 

[Powerstroke Cowboy]

From looking at all the specs a detales on this turbo, I think it would work good to feed the stockers.

http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT45/GTX4508_800270_1.htm

Bt then if you need a high pressure ratio turbo here you go..

http://www.turbobygarrett.com/turbobygarrett/catelog/Turbochargers/GT55/GT5533R_769115_2.html

 

[jdgleason]

After reading this months DP mag, I had dreams of running a big boy in the bed...

That was sick lol. Have you seen sts remote turbo kits?

http://www.youtube.com/watch?v=AG2j-G9V28g

They sound unbelievably nasty.

 

[Erikclaw]

That was sick lol. Have you seen sts remote turbo kits?

They sound unbelievably nasty.

Those kits have been around for a while. If I had a late model sports car that is the way I would probably do it. Stealthy. Just watched your vid, I have heard these before but never one that loud. Does sound sick.

 

[Charles]

Brilliant...

That's what this idea is.



I'll try to clarify a few points that seem to be circling this discussion.

1. With adequate wastegating the stock charger turbine section would be a non issue in terms of shaft speed and drive pressure control, just like when you guys gate around them with big fuel now.

2. The compressor side of the stock charger setup would not be an issue because.... now don't let your heads pop.... but the CFM flow into the stock chargers would actually decrease a good bit if you added another compressor stage upstream because you would lower the PR the stock chargers were acheiving and they would be doing less work than they did without the additional compressor stage.

Giving exact values for CFM flow takes a bit more time, and with 3 stages I just don't feel like it right this second, plus I don't have time right now, but.... showing the dramatic PR swings should make this clear without even really showing the expected CFM flow drop anyway.

In terms of PR, if you had a truck running the stock chargers at 40psi, and if both of those compressors were balanced, then each would be operating at a PR of ~2, meaning each would be making ~13-14lbs of boost.... loafing really.

Now what if you added say a GT47-88 in front, and you wanted 70psig on the manifold? What would each stage have to make? Well, for simplicity, lets assume they will be balanced stages for the moment, just to get a feel for where we'll be.

Well, balanced, with 3 stages making 70psig, each stage would be required to produce a PR of only 1.79...



That's not a typo! Each compressor would be making ~11-12lbs of boost with 70lbs on the manifold.

In other words, with a first stage compressor in the mix, the stock chargers would be working less at 70psi on the manifold than they were making 40 without help.

But truth is, you wouldn't want to run your atmosphere that low, and not take advantage of the bigger turbine, so you would probably make say, 15 to 20lbs with the 47 or 55 and then let the stock chargers just make up the other 21lbs between them. Is the stock setup pretty efficient at 21lbs of boost? Yep... and it would be just as efficient with a big single pumping up the atmosphere running into them.

And the required CFM flow through the stock chargers and heads would be reduced, power per power compared to the stock chargers alone given the greater charge air density from allowing the stock chargers to flow a heavier media at a lower pressure with a first stage compressor pumping up the density upstream.

Three-stage compression with two of the stages already in place...... I like it.... a lot....