Twin turbo? [Merged 11-6]

[clownface]

Originally posted by OneFastGST
Are you sure that is a lambo??

It sorta looks like one to me 2.

 

[OneFastGST]

alright.


> Lambo

 

[EclipseGST-95]

yea that was my original guess...its got those classic side intake vents....that dont look like they have a purpose on this turbo set up cus the intakes are infront of that but i dunno

 

[kpt4321]

Originally posted by Redpest850
If you can do it....i think the best way a twin turbo setup is to have one smaller sized turbo and one huge one. SO at acceleration the small turbo will boost the car and the big turbo will take the backseat, then when higher speeds are achieved, the small turbo will spool up the bigger turbo, so the smaller turbo will wait as did the bigger turbo at the start. Then the bigger turbo will take over and bring your car to very high speed. That's what i've heard would be best for twin turbos....have a small turbo for better acceleration, and have a bigger turbo for higher speeds. Thats' what i think..

It doesn't work like this at all. The small turbo and big turbo are not for different speeds, the small turbo simply exists to add power until the big turbo spools.

 

[Tecson]

Originally posted by kpt4321
It doesn't work like this at all. The small turbo and big turbo are not for different speeds, the small turbo simply exists to add power until the big turbo spools.

Isn't that what was said?!

 

[Tallen]

Find some stocker 3kGT turbos (9b..right?)...those may make you very happy.

 

[JiveMasterT]

your main problem is going to be getting those turbos to spool since we have such a small motor. slap two t25s on an LT1 and you will have no problem... oh well. you could also try using a nitrous setup to get them to spool, but that sounds pretty insane, and i dont know what the hell im talking about so im going to stfu.

 

[kpt4321]

Originally posted by Tecson
Isn't that what was said?!

No. He said that the small turbo was for acceleration, and the big turbo was for top speed:

Originally posted by Redpest850
have a small turbo for better acceleration, and have a bigger turbo for higher speeds.

 

[96boosted]

I imagine the exhaust can be set up sequentially using a "wastegate" sort of approach. You have the exhaust going to the small turbo, then a seperate passage for the big turbo. Once the the car hits a certain speed/rpm the wastegate opens, and the exhaust goes to the big turbo. While this sounds like the same idea everyone else proposed, I was thinking of a sliding (or rotating) door for the wategate. The door will be 100% open for the small turbo, then as speed/rpm picks up, the door slides (or rotate) to open up the passage for the big turbo as it closes the other. The small turbo passage would gradually close 90% 80% 70% etc, and the big turbo passage would open up gradually, 10% 20% 30% etc. This way, the "extra" exhaust that are usually dumped thru the wastegate because the small turbo won't be needing it at high rpm, would be used to spool the big turbo gradually. Eventually the small turbo would be "shut off." This eliminates the problem that MKIII supra's have, a lag during mid rpm. I do see one problem though, the big turbo will probably push the the air back thru the small turbo's outlet because they're connected together.

-96boosted

 

[Enigma_Man]

Well, I think this whole thing is pretty silly

Twice the weight, half the spool, for only 2x (roughly) of (pick one) pressure, or flow (sequential gives more pressure, parallel gives more total flow). Bleh!

But... I had this idea while thinking about all of this, if someone was hell-bent on doing a twin-turbo thing.

If you want to go with a tiny turbo and a large turbo (which seems to offer the only benefits at all of doing a twin-turbo setup) could you run a tiny turbo off of 2 exhaust runners, and a big one off of the other two? (or tiny off of 1, and big off of 3?). All of the intake outlets would go to all 4 cylinders.

Wouldn't this let the tiny turbo spool up reasonably quickly, which would help spool the large turbo to provide more CFM at higher pressure? You'd still be cutting yourself down in the amount of cylinders though...

Oh well, I guess it's all just a bad idea, hehe.

-Jesse

 

[szewczyd]

I am so glad that I decided not to buy this project when I had the chance. Would have been a total waste of 500 bucks, oh wait I could have found some HONDUH kid and maybe have made a killing, but I ain't like that.


Oh yeah good luck with it can't wait to see it.

 

[kpt4321]

Originally posted by Enigma_Man
Twice the weight, half the spool, for only 2x (roughly) of (pick one) pressure, or flow (sequential gives more pressure, parallel gives more total flow). Bleh!

Jesse, keep in mind that we're not talking about a twin-pas diesel sort of sequential setup here. We're talking about a twin turbo setup where the intake really only passes through one turbo, it just depends on the condition as to which one it goes through.

For slightly more weight (no more than 50 pounds) you gain insanely fast spool (I'm thinking full boost around or before 2500 rpm) and you still get the crazy top end pull of a 60-1 or larger turbo.

If you want to go with a tiny turbo and a large turbo (which seems to offer the only benefits at all of doing a twin-turbo setup) could you run a tiny turbo off of 2 exhaust runners, and a big one off of the other two? (or tiny off of 1, and big off of 3?). All of the intake outlets would go to all 4 cylinders.

Wouldn't this let the tiny turbo spool up reasonably quickly, which would help spool the large turbo to provide more CFM at higher pressure? You'd still be cutting yourself down in the amount of cylinders though...

You want the turbo to spool as fast as possible, so why not feed all four exhaust ports to it? You feed all the exhaust to a turbo smaller than a T-25, and get full boost ass early. Then, you gradually taper the exhaust flow over to the larger turbo, so that it takes over around 3500-4000 rpm or so (I would need to work this out, obviously). Then for another 4000 rpm, you're basically running thr big turbo only, just like a high power DSM.

It would feel like your "average" 500 whp car, except with twice the torque under the curve. That makes for a car no slower in the quarter, and a hell of a lot more fun in the city and on the highway and such.

 

[clownface]

Im not that familiar with Twin turbo. How would you get the exhaust flow to change over like that? Are there any cars that are already set up like that out of the factory?

 

[IMMORTALSPYDER]

Originally posted by clownface
Im not that familiar with Twin turbo. How would you get the exhaust flow to change over like that? Are there any cars that are already set up like that out of the factory?

Mazda RX-7 for sure. Not sure how other TT's work.

 

[clownface]

thats cool, just how does it work though?

 

[kpt4321]

Setting up the switch is the hardest part, and one of the main reasons why good sequential turbo kits are so rare and so expensive.

I've been brainstorming, but I really have no good ideas yet. A slider valve at the Y split would work, but that's not the more efficient way. An oversized "wastegate" on the smaller turbo might also work, but I would have to run the calculations on that one to se if you would get enough flow.

 

[Tecson]

I was thinking of th ewastegate idea too. If I can close up the larger turbo until the requires amount of pressure is reached it would open letting the exhaust gases start off the second, but for that to happen I'm going to have alter the entire setup. (which is going to suck). What do you all think?

 

[redturbo66]

Originally posted by clownface
Im not that familiar with Twin turbo. How would you get the exhaust flow to change over like that? Are there any cars that are already set up like that out of the factory?

the 300zx came factory with a TT

 

[jb talons]

I think you should do what YOU want to do. I think that way back in the beginning of the this thread you said you were just doing this twin turbo setup because you could and for some bragging rights. There are probably several good ways to set it up. You just have to figure out how to plumb it up.

I still want o hear how it turn out.

 

[project94tsi]

Originally posted by redturbo66
the 300zx came factory with a TT

yeah thats a twin turbo V6 one for each side of the engine i dont think it is a sequncial turbo setup like the TT rx7's and supras, im not sure though.

 

[clownface]

Originally posted by redturbo66
the 300zx came factory with a TT

i know alot of cars had TT, im just wondering about all the different ways they work.

 

[Red99GSX]

Originally posted by project94tsi
yeah thats a twin turbo V6 one for each side of the engine i dont think it is a sequncial turbo setup like the TT rx7's and supras, im not sure though.

no ZTT's are not sequential. they spool together. love those cars. i know a guy who has a ZTT and it has 630hp to the motor. obviously turbo upgrades, haha

 

[Damn 2nd Gear]

porsche 959 had a sequentual TT 4cyl... but it was also $230,000 and also AWD. ttop speed somewhere around 200 and a 1/4 time to match. im sure the exact times tho.

 

[clownface]

just how did it work though?

 

[Chrisab429]

So how many horses are you trying to get out of this thing? and do you have like an unlimited supply of money and time?
not trying to hate or enything, seems cool sombody is actually trying to do it. Are you gonna try and go for the multiple air filters? If so where are you planning on putting them? so whats gonna be up with the sensers, just through them out i guess.
Also with a duel exhaust and some duel themed exterior that would be bad ass!