twin turbos!

Post by **JESTER** » Mon Jun 02, 2003 7:11 pm

Makes scense. I will be looking forward to seeing this one completed.

I would love to go twin for the sheer purpose of there are no twin 240 running around. Like Mad said, Shock value.

Post by **Exar-Kun** » Mon Jun 02, 2003 7:11 pm

yes, it si complex from an engineering aspect, manifold construction, trim selection, and my biggest fears:

manifold thermal expansion, spacing issues,heat problems, and wastegate location problems(unless you use internal ones...)..

but hell, if I had a spare car and some weld-els and extra time, I might would try to do it just for S+G-chet

Post by **_dk** » Mon Jun 02, 2003 7:11 pm

TomsMR2- have you picked up the turbos yet? a couple of K03's off of VW 1.8T's could be worth looking at as well, as everyone and their mother is upgrading those too... cheap and i think they might be even smaller than a t25-

Post by **Mikel** » Mon Jun 02, 2003 7:11 pm

TomsMR2 wrote:
exar-kun: twin turbos arent complex. the "one large, one small" twin turbos, like supra TT's are complex, with bypasses etc etc.

Supra Twin Turbos use two turbos of the same size

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

I was pondering this myself a couple of months ago. A friend of mine has a few turbo "logs" off of his 3rd gen RX-7 sitting around. They are sequentially setup and are good for up to 400whp. The thing that interested me most about the setup, is the flexibility of the sequentialism, since the first turbo spools to 4500rmp, when the second one kicks in, and the car shoots off. It's very decent with only one of them working, and pulls very hard once the second one kicks in. I was considering just taking that log the turbos sit on, and making my manifold with a flange that would fit it, then fumble around with the 10-20 vacuum lines that the FDs turbos require and a few actuators, some other custom stuff, and voila, twin turbo setup on a 240. Then I thought that since it'd be my first time turboing a car, I'd better stick to a simpler, single setup. But the idea is still with me, and if someone wants to ponder it as well... be my guest. It won't be too complicated, but a little time consuming. Something to think about. The twins that the FD has are about the size of a t-25. Spool is great with no lag on a similar displacement engine (1.3x2 rotors = 2.6 liters). I am thinking of doing that in a year myself, when I’ll want a streetable 300-400whp KA.

Sil80

Post by **C-Kwik** » Mon Jun 02, 2003 7:11 pm

Ultimately, it seems like a waste to me. I haven't seen compressor maps for a T25, but I would imagine it would not be as efficient as even a T3. Unless the T25 has a better peak efficiency and the KA can manage to get to that point at half the flowrate(since it will be divided between two turbos), I see no reason to use two small turbos as opposed to one larger one. At least if making good power is an important concern.

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

If I were to run a twin setup, I would run independant manifolds and a pair of GT2510's or GT2530's. I've seen a GTR run 10's with a pair of 2530's and they still come on boost fairly early. But that would be on a daily driver and for the bling bling effect.

I seriously would only consider twins on a drag style setup where lag is just a shot of N20 away from disappearing. Again, could be done with a single easier and cheaper, but the wow effect is always cool, plus I don't think I've ever seen a twin KADET.

If anyone wants to try it, I'll be glad to build you a kit. I'd suggest a set of T3's with internal gates to keep the price down. If you want quicker spool you can always go with the BB option and add in another 800 bones.

Man, the more I talk about this the more I want to build one up.

WD

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

Nobody likey my sequential idea? Fine. You'll see! You'll ALL see!mwuahahahahaha!.... *sigh* I wish I wasn't broke....

sil80

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

LMAO....

Post by **TomsMR2** » Mon Jun 02, 2003 7:11 pm

sequential turbos is ALOT more than i want to think about.

mikel: im not too familliar with supra TT's, but i do believe they're sequential, regardless of size, correct?

wd: why individual manifolds? im not disagreeing, im actually interested in the benefit of 2 indi's vs 1 log with 2 flanges.

dispite nay-sayers, im going for it... if i absolutely hate it, i can just fab up a new manifold.. flanges are 50 bucks, and u-welds are cheap.

i know certain smaller trim T3's crap out hard on 1.6L 4age turbos.. so two of those should work.

im well aware theres no benefit to twin over single

Post by **Mikel** » Mon Jun 02, 2003 7:11 pm

TomsMR2 wrote:
mikel: im not too familliar with supra TT's, but i do believe they're sequential, regardless of size, correct?

Yep, turbo number one spools normally, number two comes online along with number one at ~4000rpms. Needlessly complicated in my opinion. This is where mine currently reside:

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

With log style headers, 2 individual mani's will be able to flow into each turbine better then a 4 chamber manifold flowing into 2 seperate turbines. It also allows you to move your turbine flange around on your mani without worrying about effecting 1 or the other turbines exhaust flow.

WD

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

Give me those twins, u ungrateful bastard! *L* j/k... I really want them tho, if ur gonna throw em out... I might just go through with my sequential setup idea. Can just two cylinders really power a turbo well enough? At not ridiculously high rpms?

sil80

Post by **C-Kwik** » Mon Jun 02, 2003 7:11 pm

WDRacing wrote:But that would be on a daily driver and for the bling bling effect.

I prefer Vroom Vroom over Bling Bling. Especially when Bling Bling thinks he got Vroom Vroom and I whoop on him...=)

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

Yeppers, its all about exhaust flow. You'll still have 1.2 liters per turbine to spool her up. I would definitly use BB turbines if I had the money. Course, you could always plumb in a 50 shot of anti lag.

WD

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

C-Kwik wrote:I prefer Vroom Vroom over Bling Bling. Especially when Bling Bling thinks he got Vroom Vroom and I whoop on him...=)

No way dude, Bling Bling mods are worth 15 more hp then Vroom Vroom anyday....pssshhhht.

Post by **C-Kwik** » Mon Jun 02, 2003 7:11 pm

WDRacing wrote:With log style headers, 2 individual mani's will be able to flow into each turbine better then a 6 chamber manifold flowing into 2 seperate turbines. It also allows you to move your turbine flange around on your mani without worrying about effecting 1 or the other turbines exhaust flow.

WD

Well, if you are referring to the Supra Manifolds, it is actually two manifolds bridged by a flex pipe. And because a sequential set-up requires that the exhaust gases from all the cylinders reach the first turbo, the bridge is necessary.

IMO, the Supra Manifolds are rather restrictive considering the great port flow the 2JZ-GTE has. I thought about trying to improve on it by making a custom log mani and turning it into a parallel set-up with some modified stock turbos, but I just took a good look at my friend's in his garage last weekend and there is very little room for a better flowing manifold while using the rest of the stock hardware. I still have yet to do some calculations and measurements on it. Too bad I don't have a Supra to put it on if it works...

Post by **TomsMR2** » Mon Jun 02, 2003 7:11 pm

sil80drifter wrote:Can just two cylinders really power a turbo well enough? At not ridiculously high rpms?

look at it this way..

"can 1.2L power a turbo"..

audi/vw turbos are TINY on their 1.8T motors. they're damn near full boost at like 2K rpm, its an obsurd spool... you'd just be using 0.6L less displacement to spool. i wouldnt be surprised if you could spool 2 by 3200rpm or so.

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

good point... ok gimme them supra turboes, right meow!

Here is my case for the RX-7 twins. They can be made to work with only 4 actuators (my friend has done it).Read this:

http://www.bimmerforums.com/fo...95920

All of it.

sil80

Post by **Mikel** » Mon Jun 02, 2003 7:11 pm

C-Kwik wrote:Well, if you are referring to the Supra Manifolds, it is actually two manifolds bridged by a flex pipe. And because a sequential set-up requires that the exhaust gases from all the cylinders reach the first turbo, the bridge is necessary.

IMO, the Supra Manifolds are rather restrictive considering the great port flow the 2JZ-GTE has. I thought about trying to improve on it by making a custom log mani and turning it into a parallel set-up with some modified stock turbos, but I just took a good look at my friend's in his garage last weekend and there is very little room for a better flowing manifold while using the rest of the stock hardware. I still have yet to do some calculations and measurements on it. Too bad I don't have a Supra to put it on if it works...

You can try it on mine

I can pull the turbo and manifold off in an hour

Sil80 - the stock turbos are wasted man, just good for cores really.

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

*sigh*... can I just superglue them to my headers and brag to people? I'll just say I'm not boosting, so the car feels stock... Btw, did you read the link? Is the supra setup similar in function? Manifolds look a little similar, so I'm wondering.

sil80

Post by **Mikel** » Mon Jun 02, 2003 7:11 pm

sil80drifter wrote:*sigh*... can I just superglue them to my headers and brag to people? I'll just say I'm not boosting, so the car feels stock... Btw, did you read the link? Is the supra setup similar in function? Manifolds look a little similar, so I'm wondering.

sil80

For all practical purposes, the Supra setup is identical.

Post by **Jays90240SX** » Mon Jun 02, 2003 7:11 pm

What happens when you put 2 T25's for example, on a LOG manifold. Meaning, on the SAME log that connects all 4 runners?

I know it can be done with some interesting turbo angles to clear the Master Cylinder and such, but why do we need to put 1 turbo on 2 cylinders, and the other turbo on the other 2 cylinders?

Am I just missing something here?

wouldn't 2 T25's boost quicker, and give great power at the same time, comparing to 1 bigger turbo, on the same manifold?

Post by **WDRacing** » Mon Jun 02, 2003 7:11 pm

You can put the turbines on ther same manifold, I was simply saying my method would flow better. No T25's will not flow better or boost better. I don't know to many T25's that can boost up to 30 psi. But you can get a single T3/T4 to come on boost early and push all the way to 30.

WD

Post by **prigo** » Mon Jun 02, 2003 7:11 pm

I wanna try it, but I'm gonna do some more research first :p

Post by **plastik240se** » Mon Jun 02, 2003 7:11 pm

cow wrote: I DO own a Honda after all.. :P

EVIL!!! EVIL!!! AAAAHHHHHHHHHHHH!!!!!!!!:twitch: :uzi2 HONDA :biggun:

Post by **plastik240se** » Mon Jun 02, 2003 7:11 pm

wow all this talk of turbo this and t3 this and rx7 that, makes my head hurt. think i might just stick with a n/a still i can get a big enough bottle of asprin.

Post by **McAdam** » Mon Jun 02, 2003 7:11 pm

well well well, if you all had read corkys book this thread would have died a long time ago..... two small turbos are NOT better than one single, besides teh complexity of the piping and what not, 2 turbos will have more lag due to FRICTION than one large one. Id you have a circle (like a turbine wheel) and you double the corss sectional area, you only have to multiply the toal circumfrence by about 1.5 times.

but I think the bling bling/vroom vroom factor comes into play heavily here. what you need are 2 VNT turbos. variable Nozzle Turbines. sound expensive, huh? not really. they came as STOCK equipment on 1990 shelby FWD turbo dodges. I got mine form a yard in texas for $150. I am goin with a T28 cold side for it tho and its going single style on my CA18.

I think the KA24DE could do it! just make sure the exhaust flows very good. might want to look into getting the exhaust ports ceramic coated. keeps heat in the exhaust stream and outta the head. And HEAT is actually what makes turbgos work.

I'm done yakking now, I'll just shut up and go back to the bar.

McAdam

Post by **TomsMR2** » Mon Jun 02, 2003 7:11 pm

if you read the thread... i stated already that i know 1 turbo is better.

Post by **sil80drifter** » Mon Jun 02, 2003 7:11 pm

yeh.... know it too...but I make it look like I don't.

sil80

twin turbos!

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