Twin Turbo on a budget? Help me think.

Okay -- bear with me. A little newbie dreaming here. I'm DEFINITELY missing some key components, but if they're not here I don't know what they are.

I heard mention of someone doing a twin turbo conversion on their WRX... is this just really complex, or is it a straight-up bad idea? If not, what would I need for this? I have a 2004 WRX wagon as raw material. I've added some suspension upgrades, but that's it.

The main GOAL: Hook up a small turbo for low-RPM power, essentially erasing turbo lag.

As a basic thought experiment, I'm considering the VF11 turbo and the stock TD04 as the snails. Here's what I've thought of so far. I'd appreciate it if those of you experts could fill this in for me.

The (hypothetical?) SHOPPING LIST:

short ram / cold air intake (since I don't have one already)
VF11
low-threshold wastegate (4 PSI? idunno what I'm talkin about)
boost control solenoid
aftermarket 3" turbo-back exhaust to help airflow & power?
aftermarket injectors????
aftermarket fuel pump???
lots of piping and creative use of underhood space...
and finally, a PRO TUNE

The (hypothetical?) schematic:

short ram / cold air intake ---> VF11 ---> stock top mount IC ---> TD04 ---> aftermarket front mount IC ---> engine intake (stock 2.0L for thought experiment) ---> exhaust

Obviously if I wanted to really take this all the way I'd swap out my engine for the STI block, slap on some new headers, get everything ported & polished, and use a giganto ball-bearing turbo for my main snail. BUT I will never in my life have ten grand to put into this.

Is there any way I could do this project for under $2000, labor excluded? Basically the whole reason I'm considering this is that I've seen VF11's go for well under $100 used, and since they're clearly not an upgrade to the TD04... why not just add on?

 

talk about lag

 

Twin Turbo and Budget belong nowhere near each other in any sentence.

Factor in some major internal fabrication and remodeling, custom tuning, and all sorts of other hardware... To do it right and not destroy a perfectly good car you'll need to think at the 5-digit dollar signs.

 

Okay sweet. So, basically the next time I win the lottery. Good stuff. At least now I'll have an answer in case people ask me what I'm going to blow all that money on.

 

not trying to be a **** but this would be way over your head. there is no need for a twin turbo set up on a 4 cylinder. the amount of money it would take to get it to work, you could buy two sti'. your price range isn't enough to make a wrx fast with bolt ons. the ecu that you would need to make it work would be 2000$.

my advice is if you don't want lag go buy a v8

 

Alright sounds good. If anything it's tremendously valuable having a concrete excuse to stop dreaming about it. :biggrin:

 

more does not always mean better! listen to these folks

 

get a 6cyl subie motor and then twin that sucker, but get ready to drop a grip of cash to get it running.

just grab a 16g for your wrx and call it a day

 

Is turbo lag really that bad that you wanna commite sucide?

 

i dont know about you but i will never drive a car with turbo lag! god i hate it!

 

vf11 and td04 lol

 

I feel like writing a bit of a manifesto on a twin setup, so here it goes, a concrete example for you to dream about.

The most common twin setup is in parallel, or same size turbo off each bank. Because you're looking for a low rpm turbo to minimize lag and a big-booster for high-rpm boost, you'd want to go with an in-series style setup...

...which is a massive bitch to get right, but the most rewarding in terms of boost if you nail it. Here's what I'd run:

1. TD04 externally WG
2. GT30r externally WG
3. TIAL 'gates
4. 1000cc injectors
5. 255lph pump (perhaps two)
6. Methanol injection for safety room.
7. V-core setup to minimize air travel distance and reduce lag when rolling up the 30r
8. More custom exhaust piping than you can shake a stick at (no EWG dumping to atmosphere in this magically setup)
9. More custom intercooling piping that you can shake a magical stick at.

Here's how I'd run it:

Headers into the TD04/TD04 EWG. The TD04's EWG runs 9psi mechanically. When the TD04's EWG opens it dumps into the hotside of the GT30r, running a 20psi EWG. Both the TD04 and GT30r pump the boost into the V-core, the V-core into the intake plenum. Meth keeps the car running north of 100octane on pump gas...

...and you're running peak torque from the TD04's 2400rpm rollup to the GT30r's 20psi at redline.

The only problem I can foresee is keeping compressor surge out of the TD04. Run a good BOV/BPV and tune the throttle to stay open no less than 15% (to injest any air that may get by the BOV/BPV after an on-boost liftoff), wham bam thank you ma'am you're running a near no-lag setup.

Thoughts? You could probably get it all done by a pro shop, fabbed and all, built engine, the works, for 25k. Boost is all mechanical to simplify tuning, too, mitigating the need for the world's craziest ECU.

 

so what you are sayin is that this could be done in a weekend right? haha.

 

Screw that just get 2 engine's....

 

I gotz ur twin turboz right here......for less than $20!!!




























[youtube]md_Av9rUuEw[/youtube]

 

enough!!!!

 

haha...lol

 

With the Vermont Sports Car team in tow, sure!

 

don't forget my favorite:

 

WTF?!??! Seriously? :ugh: :ugh:

Boy, these and some painted on "Brembo's" and you'd have a REAL ricer on your hands.

Actually, I've heard of this website. Rumor is that the government is considering enacting reproduction regulation laws, and this is a data collection web site. Anyone who buys this "turbo" kit will not be allowed to reproduce. Ever. Period. It's for our future. (j/k)

 

Well, if you really hate turbo lag get a 2.5l block and run your vf11, gawd that would spool quick!!!:laugh::laugh::laugh::laugh:


and cost less:biggrin:

 

Love the Japanese narration!

 

let me say though... I like the way you think about doing diy stuff on a buget!!!

I think it's a cool idea, but you could easly go down the pathev eryone else seems to and go rotated for big power....

.... but you sir, are more of the trail blazing type, and I can respect you for that.

 

OT but 2 weeks ago, when I had a vac leak, my car popped up a CEL, check it and it was some twin turbo CEL, LOL
wierd

 

Build a 300awhp NA STi. 13:1 compression, 9.5k redline, 200ft/lbs of torque...

 

y0 homie, honda be dat way ------>
not here :laugh:

 

Note that I said I wanted a "concrete EXCUSE for me to STOP dreaming about it." Check it... :hsugh:

In all seriousness, though, I enjoyed your post. I'll be shooting for that 25k mark in my WRX savings account. ...right after I buy a house, have kids, put them through college, and retire. :biggrin:

Thanks, putz. Apparently everyone else missed this part of my original post:

:laugh::laugh::laugh:

 

You will not make a whole lot of power that way. The TD04 will choke the motor out either way you look at it. That and your flow will be all messed up and not following a smooth path so the 30r will come on really late, if at all. Don't forget that heat has more to do with spoolup than you think. With another turbo that late in the system and all that crap in the way, you essentially have a big heatsink in front of the turbo you really want to come on.

A GT3076R with the twin-scroll .78 housing spools up very nice, and supports up to 550bhp. There is absolutely no reason to put some dinky turbo in front of it, screwing everything up.



On an agressive setup, mechanical boost control is a bad idea. You end up with serious variances in your boost between gears. I've seen 5psi higher going from 4th to 5th and that was on a 6 speed.














I don't understand all this whining about lag with a middle-of-the-road turbo. A 30R doesn't have much lag at all. You also have a manual transmission to be in the rpm range you need. If people can't handle that, then get a damn V8 with short gears.

 

some one got the crankies?

pissing in peoples wheaties much lately?

(your right though.... )

 

Here's another great idea, just run your exhaust into your intake manifold...

 

but...

and...

ow...

head hurts.

:ugh:

 

Do you plug your powerstrips into themselves, too? :biggrin: