Parallel conversion

[leggyfreak]

thinkin of doing this and im just wondering whats involved in doing this

*ninja edit of spelling - Dog*

[subieboy]

As in parallel turbo??

Dont bother, better ways to waste your money...

[ReubenH]

New turbo's, aftermarket headers, new exhaust, single turb ECU and probably some more shit. I'd also consider an aftermarket ECU, so you can ditch the AFM, and that restrictive TT intake. I would imagine it's very similar to a single conversion, only with much more expensive parts (i.e $1000 zaust manifold instead of a $50 one) - as subieboy said, not worth it, especially considering it's so similar to a single turbo - you may as well just run a single turbo.. Running the stock TT in parallel is just fail because of the restrictive nature of the stock setup (all the valves everywhere).

May be possible on the stock turbo's, but you only have a wastegate on the primary. IIRC there are one or two secondary's that actually do have a wastegate though, can't actually remember though.

[subieboy]

 ReubenH said:

New turbo's, aftermarket headers, new exhaust, single turb ECU and probably some more shit. I'd also consider an aftermarket ECU, so you can ditch the AFM, and that restrictive TT intake. I would imagine it's very similar to a single conversion, only with much more expensive parts (i.e $1000 zaust manifold instead of a $50 one)

- as subieboy said, not worth it, especially considering it's so similar to a single turbo - you may as well just run a single turbo.. Running the stock TT in parallel is just fail because of the restrictive nature of the stock setup (all the valves everywhere).

May be possible on the stock turbo's, but you only have a wastegate on the primary. IIRC there are one or two secondary's that actually do have a wastegate though, can't actually remember though.

It is no where near similar to Single - Waiting for the Lag would kill you...

You could cook a BBQ while waiting for the turbo's to spool up and have time to play a couple of rounds of golf, Footy, and Back Yard cricket...

Oh and watch the paint dry...

Its like this, Foot flat on to loud pedal,

Jump out,

Cook the BBQ,

play games such as footy, gold, cricket et al,

paint the wall,

watch the grass grow,

watch the paint dry,

mow the lawn,

oh yea woot boost,

oh wait its only 7000RPM to 7500RPM

next gear do it all over again....

You could buy a the new BL/BP (2nd hand) for the coin you would waste...

There are ways to manage VOD... such as a sequential controller (see 41 - club sponsor)

[richm]

Re: parallel turbo conversion instead of twin sequential setup.

I have done this in my '01 GTB and it is the best thing since swiss cheese. I am no motor expert so I paid $400 for the conversion to be done by the professionals. Firstly there is no VOD at all, lag is very very small, fuel consumption has not increased and it goes hard! I mean, I now have two turbos working instead of just one. So far I have done 20000k with this setup and wouldn't go back. The only negative is that you sometimes get the 66 ecu error. This happens about once every couple of months. Not a biggie to me.

Anyway, just wanted to let you know of my experience with parallel turbo conversion.

[Joker]

dont knock it till you try it - as above said it can be an imrovement

you will find that anyone who says it is a waste of time gennerally has not had persoanl experiance DOING it, but have heard from a mate/read on the internet that its not a great idea

like a FMIC - alot of work for very little gain

and it is possible to do it without changing much over - some plumbing a stuff is all

I haven't done it either

[Guest keltik]

Ive driven a car that was converted to run parallel VF10's cos they were cheap. It actually ran pretty good but seemed like a complete waste of time to me when a single turbo conversion is easier

Gotta give it top marks for wank factor tho

[ReubenH]

One thing you can't forget about running twin parallel is that.. well, you're running 2 turbos on one engine. That is, you're halving the exhaust gas to power each turbo. *I can only speculate on this*, but it seems very inneficient to me. At the end of the day, if your 2 turbo's match the same flow rate as a single large turbo with the same ammount of lag, there's simply no point in wasting all that time and money on twin.

Does someone want to point out if there are combinations of turbo's that flow better and lag less? or is running twin simply for massive top end power?

[Glen]

Reduced rotational inertia of two smaller turbo's allows for quicker spool.

[Carbon]

"That is, you're halving the exhaust gas to power each turbo. "

And with a subby running cheap parallel, you are running all the gas from 4 cylinders via the first turbo then the second as opposed to (a more efficient) running the gas from 2 cylinders via each turbo. Still a plumbing nightmare..... Single is cleaner. I wouldnt knock it, but theres more knowledge around tried and true tuning for subbies in single turbo mode. But it you just want to be different, dont let us stop you :-)

[Guest keltik]

Didnt opticals prova legacy put down something near 220kw atw in parallel?

[Optical]

put down 245 at 18psi. Would have been fun to see how much more it could make if it had had forged pistons :-[

[Carbon]

 

"I am no motor expert so I paid $400 for the conversion to be done by the professionals. "

I wouldnt dare compare that to Opticals ;D

$400 will buy you a cheap parallel thrills, $$$$$ + prova will get you 245kw

[subieboy]

 Carbon said:

 

"I am no motor expert so I paid $400 for the conversion to be done by the professionals. "

I wouldnt dare compare that to Opticals ;D

$400 will buy you a cheap parallel thrills, $$$$$ + prova will get you 245kw

Yar but then us mere mortals don't have that kinda coin (like Prova itself) to throw at show case models as part of their marketing budget...

If you have the coin, doing a single conversion would be bettererer...

I drove a Parallel conversion a while ago, did not like personally... (but then again they kept the factory turbo's)

[leggyfreak]

hmmm think i mite just sort out a single turbo after reading thru this

[ReubenH]

Yep, opticals is a beast. I would NOT complain about that setup

Gotta pour allot of money into a twin parallel to make it better than a single though

[leggyfreak]

yea not to keen on pouring that much muny mite just find a single turbo motor and things and dump that in sounds alot easier

[ReubenH]

It's not even that hard, have you read that conversion thread i wrote? Basically you take your turbo's off, and stick a single one back on, and find an ECU to go with. It's been done in a single weekend.

[99GTB]

I had my 99 gtb running in parallel with factory vf26/27 turbos, aftermarket headers that I had lying around to try out, v5 sti ecu, 2.5" TBE.

Spooled roughly 3500 - 4000rpm. Had exhaust leaks so this wouldn't have helped.

Couldn't run over 12psi because I had a fueling issues and detonation but that was faulty fuel line.

Driveability of a single turbo. I did like it and appeared to be similar power as before but different power delivery which was nice for a change.

[leggyfreak]

well if thats the case i could have a busy weekend coming up

[leggyfreak]

just read your thread but the pics wouldn't load up u wouldnt happen to have a hard copy that u could email to me would you?

[ReubenH]

Yeah sorry, the pics will be back on the 16th.... bloody photobucket and it's bandwidth restrictions

And no i don't have a good copy, just a plain text copy. I can re-host the pics elsewhere if you want.

[leggyfreak]

yea that could be good thanks

[Guest]

 ReubenH said:

One thing you can't forget about running twin parallel is that.. well, you're running 2 turbos on one engine. That is, you're halving the exhaust gas to power each turbo. *I can only speculate on this*, but it seems very inneficient to me. At the end of the day, if your 2 turbo's match the same flow rate as a single large turbo with the same ammount of lag, there's simply no point in wasting all that time and money on twin.

Does someone want to point out if there are combinations of turbo's that flow better and lag less? or is running twin simply for massive top end power?

If anything its far more thermally efficient to go twin turbo on a boxer engine as you don't have the energy losses of the crossover pipe. Theres a company in german that makes a few twin turbo boxer

Altho the costs of extractors etc is the downside of a twin system the upside is there alot of cheap turbos to make lots of power.

If you want to run massive top end power a single is the best way to go.

[Guest]

ive been working on my parralle system for a while,

ran very nice with vf18's both internally wastegatted, coustom manifold and uppipes and a link to get the tune done.

taking it a bit ferther now, have stripped off the turbos for new one that are coming. and some other little bits, i really like the twin setup

-smurff