Tt Manifold

[MiKa]

Ok so you have a car with huge power from a big single turbo, down the strip it would haul ass but as a daily driver (I think that's Pats intention for his project) it would be a pig untill it makes boost which would he higher in the rev range.. If you had twins it would spool up faster and be more responsive down low.. It would be a better car to drive.. But wouldnt be the quickest down the strip...

It all depends what you want the car for...

[senna_T]

The drag times will have alot to do with the gearing, but wither way it will be quick donw the strip becasuse it would have 400+ rwkw

[ETM]

2 turbos

2 dump pipes

2 screamer pipes (plumbed back twice the hassle)

2 air inlet pipes

2 air filters

2 cooler pipes

2 oil feed lines

2 oil drain lines

4 water lines

in short it will cost double and be a major pain to work on.

I seriously considered doing this to my ute but decded against because I like a setup that is easy to work on, not an engine out to replace gasket type setup

[lapdog]

You can get serious grunt out of one turbo so I dont see the need of spending twice the cash either

[6BOOST]

Ok so you have a car with huge power from a big single turbo, down the strip it would haul ass but as a daily driver (I think that's Pats intention for his project) it would be a pig untill it makes boost which would he higher in the rev range.. If you had twins it would spool up faster and be more responsive down low.. It would be a better car to drive.. But wouldnt be the quickest down the strip...

It all depends what you want the car for...

Perhaps you should go to page 1 and read my previous post. I have done EXTENSIVE testing of twin vs single turbo setups on RB26's, and for instance, a single GT35 kit on a STOCK RB26 with cam gears, exhaust and fuel system, made full boost at 4000rpm, and 378rwkw on 19psi of boost. The same car, previous to my GT35, had the same setup with a set of twin 2530's. On 21psi, it made 338rwkw and full boost at 4500-4600rpm. that's a gain of 40rwkw and 600rpm of spool.

Against twin 2540's, they made full boost at 5000rpm, and 376rwkw on 21psi, same car with GT35 kit made full boost at 4k and 397rwkw on 21psi. Trust T518Z twins on R34 GTR, full boost at 4700rpm, 300rwkw on 18psi, switch to GT35 kit and made 313rwkw on 16 psi, full boost at 3800rpm.

I could go on all day, but these are some of the fastest spooling turbo's avaliable in twins for the GTR, even the STOCK twins make full boost around 4200rpm, the single eats it all day everyday for power and response. For a last example, a built engine that could handle some boost we fitted a TO4Z to, full boost 4600rpm, 680rwhp on 28 psi...... Still think twins are the way to go??

As I previously said, feel free to be different, but the age where twins made boost earlier than a single are long gone, use a well designed merge style exhaust manifold with a correctly matched single, and I promise you it will win hands down in power and spool everytime. Maybe I'll test it sometime this year on a 4 litre just to prove it:-)

Cheers............................6BOOST

[senna_T]

6BOOST, do you think it would be different on the 4L considering each turbo would be driven by exhaust gases from 2L worth of engine versus 1.3L on the RB26? I tend to think this would make a big difference.

Its all about being different these days though, with a car modifying scene that is so large there really isn't that many things that haven't been done. I think that a twin setup on a BA would turn heads and have a massive torque curve.

[6BOOST]

Well, torque in a 4 litre is a function of 3 things, boost, total hp, and rpm. To explain, the higher in the rpm range you make peak torque, the less torque you will make. Now in saying that, the more power you make, the more torque you make, so there is a balance. Best example would be, that if we take 2x XR6's, both with 450rwkw, one has a laggy setup and makes full boost at 3500rpm, the other has a responsive setup and makes full boost at 2500rpm. The one that makes full boost at 2500rpm will make far more torque than the one that makes full boost at 3500rpm, as the fords natural torque peak is very low, and it generally makes peak torque at or just after 2300-2500 rpm.

If you run twins, and they make full boost any later than what a single would, and make the same power, then it will be LESS torquey, and be slower. The most responsive setup you can run for any given HP target is the one you want on your engine. In the case of smaller engines, this can be a little different, as a small engine may require a LOT of boost to make big power, and some small turbo's aren't designed to be efficient at 30+psi, and this is where knowing what your doing is of great benifit, something many years of experience and 1000's of manifolds has helped me with.

I personally don't think pair of smaller twins will be better than a single, I think at best, it will be AS GOOD as a single, and you'll be swearing about how much of a bitch the setup is because of limited room with all the components Leigh listed, there's a lot of sh it in there with twins. To give you some insight though, seeing as how we are talking about spiltting the engine in 2 to factor in turbo's.... A T28 disco potato doesn't make full boost on a sr20 until 3600rpm, and I'm yet to see one make more than 230-235rwkw. A GT3071 makes full boost on a 4 into 1 merge collector manifold at the same rpm as a 3076, and with the small .63 rear, these are hitting full boost around 3900-4000rpm, and we have seen 296rwkw on 109 octane fuel.

To bring that back to a 4 litre, twin disco potato's would make full boost around 3600-3700rpm, and max out around 20psi and 460-480rwkw. In comparison, a TO4Z will make full boost on split pulse merge style manifold at 2700rpm and 440rwkw thru an auto on pump fuel and 20psi or less, hopefully one of my customers send me a dyno graph this week of that setup. A GT42 or T51R setup would make full boost at 3600rpm like the twin disco potato's and have the potential to make mid to high 500rwkw's, one of my RB customers has gone 613rwkw on a single GT42.

Again, if the goal is to be different, I completle agree, my arguments are not in any way based on looks or individuality, or a judgement of you or those that would like to go twins, I am just putting forward the performance +++'s and - - -'s from experience so that those reading can take it in and maybe help make a decision on what they would like to do that best suits their needs:)

Cheers...........................6BOOST

[turbotrana]

In Snorts ebay add he states its made out of schedule 10 steam pipe and if so the manifold should hold together but if actually made out of 1.6 or even 2mm chinese S/S it will crack.

Either way I wouldn't bother with twins, too much of a headache for no real benefit in a straight 6.

6boost have you had much experience with sched 10 S/S and turbo manifolds. I notice you stick to sched 40 steel. I've made turbo manifolds out of both and if there was a schedule 10 steel this would be my preference but ATM seeing how well the sched 10 316 S/S is holding up.

[Dirty32]

Well - you sound well clued up to make an informed decision 6BOOST.

For the sake of being different I think its a great idea Senna... I love the idea of a twin setup but I personally wouldnt put my money up to try seeing the results that we are on the single setup.

If I owned a twin JZ or a twin RB26 and it wasnt so costly, not a problem with upgrading for the money.

But as I say, id love to see you do it and I think it would be an amazin head turner. It is after all people that try new things that make the custom car game what it is and also provides innovative ideas that lead onto new things / technology...

[DUS12]

what about a swanko special on one of your manifolds kyle lol