Single Turbo Upgrade To ~300awkw

[bigmikespec]

Up in the higher rpm's where the lack of exhaust gas is not an issue it all comes down to the intertia/weight of the wheels ability to accelerate faster.

Yes but the same can be said for a single at higher rpm where you have double the flow rate of gasses to accerate larger wheel. Note I said a larger wheel and not a wheel, double the size. Personally, I am not fussed either route to make 300-350kw I just want to take which ever route is better (in the future some time), from an efficiency stand point.

To me, a single eliminates trying to merge high velocity gas streams (and if you have seen what it looks like in slow motion using fluid mechanics techniques you will cringe), elimates heat transfer from the front turbo to the inlet of the rear, gets rid of pressure losses from extra piping and is not so crammed especially when you have big ham fists like me.

Who started this thread? Man, just go the small single!

Mike

[Cubes]

There must be some credit to using the twin route as Nissan would not have wasted countless $$ on doing so.

My own experience with two similar sized setups the twins did make their peak boost 'slightly' later, came on smoother BUT had noticeably improved response when going from zero throttle to full throttle once over 4000rpm.

[bigmikespec]

There must be some credit to using the twin route as Nissan would not have wasted countless $$ on doing so.

My own experience with two similar sized setups the twins did make their peak boost 'slightly' later, came on smoother BUT had noticeably improved response when going from zero throttle to full throttle once over 4000rpm.

Whether countless $'s were spent or not, no one can confirm that. Yes there are reasons, one may be for marketing purposes, probably among other geniune reasons (from a performance/efficiency standpoint), but there are obvious disadvantages in comparison with a well designed single set up.

Anyway, Cubes it is good people can discuss things like this without getting personal and/or frustrated and say something stupid. So thanks mate. Are you an Adelaide boy? Might see you around.

Mike

[__PhaseShiftDown]

Keep the input coming guys :-)

Also, how much more work are we talking about converting to a single?

[Cubes]

Its all good Mike.

Adelaide I am.

Keep an eye out for a stock black R32, near stock ride hight stock wheels with a little 3" tip poking out the rear with a exh. note not quite right.

---

Going to single.. Additional cost of a nice exh manifold, ext. gate, new dump pipe and new inlet and IC piping. It would add up fairly quick. Definitely not worth the hassle for under under 360ish rwkw.

[Johnny]

Trust greddy make that cool intake adaptor for 2 AFM's in polished s/s for a couple of hundred.

kits from hks etc are like 4500-5000 with everything; yen plummet makes it a tad more expensive.

I was sooooo keen on a single t04z but i keep reading horror stories from EPA which would make my life hell when there is a big huffer in full view of the police.

[bigmikespec]

Its all good Mike.

Adelaide I am.

Keep an eye out for a stock black R32, near stock ride hight stock wheels with a little 3" tip poking out the rear with a exh. note not quite right.

---

Going to single.. Additional cost of a nice exh manifold, ext. gate, new dump pipe and new inlet and IC piping. It would add up fairly quick. Definitely not worth the hassle for under under 360ish rwkw.

Will do man, if you see a stock looking wine red R33 GTR Vspec that is me.

I agree with your last statement too!

[juggernaut1]

Str8e180's setup with GT35 with ATP .78 divided housing on a divided manifold and you get this:

Edited October 30, 2008 by juggernaut1

[R31Nismoid]

^^ I've twins are better than that with the same power

But then someone could probably bring a better single graph and so the story goes

I agree with Cubes for the most part on the points... although the -5's are now making nearly 400rwkw now... so i'd say revise 360rwkw with 400rwkw

The twins are only about $500-$600 more expensive than a single Garrett (which is pretty interesting)

But the money is saved when you factor in manifold and oil/water line costs and so on.

Long term, single would be cheaper from a servicing point of view (should you need to get it off more than once)

Twins are a mega pain to take on/off... so doing it more than once would bring the single infront from a cost point of view

wrong, stock blocks are known to split with around 300rwkw... want proof? i have one at home

yours also wrong in regards to the twins, it has been shown that even a t04z well set up will have less lagg than garrett replacement twins...

if 300rwkw is your goal i suggest a garrett 3076r or 3082r with a 0.8ish bum on a 6-boost manifold

You can split any block if you really want to try it.

Big RPM launches on sticky rubber, and you'll soon have that familiar coolant drip on the ground when you park it.

If you dont launch it hard, constantly etc, blocks will be fine.

There are that many people making over 300rwkw now on a factory RB26 block that any problems would be common as dog poo.

The more knowledgeable builders will make some changes to the block to stop this from happening, but there are a lot of backyard style builds who are only upgrading pistsons and similar without modding the block itself... And they hold fine is treated with some respect

[Beer Baron]

do a search in this forum for small single turbo or SST

there was a big thread on this topic (started by me) in the last year or so. I had a similar thought, why not try a mid sized single to aim for just 300-350rwkw. lots of good responses in there.

[blitzxtr]

Do know one thing ive seen standard blocks do 500awkw with proper prep.

think its all in the build & whos doin it.

[Beer Baron]

fark since i'm nice here it is. http://www.skylinesaustralia.com/forums/R3...ur-t139923.html

started nearly 2 years ago, but ran for a year. in the end I went silly and have ended up with:

tomei manifolds

HKS GT-SS

tomei dumps

HKS twin 75mm front pipes into single 4inch

greddy full suction kit

greddy hard pipe kit

ARC intercooler

single definitely would have been cheaper. I could get rid of the tomei mani's (~$1K), GT-SS (~$3K), tomei dumps ($700), Greddy suction kit ($1K), HKS front pipes ($700). that would leave $6400 to spend on a single set up (gate, mani, turbo, intake pipe, dump, front pipe, turbo to cooler pipe).

[discopotato03]

Where the twins have it all over singles is that most singles are single scroll - meaning one turbine nossle .

A twin scroll single achieves pretty much the same thing but requires one or preferably two external wastegates to control turbine speed - boost .

I doubt very much in the late 80's when Nissan was developing the RB26 that external wastegates even got a look in .

The next best thing is to run parallel twins with individual integral wastegates , it's the only way to keep the exhaust gasses seperate between the front and rear three cylinders until downstream of the turbos .

Either is whats required from a high performance turbo engine to get around reversion problems .

I'd say packaging was also an issue , I think it would be far easier to drop the shell over the engine/front subframe assembly on the production line with two small diameter turbochargers cuddled up close to the cylinder head .

I once though otherwise but the dollars and cents practicality on a road RB26 I think swing in favour of the parallel twins .

With a single you have to hope that the manifold you get is a good one and then there's the complexity and cost of external wastegate/s . Cops know what GTR's look like and often want a look under the lid - wouldn't you ?

If all they can see is what looks like a std motor they've got nothing on you . Explaining what those big HKS "EGR" valves are would be a bit more difficult .

The real shame of the twins is getting at them if you need to . If you do them once and do it right they should be fine after that . I reckon I'd be doing little things along the way to try and make it easier if there was a next time ...

Your calls , A .

[SimonR32]

^^ I've twins are better than that with the same power

But then someone could probably bring a better single graph and so the story goes

I agree with Cubes for the most part on the points... although the -5's are now making nearly 400rwkw now... so i'd say revise 360rwkw with 400rwkw

The twins are only about $500-$600 more expensive than a single Garrett (which is pretty interesting)

But the money is saved when you factor in manifold and oil/water line costs and so on.

Long term, single would be cheaper from a servicing point of view (should you need to get it off more than once)

Twins are a mega pain to take on/off... so doing it more than once would bring the single infront from a cost point of view

You can split any block if you really want to try it.

Big RPM launches on sticky rubber, and you'll soon have that familiar coolant drip on the ground when you park it.

If you dont launch it hard, constantly etc, blocks will be fine.

There are that many people making over 300rwkw now on a factory RB26 block that any problems would be common as dog poo.

The more knowledgeable builders will make some changes to the block to stop this from happening, but there are a lot of backyard style builds who are only upgrading pistsons and similar without modding the block itself... And they hold fine is treated with some respect

this motor isnt built, its standard from nissan...

i had a stock block with 430rwkw no problems, but it was prepped like u said. but once again i refer to the fact we are talking about a standard engine

[SimonR32]

need proof?? dude ive got a stock block...

made 300awkw no problems which more power than what urs made...

plus theres plenty more out there makin tons more

as for proof on twins.. its physics.. so unless u can break the laws of physics which u cant, then stfu

actually i made 430rwkw using a stock block, dont try a be a hero cause i have a bigger dick than you... my STOCK motor made 300rwkw

but without prep work a stock block will start struggling around 300-330rwkw

stfu is not a good argument, the fact is with a single you get twice the amount of force pushing on approx double the amount of mass, so in theroy there should not be a lot of difference at all. so the laws of physics actually state that they should be very similar

in practise they are similar, but twins have better response because of the small cast manifolds where singles have less lag and better top end power