Cossiemainful

iTrader: (1)

Hi folks, as an ALS isn't my cup of tea (maybe cauz of the shortened lifespan for the engine and turbo?), what's the best combo for this rebuild?

I want a small and a big turbo to kill the lag. It seems that aren't many Twin Turbo Cossies around.

Any suggestions?

joffy

iTrader: (1)

think turbo systems did one a while back, might be worth speaking to tony

dojj

iTrader: (3)

turbo techics did a kit, but it was Ł6k

XRT_si

iTrader: (2)

For good reason! What kind of power are you looking for? As modern day roller bearing turbos are superb on the road.

carcollector

would love to see that happen.....ever thought about supercharging and a turbo with a K Valve like VW has done ?

dojj

iTrader: (3)

tt called it their k gate, i've got a write up somewhere one of the mags did i'll post up in a bit

XRT_si

iTrader: (2)

Good idea! On a Zetec being built:

carcollector

now we are talking !! this could easily turn into the thread of the yr

if we look back a bit more in history a Lancia S4 springs to mind, also on a dual kinda setup...

YOREVOL

ive seen this on a yb but it was a long time ago. turbo technics,turbosystems or graham goode cant remember who though.

Mike Rainbird

iTrader: (3)

Already been done, but as a supercharger relies on engine speed to work efficiently, low down power isn't particularly amazing in the 1000 to 3500rpm range you want it to work. The trick is finding one that is good enough to give 15psi from 1000rpm to 3500rpm, which isn't available off the shelf, as they're nearly all designed to operate over a much wider range.



Personally, I think compound charging would work better, using an ST turbo and a T4 (providing they were compatible) , arranged like this:
https://www.atsdiesel.com/ats2/templ...029932164&c=36

dojj

iTrader: (3)

https://passionford.com/forum/genera...ie-engine.html

v man

i think a t4 feeding a t66 would be best

Chip

iTrader: (3)

Would just be a load of complexity to still be laggy.

Fit a GTX35 instead

Cossiemainful

iTrader: (1)

not sure about the power maybe 900+ BHP. It's for a road car.
A minimum of lag is my purpose.

Mike Rainbird

iTrader: (3)

The blocks become unreliable above 600lbft, so you need to take this into account. The torque causes the cranks to flex which is transmitted into the block and they crack around the back where the bellhousing bolts.

Cossiemainful

iTrader: (1)

I see! Do I understand that you are talking about the 200 motorsport blocks?
Apart from that it's for road use, so I won't kick it permanently.
I think the way of driving matters too.

AustenW

Norris Designs has built an Evo with a supercharger and turbo charger to good effect

http://forums.evolutionm.net/evo-eng...arged-kit.html

http://www.lancerregister.com/showthread.php?t=295077

Mike Rainbird

iTrader: (3)

That is the 200 motorsport blocks with Nikasil steel liners, Arrow stroker cranks, Autoverdi rods and big turbos. The 2.0 litre engines seem better (much less torque), but you lose a lot of low down response.

900bhp seems a bit pointless for a road car, especially a Cossie with it's poor tyre foot-print LOL.

Even Rod's is only 830-ish bhp and that is crazy fast. Adding low down power combined with a 900bhp peak will in all likely-hood be too much for the block to cope with (although 2wd is likely to help, as excess power can be spun away through the tyres).

Chip

iTrader: (3)

600bhp and a single well specced turbo would certainly seem like a less painful option, you're likely to get a LOT of failures on the way to your 900bhp target, and its expensive to keep building these engines.

Depends on your budget i guess, if money is not a problem it would be good fun to try!

Shonky

900hp is more than a rebuild lol, it'll take a lot of development to get that, if it's 900hp you want in your cosworth then a v8 twin turbo would be easier, cheaper, nicer to drive and probably more fun!

Porkie

iTrader: (1)

so its for a road car? therefore no competition rules and regulations I guess?

and you want no lag and big reliable power?

EASY! stop dicking about with a pony 2litre 4 cylinder engine!!!

start with a Big V8 or a 2JZ straight 6 and tune those. massive power, less lag, simpler and more relaible.

hogdog

The golden rule of compound charging is that big feeds small so it would be a T66 feeding a T4.

Personally I'd just fit the new GTX3582r and be done with it, up to 750bhp and much less lag than older type turbos.

Chip

iTrader: (3)

Agreed, you need to be obsessed to a pretty serious extent with an engine to want 450bhp per litre from it.

Shonky

You need one of these

boy-racer-1

id be speaking to the person who made this engine if your going to make a twin turbo 4 cylinder engine, the one in the video is the lima 2.3 engine, very similar to the pinto engine with a volvo turbo head and looks like his is running good, dont know about performance though

http://www.youtube.com/watch?v=jMsMHvGwb9w

Rod-Tarry

Been there done that my Block split into 5 pieces in early 2006 running 900bhp. Have spent a fair chunk of money & over 5 years trying to solve it. We will know next year if running 900bhp is a goer .
How long do you expect it to last- can answer that as well 800bhp on pump after 6kmiles = worn end shells from the thrust loading. Im now going to dry sump. 35K may get you there but not without hours & hours of development & several failures ( Ive had 2 on the Dyno).

Think the master Julian has just cracked 900bhp & the engine survived if he finds it hard we all will believe me . 50K + for an engine like that.
Dont believe all you hear from make believe land even if its close to you .

Unless you wish to set records (thats why I persevered) dont even bother to start chasing 800bhp+ in a road car. Mine is mega fast but as practical as Mike R's haircut . It will be detuned to 750bhp cos chasing that last 100bhp is all compromise.

lee2cossies

iTrader: (2)

Would be nice too see it done would be different. Didn't Ava build a twin turbo set up? Sure I seen pictures on here?
As for the block problem sure I read somewhere that scs were working with cosworth to develop a cgi yb block to cope with huge torque?

Cossiemainful

iTrader: (1)

Nice idea, no doubt, but the originality is gone then, a 3dr needs a cossie engine. I know there's hundreds of other suitable engines for my plan but sometimes only the challenge counts and not the comfiest way.

scoooby slayer

iTrader: (4)

absolutely spot on that porkie, the other id add is a rips rb30

NEIL A

iTrader: (6)

This is the compound charged one AVA did , Im sure it had something like a T88 feading a T38.

Chip

iTrader: (3)

The fact you started a thread asking "which combo" as if its a common thing and people would know the answer to it, suggests that perhaps you dont realise how difficult building a 900bhp compound charged YB is.

What is your budget for this project?

Karl 3dr

iTrader: (9)

Excuse my ignorance because I know nothing about it, but why does the big turbo feed the small?

Karl

Chip

iTrader: (3)

Because the small turbo cant flow enough air to feed the big.

The small turbo will effectively breathe through the big turbo till the big one comes on boost, as being a big turbo its not a restriction, then once the big one spools up it will just push the air through the smaller one and the smaller one wont really need to do anything with it.

Its a bit like an intake restrictor on a rally car, they put it before the turbo as thats where it restricts, if it was after the turbo the turbo could use boost to force past it.
Same thing the small turbo, it would restrict the big turbo if it was before it, but if its after it then it wont.

Karl 3dr

iTrader: (9)

Oh ok cool, thanks chip, is there not a chance of damaging the smaller turbo through it spinning too fast due to the large turbo forcing such a large amount of air through it?

Chip

iTrader: (3)

There is a very real risk of that yes.

Karl 3dr

iTrader: (9)

Fuck that then l, i think I'd rather one big turbo and suffer the lag lol

Mike Rainbird

iTrader: (3)

That's why the two turbos have to be perfectly matched .

Chip

iTrader: (3)

If I was doing it, i would so it with a small supercharger and then use a bypass gate. (like the VW setup)
That way none of the components are strained mechanically.

But controlling it isnt trivial im sure, and making the map match all circumstances.

Fiesta_Jed

There is no point going twin turbo unless its compound charged (big turbo blows into small turbo).

Twin charging is cool but the turbo must blow into the supercharger.

Please for the love of god do NOT use a centrifugal superchrger they are

Dont bother with electronic clutches and bypass valves as they are also and just complicate things.

All it needs to do is:

Turbo > intercooler > supercharger > intercooler > inlet.

Mike Rainbird

iTrader: (3)

The problem with that is that the superchargers that would provide enough grunt low down would be overspeeding at high rpm, this is why you need to disconnect them with a clutch above 5500rpm . If it is efficient enough at high rpm, that means it won't work hard enough to be worthwhile at low rpm .