Grant

Good little bit here too robbed off wiki Twin-scroll or divided turbochargers have two exhaust gas inlets and two nozzles, a smaller sharper angled one for quick response and a larger less angled one for peak performance. With high-performance camshaft timing, exhaust valves in different cylinders can open at the same time, overlapping at the end of the power stroke in one cylinder and the end of exhaust stroke in another. In twin-scroll designs, the exhaust manifold physically separates the channels for cylinders that can interfere with each other, so that the pulsating exhaust gasses flow through separate spirals (scrolls). With common firing order 1-3-4-2, two scrolls of unequal length pair cylinders 1-4 and 3-2. This lets the engine efficiently use exhaust scavenging techniques, which decreases exhaust gas temperatures and NOx emissions, improves turbine efficiency, and reduces turbo lag evident at low engine speeds.[34]

Figure 5. Cast manifold with a divided turbine inlet design feature Figure 6. Welded tubular manifold with a divided turbine inlet design feature A design feature that can be common to both manifold types is a "DIVIDED MANIFOLD" , typically employed with " DIVIDED " or "twin-scroll" turbine housings. Divided exhaust manifolds can be incorporated into either a cast or welded tubular manifolds (see Figure 5. and Figure 6.). The concept is to DIVIDE or separate the cylinders whose cycles interfere with one another to best utilize the engine's exhaust pulse energy. For example, on a four-cylinder engine with firing order 1-3-4-2, cylinder #1 is ending its expansion stroke and opening its exhaust valve while cylinder #2 still has its exhaust valve open (cylinder #2 is in its overlap period). In an undivided exhaust manifold, this pressure pulse from cylinder #1's exhaust blowdown event is much more likely to contaminate cylinder #2 with high pressure exhaust gas. Not only does this hurt cylinder #2's ability to breathe properly, but this pulse energy would have been better utilized in the turbine. The proper grouping for this engine is to keep complementary cylinders grouped together-- #1 and #4 are complementary; as are cylinders #2 and #3. Because of the better utilization of the exhaust pulse energy, the turbine's performance is improved and boost increases more quickly. Heres a little about it .. Basically its all about utilising all of the exhaust energy of an engine rather than having "waste" like in a normal set up ... The gases from 1&4 hit the bottom of the turbine in a contineous cycle and the same for 2&3 .. More efficient in short .. & better spool times .. Let me konw if you want some more night time reading/watching as have a few links

That sounds like a plan Will a twin scroll turb work with a normal mani?? If so what are the draw backs?

Yeah that's understandable mate. They are supposed to be good turbos. Quick spool and obv able to keep going at high revs as the Mitsi goes up to a similar level as ours. Did you have a twin scroll mani as well then?? That's a bargain for the box!! Fingers crossed for you mate. How many times have you changed the box now? 4?

Ha is that how much this one has cost!?! Lol. What turbo have you got lying around that you were going to use then?

Oh and yeah your right with the td05 definitely. My only draw back is that it's a lot of money to spank in one transaction.

When you say about the turbo still making max pressure Jake, I thought the whole point in the WG was so that it didn't? Or have I mis understood?? X2 your eg would be a complete animal boosted.

That's the sort of build I'm looking into mate Thing is, I'd think your like me in as much it's not going to be driven hard all the time. Not dragged or tracked regularly. Just the added "poke" for the open road

Edited by Krzys - Going to post details separately Is what I've just seen on Nicks FB. Assume it's his wife that's posted.

Well you should find him again !! lol There are an awful lot of boosted c4's on CL .. Can nick some theories etc from them .. Its all about research and then knowing what it is you want i think .. If for example, what i think by what you've said you want, i wouldnt really see the need to spend 3k for a setup only to run 7-8 psi that capable of much much more .. Little over kill isnt it?? If your just wanting to incrase by 20% then a budget build might well be the answer ..

Thats a shame mate .. Perhaps you could strip them down (or partially) and grease the sliders enough to get it through ?

Me too ! Loves a boost convo The thing that drags me back down though is the route to take .. Balls out and get the best, brand new Garrett GT2860RS with Brand new SS Racetech Mani .. New injectors, Stand alone Hondata s300 ..... Thats the best part of 2k right there ... Or do it on a budget ???? ???? ???? ???? Second hand turbo, probably something off a 200sx .. Cast mani, P30 or the like chipped .. Then having it mapped .. Could be done for less than a grand .... Grrrr ....

Thats the conclusion i've come to mate !

Ha although the asthetics are obviously a big part of it .. It does have bearing on performance .. But by no means are you going to get an extra amount of power by running an external WG at the same PSI as an internal WG .. Its all about control From my research, internal WG at higher power can "boost creep" .. And theres another term too but cant remember off the top of my head .. Internal - Basically, you can run too much boost and the spring isnt powerful enough to open .. Or it can open too soon and let boost off before you want it to .. This can also happen on an external i suppose theoretically, but ive not read that too much .. Everywhere ive read and anyone ive spoken to have all said "must go external" blah blah blah ... But my point is this, all the evos, all the scoobs, infact almost every turbo car from the factory run an internal. So why on earth, when we're looking at a relatively low psi of 7-8 (i have a freind with a built S3 running 26psi) would we justify an external ??? If you look at a brand new Garrett GT28, they are all internal too .. Until you get to the big ones .. Food for thought anyway ..

Well im sure we'll find out at some point I know that ARC do a black one already .. Which is alloy so must be painted! But yeah i get the idea with leaving it on display ! Yeah exactly .. For me and the research ive done, the Turb, Mani, Injectors & external wastegate (if your running one) are the things that really need to be good quality and branded ..

So far as i understand it, you can get away with painting it cant you? Well, the bigger the better is it not?? lol .. And IC is and IC i thought, dont see why Toyo can charge that much for one !!

Just having a quick gand of flea of the bay ... Whats the justification in this then ??? http://www.ebay.co.uk/itm/UNIVERSAL-FMIC-ALLOY-TURBO-INTERCOOLER-CIVIC-DEL-SOL-IC5003B-2-5-/190640775443?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c63136113#ht_868wt_776 compared to this ?? http://www.ebay.co.uk/itm/FMIC-FFRONT-MOUNT-TURBO-INTERCOOLER-HONDA-CIVIC-INTEGRA-IC5019-/200714336592?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2ebb81b950#ht_1053wt_776

Ah ok !! Exactly .. I mean slapping a boost setup on isnt going to please the purists anyway .. But id like to keep as close to OEM look as poss .. Esp on the outside! The FMIC is going to be a challenge to keep hidden!

Oh and for furture ref, dont leave your wheels under the ramp

Fustrating mate .. I feel your pain .. The brakes on these really are the achillies heel of M's .. You'll get there in the end though mate im sure !!

I thought the JDM was the C1? Or was that the yank? Like i said, not sure how much of an advantage a Teg bottom end would be, unless your looking at the head too .. For me, I want to keep with the c4 no matter what i do .. Just for keeping with the original lump

£50 for the sump ?!?! Holy mother .. Thats steep, all it is is a thread welded into the side!! Will make me own .. I mean, it would be easy to make your own You know, i always thought that when ppl said i have a b18c they just couldnt see the number after the c .. But that block genuinly doesnt look like it has one ! What were they from them and what are the specs?! C6 .... Oooohhhh good if your going to build one and get a c6 head .. Would use a c6 bottom end for turbo though .. Comp is alot higher isnt it !!

Exactly .. Not that thats my plan ... Or that i already have a spare

Or get yourself a spare lump (Bottom end) Then you can seperate it in stages .. Get the kit on and running on standard and then slowly gather the bits to rebuild the spare bottom end ..

Can't really say that it's a must, but certainly feel the difference top end with mine. Will be transferring it to the deck soon so will let you know as I'm used to driving with the standard one on!! Silverstone sounds like it'll be awesome mate!! Will you have to ego done before going too??