Roy

They are the same A/R so not likely to make a big difference. 3" means more changes to inlet piping vs std vs 2.4". But more importantly there is reason to believe anti-surge covers take a bit away from response so 2.4" is easier to package and make look std. If you go 3" just go std 3", not anti-surge

Just scrolled through the RB20 dyno results thread. The Hypergear turbos all seem very laggy, but there are so many versions of the things perhaps they are older versions Hypergear OP6 Hiflow may be more suited to an RB25 Stock RB20 HyperGear ATR43SS1 (none PU version) turbo internally gated bolton to stock manifold. 3" Turbo Back Exhaust Nistune tuned Pump 98 Fuel FMIC 480cc Injectors Bosch 040 Fuel Pump 3inches hard intake pipe with Pod 227rwkw (green) @ 18psi It doesnt seem a bad option if you want a bit of headspace FJ1600s results 92' gts-t Stock Internals - SSS Automotive Wrecker Engine Bosch ev14 750cc injectors Z32 AFM Walbro pump Sard FPR Red jacket coils Bellmouth dump and 3' exhaust + decat GRedy Profec B II FMIC Hypergear RB20 Highflow Turbo PULP 98 224.8kw on 17psi Stock RB20 RB20 Turbo Hypergear Highflow 3" Turbo Back Exhaust Nistune tuned on V-Power 98 Fuel GTR Intercooler 555cc Nismo Injectors Walbro Fuel Pump Splitfire Coil Packs Greddy Profec b Spec II Stock Airbox and KN Panel Filter 201rwkw @ 20psi (High), dropping a bit to 19psi and 174.6rwkw @ 14psi(Low). Did 206 with the cat removed, but the engine started pinging as the timing got advanced, so had to leave it with the 201 tun

I would personally go for the 2.4" compressor cover, rather than the 3" anti-surge cover. But importantly they are the wheels and turbine housing to go for

From RB20 dyno results thread 1993 R32 GTST Stock RB20DET TD05-18G (EG 8cm) Nismo 555cc (with GTR Resistor Pack) Nistune 3" Turbo Back Walbro 255 FMIC Z32 AFM United 100 RON Stock engine, stock manifold, stock cams/gears.. With some cam gears dialled in you woudl expect to pick up a little bit in response. Not sure what T3 housing he has

They are just spreadsheet dumps of peoples dyno sheets over the years. God it was from about 2004-2005 So there are differences in dyno types, dyno operators adn importantly wheel sizes. The rolling diameter of a 16" wheel is a lot smaller than an 18" so if going by road speed you can think something is more responsive than it really is because of the smaller wheel size. So, the important take away IMO is arming yourself with a reasonable expectation and then speak to your tuner. Your tuner is paramount and get them to show you different graphs all from the same dyno so you can compare apples to apples. If you are in your states SAU club jump in cars and go for rides. And lastly, dont rule out the Hypergear turbos I guess. From what was posted his T3 offering for his SR20 turbo is a bit of an abomination with buts welded on here and there to make work, but if there are some good results out there for an RB20 then it should be on your consideration list. But the RB20 result he posted was not all that promising, though that may be that particular car and not the turbos fault

So cliff notes. TD05 and TD06 are referring to the turbine type and size. 16G, 18G or 30 , 25G are all referring to the size of the compressor. So, if you are going std internal gate bolt on turbo I personally would stay away from anything as big as a TD06. That is the same size turbine as I am running and can make 300-330rwkws. So waaaay over what you are after and in turn will be bigger and heavier for the exhaust gas to spin so...laggier than you need So the compressor side of things...if you go for as late a model 16G based turbo you will be in the window of the power and response you are after. IMO stay away from 20G or even 18G as the 18G is really the same size as the 20G , just a different trim. So again on 98 fuel it is a 270rwkws turbo. So, for me and what I understand your needs to be...I would be looking at getting Kando to price up the following turbo for you. T3 TD05H turbine housing http://www.ebay.com.au/itm/Kinugawa-Turbo-Turbine-Housing-Nissan-Skyline-RB20DET-RB25DET-8cm-TD05H-T3-/271807706353?pt=LH_DefaultDomain_15&hash=item3f490074f1 Cartridge http://www.ebay.com.au/itm/Kinugawa-Turbo-Cartridge-CHRA-TD05H-Small-16G-Oil-Cooled-49178-54700-46-60mm-/271531508287?pt=LH_DefaultDomain_15&hash=item3f388a023f And run a 2/4" Compressor cover. Effectively that is an old EVO turbo If you want to go to basically an 18G sized wheel, just the smallest trim then get the 16G6 (in Mitsubishi world they call it a Big 16G) http://www.ebay.com.au/itm/Billet-Turbo-Compressor-Wheel-Mitsubishi-EVO-3-TD05H-16G-48-30-68-01-mm-6-6-/291401525948?pt=LH_DefaultDomain_15&hash=item43d8e26abc And run that with the T3 Skyline housing from above. DO NOT take thei std T3 turbone housing as they are POS! ie this They are horrible on the exhaust side for flow

The tough thing is you are really all out there on a ledge. Can't look to late model production engines, race engines etc because your rev limit, power level etc are all very different. I was reading about the 1.6L turbo Toyota engines that are being developed for the WRC program as a platform are rated up to 600hp for various classes of racing. The problem is what impact do inlet restrictors etc have on head design. Anecdotally looking at pics of their head and also other turbo LMP engines they all seem to have squish pads. Ditto F1 V8 and V10 engines so it doesnt seem to be a high rpm NA thing either. So, i think the main thing is to go with the one mob for concept ensuring piston shape, injector type location etc are all factored in...

LOL, I love the thinking you put into your car. I have gone down the same road with trying to get some weight out of the std doors I am loving dimple dies at the mo

LOL, just trying to turn this into an RB25 > RB20 thread due to displacement Interesting discussion and the only person I know who had really spent time and folding stuff on a head was Doughboy with what was a very expensive head which sadly got sold as he went the route of the Ford V8 for his drag R33. But I am guessing you know Rams in Windsor and have spoken to them about the whole head/piston combination options?

Dont waste your time and money. A stroked RB26 will always be laggy and a waste of time. People use to stroke RB26s before alloy chevs were around or the XR6 motor came out so I .... would just put a Barra XR6 motor in it, so much more responsive. Or maybe just put an LS1 in it.

I discovered last night I hat Homo more than Vettel...and actually was rather happy for Vettel. Loved hearing Homo sook on the radio...Skysports jump on Rosberg everytime he talks on the radio

LOL, my car is a street car first, track car second and is a huge compromise on the track because of it. What makes good usable power on the street makes for good usable power on the track. Its not like a slow street car will make a good track car!!! A TD05-16G may work ok but frankly...lottery dip stuff.... IF you are going to go anything after your RB25 turbo its a GTX2860 or grab a used 2530.If you are going to spend the money dont do it with one arm tied behind your back. Like i said, dont tune the RB25 turbo setup and go straight to the better turbo and you have just saved yourself the difference between a cheap lottery dip turbo and a better turbz that will give you a good result. But i get the reason why the poster wants to run his RB25 turbo for a while. The 2530/2860 is a good bolt on option...but dont think its massively more responsive than a bigger turbo that is a proper full setup. All different dynos and tuners but here are a bunch of plots but reckon it paints the correct picture

The only reason why a metal headgasket may be a good idea is the RB20 is no spring chicken and a fresh headgasket would be good insurance. But if the engine comes back ok from a leak down test...why spend the money on IMO conservative insurance. This is a wrecker motor...abused for years and if you are only doing the occasional track day at way less power than me then I would be suggesting std headgasket, studs etc etc are all fine. But you have to go with what your shops tells you as they have to stand by their work. But personally....I wouldnt be wasting my money on all that fluff. Std engines well serviced and tuned are perfectly reliable...especially if you keep revs under 7,000rpm and boost under 18psi...lol which i dont Rather than studs yadda yadda a better oil pump would do more imo

.OH. Hope the pit stop was because you were on a promise from a grid girl!

lol...i am watching you live on Foxsports...wind the bloody boost up will yah! Commentator is saying GTR

So Nissans Mardenborough just about had the worst experience anyone could ever dream. Poor kid was due to race at le Mans with but after a big crash at the Ring yesterday at Flugplatz his car jumped the fence and killed a spectator

LOl, the problem with RB20s are just like the JMS car they put the wrong turbo on things and when the result is a compromise they blame the RB20. LOL putting a gate on the std manifold, using a 20G off a rotary with a waay too big A/R turbine housing will certainly make good power and turn tyres...but it was alwaas going to be a compromise. Must be RB20s But that drift Onevia was just a bit of fun....and they knew it was less than optimal There is nothing special about my setup at all. Those that have done similar / copied have all got the same or better! Just dont put a turbo built for another engine on an RB20 or run a MINES ECU etc etc.

Why are you looking at a stroker? IMO don't waste your time with headgasket, cams, ARP studs etc. Just put a decent turbo on it and enjoy it.

Out of interest, what mods does your current car have to the RB20?

Feed the things E85 E85, std inlet manifold, a better turbo ...something like a FP HTA 71 or HTA 68 turbo and it would be pretty easy to blow my results away....lol the sh1t you learn getting it wrong

How good is Mad Max...Christ!

Ok,Full Trust TD06-20G setup with std inlet plenum and cams optimised with cam gears all tuned up. I then tried Apexi 260/8.8mm cams and went backwards. Tried different cam gear settings and engine lost response and didnt made the same peak power , never actually catching the std cams. Engine sounded tough but was seemingly over cammed. So std cams went back in. After everyone saying how good 6boost manifolds are I sold my Trust manifold and gate and went Turbosmart gate and 6boost So that was a disaster...spend money to lose power. At this point i tried 256/8.5m Poncams and did stuff all to help response but did make a bit more power. At this point I was desperate for response so in went std cams again which made the thing a little plunchier So reading about Plazmaman plenums...I thought I would give one of them a try....hopefully grab some improved response LOL...nope. So going to 6boost and Plazman was a step back ON MY SETUP. Perhaps because my tune and setup was pretty well optimised and proven with a few years of track work before I started trying different things. For me, if I had stuck with std inlet plenum and Trust manifold and gate my car would have been a good bit quicker than with the bling bolted on. I lost a headgasket when a hose under the inlet went in traffic so I put in an NA R32 RB25DE that had rebuilt internals. All the bits from my RB20 were swapped over and after a bit of trialling my TD06-20G with an 8cm and 12cm housing and with / without the Poncams put back in...the Poncams in my RB25DE certainly helped the power curve , though didnt really change when it came on Ev Even then we found a problem with the Turbosmart gate so its possible it was leaking on the std cam pull making the setup a bit lazier. With the gate fixed it held boost and made way better top end, around what the RB20 was making. The above plot wasnt full tunes. I just wanted to see the general behavior of the setup of different turbo, housings, cams etc to decide which direction i wanted to take. Ended up going T67 and frankly 12 months later I am going back to my custom billet turbo SO, after 16 years of playing with my car, 15 of it with an internally std RB20.....from a value perspective the std inlet and cams give the IMO the BEST bang for buck If you want to run Poncams then there are those that have had good results...but inc tuning, labour and cams its what...at least a $1500 mod and I guess thats up to the individual to say whether that investment is worth the improvement (keeping in mind that some people go backwards)

Tah...my trials showed std cams with cam gears gave me better power everywhere vs cams, inc torque. Playing with the tune/timing etc with cams just got me back to the same place. But i run a very diffrrent turbo setup and the cams were with both a plazmaman plenum and before the plenum so engines would be working very differently. My mate swore the drop in cams helped his HKS 2530 setup as well so....many ways to skin a cat

By "Renaults numbers" I am assumning the data they have to compare between the STR and RBR chassis. So I preseume they make the pretty safe leap that both are light years from Mercedes. But, James Key is one clever fella...he almost got Force India a victory at Spa and FI were a pretty competitive team...and we saw what his car in the hands of Perez did at Sauber before joining STR. So STR could easily be a quality car, so being marginal behind RBR need not be a huge indictment of RBR. Sepang will be a good test...Lotus to score big points this weekend!

So what cam gears did you have before the Tomei cams went in?