Steve

buggered if I know:D (note to self - check)

I dont know what the top end will be like if I move the cam forward, might have to ask that question of Richard, as I didnt drive it before and after he started adjusting, and it hasnt been on a dyno yet.

Oh, I know what I want for christmas now, a baka gaijin shirt. anyone know where I can get one?

I think this Japan forum should be renamed Rezz's Forum - as he has posted up nearly all the threads:D I do have a question though, on one of the other threads it says baka = stupid, I was under the impression that this actually means crazy or does it mean both. Also, could you enlighten me to about gaijin - I have been told by a ex pat Jap that it is a derogatory term, to quote 'same as calling a negro a African American' is this true also?

yeah, probably good for top end (which it appears to be) - and is what traditional tuned length exhaust manifolds do. The jap ones for the street tend to go 3/2/1 or blend the pipes into eachother on the way, and have a pipe before the turbine flange - Richard suspects this acts to accellerate the gasses before they get to the turbine housing. I always looked at these and though 'it has to be better with minimal interference before the turbine', as it would reduce back pressure there fore promote scavenging. Most of the research I have done pointed in this direction too unfortuneately. At least I know now, tuned length great for drag or use a small housing if you want it on the street. I cant wait now to get the smaller housing on and see how much the top end suffers.

At least you dont have to take the top of the plenum off, like when removing injectors, just throttle body and cross over pipe - or am I assuming incorrectly that there is enough room with the top feed injectors in place?

Thanks B-man, I havent taken the photos yet:) I was going to post up some pics of the newly done plenum, and a dyno sheet, although I wont be getting a dyno done until I sort my exhaust manifold/turbine housing debarcle:) I will be in touch when I get the photos sorted if that is ok? Cheers again Steve

Glad you enjoyed it, I will be definately doing the housing first, just a shame that I already sold my 0.61 (hindsight) then take a look at top end and decide whether or not to change the manifold again. the off boost is very, very good - much better than with stock cams and no head gasket, so although I think you are right, it does effect off boost and spool, it would appear that the cams (and adj cam gear) more than compensate. Can never tell exactly when you do more than one mod at once, but as the head was coming off, I thought it would save a few dollars.

Radius rod adjusts castor, no?

Hmm, I have found that braking too hard into a corner - or rather too late, will increase the likely hood of oversteer. Just like if you back off too quickly during oversteer. Too much weight transfer to the front wheels, or just enough if you are into that sort of thing:D

I have a HKS 3037 on a custom manifold. The manifold is tuned length highmount. Originally the turbine housing as 0.61 AR, which brought 1 bar of boost on at around 3000rpm, and hit very hard - too hard, but torque was flat to redline and gave a reasonable 256rwkw at 1 bar with a very 'quick fix' tune. At this stage, I was going to get cams fitted, with a 1.6mm head gasket to drop the CR and allow a safety margin for higher boost. I decided at the same time to get the 0.87AR turbine housing fitted, as I was concerned that the small 0.61 housing was going to choke the top end. Initially on the road the car was very crisp off boost, showing much better characteristics than before the cams and head gasket went in. All was good. I decided to give it a 'gentle' thrash. Lag, lag, and more lag - the car was a dog. I couldnt think what could be the problem, unless something mechanically was not right. The new setup didnt make good boost (plant you in the seat) until nearly 6000rpm! Nothing at all happened until over 4500rpm. I almost cried. I sent the car off to be tuned. Fortuneately for me I managed to secure the services of an excellent tuner. He tuned the car for 2 days - on the road. Idle is excellent, power is very smooth and very good off boost - alot better than before. The lag however has only been moved 800rpm lower (thanks to -6deg on the exhaust cam, and very good tuning). the problem as Richard sees it (he is doing the tuning, and also was responsible for JMSs Red R33 - which still has the original motor in it, just spun a bearing with 2 bar boost on a cold engine, long story) is that I have a manifold with long runners, that collects into one outlet. This is very different to the way the Japanese have made their manifolds for street use turbos. They (japanese) use very short runners, which arent tuned length, and according to Richard are designed to get very high exhaust gas velocity before it hits the turbo, which a tuned length 6 into 1 will not do as well. The tuned length manifold is very well made, just doesnt match the turbine and application I have. Richard is convinced the problem is the manfold isnt creating enough exhaust gas velocity to use the 0.87 AR housing, which isnt too big for the engine, but is too big for a tuned length manifold and this turbo. He has seen the japanese manifolds, and they work very well at getting gasses into the turbine housing very quickly, use some crazy rocket science which comes from extensive R&D - therefore allowing the use of bigger turbine housing. Now I have a bit of a quandry - do I buy a Jap made (designed for this turbo) manifold, redo the dump, wastegate, afm and intercooler to turbo pipework, or go back to a small housing? I am not sure the smaller housing will be ideal for top end, but it does wonders for bringing in boost early and spooling the turbo quickly. But I dont know which option would be optimal for response and top end. I want it all if I can have it:D I am a bit concerned about back pressure, as I am running inlet an exhaust cams - too much back pressure will rob power very quickly, especially as I have a bit more overlap now than stock cams. (oh and the VVT still helps alot with off boost response, even with the cams fitted - much nicer to drive with it connected) I dont want to go changing things again only to have to redo them again, its not a cheap exercise (r&d is expensive:() Either way, I have learned a very valuable lesson, that I thought I would give anyone who is at the point where they are considering turbo and manifold upgrades something to consider, maybe in a bit more depth than I did (and I did spend alot of time reading and researching, just didnt ask the right people I suppose:)) The runner size and design of the manifold obviously has a massive effect on what housing to use, and also how boost is being made - dont underestimate the proper design of a manifold. Something to think about before deciding which manifold and housing to use. And, dont underestimate the amount of science that goes into the design of a Jap manifold - they make them that way for a reason. Rule of thumb, longer runners, smaller turbine housing, shorter runners, bigger housing. May have a cermamic coated tuned length RB20/25 manifold on the market in the new year:D Either that or a 0.87 HKS GT30 turbine housing:p

Whatsisname and Bman, very nice guys. Matt, I cant believe you were actually thinking of selling. Oh, and ist it a good idea to put the injector loom on before the top of the plenum? Nice work.

Thanks guys, now I just need to find me some webspace:)

Ahh hippy, you are a constant source of amusement for me:D

Sorry to hear, I hope it works out ok.

Well, looking at what you have done mod wise, probably not too hard to come up with a solution. Just be aware that there are many different solutions, and its not as cut and dried as you may think. there are volumes on here already about turbo selection, what to expect etc, also the limitations of different mods. Basically, you are only running a GTR pump - which will limit you to around 250rwkw. That is also pleny to destroy an RB20 gearbox. Do a search and look at something along the lines of HKS 2530, or even a high flow RB25 unit. Either of these will deliver 230rwkw, and you will probably find your gearbox is at its limits. Alot of your mods are a bit over the top for that sort of power too. Seriously, have a look around the forum, use the search tool, there is heaps of info on RB20s, turbos, and other mods as well as when you need to look at doing them.

OK, lower temp in the pistons, but what about the thermal characteristics of the surface of the ceramic coating? would it heat up more than a standard piston? same with valves? If the coating prevents the transfer of heat into the pistons/head, wouldnt it also therefore prevent some cooling? Increased heat after the exhaust valve shuts could be nasty, even if it does mean greater exhaust gas velocity you will have a higher charge temp on induction - yes? I dont know the answers, but I think the questions should be asked - it is very rarely that a mod gives without taking somewhere:) And BOOSTD, sorry for the postwhoring, but you have finished with your question yes?

And what is the car being used for? what sort of power are you after? Street, circuit, drag?

Vacuum is a bit different to boost - the hoses will respond differently. I am just attacking from the point that if it all worked ok before, what could be different or broken since? Have you cable tied all the hoses you changed?

Engine? Manifold? The wolf 3dv4 for skyline (plug n' play) can be used with MAF or MAP

AFAIK it wont make alot of difference tuning the car before or after. The cam gear optimises the tune/setup. You did say you wanted thoughts:)

Yes Sydneykid, I was waiting for it:) I suppose I am a bit detonation paranoid, if I can get a large margin for error, without costing me too much power, I will gladly take it. Jimx, I didnt o-ring, as I believe the HKS gasket is more than adequate without o-ringing. If I was dropping CR by different means I would look at getting o-ringed with stock gasket, but I didnt want to spend a fortune on head work or rebuild the engine, ie, took the quick fix. But if it works, why not?

Might be pushing getting 300rwkw from 2835

denial works for me:D

Paying you out! OMG, here I am just trying to help you get in touch with your true inner self, get you out of the whole denial thing and this is all the thanks I get! women:p