Cjmartz2k

Yeah, the exhaust side of my hybrid dodge cummins/yellow bus turbo is choking the shit out of my motor. I need a bigger exh side. I already have the turbine housing, I just need a HX40 wheel. My pressure ratio's in the exh manifold must be through the roof.

Well than, put it this way. The stock intake manifold is not very inefficient up to 500hp. I switched mine, along with cams and more boost, and I'm only making about 30-40hp more.

Dang, you beat me to it. It's only like 10 or 15 threads down. Search button still works last time I checked.

Yes, but you need a front facing intake plenum like a greddy or adapted RB26 intake.

O jeez, I just realized we were talking about dual RB26 meters, not a single RB20/25. Duh

O, my mistake. 300rwkw is around 450hp at the motor, right?

He was talking about 300hp, not 300kw for a stocker, although I think it's something closer to 340hp or so at the motor. I think Paul's numbers are a bit off also. I only pulled 4800mv through it at 400rwhp, and I'm ballpark 500rwhp now and pulling 4995mv through it on cold nights. I know it's a 5v sensor, but I've seen people go over that (to like 5100mv) making 530rwhp. I have sucked water into my intake after a carwash before and it pegged it at 5150mv. Nismoid, what kind of voltage are you pulling at that power level?

It's power levels that lean out a fuel pump, so high RPM on a 400hp car ain't going to lean out a Walbro. My friend with the TO4z, however, did see around a 5-10psi drop with 600hp. Still nothing that's going to turd a motor as long as the injectors can keep the motor fat and happy, but on the edge no less. I have had no problem for over 2 years with 430hp up to around 550hp (at the motor) running up to 1.8 bar. I have never seen anybody on island here have a Walbro go bad, but I'm sure it has happened. Pretty much everybody here uses them, however. If I ever get my hands on another Holset HX40 turbine wheel/housing, I'll probably throw either another walbro in there or get a Bosch 040.

Sometimes people repeat so much of what they hear on the internet as gospel with out any first hand experience it's rediculous. I'm not saying Walbro's are the best, but I personaly know of 5 cars running a single Walbro over 500hp (at the motor) that have been doing it for over a year or two or three. One of those guys was running a TO4z and making around 600hp at the motor with a single Walbro, and he used to see a bit of pressure drop towards redline, but the car ran like that for a year. He's running a dual Walbro set up now. Would I run a Bosch 044 over a Walbro at that level? Probably. Will a single Walbro be fine up to 550hp at the motor? I'm betting my motor on it, and have been doing so for 2 years now.

So there are some HKS cams that will work with NVCS, or they are just designed to work in the RB25 motor? I was under the impression that Tomie Poncams are the only ones suited for NVCS.

http://forums.nicoclub.com/zerothread/192792

Holset HX35 or HX40 (or hybrid of the two).

You have to have datalogit and the software. You can't get to it in the hand controller.

I 100% agree. Seems some on here think they will magicaly explode after 400hp, but i've been will above that figure for almost two years now, and have several friends that are the same, but beat there cars WAY more than me.

Okinawa? Poncams for that or 256 HKS cams.

where are you located?

I'm in Okinawa, Japan, so it's pretty warm here. It's a sub-tropical island. It gets into the 50's (sometimes the occasional 40 something) in the winter and will tickle 100F in the summer, but it's humid as a mutha.

Dude, don't post two seperate threads in the same forum about them same thing with different titles. You look like a moron, and make us americans look bad in front of all the Auzzie's (sp?)

+1 for poor tuning, and 450hp isn't some magical number that can't be breached. I've been doing well over 500hp at the motor for over a year now.

Wrong forum. Belongs in forced induction.

I'm pretty surprised you said there is more clearance. Mine is tight as a frogs butt. Wait, you are putting this in a R33, huh? I've got a RB25 in my R32, so you must have a ton more room.

Sounds like a headgasket to me. Maybe a coolant line in the turbo(s), but I don't see how it would mix THEN make it through the motor. How does the oil on the dipstick look? Any oily film in the coolant (actually in the radiator, not the overflow)?

You can keep the RB26 aac valve, but you have to change to the RB26 oil cooler set up. Also, the RB26 plenum will not clear the VVT solenoid on the side of the motor. It hits a coolant passage, so you either have to do non-vvt cams, or do some grinding/aluminium welding. Throttle response is pretty cool though

x2!!! I'm going to have to create a word document and save it so I don't have to type this explination over and over and over and over. FOR N/A...... "Backpressure" is always bad. You want appropriate sized pipes for your power lever and desired rpm range. Smaller pipes equal higher exhaust gas velocity (EGV), but more "backpressure". If the pipes are too small, it will choke out the motor on the top end, but pull better low end until the smaller pipes become a restriction. Higher EGV helps pull the air behind (along with exhaust gas pulses) out of the motor thus helping said engine make more power. If you have a huge pipe on a honda, the air is almost stagnant in the exhuast and it kinda "bumps into itself" on the way out. If you have huge pipe (slow EGV) and put a big kink in it to create "backpressure" (restriction), you will have the worst of both worlds (like most honda guys, especially when they also realize they drive a honda ). BOTTOM N/A LINE-----SMOOTH, STRAIGHT, APPROPRIATE SIZED PIPE IS BEST!! FOR TURBO..... EGV and exhuast gas pulses don't matter (after the turbo) because the exhaust already has one big arse restriction messing with the exhaust gas pulses and EGV......YOUR TURBO!! For turbo cars, the bigger/straighter the better, for any power level. Now taste and common sense, that's a whole different story

Where in Japan do you live? O, and autos are for pussies.