BHDave

I got to see one on a dyno a couple of months back while i was waiting for a run, it pulled 120fwkw and absolutely screamed (nice sounding) at the top end. It had a few mods, pod, extractors and exhaust.

I'm running one behind an rb25 making 220rwkw. It's been in for over 6 months with no problems. Thats with a 1060kg pressure plate. Nice to drive, a little bitey/shuddery when engaged with low revs.

It'll be back pressure related. Drop the exhaust before the cat and take it for a spin.

The first thing you want to check is that the CAS, injectors, coils and ecu are getting power. You should be able to hear the eccs and ignition relay flicking in and out when you turn the key to ignition and back off. The ecu should also be lighting up the red LED on the botton edge. If you cant see the light or hear the relays then you need to re trace the power feeds.

You may be pushing further into the rich/retard section of the map by improving the exhaust flow and increasing the boost. Your initial run of 208 seems to me to be inflated (particularly as you still had only 10psi and stock front pipe). Your second run with the front pipe on seems to be on the money as far as power for your mods. As there is no air fuel ratio shown i cant say whether your safc needs retuning. $300 bucks for a tune only is a rort. Some one is having a lend of you as it should take all of half an hour to do a complete retune on an safc.

Thanks for that. I wasn't after a highly technical answer anyway, more of a general idea of what will effect the limit. I hadn't considered the oil pump or other anciliarys either.

You seem to be getting big turbo/small engine type response but a disco isn't a big turbo. Can you check the part number? Check it against the numbers listed on www.turbobygarrett.com .GT2860RS is the disco i think.

I think grim may be on to something. I would expect that a properly designed internal wastegate is capable of flowing enough for the turbo, particularly as it is an aftermarket model designed for 1+ bar. What type of dump pipe are you running? could it be preventing the wastegate opening properly. I've seen it before.

It seems pretty laggy for a 2530 equivalent. The discos rated around the mid 300 hp mark, my old highflow rated at 470-480 (stage 2 gcg) was coming on around the same point. I think the step down at the adapter could be causing a few problems, maybe. I would have thought the turbo would be making decent boost at 3500 or so. What is the response like? Is it coming on really slowly initially than shooting up to 1.1bar or is it building to say .6 quickly and then slowly rising to 1.1?

So there's more to it. Though the difference between rb25 and 26 stroke is pretty small and they have rods the same length right? Though the 26 ones are stronger.

Hi guys, Just something i've been wondering about the last couple of days: How and why has Nissan decided the redline/rev limit in the different capacity Rb engines? For a start, the 20 with the shortest stroke has a limiter around 7500, the 25 (s1 r33) has the limiter around 7k (mine was at 6850 or so with the stock computer) with the next longest stroke and the 26 is up around 8 with a longer stroke again. What i'm wondering is obviosly the stroke has little to do with it so is it the crank design (counter weighted vs not?), or is it the head design? the 20 and 25 share similar lifts, durations and hydraulic lifters so why the 500rpm difference, while the 26 has solid lifters and bigger cams (so more stable at higher rpm?). Or is it the stock turbo? How do people with rb30dets decide on a safe limit to use? And whats to stop me (other than increased engine wear) raising the limiter on my rb25 considering my power is still rising pretty rapidly at redline? Thanks for any replys, Dave

silver with red painted rockers.

I'd send the question to Nengun because i think it may actually be the size of the bellmouth on the turbo 3inch vs 4inch rather than the size of the actuator because typically the hks actuators are closer to 50mm diameter. The size of the actuator would have little effect, particularly if it's an adjustable type like a HKS one.

They'll fit without lipping the guards if you run skinny tyres 215/235 f/r though the clearance to the Hicas ball joint on the rear will be very close with the +38 offset.

Dont you mean the worst of both worlds? R32 with sr would be the best Ultimately the choice will be yours. The 32 is better built, the 180 is cheaper to modify. As far as which is better, you are going to have to take a few for a drive, look at the overall condition and price and make a decision based on that. Both are good cars, i've been in some pretty quick examples of both. Bang for buck my mates old sil80 shat on anything i've ever been in, owned or driven and it only ever had the usual bolt ons and a set of cams, stock ecu and injectors and a jap s15 turbo. Made about 190rwkw and was an absolute weapon. My R32 with 220rwkw feels slow in comparison and has cost me twice as much (thats with an rb25 too so no big torque hole at the bottom end).

It looks fine to me. 3rd gear run rather than 4th (probably to avoid the speed cut, not many mods, not much boost and the good old r33 ecu.

As most people have been saying it is most likely a channel on the ignitor. If it is a coil (not saying it isn't as i've had that problem aswell) you should be able to see the coil arcing to the head if you run the engine in the dark. I have had both fail though the coil related miss was intermittent and wouldn't start until the car had heated up after maybe 5 minutes of idling. It would also fire occasionally so wasn't completely dead. The dead channel on the ignitor is my pick.

Then you've got the same thing on the ignition side though dont you? As the q45afm is giving a lower voltage for a certain air flow wont it be looking up a point in the map with more ignition timing than is safe?

You need to make sure the eccs relays are wired in correctly as well as the ignition switch signal to the ecu. The ecu triggers the eccs relay to power up everything when it receives the ignition switch on signal. It also maintains power to the ecu for a second or so after the ignition is switched off which is when the pfc writes everything to memory.

For a start you can check error codes on the ECU. Check for speed sensor input (i cant remember the code off hand) No input will mean the ECU thinks the car is at adle all the time. It will usually cause the steering to be very light and then after 5 mins or so it will go heavy and the light will come on. Also check the hicas control unit under the rear parcel shelf. There are 2 plugs, make sure they are both plugged in properly. Having one of them unplugged will lead to heavy steering and the light staying on.

yes. The part numbers are different by one digit depending on the age of the coils you get but they are the same and work fine.

Yes it is. All items sold, thanks to everyone for your interest.

I found my stock actuator would drop back to 10-11psi at any boost above that. An aftermarket adjustable would be well worth a look for 2 reasons: 1) you can set a higher base boost on the actuator and so are garanteed of that whatever your ebc does, and 2) The higher the base you set, the easier it will be for the ebc to do it's job and as a result you will have a more stable system with less spiking and a flat line to redline.

Yes, it's a GCG rebuild with a new ball bearing cartridge.

Actuator sold. Turbo price dropped to $1,200 ono