Jump to content
SAU Community

Recommended Posts

Gday guys I was wondring if any1 has advanced the timing on an rb25de, does the variable valve timing have any effect? will it make much difference? cheers

i've done it on a few rb25de's and its a nice little improvement. For something that cost nothing but 5mins of your time its great :down:

Just loosen the 3 10mm bolts holding the cas untill you can turn it. and turn it ANTI-CLOCKWISE, you'll notice the idle will jump up a few rpm. You dont need to take the bolts all the way out. If the rpm drops you are going the wrong way, ie dropping timing. If the idle is sitting too high afterwards, just adjust the idle screw a few turns, but you might not even need to touch the idle.

Mine is probably 2mm from being "maxed" out, since theres only so far you can turn it. My brothers on the other hand is fully clocked across haha...

Take it for a spin afterwards and listen out if it pings, if you can hear it pinging drop it back a notch and try again. The best time to check for ping is during the day when its warmer and under full load (ie 1500rpm in 2nd then floor it). You should be running 98 ron fuel normally, but if your arent, you definately should once you've increased the timing, otherwise you'll knock the engine to death. If you dont know what ping is or what it sounds like, get someone that does to go for a drive with you.

Like i said its free hp and you should notice an increase in fuel economy aswell, win win.

The rb25's dont have variable valve timing, but they do have variable cam timing, but bumping the ignition timing wont effect anything to do with it.

:laugh:

Edited by R34GTFOUR
i've done it on a few rb25de's and its a nice little improvement. For something that cost nothing but 5mins of your time its great :)

Just loosen the 3 10mm bolts holding the cas untill you can turn it. and turn it ANTI-CLOCKWISE, you'll notice the idle will jump up a few rpm. You dont need to take the bolts all the way out. If the rpm drops you are going the wrong way, ie dropping timing. If the idle is sitting too high afterwards, just adjust the idle screw a few turns, but you might not even need to touch the idle.

Mine is probably 2mm from being "maxed" out, since theres only so far you can turn it. My brothers on the other hand is fully clocked across haha...

Take it for a spin afterwards and listen out if it pings, if you can hear it pinging drop it back a notch and try again. The best time to check for ping is during the day when its warmer and under full load (ie 1500rpm in 2nd then floor it). You should be running 98 ron fuel normally, but if your arent, you definately should once you've increased the timing, otherwise you'll knock the engine to death. If you dont know what ping is or what it sounds like, get someone that does to go for a drive with you.

Like i said its free hp and you should notice an increase in fuel economy aswell, win win.

The rb25's dont have variable valve timing, but they do have variable cam timing, but bumping the ignition timing wont effect anything to do with it.

:(

thanks a heap man, just what i needed. btw cas = camshaft sensor? and where do u adjust the idle does t has an adjustable needle on the throttle body or sumthing? cheers

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Haha I do that.. thats when it chirps..The bit point for me is almost non-existent. Otherwise I stall it. But yes, in terms of performance, the clutch is solid af.
    • Greg speaks wisdom. These dirty old Datsuns are only value when they are cheap. When they are not cheap, there is no value. Sounds contradictory, but it's true. We are now 20 years past the hey day of modifying cheap 90s JDM cars for small amounts of money. This is a different world. If you are rich and can afford not to care about what is effectively wasting money on an old Datto shitter, then I have no reason to argue against it. But if you are wanting to experience what we all experienced back in 2005 (and I bought my car last century!) then there is no way to do it.
    • Short answer: No. Medium answer: No, because you still need to conjure the things out of thin air to bolt them to a NA to make it a NA+T. Long Answer: No - The things you need to conjure - meaning a turbo, intercooling, manifolds, exhaust, intake/manifold/piping, clutch, injectors, fuel pump, AFM (?), ECU + Wiring (woo, N/A loom fun) have to come from somewhere. You could have many scavenged these things from an OEM car that someone had upgraded from and use some of these. This will be cost prohibitive now, especially so in the USA. You'd probably pay the same for newer, upgraded components that are better than old OEM stuff from 25-30 years ago. None of these big ticket items are re-usable for the N/A car. Why not buy new and upgrade while you're there? The only real consideration is turbo and fuel sizing and determining whether you want to stay within the bounds of the OEM engine or get into rebuild territory. These limits ARE lower with a N/A motor and especially N/A gearbox at the starting point. And if you're gonna upgrade those then you may as well consider having them built to begin with. Because everyone here knows you're never far from that next engine rebuild once you start making the power you want... The cars you see on the internet and SAU etc have been built over decades. If you're really clued in... you would sell your US car to somebody for what you paid for it. You would then scour AU JDM pages or SAU and buy a car like Dose's on this forum with your powerful American Dollar. This will save you so much money in the long term. Importing it could be tricky. Or it might not because USA. I have long said the only reason 90's Japanese stuff took off was because a) Japanese people had Japanese cars so that is what they used b) Australians could import these cars to Australia with very minimal changes and use them on the road here c) Neither country had well-priced access to US or EU Sports Cars. I don't believe the JDM scene would have taken off in Australia at all if we had EU priced EU BMW M offerings, or more especially the AUS V8 Scene would never have existed if we had the multitude of US cars like Camaros, Mustangs, Corvettes at the prices you folks do. After all - Do the math. I would say put a V8 in your R34 and that's the smart way forward. It is. I did it. I know this from my own experience. But at that point there's no reason to simply not buy a C5 or C6? It would be simpler and easier and cheaper and bette-
    • Reading all this... hurts lol. I have an ENR34 5MT and I paid an inflated USA price for the car alone, had to do tons of preventative maintenance past that, and so I'm over $30K USD into the car already and haven't even touched power.  I wanted to +t it. Not even trying to make GTR numbers, I'd be happy with 250hp.  Can I get away with paying much less to make that happen?
    • Damn you’ve done well, definitely snapping necks.
×
×
  • Create New...