Jump to content
SAU Community

Recommended Posts

Car is a 89 S13 engine is a Series 1 RB25DET.

For some odd reason my car runs like crap on stock timing. There's just no power up top and it feels really rough. It makes lots of noise but doesn't really go anywhere. But when I set timing closer to 20* BTDC, it feels much better. It has more power and it comes on a lot smoother up top and down low. I know for a 5spd RB25 stock timing is 15* and for an auto stock timing is 20*. But my engine is a 5spd manual. I'm really stumped with this and I don't want to ruin my motor by running incorrect timing. Has anyone had an issue like his before? Any help is appreciated.

Car is a 89 S13 engine is a Series 1 RB25DET.

For some odd reason my car runs like crap on stock timing. There's just no power up top and it feels really rough. It makes lots of noise but doesn't really go anywhere. But when I set timing closer to 20* BTDC, it feels much better. It has more power and it comes on a lot smoother up top and down low. I know for a 5spd RB25 stock timing is 15* and for an auto stock timing is 20*. But my engine is a 5spd manual. I'm really stumped with this and I don't want to ruin my motor by running incorrect timing. Has anyone had an issue like his before? Any help is appreciated.

Is that +6 degrees over stock timing (21* BTDC). How modded is your engine?

how are you checking your timing? is it possible that you have infact been moving the timing the other way and dropping it to 10*btdc?

also what fuel do you run? if it is crap fuel then that may be the cause. set it back to 15* and put some good octane boost in and drive it round for a bit and see if that makes it run any better.

I'm checking timing with a Snap On timing gun using FSM procedures.

When I was setting timing to 15*, I aimed for the 4th mark from the left on the crank pulley.

For example: l l l l <---This one

0* 5* 10* 15*

I'm running 93 octane fuel (highest grade available here). I'll try octane booster to see if that makes a difference or not at 15* BTDC.

I just went back out for a quick drive. I don't really want to drive too much b/c of my lack of fans. But I noticed that at 15*,17*, and 20* my car felt slow. It honestly felt more sluggish than a stock KA24DE. So in desperation, I rotated the CAS completely counter clockwise (advanced) and went for another drive. It felt great - like a 6 cylinder turbo should. Albeit it wasn't too smooth due to some ignition misfires but it actually felt fast and it knocked my head into the seat. None of this occured at close to stock timing. I'll have to wait to get some fans on before I got out for joy rides again. I don't think I've been doing my engine any good running w/o fans.

One of the things I notice with guys new to RB’s is they tend to point the timing light vertically, straight down at the timing mark on the cam cover. This is wrong, the timing light needs to be 25-30 degrees off vertical, towards the airfilter, (the RHS looking at the engine). If you point the timing light vertically you see about 5 to 8 degrees advanced from where the timing really is. Move the light (and your head) across to the right and you get a better indicator of the real timing.

:) cheers :)

I'm new to RB's but I'm not new to Nissans and timing them in general. Also, I'm a techinician for Honda.

I'm definitely pointing the gun correctly. I also learned that it's easiet from the right hand side. The timing indicator is also easier to see from that angle.

Edited by 240dreams

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

    • I thought it could be an issue because the standard plate was flexing when stressed. Maybe the original gear set will hold a bit better without flex? Last time on the dyno it made around 670nm at the hubs. Now it have bigger turbo and better intake but have not been on a dyno yet. The car is being used from family trips to drag race events. So the shifts can be a little violent. It is grinding if I shift to fast so was thinking I should overhaul it soon.
    • From the factory on RB26s there's a fitting on the intake manifold collector/"plenum" that provides pre-throttle boost signal. That's how they did it back in the day, I figure it's fine to replicate it.
    • I would be surprised if that wasn't the issue. It's probably telling you, that even if you remove the plastic liner, you may have some other clearance issues that may occur too in some scenarios. IE, tyre to guard. It looks like someone has already rolled the lip, but you may still have issues in the future IE, turning and hitting a bump etc. The fact it changes how bad it makes the noise when you are going backward vs forward is highly indicative that it's the tyre rubbing. They do make a terrible sound, even if you're only pushing a project car that has a liner hanging down on a tyre!   Has the car been lowered? If it has been, what is the measurement from the centre of the wheel hub to the lip of the guard straight up?
    • Summernats cruiser?
    • Mark's a bit smarter than people give him credit... He'd convince the person that is to become dead, to drive him to the forest first. That way his car has no evidence in it, and he's free to dispose of their vehicle permanently how he sees fit too...
×
×
  • Create New...