Jump to content
SAU Community

Recommended Posts

I have a 1994 R33,

I just turn my boost up to 11 pound using a single stage turbo smart boost controller. Since then I am having a problem with flat spots between 4,000 and 5,000 rpm. A mate of mine said that the R33's have factory boost limiters maped into the computers?

An suggestions would be helpfull.

Thanks...

Super AirFlow converter.. by Apexi.. it hooks into the oxygen and air flow meter sensors of the car and into the ECU .. basically a correction factor so the ECU "sees" less or more air than actually going in for each rev range. With a different reading "seen", the ECU adjusts the fuel mapping accordingly resulting in a richer or leaner mixture than factory. This generally can be used to give the car a 20-30% power increase with the right tuning.

Its what you use when you don't have a full aftermarket computer (around $1000 more) where the fuel maps (and other things) can be adjusted internally a lot more accurately. Hope that helps.

Thanks for your reply,

I was going to buy an after market computer. By reading your post above it looks like that will solve my problem.

Ps, Is it true that the standard R33 computer has a over boost restricter? because the problem only exists at 10 pound and over

Hi GunMetalR33, the issues and solutions are;

1. Over boost protection, the ECU cuts fuel and ignition when boost goes over 11 psi. Solution device called boost cut defeater. Cost a couple hundy.

2. 180 kph speed limiter, the ECU cuts fuel and ignition when the speed goes over 18o kph. Solution device called speed limit defeater. Cost a couple hundy.

3. Fuel mixture enrichment, the ECU increases the fuel supply as boost increases. Solution device called SAFC as explained above. Cost a few hundy.

4. Ignition timing retard, the ECU retards the ignition timing as boost increases. Solution device called ITC similar to SAFC except it modifies the timing signal such that the ECU does not retard the ignition. Cost a few hundy.

So if you add all these together you will find that the total cost ends up more than a Power FC. Particularly if you can pick up a used one. If you want to fix all of these issues we always recommend the PFC, if you are happy missing out on more than one fix then maybe the SAFC is worthwhile.

Hope that helps

Andrew (Jayson here :) ),

I was just thinking, it could be the gap in your plugs !!!

Damn, if I would've thought about that last night we could re-gapped them then :P

Seems your car is one of the rare ones that are totally stock, I'd say your plugs are still gapped at 1 or 1.1mm !!

Damn (hitting myself in the head), I should've thought about that !!

Cool, we can re-gap your plug's a little on the weekend and see how it goes?

J

  • 3 years later...

my car was stock.. but shite, after putting on exhuast and fmic... YOU CNT GO BACK !!!, soooOOOo much more efficient, seriously that smic is sooOOO shithouse its not funny....

Sorry I am new to forums & Skylines, what does SAFC mean?

ha ha ha, I cant believe I asked this type of question :)

Its amazing how much you can learn from this forum... I went from "What does SAFC mean" to installing after market ecu, turbo, injectors and clutch etc :)

man, this takes me back to the first couple of weeks that I had the car :)

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

    • Oof, I will forevermore have those shredded gears in mind whenever someone talks about showing mechanical sympathy towards their car. Thanks for the photos, fascinating stuff!
    • Curious to see how the SpeedTek stuff holds up
    • The holdups last year were drivetrain related. I had the car out right after getting the bearing issue resolved. Third launch and the car didn't move after releasing the clutch. It had sheared all the engagement teeth off the 1st gear.    Thankfully no other damage was done. I set an aftermarket gear beside an OEM gear and found that the engagement teeth on the OEM gear were much larger and better supported. Looking through my bin of spare transmission gears I found that there are two types of tooth on the OEM first gears - the larger tooth and the smaller tooth. It looks like most aftermarket gearset manufacturers base their design on the smaller tooth. OEM large tooth left - Speedtek, OS Giken, etc or OEM small tooth right Decided to give that larger engagement tooth a try. Pressed the ring off an OEM gear and sent it to a transmission manufacturer here in the States. They did their "faceplating" operation with my synchro ring on the Speedtek gear.   I reassembled it, took it back to the track and promptly destroyed the gear itself.  I'll rebuild this and use it as a spare - thankfully just first gear and the countershaft are damaged beyond repair. Definitely disheartening but my welded on engagement tooth ring held up!  Moved to Speedtek's dog engagement design as the gears appear to be much stronger. So far they have taken much more abuse at the track. Also scored a Stillway lockout from the Netherands for super cheap. It's for some other RB transmission so it took a bit of fabrication to fit but honestly a very easy job. I also had to heavily modify the gates as they were very different.   Then for some reason at the last test and tune a silicon coupler below the throttle blew off and took out the radiator and fan. Thankfully it was in the burnout box and not down track. This car is really beating me up - I still haven't made a pass in it. Ran it through the gears many times on the street but it keeps biting me at the track.  Currently in the process of replacing the radiator and remaking the throttle pipe to remove the coupler and use a cast 90 and a vband. I WILL get this thing down the track...
    • Covers most of the above points really. There's a few exceptions but most just see driving as an irritating but necessary task they must complete if they want to get anywhere on time. Also see it as a good time to show their awesome multi-tasking abilities on their mobile and/or doing their makeup.  
    • I don't believe I posted pictures of the second oil pump pickup I added so here they are. Data shows it gets oil pressure up to the relief pressure much earlier in the RPM. Is that important? Not likely... This was just another attempt to fix the bearing issues.   I also heavily opened up the inlet to the pump since it now had to flow oil from two pickups. I believe the diameter increased about 1/8".
×
×
  • Create New...