Jump to content
SAU Community

Recommended Posts

I have an issue with my R33 S1, I am running a Highflowed turbo with FMIC and standalone Haltech ECU, I have done some other minor mods like custom cold air and 740cc NISMO injectors yet I keep finding that on the dyno at 14psi I am backfiring around the 4000-5000rpm range? now this happening in any gear and well the system is showing that the engine is getting enough fuel and air. Does anyone know what else it could be? could the valve springs be a bit soft?

I want to run up to 18psi yet I am unable to with the current predicament?

HELP!

Aridyne :)

Link to comment
https://www.sau.com.au/forums/topic/65477-backfires-help/
Share on other sites

tried shortening the plug gaps ? 4-5k RPM is about where they usually blow out unless gapped down.

I'll give that a go. I am heading down to see my baby today so I should have a looksie at these and work it out.. could it be anything else? As it does idle a little rough and doesnt normally start first up in the morn and needs some tlc to get going

Link to comment
https://www.sau.com.au/forums/topic/65477-backfires-help/#findComment-1223720
Share on other sites

Well we've tried that and still its happening, so we are going to use a 3bar Map sensor for the Haltech and see if that helps as the haltech 3 bar map sensor is actually meant to be used when going over 15psi.

I am still at a loss as what it could be.. I am going to downsize the injectors to help with the idle to 550cc Sards.

Will sell the 740cc's ones.. as I have only had them in the car for 1 month and well they are just to big for my applications at the moment..

Link to comment
https://www.sau.com.au/forums/topic/65477-backfires-help/#findComment-1224003
Share on other sites

I read in a previous thread somewhere, it may have to do with your crank angle sensor but I read it while ago and I might be completely wrong, but another avenue that you can explore/check.

Well that could be a option, I will have to check and see.. I thought it might be the valve springs myself at one stage but who knows.. its a tricky subject for me.

Link to comment
https://www.sau.com.au/forums/topic/65477-backfires-help/#findComment-1224290
Share on other sites

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

    • Sounds like you've got an interesting adventure ahead here with local support if you have trouble! My guess is that, unboosted, you will be OK with a small upgrade like -9. What will happen is that once the stock ECU sees more airflow than it expects it will add a heap of fuel and pull a heap of timing to be safe because it can't understand how it could get that much air without there being an issue. You will see clouds of black smoke and it won't pull hard through the midrange and top end. So, overall it will be a bit frustrating but should be OK. If you are still nervous set the base timing back 2o through the CAS, but it will be even more sluggish everywhere. As said above through...this is not my guarantee your engine won't be blown into a million pieces, leaving you looking for very hard to find parts A better idea is get a computer with logging ASAP, wire in a wide band O2 sensor and a use remote tuner. I've done multiple cars this way and while it is not as good as a specific tune on a dyno they can get it 90% right. I'd suggest if you can afford an R33 GTR these days you can afford an ECU and tune. And if you can't afford that you sure won't be able to afford the rebuild if it goes bad in the meantime,.  
    • Yeah it would be nice if someone took the time to put that sort of information together, but there are a lot of variations in looms. I think you are making this way hard for yourself if you just want to get it running....sourcing an SR20 with the right wiring will be a billion times easier than matching the RB loom to an S15 chassis. If you do end up going this way, you just need to trace every wire in the loom with a multimeter, 95% of them will go to a location you can confirm at the ECU.....and then post it up for the next person who needs it  
    • Just top it up with water, and keep a general idea of how much you added. It is normal for water to be pushed into and pulled out of the reservoir through the cap, and it should not be more than half full or it will be likely to overflow when hot. Any decent mechanic can do a pressure test of the cooling system to confirm if you have a leak. Keep in mind if it is only leaking a little and when hot it may well evaporate before you see it hit the ground
    • I'd ask the shop what they used and use that. Mixing coolants is sometimes OK, sometimes not, and you have know the details of each coolant to know whether it's a good idea or not.
    • Is it alright to top up with just another green coolant?
×
×
  • Create New...