Jump to content
SAU Community

Recommended Posts

  • Replies 47
  • Created
  • Last Reply

Top Posters In This Topic

Good luck with using a smaller turbo - how is that going to fix things? Am I missing something?

If the gasses wont waste - then it is pretty easy to see that there is a problem with the manifold, especially if you know the turbo is a good thing, and the wastegate is a good thing.

It seems to me that if the gasses arent wasting with the wastegate removed, there must be some crazy turbulance happening (high pressure and low pressure systems, you probably got a whole weather system happening in there!...j/k). If this has happened already, it would be pretty hard to believe that all the rest of the manifold is a good thing - manifold design is pretty critical to optimum performance.

Sorry to say this, but I believe the only real solution would be to ditch the manifold you have and get a new one - one that has proven results and works, especially if you have evidence of its performance with a similar sized turbo/engine combo.

Good luck. I have had to cut my losses in the past, sometimes its the only way.

There certainly is alot more to getting the best out of a turbo setup than it appears on the surface. Even a change of a couple of mm in pipe diameter in a manifold can make a noticeable difference to response and driveability, seen it with my own eyes - its tricky business. No wonder an experienced mechanic/tradesman likes to guard hard leant secrets and charge a few dollars more than the local autotune fellas - and so they should, its expensive business.

My motto: the good feeling of a well done job lasts alot longer than the smile you get from saving a few dollars - fortuneately there are places around like SST and Performanz that do put in the extra, learn lessons the hard way, and are able to guide noobs like me when things go cactus. Could you imagine what would happen if you took a problem like this to your local garage mechanic:)

anyway, my 0.02c

And Ditto on the manifold photo request, 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

    • Dort sounds above 3k rpm are dorty 🤣 I might krinkle black the alloy 🤔
    • It makes you wonder, all these people starting to make a billet replacement head, I wonder if any have thought about trying to adapt tech from newer engines into them. You're already at the full design stage to make a billet head... Why not really spice it up and had some more modern tech into the mix too...
    • Connect all the plumbing up properly. The actual worst part about having the turbo unable to actually build boost, is you can and likely would over soon the turbo if you drove the car (free rev while stationary isnt likely to manage it).   If you do have an air leak as Duncan suggested, you'll have a bad time as the AFM will be saying different to reality.   As you have had the engine out, I'd go over all electrical connections again. If you have a consult cable, plug it in, and see what the ECU thinks is going on. Did you touch the timing belt? If so, double check your timing on the gears is correct AND put a timing light on it while it's idling and see what ignition setting you have. Is the AFM you've installed the one that was in the car previously? You said you replaced seals, what seals exactly? What have you had apart?   From memory when I had my RB25DET with factory throttle, there was two plugs the TPS plug on the loom could go to. One would leave the car running like shit, the other made it work, I think one plug on the TPS area was for something else (an option). It's too many years since I saw that part of the loom to remember properly though.   Is the car idling smooth (as smooth as an RB can)? Does it smell fuelled up?   I have a feeling either timing in timing belt is off, or a sensor isn't right.
    • Theres still skid pan and motokhana days up in QLD at least that are $100 or less. The ones that are ran as "driver training" less so, they're expensive, but just normal skid pan days like SAU ran are still low cost. And thats one of the places I learned to be a lariken, purely by asking for passenger rides, and how people were doing crazy things. Reese gave me plenty of pointers back in the day for skid pan! And yes Duncan, I will never forget your pointers for track work. Especially after Neil got out saying "I am NEVER getting in the car with him again!" 😛
    • 49719 is the cooler loop. Right at the front, LHS of that diagram. Return line from rack (LP side) goes to cooler loop on RHS front of car, then back under engine and returns to bottom of tank. 49717M is feed from tank to pump. HP line out of pump is thick rubber, followed by the hard line that runs down to crossmember and runs in parallel (but opposite flow direction) to the LP return line. Nothing goes anywhere near the firewall or interior of car. The closest they get to that is the connections on the rack.
×
×
  • Create New...