Jump to content
SAU Community

Recommended Posts

How much spike

It feels like as it ranps up it hits the over boost warning/limit so it bleeds some off, then does it again.

It's enough to think the driver gets on the loud pedal then backs off then nails it again.

It feels like as it Tampa up it hits the over boost warning/limit so it bleeds some off, then does it again.

It's enough to think the driver gets on the loud pedal then backs off then nails it again.

It does not do it the second time now, similar the first time, maybe a bit earlier, just after 4000rpm

Going out in early the morning if it is sunny to see how the glare is with that dash mat and will give it a good run and keep a better eye on it

Would the same spiking situation be happening if the HKS boost controller was controlling the boost, I am not changing anything, just wondering ?

Short answer to this is yes, it would still spike, but then all you would do is decrease your duty cycle.

Don't how the haltec does it but I assume it just controls a mac valve, so your tuner just needs to start the bleed off later if its just spiking as boost is ramping. It just makes it a bit less aggressive.

If you are using an external wastegate with both ports being used, an old school way is just crimp the vac line going to the top port with a hose clamp just enough to restrict flow, or put a bleed valve in that line and bleed it off. In both cases the top chamber will have less pressure and reduce your boost, and can be adjusted when ever you want without really messing up your ecu if its just setting fixed parameters to a mac valve's duty cycle and gain.

Short answer to this is yes, it would still spike, but then all you would do is decrease your duty cycle.

Don't how the haltec does it but I assume it just controls a mac valve, so your tuner just needs to start the bleed off later if its just spiking as boost is ramping. It just makes it a bit less aggressive.

If you are using an external wastegate with both ports being used, an old school way is just crimp the vac line going to the top port with a hose clamp just enough to restrict flow, or put a bleed valve in that line and bleed it off. In both cases the top chamber will have less pressure and reduce your boost, and can be adjusted when ever you want without really messing up your ecu if its just setting fixed parameters to a mac valve's duty cycle and gain.

It is an easy fix through the Haltech, just a little less aggression. I thought it was sorted ?

I was just wondering if the boost controller would just stop it before it spiked as it would be set to whatever, say 25psi and just limit it to the 25psi ?

It is all VOODOO to me :/

It is an easy fix through the Haltech, just a little less aggression. I thought it was sorted ?

I was just wondering if the boost controller would just stop it before it spiked as it would be set to whatever, say 25psi and just limit it to the 25psi ?

It is all VOODOO to me :/

The haltech would be doing that, the problem is that you can't turn the boost down when you see over boost on a cold day. That's why I suggested a bleed valve on your top wastegate port. Speak to your tuner to see if its an option as its easy to install. Edited by XGTRX

The haltech would be doing that, the problem is that you can't turn the boost down when you see over boost on a cold day. That's why I suggested a bleed valve on your top wastegate port. Speak to your tuner to see if its an option as its easy to install.

Will do, thanks

Fyi the high boost borg warner EFR cannister will yield 17 psi right at 4k rpms rolling in 3rd straight off the cannister and settles at 16.5 or so. But this is as low as it goes in the midrange at 3 turns in (lowest recommended setting). After 7k, however, boost will drop steadily down to 13 psi at 8000. This is with NO BOOST CONTROL.

I started with boost control yesterday and found that with closed loop starting to bleed 100% up until the control point (3 psi before target for me), the boost will hit 17 psi at 3750! I'm going to start tweaking that today on top end to get solid boost control. Should be easier to trim that now and I'm going to closed loop boost control as well.

  • 2 weeks later...

Alright, I'm reading all of this and getting a little excited.

I'm going to have on more play around with -9s and see what we can get (want more response, want a bit more excitement) and if that doesn't work will look at going single.

Piggaz been in my ear so here I am.

7670 in 1.05 on an internally stock rb26, stock cams (with gears) and all the usual supporting mods. Yes or no? What power will it make and how responsive will it be.

Has Haltech pro plug in, is flex fuel and runs mostly on e85 as it's a weekender.

Friend of mine just tuned his Evo 7 with a 7670 with 1.05 turbine. Motor is a Built high comp 2L. His clutch started slipping so he capped it at 380kw with 27psi by 3900 & was making around 570nm of torque by 4400 (from memory) he said the car drove like a stock turbo evo on the road.

Guest
This topic is now closed to further replies.



  • Similar Content

  • Latest Posts

    • OK, so regardless of whether you did Step 1 - Spill Step 2 - Trans pan removal Step 3 - TCM removal we are on to the clean and refill. First, have a good look at the oil pan. While you might see dirty oil and some carbony build up (I did), what you don't want to see is any metal particles on the magnets, or sparkles in the oil (thankfully not). Give it all a good clean, particularly the magnets, and put the new gasket on if you have one (or, just cross your fingers)
    • One other thing to mention from my car before we reassemble and refill. Per that earlier diagram,   There should be 2x B length (40mm) and 6x C length (54mm). So I had incorrectly removed one extra bolt, which I assume was 40mm, but even so I have 4x B and 5x C.  Either, the factory made an assembly error (very unlikely), or someone had been in there before me. I vote for the latter because the TCM part number doesn't match my build date, I suspect the TCM was changed under warranty. This indeed led to much unbolting, rebolting, checking, measuring and swearing under the car.... In the end I left out 1x B bolt and put in a 54mm M6 bolt I already had to make sure it was all correct
    • A couple of notes about the TCM. Firstly, it is integrated into the valve body. If you need to replace the TCM for any reason you are following the procedure above The seppos say these fail all the time. I haven't seen or heard of one on here or locally, but that doesn't mean it can't happen. Finally, Ecutek are now offering tuning for the 7 speed TCM. It is basically like ECU tuning in that you have to buy a license for the computer, and then known parameters can be reset. This is all very new and at the moment they are focussing on more aggressive gear holding in sports or sports+ mode, 2 gear launches for drag racing etc. It doesn't seem to affect shift speed like you can on some transmissions. Importantly for me, by having controllable shift points you can now raise the shift point as well as the ECU rev limit, together allowing it to rev a little higher when that is useful. In manual mode, my car shifts up automatically regardless of what I do which is good (because I don't have to worry about it) but bad (because I can't choose to rev a little higher when convenient).  TCMs can only be tuned from late 2016 onwards, and mine is apparently not one of those although the car build date was August 2016 (presumably a batch of ADM cars were done together, so this will probably be the situation for most ADM cars). No idea about JDM cars, and I'm looking into importing a later model valve body I can swap in. This is the top of my TCM A couple of numbers but no part number. Amayama can't find my specific car but it does say the following for Asia-RHD (interestingly, all out of stock....): So it looks like programable TCM are probably post September 2018 for "Asia RHD". When I read my part number out from Ecutek it was 31705-75X6D which did not match Amayama for my build date (Aug-2016)
    • OK, Step 3, if you need to remove the valve body, either to replace it, the TCM, or to do a more complete drain.  First, you need to disconnect the TCM input wires, they are about half way up the transmission on the drivers side. One plug and the wires are out of the way, but there is also a spring clip that stops the socket from sliding back into the transmission. On my car the spring clip was easy to get, but the socket was really stuck in the o-ring of the transmission housing and took some.....persuasion. You can see both the plug to remove (first) and the spring clip (second) in this pic Incidentally, right next to the plug, you can see where the casting has allowance for a dispstick/filler which Nissan decided not to provide. there is a cap held on with a 6mm head bolt that you can remove to overfill it (AMS recommend a 1.5l overfill). Final step before the big mess, remove the speed sensor that is clipped to the valve body at the rear of the box.  Then removal of the Valve Body. For this the USDM Q50 workshop manual has a critical diagram: There are a billion bolts visible. Almost all of them do not need to be removed, just the 14 shown on the diagram. Even so, I both removed one extra, and didn't check which length bolt came from which location (more on that later....). Again it is worth undoing the 4 corners first, but leaving them a couple of turns in to hold the unit up....gravity is not your friend here and trans oil will be going everywhere. Once the corners are loose but still in remove all the other 10 bolts, then hold the valve body up with 1 hand while removing the final 4. Then, everything just comes free easily, or like in my case you start swearing because that plug is stuck in the casing. Done, the valve body and TCM are out
    • OK, so if you are either going for the bigger fluid change or are changing the valve body which includes the Transmission Control Module (TCM), first you should have both a new gasket 31397-1XJ0A and a torque wrench that can work down to 8Nm (very low, probably a 1/4 drive one). You can probably get by without either, but I really didn't want to pull it all apart together due to a leak. First, you now need that big oil pan. The transmission pan is 450 long x 350 wide, and it will probably leak on all sides, so get ready for a mess. There are 24x 6mm headed bolts holding the pan on. I undid the 2 rear corners, then screwed those bolts back in a couple of turns to let the pan go low at that end, then removed all the middle bolts on each side. Then, undo the front corner bolts slowly while holding the pan up, and 80% of the fluid will head out the rear. From there, remove the remaining bolts and the pan is off. You can see it is still dripping oil absolutely everywhere...it dripped all night.... I got another couple of litres when I removed the pan, and then another few when I removed the valve body - all up another 4l on top of the 3 already dropped in step 1.
×
×
  • Create New...