ok guys, i bought my supra a little while back and in the process of building the engine and putting a bigger turbo and what not on i found a little gift hidden behind the glove box. its the HKS vein pressure converter i need to know what the hell is it suppose to do? is it good? everything is hooked up and working in the car so i also need to know how the heck do i tune the thing?? i know that its very rare and they dont make them anymore.
HKS vein pressure converter
- Thread starter drewmiller5007
- Start date
The VPC is used to convert your car from using the AFM to using a MAP based system. So basically, the air is metered from the intake manifold, and not before the turbo. Benefits include being able to remove the restrictive AFM, purge your BOV to atmosphere and not have your vehicle crippled by boost leaks if one should occur. There's really not much tuning that can be done with the unit by itself. Also, just because your car is running fine does not mean that it is in use. Check to see if your AFM is still present and connected. Look for the VPC's pressure and temp sensor in the bay. And finally, not in the least bit rare. True, they are discontinued but pop up in the for sale section several times a month. The PnP harnesses are getting hard to come by though.
the VPC is connected and working i have found the sensors in the bay and there is no AFM on the car at all. as far as tuning? there are multiple knobs on the face for adjustments?
Most just leave them at 12 o clock and use something like the GCC or AFC to tune. I have heard that the idle knob sometimes needs adjustment when it's cold out in order to smooth out idle. Why do you feel you need to adjust it? Is your vehicle not running right? Are you attempting to increase boost and hitting fuel cut? Without a piggyback, AFPR and most importantly a WB A/F, I wouldn't be messing with tuning too much.
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I mean I just got the car and did some upgrades to it bigger turbo and whatnot then I found that hidden and just was seeing what it was so I'm asking "questions" to see if it needed tuned or just getting info on it I guess.
Don't mess with it. like MarkIII said, it CANNOT be adjusted with a GCC. Those computers are few and far between. As long as they are all left in the 12 o clock position everything will be good. I have one in my Supra, and called DriftMotion about it trying to find out how to tune it.....they said the exact same thing " Don't mess with it or it will fuck up the car" lol I tend to listen to people who know more about things then I do.
Find someone who can tune to adjust the knobs as needed. It's a pretty simple system but if you mess with the knobs, you're changing the a/f readings being fed to the ecu which could in turn put you into a lean situation.
Honestly, if you just put on a new turbo you need to get the thing tuned.
Honestly, if you just put on a new turbo you need to get the thing tuned.
The reason you leave the knobs at 12 o clock is because that is the factory setting on the controller. Which fools the ECU into thinking everything is normal. Get an AFPR and an SAFC if you want more control over your ratios. I quote Aaron at DM when I say this next one " If you mess with the knobs on that VPC, you will mess alot of things up. You will need a GCC to tune this car because of the VPC. If you want to be able to tune it more, then get a MAFt or something like that. "