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The astute amongst you will notice something missing from the turbos...the oil catch cans. Guess what? they don't come with the turbos. Only relevant if you already mailed out your old turbos and they had the catch cans on them. Oy, that one hurt financially.
whats the boost do when the boost controller is off? that's how you can check where the gates are set. normally Xona Alphas will be set to 1 or 1.1 bar.
HKS has some offset settings that are tricky to get right. I wouldn't use the TPS modeling function of the HKS and only use the RPM function. First start with setting A and keep it simple raising the boost flat until you reach your desired torque MAX, then switch to setting B and start from value in A. Raising boost with RPM after the TQ peak to keep the HP climbing while holding TQ in check.
You'll have to get comfortable with the HKS because boost control is now on you.
I had expected the gates to be around 1 bar but with the HKS off (i.e. the A B C were not displayed) it still hit 20psi on the pre-throttle body sensor at 4700rpm. The value was a little lower looking at the HKS peak value, which presumably reads the pressure from the plenum itself after the tb.
I guess you are saying that the adjustments should be made on the dyno...otherwise how do you know where tq peak is? With my latest revision the car is fast and smooth. Just want to make sure it's safe too, lol. I'm not planning on pushing it to the bleeding edge...
In 3rd gear it hits 20psi at 4350rpm on wastegate pressure. That's the pressure as read by the pre-throttle body sensor. The car ecu "modelled" manifold pressure is a little lower. I believe the HKS actually reads manifold pressure so I will try to log what is happening in the manifold via the HKS software.
In 3rd gear with a 20psi setting on the boost controller it hits 20psi at 4150rpm. I may try and play with the "offset" function on the HKS but if this was my target anyway I may just leave it alone. It flies!
How soon can you hit 20psi with that HKS in say 3rd or 4th gear? Are you saying 4700rpm? Those turbos look sweeet!
Depends how you ramp in the boost and your PH target. On garrett 30's you hit 20 psi (1.4bar) at 47-4800 if the target is 1.4-1.45 ... When targeting 1.9Bar however you see 20 psi at 4200rpm ....
True! When I changed the target to 20psi it hit it sooner. I think 20psi at around 4200rpm is what I was seeing with the 68s and I don't think I'll aim for any higher in this part of the rpm curve as it is near torque peak. As I look at my logs I'm thinking that my wastegate springs are probably 20psi or even higher. The Tial MVI 2.5 wastegates have springs that could be up to 22psi so it certainly could have happened that I got springs other than the 15psi ones.
Correction, I hit 20psi around 3500rpm with the 68s. I don't know if you can directly translate 20psi on 1 turbo with another because the whole intake plumbing has changed so that there may be a higher volume of air with 20psi with the Xona and larger ypipe and tb than with my 68s and stock ypipe and plenum. Lots to learn here.
Bogg your ecu sensor should read somewhere around -.3psi at idle that's some restriction upstream. I should have been more specific, by vacuum I meant somewhere in the -8 to -9 psi or somewhere in the -18in Hg range. If your hks reads more vacuum than your map sensor then you are reading from the manifold Sounds like you are sorting things out good luck.
Can you give a detailed explanation on how your turbos spool I understand that in 1st and second gear lag is very short due to gearing but who does the car feel in 3rd and 4th ...can you mimic the car to drive like N/A..one of my gripes with vtg that I hate is turbo tip in..would you say that the Xanax are better or woarse...thanks for your comments
John
Can you give a detailed explanation on how your turbos spool I understand that in 1st and second gear lag is very short due to gearing but who does the car feel in 3rd and 4th ...can you mimic the car to drive like N/A..one of my gripes with vtg that I hate is turbo tip in..would you say that the Xanax are better or woarse...thanks for your comments
John
Funny that I tried to correct that spell check 3x...seems like Xanax is drug of choice when your pulling a 800 hp car...does anyone know what’s the difference between 3071-3073-3076..
05-19-2018, 09:44 PM
