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Discussion Starter #1
I finally have my car all back together and am trying to have some fun :) BUT im having an issue with boost. Im trying to get a powerful start from a roll, so in 2nd gear i cruise at 4,000rpm waiting to punch it. I hit the gas WOT and behold, i only get .2 to .3 bar!!! wtf. Now if i roll into it, like if i start at 2,000 rpm and slowly accelerate until i feel the 2nd turbo come online then i can punch it and hit my 1.1bar setting on my AVC-R.

Also, in 1st gear, i can rarely ever get the 2nd turbo online. I usually peak at .5 bar and it just holds that till i shift around 6500, then in the rest of the gears the 2nd turbo comes online just fine.

Another instance, i was comming up to an intersection. crusiing at 50mph in 5th gear, hit the clutch put it in 2nd, brake, turn, gas it and let the clutch out as i exit the turn. im at about 3500 rpm and begin to accelerate, i want to feel a little boost before i shift so i wait fo rit, BUT WTF it doesnt kick in untill 6,000rpm??

So besides the obvious fix of just spending $!0,000 to go single, how can i get my twins functioning properly? thanks guys, Ben
 

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damn...you already stole my idea...but u can do a single for ALOT less then 10k...i pieced mine together with the best of the best...HKS To4r, HKS manifold, BL 4" DP, Greddy 3row with 4row piping, BL feed/return line kit, etc etc for only $4,500.00...take your time n u can find good deals...
 

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Discussion Starter #4
i am in sequential mode. the most puzzleing thing is that this all happens SPONTANEOUSLY. One day its fine, other times it acts like this.

im going to install the e-ttc mod later and next time it acts up ill flip the switch and see if it cures it.
 

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Sounds like you just haven't yet figured out the powerband. It's not a 8.3L Viper so you can't expect to hammer the accelerator and feel instantaneous torque at any point in the RPM curve. That being said, you may have a problem with loose vacuum hoses to your IACV & EGCV VSVs and/or actuators. Check them both, replace hoses, and zip tie them securely. And, btw, a single turbo isn't going to fix the problem of slow spoolup - it'll make it worse.
 

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crossways said:
. And, btw, a single turbo isn't going to fix the problem of slow spoolup - it'll make it worse.
Agreed.

A single turbo, while solving most boost problems and boost frustrations, creates a whole different set of headaches and frustrations from dealing with aftermarket parts and shops in the industry that aren't OEM parts, specs, and procedures. It sucks diagnosing stock turbo boost problems, I totally agree, and it ALSO sucks having to go single also. Both are a pain in the ass. :rolleyes:
 

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crossways said:
Sounds like you just haven't yet figured out the powerband. It's not a 8.3L Viper so you can't expect to hammer the accelerator and feel instantaneous torque at any point in the RPM curve.
thanks for the input, however I think you might have misread my question. At 4,000 rpm i would expect very quick spool up, and the second turbo at least comming online. yet, i only made .2 to .3 bar, that is 2.9 to 4.3 psi. Knowing my powerband has nothing to do with making less than stock boost in 2nd gear at 4,000 rpm to redline. What i am wondering is, why would it only make 4 psi? The second turbo never came online and it seems as if something restricts the first turbo somehow. it hit .3 bar almost instantly, then just held that to redline (which i wanted to go to and see ifit would make more boost)

and yes, i meant going single as a way to get around dealing with the sequentials intricate setup.

thanks again guys :)
 

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i have found that at 4k im to far up in the rpm range to get the turbos to spool right at 4k, if you brake boost you should see an increase in boost pressure
 

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Crossways has already answered your question. There are only two VSV's and two actuators that can effect the second turbo coming online.

"That being said, you may have a problem with loose vacuum hoses to your IACV & EGCV VSVs and/or actuators. "

So check your IACV and EGCV vsv's, the vacuum hoses connected to them and the actuators themselves.

When you break it down like that it is not as hard to diagnose the sequential system as people make it out to be.
 
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