legendr35

Hello,


I get full 10-8-10 when I gradually floor the my car in each gear except first. First will only get around 6-7, and by that time I have to shift already, so I think this the normal.

But when I want to drag race, first gear pulls around 6-7, then second gear pulls around 7, then 3rd gets about 8, and then 4th get around 8-9.

Is this normal?

Shouldn't I be getting full 10-8-10 boost in 2-4th gears?

thanks!

legendr35

anyone?

mr_jonboy

Is it like when you shock (quick punch) the gas you get real low boost?

legendr35

hi,

I don't get really low boost, but when I do quick punch it, it doesnt go full boost.

mr_jonboy

Well I had a this problem that when ever I would stomp the gas (usually right after a quick shift, say from 1st to 2nd or 2nd to 3rd) the boost would lock at like 3-4#. But if I would let off and ease on the throttle it would build all the way to max boost. Does this sound similar to your prob?

legendr35

hi,

almost exactly, but i don't get 3-4, i get more like 6-8....

legendr35

p.s. i ran a 14.0 in the 1/4 with this problem, without a good launch.

mr_jonboy

If you want to diagnose the stock system you can. I believe it was a solenoid on mine. The turbo or precontrol solenoid, one of the two. They are the two solenoids that are bolted to the front of the intake manifold just under the black pressure tank in the middle of the engine. (check workshop manual). I believe these solenoids are very pricey from the dealer like 100-200 apiece. I was told that a boost controller would fix the problem b/c it gets away from using the stock solenoids. I got the Apexi AVC-r and haven't seen that problem since. Now tuning the BC is another story, but there is always something, right...

BTW, when I first got my BC, b4 it was tuned, I had the BC off meaning it uses the wastegate only for boost control and will only allow 7 psi of boost. My 2nd turbo wouldn't kick in sometimes b/c 7 psi is the engagement point for it. Sometimes it would kick in at like 6500 instead of 4500. But anyway, with that I beat a Cobra (low 14 sec. car) from about 30mph to 125mph. The guy was amazed , gave me compliments. I just told him that my car wasn't running right and I should have another 40-50 hp and I still won. He just laughed. His GF just smiled.

legendr35

thanks for your help...what type of boost controller should I get? I don't need one with insane amounts of functions, just to help this problem, nothing else. (essentially a cheap one )

Toadman

Could be the rubber coupler also. Easy boost buildup doesn't allow a crack to leak, but stomping on it would split it wide open..

mr_jonboy

Usually cracks are shut at low rpms and open up at higher rpms due to higher flow rates.

I have the AVC-r but it has a lot of extra goodies on it so it might not be what your looking for. You are probably going to pay close to $300 for a cheaper one anyway if you get electronic and electronic is what your going to need to get away from the bad stock solenoids.

pweizman

Mr_Jonboy..


So, you are using an AVC-R to control boost on your twins?

I didn't think that was possible.

Could you explain how you have it hooked up...and what you can do with the AVC-R...like:

fuel adjustment, boost adjustment, max boost...etc

mr_jonboy

Well I am not the only one on here with that BC on the twins. The manual that comes with the BC even has pictures of the stock twins on the FD to help installation. Rob's site has very good instructions on setting the AVC-r up in terms of boost levels, etc. The AVC-r is not a fuel management tool. Apexi has another piece for that besides the Power FC. The AVC-r is basically just a very high end boost controller (boost per rpm, self learning functions, etc.). I even have mine set up with the scramble boost feature which allows more boost at the touch of a button. But really can't use it until the ECU gets here.

nrolfes1

just getting a boost controller wont' fix your problem, but you can get one from hardware store for about $2.50. a needle valve manual controller, i think theres info on it at robinettes site or lightning site.

mr_jonboy

Well it depends on what his problem is. If his problem is the same as mine was then getting an electronic BC will fix it. Getting a manual BC that uses the same stock solenoids will allow him to control max boost but he will still have the problem he is having.

Check the shop manual in the troubleshooting area, that is what I did.

bhodge

I am having similar problems with hard acceleration. I also have a home depot controller and it will not fix that problem. So my question is, does an electronic boost controller actually replace the solenoids on the intake manifold?

mor

I had the same problem that you were experiencing until I installed my Profec B Spec II boost controller on Saturday and now the boost is very consistent and predictable.

Note, I installed the boost controller to handle both wastegate and pre-control actuators eliminating both solenoids.

Also, before I installed this I thought my problem was with the turbo control actuator because on KOKO, the actuator would only jiggle/flinch instead of pull in. I think I still need to check this but at least I'm not having the problem you're experiencing now.

Greddy Profec B Spec II is about $300 brand new on eBay. Just search for "Profec" and make sure to get a Profec B either spec will do.

Hope this helps.

apneablue

I had this same problem...Mine was a broken check valve...The one right under the pressure chamber...Mine came apart at the seam. I glued it together and it worked but I had it replaced with a new one after a couple of weeks... Hope ya find it.