Boost Pill, is it needed ?

[gmogle]

Guys,

Having a few problems with my car after I have had a large amount of work done on it.

Had new injectors fitted, plus fitted HKS Racing Suction kit and 2nd hand boost controller (Greddy Profec).

Now when I am driving along if I drop the gear and accelerate hard it boosts at about 0.75-0.8 (with boost controller switched on) if I lift off the accelerator then plant my foot again it will only boost at 0.5 bar and then when I take my foot off I hear a noise kind of like if air has been trapped somewhere and its coming out. If I let the revs drop down to under 3k and then accelerate it does so but as you get passed 5,500 revs the boost seems to go down to about 0.6-0.7 and then it goes back to 0.7-0.8 and stays steady. But next time get the problem above.

If I turn off the boost controller the car will only make 0.5 bar and I get the funny sound of air again when lifting off.

I have a dump valve on the car and since I have had work done it doesnt sound as fierce as it was or as loud.

Taken apart the induction kit and hoses coming off it, made sure they are all nice and tight and fitted new clamps and pipes in some case, checked round by the plenum at the pipes coming from under there and put tie wraps on those that I could move up and down (in and out of the green/cream look like check valves)

So my next step is with the boost controller, now I have disconnected it but cant find the pipe that contains the boost restrictor pill (the pipe going from the actuator to...not sure). Am I safe to use another piece of pipe without the pill in to see if the car makes more boost than the 0.5 or am I likely to have the car overboosting dangerously? Would a slightly small diameter pipe have the same influence as the boost pill ?

I cant honestly say whether I have had these problems since the injectors were fitted (cars ecu wasnt mapped fully so I wasnt thrashing it) or since I fitted the induction kit and boost controller.

Its really starting to upset me now, I have been advised to look under the inlet plenum for a split vac pipe. Is this the most likely culprit do you reckon ?

Cheers for any help re the restrictor pill and the vac hoses etc.

Gareth

[gmogle]

Right, been out again waking up the neighbours lol it seems that if I accelerate hard into the 2nd turbo (it is boosting 0.8-0.9 on boost gauge) then let off and put my foot back on the accelerator it only makes the 0.4 boost and then letting off again produces this weird air pressure noise. If I let the revs reach 3000rpm and then accelerate it seems fine.

I have tried fiddling with the boost controller settings, turning the balance up and down to see if this made a difference but no although I get better response when the balance is above 50%.

Also then tried fiddling with the boost settings, this was the high one and even if I turn it all the way down it still makes the same 0.8-0.9 bar boost. Now I would have expected to see this be lower if I\'d set it lower ?

Forgive me if I am being dumb here but please help. Want to understand if its the boost controller first before I start on the vac hoses under the inlet plenum.

Cheers,
Gareth

[Fats]

how have you got your boost controller pipes setup, have you routed the boost controller to the wastegate only or both pre control and wastegate.

Cheers
Andy

[gmogle]

Its only to the wastegate mate, read a large number of posts on the rx7club forum about both and the wastegate only method seemed favourable.

Gareth

[Fats]

cheers mate, i was getting mixed results too, will try and get it fitted in soon!

[m4drx]

got the same problem and the same controller almost certain its the greddy!,

any luck with yours?

[m4drx]

really really really want to know!!!

[probedb]

Do you need the pill if you\'ve got a controller? I thought it was for the stock turbos when do boost controller is fitted? Might be getting crossed wires tho.

[m4drx]

well i have taken the boost control valve off the greddy and put the tube back to where it should be i think and i still have major hesitation and does not boost properly at all!

[m4drx]

if forced to boost doesnt even make enough to go on to both

[turbotink]

if its like a howling noise when you come off oost i had a check valve that was dead till pip fixed it for me.duno where that valve is or anythying but might help a little bit lol.

[m4drx]

replaced all check valves, couplers, spark plugs, intercooler leads, visable rats nest piping (withour plenum off),even taken the greddy boost control valve off with no change.

now only makes 0.5 boost if forced but hesitates like mad no transition

[probedb]

Here\'s a guide to installed a Profec B Spec II. Should help you with what everything does and where it goes...

http://www.rx7club.com/forum/showthread.php?t=192249

You might need to register but it\'s an rx7 forum anyways

[Jit]

did you have a boost pill in the two lines then? or did you remove it?

[m4drx]

i have the manual for mine so i disconnect the parts that interfear with the control system and only left the sensor so it acts only as a boost gauge but still no luck