St-205 Boost Issue

[GT4 James]

Hi all, have recently been "fiddling" with the motor, had some advice on de-activating the tvsv valve. I followed instructions to the book and after completing found that was only boosting 10psi through all gears, found out this is what happens when no form of boost control (electronic or manual) is installed....makes sense only i have an electronic boost controller....worrying yes i know. Came to the conclusion that the boost controller was probably a bit pants and didnt work, took it off and installed a manual bleed valve, courtesy of my friend from his Nissssssannn 200sx. Hey presto with a bid of fiddling had her boosting roughly 17psi through all gears....very big smiles all round. Sadly he wanted his bleed valve back, so i got another, different design but one designed with the use intended. Fitted this and instantly noticed nowhere near as much oomph(around 11 psi). So done the obvious and wound it out....(ps i have an electronic psi read out in the car) was hitting 12ish psi. Thought ok wind out more....basically cut a long story short have wound this damn this out until its almost on its last thread and car only hits 14psi tops, and isnt so energetic about getting there neither. Have fiddled about with it, had it on and off opened it up checked no debris inside, just isn't the same. Am i right in presuming this is just some pants bleed valve and that I should invest in one like my mates (his is the brass looking style one) or could there be an underlying issue, seems weird this is the only thing i have changed. Any ideas or recomendations as to what to get....please i do know that electronic is the best way just have got £300 spare this second for a blitz spec II which is what i intend to get so this is a nice way of achieving what i want for now. Any help at all guys....sorry to rabbit on lol just a shame to go from such a massive difference to emm a bit pants really. (Substitute the word pants for any of your liking throughout lol) B)

[paulgtt]

I think the problem is that its a bleed valve, ie it bleeds the boost off. Does it have three outlets??

If so then you want to install a relief valve, this doesn't bleed boost so you get the full whack. Ive just installed an R-Spec relief valve to my st205 and it holds 1.1bar (16psi ish) of boost solidly all the way to the redline. Its as good as a £300 odd quid electronic one tbh.

[Fawbs]

This is the one i used mate, worked fine.

http://cgi.ebay.co.uk/MANUAL-BOOST-CONTROL...id=p3286.c0.m14

http://turborevs.org.uk/turbo-and-boost-ki...roller-kit.html

Think mine was from turborevs on eBay but i think they are all the same, 20quid, winner. Good work on the DIY james you are on your way to mod heaven.

Mike

[GT4 James]

Hey cloqwise thanks for that mate. Yeah it does have 3 ports on it so am guessing its a relief valve....could you simply block off the 3rd port?? I will wait for some advice on this before i try lol just incase it overboosts hard or something.

[paulgtt]

No if its got three ports its a bleed valve, the 3rd port, the one at bottom, bleeds excess pressure away hence why your not hitting 16 psi or whatever it is.

A relief valve doesn't have a 3rd port hence the pressure stays within and will give you the maximum boost pressure.

This is what Ive got on mine:

http://www.rspec.co.uk/index.php?main_page...products_id=206

It has the turbo and actuator ports and the adjutment screw and thats it, it doesn't "bleed" off boost.

This relief valve holds 1.1 bar solid all the way to the redline, highly recommend one ;)

[GT4 James]

No if its got three ports its a bleed valve, the 3rd port, the one at bottom, bleeds excess pressure away hence why your not hitting 16 psi or whatever it is.

A relief valve doesn't have a 3rd port hence the pressure stays within and will give you the maximum boost pressure.

This is what Ive got on mine:

http://www.rspec.co.uk/index.php?main_page...products_id=206

It has the turbo and actuator ports and the adjutment screw and thats it, it doesn't "bleed" off boost.

This relief valve holds 1.1 bar solid all the way to the redline, highly recommend one ;)

Ok Paul thanks for the advice, been looking into this and i think the internals of the relief and bleed valves are diffrerent so probably just blokcing off 3rd port wouldnt be a good option. Thanks again buddy. Any advice on good mods to do to the gt-four, been speaking to cloqwise who knows no end on these cars and want all the advice i can get, is a project in progress. Thanks mate

[Fawbs]

Mate i know bugger all compared to some people ha, i'm only on my first rebuild, before i took the engine out, my car was probably similar spec to paul's. At the rate my rebuild is going she won't be running again for years ha, !Removed! postal strike is holding up my leg puller.

Mike

[Fawbs]

Thats my engine bay before i took everything out, might give u a few ideas but try avoid using my intercooler piping route as i had to use this route cause i didn't clock my turbo. As you can see it runs over the hot parts of the engine, isn't the best. Try avoid putting the crank ventilation pipe back into the turbo as it coats everything in a black oilie film, it doesn't need to be re-circulated back into the turbo.

Mike

[paulgtt]

I would say mine is approx 290 maybe 300bhp.

I have a Blueflame catback exhaust (2.75" bore)

Relief valve @ 1.1 bar

Straight intake with Green filter

Blitz Access ecu

This is my engine bay:

And what it looks like after putting the heat lagging on and heat shield for the air filter:

Was going to fit a FMIC but I really need to start saving for a new gearbox, oh and a house

See you went for the same intake setup as me Mike ;)

[GT4 James]

I would say mine is approx 290 maybe 300bhp.

I have a Blueflame catback exhaust (2.75" bore)

Relief valve @ 1.1 bar

Straight intake with Green filter

Blitz Access ecu

This is my engine bay:

And what it looks like after putting the heat lagging on and heat shield for the air filter:

Was going to fit a FMIC but I really need to start saving for a new gearbox, oh and a house

See you went for the same intake setup as me Mike ;)

Very very nice guys im liking the look of both them engine bays...tasty and given me some ideas. How difficult was it to relocate Battery so you could have the straight intake there? Either of you guys have quarter mile times for your beasts?

[Fawbs]

I can give you a list of what u need tomorrow and some pictures, its pretty cheap to do, its easier if u have removed the air con system to reduce weight as you can use the holes in the bulkhead to route your cables. The only challenge is coming up with some way of securing it in the boot

[paulgtt]

I made up a custom bracket to move the Battery back to where the airbox was, mounting onto the gearbox mount and into the wing, no need to extend wiring either if doing it this way. I don't like the idea of putting the Battery in the boot as I need the space.

My best 1/4 mile is 14.2 @ 95 mph and thats with no boost controller, no heat lagging and a gearbox that doesn't like 2nd gear much!!!

Going to Santa Pod next Sunday (18th) still got the same gearbox but now have 1.1 bar in all gears so should be good for a low 13.

[Fawbs]

Just had an idea paul the bloke in the hangar next door to me is going to make me a carbon fibre cold air box for a few beers, if you want i'll see if he can make 2 and see how much it will cost. Doesn't cost us anything for the carbon fibre, won't be doing it for ages yet but if you want one in the future just let us know as you're only down the road.

[paulgtt]

Sounds good mate, il be up for one ;)

Would it fit with my Battery being where it is?? Theres only a small gap between Battery and filter.

[Fawbs]

Should be ok if we need to take some measurements just bring your car down to the base. He can make anything out of carbon, if he needs it for a day or so i will happily lend you my car but like i said this is some way off at the moment.

[Fawbs]

Ok i havent been out to the car to take pictures of the route i used but i can tell you what i need if i remember correctly, you need:

http://cgi.ebay.co.uk/25mm-WELDING-CABLE-T...id=p3286.c0.m14 25mm2 cable in red and black up to you i got like 5 or 6 metres of the stuff each

http://cgi.ebay.co.uk/DURITE-MEGA-FUSE-HOL...id=p3286.c0.m14 x2 fuse holders

http://cgi.ebay.co.uk/WELDING-CABLE-RE-USA...id=p3286.c0.m14 something like 10 of theres

http://cgi.ebay.co.uk/DURITE-100AMP-BUS-BA...id=p3286.c0.m14 bus bar

http://cgi.ebay.co.uk/DURITE-150amp-MEGA-F...id=p3286.c0.m14 150amp fuse

http://cgi.ebay.co.uk/DURITE-MEGA-TYPE-FUS...id=p3286.c0.m14 125amp fuse

http://cgi.ebay.co.uk/ALLOY-BATTERY-TRAY-B...id=p3286.c0.m14 Battery box or tray

I think thats everything maybe some cable wrap too forgot what its called the stuff i got. Just need to figure out how to secure Battery box or tray someone suggested to me laying a silicone based seal down and putting some anchor nuts or something in it so i can bolt the box down.

[paulgtt]

Should be ok if we need to take some measurements just bring your car down to the base. He can make anything out of carbon, if he needs it for a day or so i will happily lend you my car but like i said this is some way off at the moment.

Yeah thats cool mate, I suppose if he can make one to fit yours I should be able to fiddle around with it slightly to fit mine. No rush though fella, just give us a yell when somethings in the pipeline.

[GT4 James]

Hi again guys, hope your all well, just got back from Holland myself hence no replies but had a great holiday B) Here ive managed to get hold of a "relief" valve for motor, have fitted and am running MASSIVE boost now Ive had it fitted both ways round just incase i fitted it back to from or something and have had it wound all way in and all the way out near enough and it just wants to run silly psi....any ideas wat that could be? Ive opened up RV just to make sure there is the old ball and spring inside and there is...will grab some pictures tomorrow i think.....one day she will boost properly

[paulgtt]

What is she boosting too mate??

Have you disabled the TVSV and if so how have you done it??

Glad you enjoyed your holiday too ;)

[GT4 James]

What is she boosting too mate??

Have you disabled the TVSV and if so how have you done it??

Glad you enjoyed your holiday too ;)

Hi paul nice one mate! Well she is spiking nearly 20psi and hitting fuel cut. tvsv is disabled and has been done by snipping hose between actuator and tvsv and blocking off both pipes.

[paulgtt]

Sounds to me as though the pipes aren't blocked off properely. The one from the engine block isn't really important but the one from the actuator is, it must be completely sealed or the pressure will seep out, bypassing the actuator and boost will go off the scale!!

If this isn't the cause it maybe a fault with the actuator itself, also what exhaust have you got and is it decatted??

[Fawbs]

With mine i cut some bolts up, stuck them in the pipes and put the clips around them, sealed up well, no issues.

[GT4 James]

Pipes are blocked off as you described with bolts and clips definitely a good seal, exhaust system is kakimoto middle to rear otherwise still got cat?? Has only happened since fitting this new relief valve, like i posted earlier i did have one working off my friends car which definitely was a relief valve ran 17psi fairly accurately and could be adjusted, then fitted "bleed" valve and ran fairly pants and now with new relief valve is boosting like mad.

[Fawbs]

You want my relief valve i have no more use for it as im gonna be getting a gt3076r. I'll see if i can find a picture of my set up

[Fawbs]

http://turborevs.org.uk/Manaul%20Boost%20C...20Turborevs.pdf that should help you, fitting instructions for my boost controller, pretty good