Boost problem... Or not a problem?

[Kevorkian]

About a week ago I bought an ST185 and like all new cars, it takes a little while to figure out the best way to lick their nipples and flick their pink bits.. I've managed to work out so far that whilst running stock, their exhaust system utterly sucks @55 and doesn't want to put out much of what goes in, in a hurry.

One thing that I actually thought was a problem but I was later told that it's to do with the thermostat is the fact that until the car is warm I get basically NO boost out of it what so ever. A friend of mine who used to have an ST185 has told me that the computer limits boost in 1st and 2nd gear, but also in every gear until the thermostat hits a certain temperature. This does indeed seem to be the case and once the car is nice and warm boy does it get up and boogie

Basically I just want to verify this, I guess you would call it, "Temperature boost limiting???" or something of the like. Thanks guys

[flygt4]

yes. its called the turbo vsv , or vacuum switching valve... basically to stop you thrashing the balls off it when its cold. the annoying thing is it also works when its too warm , such as when you've been sitting in traffic too long. do a serach of the tech area on turbo vsv to find out how to disable it. its just a simple hose

[mr pad]

Yeah thats normal.

Boost + Cold engine = Death to 3sgte

[Kevorkian]

Well at least I am not going crazy then

When I was told about it I actually thought it was a pretty good idea because I know how many problems people have with the ST185's. Hopefully mine will last a while.... Cause I never thrash it ... *COUGH**BuLL5H1T!!!!*COUGH*

[peas]

I thought that it was good idea when I learned of it. I did wonder why it was a little sluggish when I first bought mine. I avoid boost til it has warmed up anyway... almost religiously. I have a fan on the intercooler and the radiator fan running full time which keeps air moving through the engine bay and seems to help. I havent experienced "nanny mode" due to heat in ages!

[flygt4]

mine was particularly bad at limiting boost in traffic. i ended up disabling the turbo vsv , gained a couple psi boost , and just made sure i didnt get stuck into it til was warmed up

[Kevorkian]

Hrm, thats pretty interesting.. How difficult is it to rig the fan to run all the time, and also is the fan you're using on the interwarmer anything specially designed to be used on coolers, or is it just like, a radiator fan thats cable tied to your cooler?

[Malcolm]

to make the radiator fans run all the time, unplug the aircon temp sensor (it plugs into one of the aircon hardpipes, just where it meets the firewall, in the back passenger side corner of the engine bay). For the intercooler fan you need a pretty small one (in diameter and thickness). SPAL and Davies Craig both do slimline fans in various diameters that can be made to fit.

[Kevorkian]

thanks bro I think I might wait until I get those things happening before I kill the VSV just to be on the safe side.

It's interesting to read on here all the different problems that people have with their ST185's.. like the boost problem, well, "feature" they have, and the crunchy second gear.. It is kind of annoying not being able to have the full amount of boost all the time because of that VSV.

The other annoying thing I can think of is the fact that they don't come with a stock BOV, which sucks because I can't just whack a new one on in place of the stock one. I really love the car, and the way it drives.. It shall become a long term project I think. I just hope I dont kill it before it turns into something special

[Malcolm]

you can just make the VSV stay open all the time, although the ECU also retards timing when it gets hot which reduces power.
To make the VSV stay open, thus giving you full boost all the time, all you have to do is cut the VSV wire before it enters the ECU and run it to ground. The solenoid is powered 12v----VSV----ECU switch----earth so if you run it straight to earth it will stay open. The other thing you can do is run it through a switch to give you high/low boost modes, which I did on my gt4. You can also replace the stock VSV with an aircon VSV which gives you bleed adjustment so you have an adjustable high mode (this is what I will do on my mr2 when I get round to it).
I would definitely suggest looking for a solution to the stock IC's problems, be it a fan, water to air, or front mount.

[Kevorkian]

Yeh, from what I have heard the stock interwarmer sucks.. or more or less doesn't suck...

Hrmm... Is a vacuum cleaner that really sucked, a good deal?

I wish I could wake up tommorro and have 250KW @ the wheels... Mmmmm Oh, and a new gbox

[Malcolm]

the intercooler isn't that bad, it's just not good for stuff like drag racing (because it heat soaks while you're waiting to run) or dyno testing (because they can't simulate normal airflow through it). For track work it would be quite good, and the incredibly short intake path makes for awesome boost response (especially with the ceramic turbo).

[FoRsaKeN]

Does keeping the Radiator fan going all teh time decrease the power outage of teh engine??? as in, doesnt it add to the strain, like when the Air Con is on??????

[Kevorkian]

I dont think it would affect power output because unlike the the radiator fan which just runs off straight power, the air conditioning compressor chews fuel and power from the engine in order to run.

[matt dunn]

Does keeping the Radiator fan going all teh time decrease the power outage of teh engine??? as in, doesnt it add to the strain, like when the Air Con is on??????

It will make the alternator draw a bit more of the engine but it will be such a small amount that even an accurate dyno would struggle to measure the difference.

Running the fan all the time will wear the fan out though.

Matt

[Kevorkian]

yeh I was told by a mate who did a 4g63t conversion on a front wheel drive australian delivered lancer that I shouldnt bother putting the fan to spin all the time because if it does get hot under the hood then the fan will come on anyways. I guess thats fair enough. I'm still a bit cautious to disconnect the VSV. I'll see what happens. I think I would rather do some work to the car first before I go tinkering for minor power increases

[peas]

Just unplug the thermo fan swith at the base of the radiator (drivers side from memory)... this will have the fan run all the time. The Davies Craig 10" fan sits perfectly on the intercooler, the flanges on the shroud sit in under the mesh frame. All you need to do is gring the central moulding down a bit to allow clearance to the underside of the scoop. I no longer have air con either, wasn't working properly anyway so out it came.

[Kevorkian]

Laugh, Air con out = stage one weight reduction
stage two would be no floor mats, rofl...
and you dont REALLY need those fog lamps, so that could be stage three

[peas]

If its not going then why bother having it? It didnt weigh much, but there is a truck load of room in there now and they arent the lightest car in the world so anything out has to be a step in the right direction... well maybe a stumble. I will be keeping floor mats and most definitely the fog lights... Im sick of DUMBF#@K Auckland drivers somehow not seeing me and dinging up my car!!

Wouldn't the point of having the fan on all the time be to not have the engine bay get hot enough for it to have to turn on though??

[matt dunn]

Wouldn't the point of having the fan on all the time be to not have the engine bay get hot enough for it to have to turn on though??

So you are going to run the fan all the time and draw air through the radiator to heat thye air up and then draw it into the engine bay?

So you are drawing hot air into the engine bay to keep the engine bay cold?