if all these BOT cost alots, might consider swap to turbo engine...slightly expensive but less headache....

TD05 is too big for your engine, boost spooling so late is not a fun thing at all, pick up will be tremendous slow, for your setup, all I can say is if you are on the highway then your boost will provide the best power. But for normal town drive, I would seriously reconmend you to downgrade the turbine size or change to a ball bearing turbine, for low budget can go for subaru turbine.

For more reliability in order for 1 bar boost that you are achieving now, a good set of low compression piston is a must bro. Strong internals for the long run bro...if not at 1 bar, your engine will very easy to pecah...

hehe been there done that for my 4G93 BOT

This post has been edited by SuperVelocity: Jul 10 2012, 10:52 AM

I don't know a lot about turbo, but my guess is because you have more aggresive cams (compared to standard anyway) and combined that with a big turbo, you've effectively pushed your torque and power to the higher RPM range.

You know, the more aggresive cams you have, the less torque you have in the low RPM range and combined that with a bigger turbo which, this is what you get.

Just my guess...

td05 spool around 4-5k n td04 spool around 3k.
bigger turbo tend to save fuel when cruising around 110-140 because it not spooling.if cc nt big enauf it will lag.the flow not strong enauf to push the turbine.housing inlet to big.
smaller turbo already start spooling around 110.fc like crazy.town drive should be nice but nt good for hway.housing inlet smaller.
so choose your turbo wisely.
btw campro bot...u kinda crazy.even u got strong internal ur block can sustain in long run?

This post has been edited by Kaninbu: Jul 13 2012, 10:22 AM

alot of limitation I must say, therefore full monitoring system is a must and always drive within the limitation and not overboost it, turbo tends to get boost spike and thats the dangerous thing that will kill the engine...

turbo spools all the time. On wide open throttle from start, TD05 will build pressure around 5k above. TD04 2-3k above but puff out of breath around 5k. That's where your boost will drop slightly or equalize with atmospheric pressure.

Big or small turbo has minimal to do with FC. Tuning, way of driving and setup yes. If you use big turbo, but never build up pressure, your engine will consume petrol like average NA. If you boost, depends on the tuning, stoichiometry, efficiency of the power transferred and Power to weight ratio is perfect, your FC will be good also. You can hit 5k rpm with vacuum. Controlled entirely by your foot. There are alot of ways to reduce lag slightly. A bit too lazy to elaborate.

Your turbo will spool to build up pressure when its either wide open throttle or throttle opening is big enough to flow into the intake manifold. don't get confused. Pressure in the intake manifold may not be the same as your intake piping. All is regulated by, your BOV, your Throttle body and your wastegate.

Yes. Running up to 1 bar with stock internal for S4PH. No problem. Only problem is traffic jam and you cannot use all the pawa. Monitoring is essential if your setup is half complete. A complete setup will have proper ventilation ensuring the engine bay does overheat, a good management, injectors, fuel pump ensures adequate supply of fuel and injection volume, Good & correct tuning with proper ignition timing, and good boost regulater. E.g boost controller or wastegates.

Cant agree more than such good explantion for bro Vervain.

That depends what you plan on running with the TD04. I have used TD04H on 1.8 all the way to 7000 rpm holding 1.2 bar. My current setup runs at 1.0 all way to 7k rpm on 2.0 engine without dropping boost. I have tested the TD04 running out of breath at 1.4 bar at max rpm when my vacuum hose to the actuator valve popped out on my old 1.8 GSR. Good thing it ran out of breath there otherwise I might not have an engine left.

The only thing regulates the boost pressure and that is the wastegate/actuator valve together with the solenoid connected to the ECU. The pressure is always measured after the throttle body. The BOV plays no part in the regulation of pressure as it is there to play the role of a release valve when the throttle body shuts to prevent pressure building up in the intake pipe. It does not ever play the role of pressure regulation. It's more of a safety valve than a regulator valve. The throttle body does not regulate turbo pressure either.

ok.. here's my take. Most of the points I think i can concur.

Wastegate/Actuator = Controls peak boost. Pressure activated. agreed. Wastegate relies on loaded spring, so peak boost control can change mechanically with spring selection. Actuator has fixed max boost. Change whole actuator only because it's not meant to be dismantle.

Solenoid = yes if the ECU/Management have Boost control capability. If not, most older gen cars/simple setup runs without it. There are simple mechanical boost controller, but it just regulates the boost, allowing higher boost tolerance for low boost wastegates/actuators.

BOV = yes safety valve. Activated when there's vacuum in the intake manifold. Depressurize the air pressure before the throttle body. Agreed on relief valve.

Throttle body = yes, does not regulate turbo pressure, but you do have control on boost via pedal? It does regulate the pressure into the intake manifold and controls the engine rpm & indirectly controls the amount of exhaust fumes out which spins the turbo? if not the boost meter will only register one value, which is the peak boost regardless of which throttle position you put.

I've never pop my vacuum hose. But I've ever pop open the sillicon hose to the intake manifold. If worse case scenario where your actuator doesn't work, your throttle body and your foot will be the last saviour if it does react fast. You either cause some compressor surge or pop the pipeline for the intake system. I trust the Throttle body valve is strong in resisting such force. I've never driven a turbo setup with solenoid/ boost controller mechanism, and would appreciate if you can share more experience on boost controller. But I've driven a turbo car without wastegate.

Just some of my understanding. feel free to correct.

The throttle body does not directly regulate boost pressure. Meaning you can keep your foot at 50% throttle, the boost will climb and then once you reach a fixed speed, the boost will drop. So the throttle body is no longer considered as the component incharge of regulating the boost. Taking your foot off the gas is not considered as regulating the boost pressure. That's more like regulating the whole engine operation and not just the boost pressure alone.

Most OEM turbine with actuators valves run with solenoid, even on my old 1994 GSR. That's an 18 year old car. The manufacturers use the solenoid setup to activate limp home mode to cut the boost by allowing the full pressure of the boost to reach the actuator which is set to open at a lower level (usually half of full boost). The solenoid then acts like a boost controller in normal running mode to bleed the pressure away so that the turbine will maintain the OEM boost pressure. Think of it as a poor man's boost controller but you can't change the settings unless you mess around with the ECU. On most OEM cars, if you remove the solenoid and pipe the hose direct from intake manifold to actuator, you will only get half boost since the spring settings are made to open at a lower pressure.

Majority of the owners then remove the solenoid and replace with an aftermarket boost controller. That is why you don't see much solenoid/actuator setup because most have been replaced with aftermarket boost controllers. You want to easily see an OEM solenoid/actuator setup? Just pop the hood of Preve CFE and you can see it right next to the actuator valve. Most manufacturers put the solenoid as far from the turbine as possible so that it does not get cooked but not Proton. You will also find it on almost all OEM turbo engines but you will have to trace the vacuum hose since the solenoid place quite far from the turbine actuator.

This post has been edited by sleepwalker: Jul 17 2012, 12:50 AM

Well we can't deny the fact that engine does effect the turbo operation. 50% throttle body yes. But if the throttle position is lower say 20%, I doubt there will be any pressure build up unless there's very low load. I think this debate would be endless.

Yup I know Preve CFE has a solenoid on the borg warner turbo housing. That too kept me wondering on the reliability. Yup regarding on solenoid function I do agree. But I think it's also because the internal wastegate actuator's spring is not as strong as those external. Slight pressure may open the door results in efficiency drop.

The turbocharger on Preve is off the shelf part from BorgWarner, even used by Audi and VW. I think nothing wrong with the solenoid location since BorgWarner EFR series also got the solenoid near the compressor housing same as turbo from Proton. :-)

It's not about the debate. We are talking about your understanding of the word regulation and not about the workings of the engine. You regulate engine function with the throttle body and regulate the turbine pressure with the acutator/wastegate. You do not control the pressure of the turbine by using the throttle body.

20% throttle on 4th/5th gear I can bring my boost to almost maximum on load while at the same time 20% throttle on 1st gear hardly gets the boost to 50%. That is what I meant by turbine boost regulation is controlled by actuator/solenoid which is electronically controlled from the ECU taking engine load as a factor. Here the opening of the throttle body no longer controls the boost. The more load I put into my engine, the more boost I get from the same throttle body opening. That is why I kept saying that you can't consider the throttle body as part of the turbine boost regulation. The throttle body is more on controlling the engine as a whole.

Yes, once you take the foot of the gas, throttle body shuts and boost drops but we don't consider that as boost regulation. There is no DIRECT correlation between boost and throttle body except when the throttle body is shut. That just shuts down engine operation to 'idling' mode or deceleration mode. Hardly considered as boost regulation.

LoL, I think this discussion will go endless. Personal view, I still think in general TPS does give you the power to control the boost in some way until it reaches your peak boost whereby the Actuator does its job. Probably the word regulation is not applicable but by controlling the TPS, you may control the boost coming into the intake manifold if the pressure difference is big. Obviously as you've mentioned, load and engine operation does come in sight in generating pressure, but indirectly it still relies on TPS. (engine operation, exhaust gas etc...)

You hit 1 bar on high speed, then decides to cruise slower, instead of lifting up to shut off the throttle body, you slowly reduce the tps % to reduce the amount of air pressure coming in to the intake chamber. Pressure before throttle body will increase at this point till the BOV relieves or the turbine is relieve by the actuator & slows down the pressure building process. At the moment where the pressure differential is there, your TPS does limit the air coming into the intake manifold, thus registers a lower pressure. No doubt if the load increases, tps % constant, the turbo still building up pressure, pressure before throttle body increase, the pressure coming into the engine will increase because the amount of air & velocity increases. But it does give you the power of controlling the pressure by further reducing the tps. We all know if there's pressure above atmospheric pressure, the engine operation will increase until its overcome by the load.

Just my point of view. Hope you won't hammer me hard again

td05 on campro ? then you should change your engine to 4g63