Technical Here Here! Turbo from a T Jet on a 1.2?? A little technical discussion to pass time:)

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Technical Here Here! Turbo from a T Jet on a 1.2?? A little technical discussion to pass time:)

Basicly on top of the actuator regulating the exhaust gases you've got an electronic valve on the intake side regulating the amount of vacuum acting on the actuator? Like a regulator for the regulator? :LOL:

I don't think that would work.. If your producing boost and its being measured in the inlet manifold how can the vacuum be taken from there, its full of Boost, so there most be a separate vacuum pump like on the JTD. :confused:
 
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So could the vacuum be taken from the intake side, pre-turbo?

Not sure, I wouldn't think so. Not enough of a vacuum there, if there was air would come rushing in through the airfilter and then no more vacuum.

Got to be a pump I think ..

How does the JTD pump work?

Mechanical or electric?

Electric would be good, easy to fit in a 1.2
 
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In fact this is where I'm confused, I thought the actuator was there to reduce boost and even it once the manifold reached a certain psi, so would it not rely on an increasing manifold pressure to work properly? I've been reading the GP threads and they seem to explain it pretty well but can't remember the thread atm. But it was something along the lines of the manifold pressure creates the vacuum which acts on the actuator spring which will begin to move once the intake reaches a certain psi (determined by the spring stiffness)?? :s
 
I thinK post 30 explained a wastegated turbo, the actuator is fed with boost pressure from the compressor housing, this relieves exhaust gas if pressure too high, have a look on google something like DIY turbo porting, most are opening the relief hole to let out more gas to exhaust.the actuator rod is just fitted to a disc covering a hole. Low boost hole covered, high boost hole uncovered.
No vac on wastegated turbo usually.
 
I see looking on eBay at actuators that some turbo's now have electric actuators. Look to be a dear thing to fix when they go wrong??
 
That video's pretty cool :)

But this has rather opened up more questions than answered :/

I thought it would be a case of connecting the actuator to the manifold or pre-turbo but now it seems I wouldn't need the actuator at all? Earlier on I read somewhere that some people weld up the actuator so it doesn't move? Is this a good thing? Keeps the turbo at low boost all the time?

You are good at explaining, but a diagram of some sort would be great right now :) The little hose fitting on the actuator spring housing - what connects to it and where does the other end go?
 
the actuator is fed with boost pressure from the compressor housing

Is that what the nozzle on the compressor housing (just below/right of the compressor outlet) is for in this picture? And so would the hose just go from that nozzle straight onto the other nozzle on the actuator spring housing?

tjet turbo ya bitch.jpg

Can also see the send/return oil lines, in fact the return (or vice-versa) is in another picture, I got this off an eBay listing. Could I supply oilto the turbo through a dedicated oil supply?
 
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Would this "turbo conversion" work better on the 1.4 "95BHP" model as thats probably closer to the T-jet punto engine?

If so would be cool to see it done then maybe have a crack at it on my 1.4 :D

maybe after i finish the coupe to stilo engine transplant project on my other stilo :p
 
Think of the turbo as a boost generating device, and then think of the wastegate as the turbos over pressure relief valve.
I'd say a small bore hose goes from that small hosetail on compressor outlet straight to actuator hosetail.
When people fit bleed valves to turbos it's usually fitted in this line, and just bleeds an amound of boost away from actuator fooling it to build higher boost.
A welded up wastegate will just keep boosting regardless of pressure, dragsters maybe looking for 30,40,50,60 psi.only regulation will be energy fed into exhaust from fuelling.
Had a quick look on you tube. Search turbochargers-explained its 3 min 46secs . It's not me.
 
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Thank you Sussexa I think I've got it now (y)

With regards the bleed valve, would it not be better to have an adjusteable actuater, with a stiffer spring/ adjust the rod for more initial boost? Though I think this way it would need an ecu remap to work effectively.

Would this "turbo conversion" work better on the 1.4 "95BHP" model as thats probably closer to the T-jet punto engine?

The 1.4 has a higher compression ratio at 11.2:1, the 1.2 is 10.6:1 and the Bravo TJet 120 is 9.8:1 so the 1.2 is much closer in terms of the compression ratio required. Though you could get a decomp gasket for it no problem I'm sure, just I got a 1.2 ;)

Well the turbo and manifold will bolt onto the cylinder head ok and if you've got space on the 1.4 then you can use the TJet intercooler and plumbing, you should probably use a bigger throttle body as well, just not sure how to get oil to the turbo :/

maybe after i finish the coupe to stilo engine transplant project on my other stilo

Ohhh you got a thread for that?? Would love to see that! :D

Sussexa, how can I sort out getting the oil to and from the turbo? I know where the send/returns are on the turbo but from where will I get the oil form?? And how can I increase engine cooling?
 
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You can buy fittings for oil feed and return and hose. Drain needs to be unrestricted ie large bore, and you can plumb into top side of sump above oil level line. Feed to turbo is from a tapped thread in an oil gallery in the block, not sure where you'd pick up from, you need around 6 bar I think maybe pick up off a oil filter sandwich plate as you'd need one for oil cooler anyway?
Engine cooling you won't know till running your rad n pump etc may cope with extra heat?
You need to quiz someone who's done a conversion realy, did you read that link to cinq turbo conversion, I'm just guessing really.
 
OK did a bit of reading on the oil coolers and they make sense to me now. Should have mentioned long ago that I am a noob when it comes to turbos :LOL: But the oil cooler makes sense now and how you fit in a sandwich plate to allow the fitment of oil lines for the turbo. Question is can I get a sandwich plate custom made for my car as obviosly there won't be one off the shelf for me ;)

Just to make sure I've got this right: Oil send- sandwich plate, Oil return- tapped thread into sump. Correct?
 
if i told you that the turbo used on cinqs and seis for the 1242 engine iirc was one straight out of a 1.7 astra diesel and as far as i know is the one Van Aarken used for the 1108/1242 turbo conversions would that save your headache on trying to get your head round VGT?

the advantage of using a non-VGT is that you pretty much only have to worry about FAR tables and would do away with desired and actual boost etc etc.
 
if i told you that the turbo used on cinqs and seis for the 1242 engine iirc was one straight out of a 1.7 astra diesel and as far as i know is the one Van Aarken used for the 1108/1242 turbo conversions would that save your headache on trying to get your head round VGT?

the advantage of using a non-VGT is that you pretty much only have to worry about FAR tables and would do away with desired and actual boost etc etc.

I'd read about that before from some other threads long ago but just didn't think much of it :rolleyes: I know they're rapid anyway :p

Does the turbo manifold bolt striaght on to the 1242 head do you know?

And what are FAR tables?
 
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