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Tuning turbo time!

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Tuning turbo time!

Whats the a/r of the gt15 turbine housing? If its still .35 or something like that then theres not much benefit from going over .45 with the compressor.

Also watercooled cores are an absolute waste of time, money and effort. You will NEVER see the benefits unless you like to switch off immediately after a hard drive, and even then watercooling will do little to help that. All you are doing is putting more heat into the water system, when what you really need is a decent oil cooler!

I know im picking faults here, but hopefully its constructive criticism :)
 
Munkul said:
Also watercooled cores are an absolute waste of time, money and effort. You will NEVER see the benefits unless you like to switch off immediately after a hard drive, and even then watercooling will do little to help that. All you are doing is putting more heat into the water system, when what you really need is a decent oil cooler!
Click to expand...

Are you saying that water cooling the turbo is waste of time in general in "our" case? Mine has water inlet/outlet and I was struggling recently with supplying it coolant in a "cheap" way (that is basically without rebuilding the whole system, I hooked up the turbo instead of the TB), and so far only trouble - air in the system and coolant boiling in the turbo after switching the ignition off. Currently the pipes are disconnected, but I am thinking about dumping the whole thing....
 
the problem with using the throttle body feed is that it is used to keep air out of the system. thats why its high up and goes to the top of the coolant tank. so by running it thru the turbo it goes to the lowest point of the engine meaning air cant escape. fitting one of them cheap swirl pots before the line will solve the problem.

not sure of the a/r of the compressor. but its all bits ive got so worth a try :)
 
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Munkul said:
Also watercooled cores are an absolute waste of time, money and effort. You will NEVER see the benefits unless you like to switch off immediately after a hard drive, and even then watercooling will do little to help that. All you are doing is putting more heat into the water system, when what you really need is a decent oil cooler!

I know im picking faults here, but hopefully its constructive criticism :)
Click to expand...

I was on my phone when i first replied and battery was going (n)

i really dont think watercooling is a waste of time. I dont know of any production petrol cars with a turbo that is not watercooled. there must very good reasons for them to do so (think of the money they could save by not!)
also it preserves oil life (ill still change the oil just as much it will just work better)

but i guess it comes down to opinion. id just like to have the extra cooling. (y)
 
it gets unwanted are out of the system :)
basically its a tube with the coolant in at the topside and out at the bottom side.
then right at the top a small hose is connected that runs back to the coolant tank (above water level)

the inlet and outlet ports are positioned to make the coolant swirl which pulls any small air bubbles together making them float up and out the small tube.

i know that some standard cars have them. out fiats basic one is it the TB cooling hose.
notice its the highest point on the system. where it connects to the heater hose it has a large block of rubber. this is like an open space for air to leave the water stream.

I have a clear hose that bypasses the throttle body and you can see a trail of air bubbles in it.
 
haha, aye most performance cars come with watercooled turbos, most people agree its mainly because it allows the oil to cool more slowly when you switch off, so it doesnt coke as bad if the turbo temp is still really high. Basically, for all the joe bloggs out there who dont give a crap about their turbos and switch off immediately after a hard run.


....which are then blocked off by tuners as its just dumping heat back into the coolant which could be going into the oil (more efficient means of heat transfer) and its just another thing to go wrong.
Look at it this way - oil is great for cooling because it can go up to 110 degrees without being dangerous (although still ideally below 100) which water cannot do without loosing a lot of pressured steam.

Look at a lot of high performance cars - do they still keep watercooling jackets? In a lot of cases no. Holset turbos are mostly just oil cooled and they are amazing turbos, stronger than the equivalent garretts and in spite of being journal bearing, they still rival Garrett ball bearing turbos for spool-up and are more efficient for their boost level.

If you have a decent size oil cooler and a good radiator, then there is no reason why the oil cant deal with ALL of the turbo heat. And with regular 6k oil changes it wont have a difference on engine life.

I know what you are saying - it is a good thing in most respects, but its definitely not worth the hassle of money and time to acheive on your car. You will never EVER be able to say to someone "there i have just proved the benefits of my watercooled turbo core".
 
Thanks munkel :)
Well i have a watercooled core and the air/oil so ive got choices.
Id like watercooled for the main reason that when I do events the engine is toasting after. have up to 25mins before the next run and so im stuck with leaving the car running for ages
the last one i did it was running pretty much all day... used hell of a lot of fuel and not exactly brilliant for the engine. but ill see :)

anyway...
new engine is in and it sounds sweeeeet. had a couple of issues with the crank sensor, it was 5mm off (never thought about it even knowing the engine used to run aircon) had to make a adaptor plate.

first test drive showed a problem. very slow gain and boost and only getting 0.2 bar.
turbo has shagged itself sounded like a empty can full of nails!
can a headgasket blowing between two cylinders kill a turbo? I did nurse it home about 2miles, stayed off boost but the car gunshot out the exhaust a good few times (guess this could do some damage)
I knew the turbo was looking bad during when i took the head off as the shaft had more play then usual (hence why i started looking at hybrids to tweak my spare turbo before i fit it)
 
fitted new turbo. all is good now.

Stripped the old one and found something interesting.

the turbo was what came with the black cinq and was told it was brand new.
it did look new. no play in the shaft and all shiny and no rust.
but i stripped it just and noticed that the compressor wheel and even the nut had no "cuts" in it that all turbos have when they are balanced!!!! could the turbo of been a reconditioned unit with chines parts fitted?

the new turbo sounds different to, the old one always made a loud woooshing noise (people always commented on it saying it sounded good... i thought it sounded like a road sweeper :))
the new turbo is MUCH quieter.

the old turbo is beyond repair. the shaft is extremely worn!
 
i stripped down a 1.2 today (60) and it had those main end caps on it, i was guessing a very late 60 as it had the 866 cam

strange markings on them like a rotary engine and the caps where marked with

a rectangle
2
C - id guess it stood for centre
4
5

was surprised by it

Ash
 
right... hybrid is in.
had a change of plan. the gt1752 looked way way to big... it was mahoosive. so after building it i took it apart and fitted a 45 size compessor but also machined out the exhaust housing to fit a larger and by the look of it more modern turbine. the turbine has less blades with more of a cup shape its quite a bit lighter and whiter so might be ciramic?

and the results... cars lag is nearly non exsitant... might even have less lag. power is unreal, spin both wheels in 3rd at about 30mph without any effort. and will pull like a train all the way to 7500rpm limiter. (actually forgot to change up because there was no noticable drop in power at high rpms) turbo is silent! and feels so smooth on boost unlike the old turbo. well chuffed...
 
not much to say... machined it out till the turbine fitted in the housing :) i had the original housing to copy from to get the shape inside the same-ish
turbo was from a rover iirc
0.7-8 bar.
no boost creep (machined the waste gate hole out so its about 2mm smaller then the flap)
do get a spike when coming onto boost but I think its cause the wastegate feed on the compressor housing is restricted (I unscrewed the barb and there was only a tiny hole behind it) and there is about 6foot of hosing for the boost controller.
 
found a photo i took very bad quality tho. sadly I never thought to take any of just the housing because I was in a rush :rolleyes:

Top (painted blue) is the standard astra crap (tiny!)
Bottom right is the 52size compressor and is a monstor... in my eyes it looks to big.
next to it on the left is the one im using. housing is a tad bigger then the astra one and the hose connections are the same size but the bore is about 5mm bigger on the output and lot bigger on the in.
the compressor wheel is closer in size to the 52's wheel then the astra one

left of that is my machined out turbine housing.

above that are the turbines.
left: new one
Right: astra

IMG_20101025_155320.jpg
 
the turbine and compressor are from the same turbo so I marked the shaft/compressor/nut and lined it all back up. so shouldnt be out of balance :)

Thats what I felt in mine. boost has always come on at silly low rpms but seemed to loose its balls at higher rpms (could easily feel it taper away and it sounded not as sweet) was never sure if it was intake or exhaust restriction, expected intake hence why i matched all ports. removed any restriction i seen and looked into bigger compressors.

must of got lucky and hit a sweet spot :)

never went water cooled either :p ... my engine bay has enough hoses and wires as it is
 
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