gt17...
Turbo Mini Forums

after the smoke had cleared (and this took a while ), i had to solve my smoking stevensons rocket .so i decided either rings /pistons,guides,turbo,magic.
i discounted magic ,and went to turbo ,but its fine ,then looked at guides ,seem fine but stuck some new top secret guide seals on ,oh ok ,not secret at all just joining in the secret stuff fashion they are off god knows what but have a metal body brown in coluor and are tighter on the valve ,prob off a vw or vauxhall..
anyrdup
i also wondered whether the 2 head gasket exp was the prob ,so have abandoned that @@ bodge@@ and back to one gasket and 8.5 to 1.the gaskets had slipped 3 mm out of alignment which could have allowed the oil to run from oil hole to cyl1.
another prob i found was that looking into the cyl i could see a pool of golden liquid on top of the dish ,assumung no one had peed into my plug holes i deduced this was fuel so looks like somehow my carb is leaking fuel into the cyl at rest ...???very strange ,so the upshot of this is ,
to get something good out of disaster , i m converting the engine to a gt17 turbo from the garrett gt range,would anybody be interested in a sort of running comentary and pics of this ? or not ?
regards robert.
oh ps ,any suggestions why fuel would be collecting in the cyl at rest gratefully recieved ,apart from fuel pressure !!

ok scrub that the golden fluid seems to be oil just found a drip on the end of the exhaust and it was golden and deff oil !!

Edited by robert on 21st Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Indeed, keep us updated.....

oky doky heres some pics of what iv achieved since monday afternoon,these show the turbo on the manifold and the 2 turbos side by side ,, i went into witney yesy and got the braided pipe made up for the oil feel which is diff thread ,and 2 water feeds ,they had no oil drain so ill make that . the nice job today is the down pipe, id made one for the t3 ,and im a bit loath to cut it incase the whole exp is a duffer ,but i may do ,just crawling around underneath try to see by how much and whether its easier to make another ...its all twin wall stainless mercedes cat pipe ...not easy to saw!

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

4 bolt peter round inlet, and iv hunted for a cm but no luck so far ,its a gt1752 if you find one let me know !!im sizing based on a interpolation of the avaliable maps and experience on the blade design etc, i think the only instinctive drawback i can see is the turbine may be a bit small for high power ....time will tell!1 anyrdup my clutch wont take a lot .lol

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Robert,

Have you removed the compressor housing and measured the compressor wheel diameters and counted the blades?
This might help us 'home in' on a compressor that is something like close (identical?)

The numbers from the Saab units don't tie up with the 'normal' compressors from my past searches Peter. That's why i asked for the compressor dims.
There are (i understand) three outputs of this engine aswell - I'm guessing that might also mean three different turbochargers?

yes dave ,as i was saying to you at avon ,i think theres the 150 170 and 195 bhp ,

i may be wrong on the 195 i think it uses the 41mm wheel i found on another 17 iv got ,which would do as an upgrade if needed,

but i think the 170 and 150 both use the 1752 ,
its got a 38.. 52mm cw and 38.2 44 mm tw
it seems to fall between the 2052 and the 2059 .
and looking at the blade design ,and the fact they are used on iveco trucks at over a bar ,im ''deducing'' a reasonably high map centre ,and a pk bhp flow limit of around 220 bhp probably quite similar to the wheel in your turbo but prob more blades and a touch smaller
regards robert
oh well done for that peter , i hadnt seen that one .thank a lot .

Edited by robert on 21st Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I have a gt 17, not fitted yet, i think mines from a saab 95, i've been unable to find any maps either.

well ,would you believe it ,one saw cut and it fits !!
hers the down pipe and the piece to weld in ,and the car its all happening to .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

what do you mean ,with saab turbos doesn't respond to "normal compressor",
does your comp hsg is using the 0.33 a/r?
do you know the distance between the end of the blades and the start of the curve on them?
I thik you have a 55 trim comp , at which pressure ratio will you use it?

bit of an idea of the oil drain clearance ,looks like a straight drain and hose into the block should do it purloined a straight drain off a ihi rhb6 ,that fits well so just need a hose.
down pipe is now welded up and just needs cleaning and painting ...

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

yes robert that's the info I needed ,
I join your though on the higher a/r .
comparing with other maps (I didn't have this one but a tad smaller and bigger), it seem that it'll flow other 20lb, but I'm not sure it'll like the 10 psi's , being a high flow turbo it will like boost and revs :), you know when the pshiiii change of note and then you know it's really in his space. so sort that gearbox and clutch troubles (I didn't have enough money to buy a sccr gearbox,after two major gears failure I tried innocenti gears (pre a+,in an A+ casing, and minispares large bearing first motionshaft transformation, it made good results at low cost.
regards
fabrice

heres some more progress ,finished off the downpipe ,and the fittings for the turbo ,the comp fitting on the pipe gives me a choice of length to keep it all away from the hot side






whoops thumbnails !

oh the pipe is 51 to 54 mm id ,and is made of 8 pieces @.

Edited by robert on 25th Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

ot ? no peter its a cone shaped fitting ,it uses a flared pipe end
regards robert.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

I think Peter was on the same line as my thinking - Is the Turbo to manifold bolt pattern T3 or T2?

dave peter was asking bout the outlet flange ... the turbo inlet to manifold one seems to be the same as a t25/t2 .
oh and thanks for the encouragement peter, i was wondering if there was really any interest.. id hate to be the pub bore

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

peter ,the bolt patten is the same on both outlets ,3 bolts on a triangle,the t2 /t25 flnge input bolt holes are about 5mm inside the t3 bolt holes all around . the 17 im using actually has a bigger comp wheel than a lot of the gt20's (ive nmow found that it was also usee on thee 185 bhp saab!!)
,but a smaller turbine ,im thinking of going external w gate too if i can find a way to fit it .so the turbine wont choke ,id really like to see a 2.5 inch down pipe from the turbo ,and splitting the ex flow to an ext w/gate would alleviate the load on the 52 mm down pipe iv got ,that really isnt big enough .
incedentaly peter , i hope you dont mind me saying ,but that centre head pipe seems very acute in angle ,does the head still flow ok with that on ?

Edited by robert on 26th Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

peter are you sure thats not a 41.5 mm ind wheel on that map?that makes it 3mm bigger than mine eff. is mega ,but i wonder if thats a bigger and heavier turbine and comp than yuo need for best response ?oops just noticed you said full race , and saw yuor plotting airflow for about 240 bhp .so maybe yuo do need that combo ,id look at the lower sizes too though

Edited by robert on 26th Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

no sweat peter ,its all interesting , i def think that of the 2 yuoll have more fun with the 20 ,ill have a look at the options ,if yuo look at the 40 trim t3 it deff has more flow lower down than the 20 so you could mAYBE TRADE THAT flow FOR THE 45 OR 50 TRIM T3 wHEELS LIKE THE RS ESCoRT ONE(45) ,THEN WITH THE .25 A/R TO BRING IT IN . oops caps key .on the other hand , if yuo need sort of 200 up bhp and a small turbine ,hey ,gt1752 !!

Edited by robert on 26th Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

well the garrett view is its safe to sat 10 bhp per pound of air ... i tend to the 10 to 12 bhp per pnd with a good ic . ,but using the garret system youd want about 19 lb of air on the baseline .if your using a lot of duration for rpm ,then yuoll find that even with the a/r down low itll not really kick in till the cam does ,depending on the usual technicalities of flow reversion engineering , coatings, pipe insulation ,turbine crossover pressure engineering etc . so i wuoldnt worry bout mapping for much under the cam reversion swap event.
i dont think that lag would be noticably increased with a 45 wheel on the t3 ,but i may be wrong wierd things happen ,! till you build it sometimes you cant tell ,thats what makes it all so fascinating .im very intersted to see what this 17 does ,its a shame the only dyno readout i have for it is one with a less ported head and 3.5 psi but with the same cam and springs.and with a 9.3 :1 cr , so its hard to get a direct comparison , for steady state bhp it may not be hugely diff , on the other hand if its one of those near 80% eff turbos like the 22 thingumy ,that would be a big step in bhp i think.time will tell ..

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

heres a bit more
the pipe is the one to go to the ic inlet pipe from the compressor ,and the wastegate actuator has to be mounted as shown ,so i have to make a wee bracket to suit ,work for fri cos im employed tomorrow !!

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

id have thuogt 200 bhp per litre would be very feasable ,but id have thuoght yuod be hitting 8k rpm on a race engine . its your .050 opening times that really matter on a roller cos the ramps are down in duration ,good luck with it peter.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

ok ,back on topic ,,,
if i want to do ext wastegate then i need to mig weld on the cast manifold ....does anyone know what its made of ?? or has anybidy(leaving this mispelling in cos it reminded me of the policeman in allo allo ..) experience with welding onto it ?
thanks
robert.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

190! seriously, good luck with that. Using some formula younks ago, I calculated that 165 would be possible with a 998. And if I get anywhere near this I'll be more than happy. Still stuck around the 140 mark.

New 'hybrid' turbo for next year me thinks.

To be honest our engine is great, but really on the limits of driveability at the moment, it's just brutal. I don't want anymore power untill we can get it to handle properly.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk