GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
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GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
I have a standard Garrett GT 15 turbo giving 90bhp on my AHU engine. I have read lots of threads about making a hybrid turbo but rarely from a GT 15, here's one example I found.
http://www.kermatdi.com/servlet/-strse-428/Turbo/Detail" onclick="window.open(this.href);return false;
a bolt on 15BHP extra giving 105BHP. is this just a modification to the compressor wheel or more than just that?
has anybody had a successful modification to a GT 15 Turbo using interchangeable parts from a K03 & K04 components?
http://www.kermatdi.com/servlet/-strse-428/Turbo/Detail" onclick="window.open(this.href);return false;
a bolt on 15BHP extra giving 105BHP. is this just a modification to the compressor wheel or more than just that?
has anybody had a successful modification to a GT 15 Turbo using interchangeable parts from a K03 & K04 components?
Why does everything I "want" - scrub that, need - cost so much?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
Are you E or M ? If E, then consider going to a VNT turbo, with suitable pump,injectors and ECU eg. off an AFN. That's a nearly bolt-on 110hp and nicer drivability. That's what's in my pickup.
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
syncroandy wrote:Are you E or M ? If E, then consider going to a VNT turbo, with suitable pump,injectors and ECU eg. off an AFN. That's a nearly bolt-on 110hp and nicer drivability. That's what's in my pickup.
MTDI Conversion
I think I've located an up graded bolt on turbo for the AHU engine non VNT I must add (Using Tim Shettle Turbo adaptors) which will give a maximum of 200BHP against the AHU Turbo giving a max of 150BHP. I'll hope to aim for 105BHP and my with my up graded injectors I hope a rough combined total estimate of 125BHP out of my AHU engine conversion.
although saying all this about BHP, the main interest should be geared towards torque.
i'll let you know when I know more about the new turbo and if it fits and some photo's
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
I've spoken to my engineer today who only has to alter the position of the actuator. This requires re-welding a cast aluminium bracket which I removed with a hacksaw and drilling a series of holes. I finished off the casting with a file, looked quite good.
I just hope the welding doesn't cause a hole to appear in the casting! hence the reason why I'm not doing it.
I've included the spec for the old and the new upgrade turbo for the 1.9L MTDI/ETDI if there are any bearded flat capped oily owners out there
old spec Max150BHP----------------New Spec Max200BHP
Compressor---------------------------Compressor
Inducer: 32.9 mm------------------- Inducer: 37.2 mm
Exducer: 43.9 mm-------------------Exducer: 48.0 mm
Trim: 56-------------------------------Trim: 60
A/R 0.33-------------------------------A/R 0.48
Turbine-------------------------------Turbine
Wheel: 42.2 mm--------------------Wheel: 41.2 mm
Trim: 58------------------------------Trim: 72
A/R: 0.35-----------------------------A/R: 0.35
Has anyone upgraded their 1.9L MTDI or ETDI with a bigger up-grade turbo using an actuator waste gate. I'd like to hear your results if you have.
I just hope the welding doesn't cause a hole to appear in the casting! hence the reason why I'm not doing it.
I've included the spec for the old and the new upgrade turbo for the 1.9L MTDI/ETDI if there are any bearded flat capped oily owners out there
old spec Max150BHP----------------New Spec Max200BHP
Compressor---------------------------Compressor
Inducer: 32.9 mm------------------- Inducer: 37.2 mm
Exducer: 43.9 mm-------------------Exducer: 48.0 mm
Trim: 56-------------------------------Trim: 60
A/R 0.33-------------------------------A/R 0.48
Turbine-------------------------------Turbine
Wheel: 42.2 mm--------------------Wheel: 41.2 mm
Trim: 58------------------------------Trim: 72
A/R: 0.35-----------------------------A/R: 0.35
Has anyone upgraded their 1.9L MTDI or ETDI with a bigger up-grade turbo using an actuator waste gate. I'd like to hear your results if you have.
Why does everything I "want" - scrub that, need - cost so much?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
I have a photo of the old turbo and new up graded turbo (old is on the left) this should give me 15BHP on top of the 90BHP but potentially may give me as much as 30BHP extra! I can't wait to find out the answer. will all my efforts just end up being a damp squib?
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Why does everything I "want" - scrub that, need - cost so much?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
VirginAtlantic wrote:
Has anyone upgraded their 1.9L ETDI with a bigger up-grade turbo using an actuator waste gate. I'd like to hear your results if you have.
the 90bhp actuator wastegate turbo can just about be forced to an honest 125bhp before it will be killed by unburnt fuel or the police pull you over for blocking out the sun with black smoke

thats why everyone keeps it for mild cheap tuning 100-120bhp but if anything above that is required a vnt is minimum because it needs to spool up much quicker
never worked on a mtdi but i imagine the problem with them would be that once you modify the wastegate (stronger spring,etc) then the fuelling would have to be sorted by trial and error, rolling road would be a must or at the very least someone who does mtdi all day every day
have you tried asking your local land rover owners, they do mtdi tuning big style
'88 1.9tdi karmann cheetah
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
hi busbuddy
Great minds think alike, yes for sure I'll definitely be running it on the rolling road. this is also necessary for the guarantee on the new up-graded injectors I've had fitted.
I do hope it doesn't smoke like the red arrows on display. I guess I will have to hope for the best and plan for the worst.
Great minds think alike, yes for sure I'll definitely be running it on the rolling road. this is also necessary for the guarantee on the new up-graded injectors I've had fitted.
I do hope it doesn't smoke like the red arrows on display. I guess I will have to hope for the best and plan for the worst.
Why does everything I "want" - scrub that, need - cost so much?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
the turbo is on the engine and now ready to go into the bus. waiting on the gearbox now so meanwhile I can prepare the engine bay and touch up the paint where necessary.






Why does everything I "want" - scrub that, need - cost so much?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
I have now fitted the exhaust and discovered the exhaust bracket doesn't line up with the crankcase holes. looks like it's a visit to an engineer for a small plate to be fabricated to extend the holes by 10mm. TDI Conversions keep asking for more ££££






Why does everything I "want" - scrub that, need - cost so much?
Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
A easy option in this case would be use a JX turbo or even the passat 1.6gtd unit, the problem you face is your turbo is still set up to work with ETDI I.e early spool up, as with all ECU controlled vehicles the big advantage is the fact you can dial timing in very accurately to suit boost pressure, this will prove much more difficult with MTDi so I am really not so sure having a hybrid turbo is the answer to more power, the real skill is how well your chosen fuel pump is set up to suit the running dynamics of a Direct injection VW inline 4
MV Engineering LTD
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01952 581818 mveservices@hotmail.co.uk
Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
And just to add, nice work by the way
MV Engineering LTD
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
Cheers mazz, haven't seen you since you had Matt in the back of your LT camper at Busfest. I bought the AAP box off Matt but opted for Aidan's upgrade in the end. The fuel pump is fine and with 11mm head should deliver the goods. I understand my turbo was in an ETDI set up but hopefully with a good rolling road session to set up the actuator i can get the maximum out of the engine. I also upgraded the nozzles so I've done everything I can do reasonably to get my desired result. The end of January I hope to have it all up and running ready for the new season almost 12months after I started this conversion! but if all fails back in with the JX turbo!
Why does everything I "want" - scrub that, need - cost so much?
Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
What is the fuel pump off ?
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Re: GT 15 - 90BHP Wastegate Turbo Hybrid for more BHP
Hi Mazz it's off a fiat, I also put someone onto you about a TDI plug and play loom this week. Hopefully you might hear from him. I think you've offered these looms before? regards
Why does everything I "want" - scrub that, need - cost so much?