Discussion GTD1756VRK VS Hybrid CR170 52MM

[WWJSWD]

For the CJAA, here's my thought process. In my opinion, low displacement diesel engines work best and are safer at higher RPM when under high engine loads. The GTD1756VRK spools extremely quickly, and will produce peak boost much lower in the RPM band than a CR170, and even more so than a CR170 with a larger compressor wheel. So while the CR170 hybrid is more sluggish to spool, it forces the driver to operate the engine at higher RPM. This in-turn, is easier on the engine thrust bearings, dual-mass flywheel, and clutch.

So, slightly more lag = superior/safer? What are your thoughts?

 

[lemoncurd]

exactly, which is why i went with a larger turbo. the GTB2260. but i had a larger compressor wheel fitted, so it flows more

it still spools nicely down low and is VERY driveable, but all the bigger power is up high where it wont break ****

 

[smelly621]

Yes it's generally agreed that huge torque at low rpms is more stressful on the bottom end and rest of the drivetrain but there is more to it than just x psi of boost at x rpm = laggy safe or preferred.

The torque limit, requested boost, air mass flow rate and fueling in your tuning all play a bigger role in my opinion when it comes to breaking stuff down low. Then sure, at a certain point egts get high with a smaller turbine and smaller compressor wheel. Surge at lower daily driven rpms must be considered though when trying to tune/selecting a larger compressor wheel turbo.

I was under the impression that a cr170 was slightly smaller in terms of turbine and compressor sizes compared to a gtd1756 and thus would be at peak performance at a slightly lower rpm range. Both have excellent transient performance though and will have you at or near the limit of the stock head airflow.

 

[lemoncurd]

Surge at lower daily driven rpms must be considered though when trying to tune/selecting a larger compressor wheel turbo

only really surges when you try to get on it when below 2k RPM and in high gear... which happens with a normal 2260

otherwise it drives around just fine

 

[Rogerbslee]

For the CJAA, here's my thought process. In my opinion, low displacement diesel engines work best and are safer at higher RPM when under high engine loads. The GTD1756VRK spools extremely quickly, and will produce peak boost much lower in the RPM band than a CR170, and even more so than a CR170 with a larger compressor wheel. So while the CR170 hybrid is more sluggish to spool, it forces the driver to operate the engine at higher RPM. This in-turn, is easier on the engine thrust bearings, dual-mass flywheel, and clutch.

So, slightly more lag = superior/safer? What are your thoughts?

Does the Gtd1756vrk require a lot of expensive
supporting hardware compared to the hybrid options?

 

[WWJSWD]

Does the Gtd1756vrk require a lot of expensive
supporting hardware compared to the hybrid options?

There are CR170 52mm hybrid turbos that have been adapted to the US spec exhaust manifold and US spec compressor housing. Meaning it is truly a bolt on upgrade, when tuned will get you comfortably past 200HP and 350FTlb of torque. The GTD1756 has a unique exhaust housing with a longer snout on the turbo outlet, meaning you’ll need a custom downpipe, you’ll also need to drill and tap an EGT probe port into the exhaust manifold, the compressor housing doesn’t have a low pressure EGR port and is a larger diameter so you’ll need to adapt a euro spec CR170 intake pipe or purchase a GTB spec intake pipe from darkside. Compressor outlet is different as well, but should be a 45 degree silicon pipe… so a lot more work, but, a better turbo all around.

 

[Rogerbslee]

ewww we da L

There are CR170 52mm hybrid turbos that have been adapted to the US spec exhaust manifold and US spec compressor housing. Meaning it is truly a bolt on upgrade, when tuned will get you comfortably past 200HP and 350FTlb of torque. The GTD1756 has a unique exhaust housing with a longer snout on the turbo outlet, meaning you’ll need a custom downpipe, you’ll also need to drill and tap an EGT probe port into the exhaust manifold, the compressor housing doesn’t have a low pressure EGR port and is a larger diameter so you’ll need to adapt a euro spec CR170 intake pipe or purchase a GTB spec intake pipe from darkside. Compressor outlet is different as well, but should be a 45 degree silicon pipe… so a lot more work, but, a better turbo all around.

Thanks great information!
I’ve been looking for an upgrade over the stock turbo that doesn’t sacrifice anything in spool up and low down torque. Seems all the hybrid options lose something at the bottom end but from your description the GTD1756vrk should not. Sounds like some extensive modifications required but if my local shop can handle it I think it’s the way to go.
I’m assuming I would need a custom tune?
Any recommendation on a vendor for the GTD?

 

[Escape.idiocracy]

Performancetdi.com based out of Canada. Good price and reasonable shipping on hybrid 170’s

I have really enjoyed the hybrid 170- I commute roughly 200 miles a day. In town the lag is perfect doesn’t try and peel the asphalt up from a stop unless you really want it to. Good power up top. Definitely do the 4bar map, 2200 fuel rail, open exhaust, and there is definitely a reasonable difference with an arm/Afe dry drop in filter (flame away…)

This turbo definitely turns the Cjaa into a go-kart.