Stiggy Pop
In the cool kids club
- Joined
- Feb 27, 2011
- Location
- Granville, MA
I am planning on replacing the HX35 I have been running on my 242 for a few years; with the intent of getting something a little more 'modern' and responsive. The Holset was not overly laggy on my setup, providing full boost of ~23psi around 3900rpm, but I would like to net better transient response and hopefully pull the powerband up a couple hundred rpm.
- I would like the headroom for a ~400whp 2.3l redblock, ~7k rpm redline (will adjust based on new valvetrain and turbo), without the turbo being on the 'outer edge' of it's efficiency.
- The motor has a balanced and hardened crank, 158mm rods, 96.5mm Wiseco's, o-ringed block, fresh and healthy with under 5k miles on the machine work.
- The head is an RSI stage 2 with good port and chamber work, 48/40mm valves, a custom valvetrain and RSI stage 3 cam (.490" lift).
- Divided tube header with a t3 flange, Nathan intake manifold etc etc. It's got everything it needs to flow as well as I can set it up.
Below are the contenders I've been reading about (exhaustively), ordered from least-to-most likely.
GTX3576R Gen 2
Pros
- It's big. Lots of headroom.
- Good performer for the size.
- T3 divided EWG housings available
Cons
- I think it's too big. It made it's way onto the list after shopping the 3076 and seeing data which suggests the 3576 performs almost as well down low and much better up top.
GTX3076R Gen 2
Pros
- More headroom than a 3071, a little more reasonably sized than the 35.
- T3 divided EWG housings available
Cons
- mismatched wheel sizes. 3071 seems to do basically as much on paper while being a better performer down low.
- advise seems to be that if you NEED a 3076 you should buy a 3576
EFR7670
Pros
- seems to slot in somewhere between the 3076 and 3576
- A lot of headroom with better response than the 3576
- TiAl wheel for good transient response
- 'newer' tech than the GTX series
Cons
- I think it might be too big
- I'd have to pay MORE for an SXE style compressor housing which would be my preference
- No T3 housings. Would have to get a T4 housing and reflange the header (cost, complication) or run an adapter (just don't love that idea)
G25-660
Pros
- Latest and greatest tech
- Pretty amazing response and performance for the size
Cons
- I can't get it with a housing that works. The only T4 housings I can find are IWG. If they had a t3 housing for these I'd buy one.
- I think the most expensive turbo on this list
EFR7163
Pros
- More responsive than a 3071, same or better ceiling
- fresher in the life cycle than the GTX
Cons
- no t3 housing. T4 housing is IWG only from what I can find
- upcharge for the slimmed down SXE housing
GTX3071r Gen 2
Pros
- seems to be the best suited Garrett for 450bhp out of 2.3l
- EWG T3 divided housings available in nice NiResist material "drop on" for current manifold
- 4" inlet will plumb easily to existing intake setup
- better wheel sizing than the 3076
Cons
- A little long in the tooth, in some ways replaced by the G25-660. That's basically my con right now, just what it is NOT which is G series or EFR tech.
- I have to figure out how to cleanly go from a 2" outlet to a 3" intercooler (applies to the list at large)
- it's just as expensive as all of these.
So right now I could almost pull the trigger on a 3071. I can get the nice NiResist housing in .83 or 1.01 A/R. Thoughts there?
- I would like the headroom for a ~400whp 2.3l redblock, ~7k rpm redline (will adjust based on new valvetrain and turbo), without the turbo being on the 'outer edge' of it's efficiency.
- The motor has a balanced and hardened crank, 158mm rods, 96.5mm Wiseco's, o-ringed block, fresh and healthy with under 5k miles on the machine work.
- The head is an RSI stage 2 with good port and chamber work, 48/40mm valves, a custom valvetrain and RSI stage 3 cam (.490" lift).
- Divided tube header with a t3 flange, Nathan intake manifold etc etc. It's got everything it needs to flow as well as I can set it up.
Below are the contenders I've been reading about (exhaustively), ordered from least-to-most likely.
GTX3576R Gen 2
Pros
- It's big. Lots of headroom.
- Good performer for the size.
- T3 divided EWG housings available
Cons
- I think it's too big. It made it's way onto the list after shopping the 3076 and seeing data which suggests the 3576 performs almost as well down low and much better up top.
GTX3076R Gen 2
Pros
- More headroom than a 3071, a little more reasonably sized than the 35.
- T3 divided EWG housings available
Cons
- mismatched wheel sizes. 3071 seems to do basically as much on paper while being a better performer down low.
- advise seems to be that if you NEED a 3076 you should buy a 3576
EFR7670
Pros
- seems to slot in somewhere between the 3076 and 3576
- A lot of headroom with better response than the 3576
- TiAl wheel for good transient response
- 'newer' tech than the GTX series
Cons
- I think it might be too big
- I'd have to pay MORE for an SXE style compressor housing which would be my preference
- No T3 housings. Would have to get a T4 housing and reflange the header (cost, complication) or run an adapter (just don't love that idea)
G25-660
Pros
- Latest and greatest tech
- Pretty amazing response and performance for the size
Cons
- I can't get it with a housing that works. The only T4 housings I can find are IWG. If they had a t3 housing for these I'd buy one.
- I think the most expensive turbo on this list
EFR7163
Pros
- More responsive than a 3071, same or better ceiling
- fresher in the life cycle than the GTX
Cons
- no t3 housing. T4 housing is IWG only from what I can find
- upcharge for the slimmed down SXE housing
GTX3071r Gen 2
Pros
- seems to be the best suited Garrett for 450bhp out of 2.3l
- EWG T3 divided housings available in nice NiResist material "drop on" for current manifold
- 4" inlet will plumb easily to existing intake setup
- better wheel sizing than the 3076
Cons
- A little long in the tooth, in some ways replaced by the G25-660. That's basically my con right now, just what it is NOT which is G series or EFR tech.
- I have to figure out how to cleanly go from a 2" outlet to a 3" intercooler (applies to the list at large)
- it's just as expensive as all of these.
So right now I could almost pull the trigger on a 3071. I can get the nice NiResist housing in .83 or 1.01 A/R. Thoughts there?
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