I have a 98 v70r with an engine that is starting to get a bit tired, and I've started to look at options for building an engine to replace this one once it dies. Planning on going with a 2.3 block (most likely sourcing one from a 99 R), and aiming for ~350 (very reliable) hp (I'm hoping to overbuild it so I won't need to worry as much abusing it).
I'm pretty clear on what needs to happen to make the engine strong enough, and have proper fueling and flow, however I'd appreciate some input on the turbo. I'd like to choose one where the boost threshold remains decently low while still having the capability of making 350hp at relatively safe boost pressure, or in other words trying to keep a balanced power band.
I've been made aware that getting a td04 hybrid built would be the easiest option, however my name is Garrett and I have come to the realization that I'd like to put a Garrett brand turbo on my car. Yeah it's a stupid reason, and I'm well aware I could get 350hp much easier and cheaper from a near stock 2.5 instead of spending a bunch of money building an engine, but I'm doing this mainly for my own enjoyment and to learn from so I'm choosing to ignore any common sense there.
From what I've read so far, some options that might work are:
GT2871R
GTX2867R GEN II
GT3071R
GTX3071R GEN II
GT3076R
From the very basic calculations I've tried to do, it seems like the GT2871R, GTX2867R GEN II, and GTX3071R GEN II are generally the closest to what I'm looking for, however any input would be greatly appreciated.
Here's the only relevant whiteblock/garrett turbo map I was able to find (from vast tuning):
Looks like the GT2871R is a decent fit, misses main island but still in the neighborhood.
I tried to extrapolate that data onto a map for the GTX2867R and got this:
Looks pretty similar, but hitting overall lower efficiency numbers.
So since I'm no expert, does anyone have a clue which out of these two might be the better fit? Is there any potential a 3071 or 3076 would work well or are those too big for what I'm looking for? Doing a basic map on those it looks like I'd be a lot closer to the surge line at low rpm, and not really taking advantage of their full boost capabilities.
On top of that, I'm pretty confused on what sort of A/R/turbine diameter/trim I should choose. If I go for a smaller A/R, is it OK as long as the wastegate is large enough that it can keep it at the proper corrected turbine flow at full boost?
Any advice is appreciated, TIA.
