Need Some Advice on New Turbo Build
 

Hey guys, I'm a new member here (actually I just now made an account to post but I lurk here occasionally), and I have some questions about a new build that I've been planning. I have a 1997 NA with a fully built bottom end, bored to 84mm and want to go the turbo route. I am interested in a drift build and already have the suspension and rigidity issue somewhat figured out. Although, I have a couple questions on power and was wondering if anyone could chip in their two cents. Firstly, I have been looking at the 6758 TS for my power goals of around 400-450, although I take it that there are no manifolds available for the NA that are TS and T4, as the 6758 TS only comes in T4 variant. Will a manifold have to be custom made? Or is there one available? Secondly, is the 6758 TS even worth the response rate, or should I go with something else? There are at least a thousand other questions on my mind but these are the most pressing, I appreciate any help. Thanks!

Hello, I’m also currently piecing together a turbo Miata and have been tirelessly doing research so I’m fresh on the topic of building a turbo FOR DRIFTING and have been drifting with the lonestar drift crowd in Texas for several years. My engine is a stock and abused 95’ 1.8L, but I plan on building a newer 1.8L in the future so I’m building the turbo system to eventually fit on a built engine. I’ve already committed to my turbo assembly with a Garrett GTX2860R with a T51R mod on a flying Miata turbo manifold. I’ve looked into the 6258 vs the 6758 spooling to power capabilities and the 6258 is capable of making 400hp while spooling around 200rpms quicker depending on your set up. In my opinion and for my driving style, 200-400rpm is significant. A 6258 set up with only 300hp is effectively just as quick as 6758 with 400hp, but that only applies for drifting. You can also look into custom building your intercooler piping to be half as long, which should close that spool time gap between the 6758 and the 6258, if you desire to run your turbo at lower rpms at your goal of 400 - 450hp which of course would make for a more reliable turbo set up.

Wait, you are looking at the Twin Scroll turbos? No off the shelf manifolds exist to my knowledge, and you're over-complicating an easy part of the system.

FYI I run a "regular" 6758 and see 14psi by 3500 and full boost (16 at the moment) by 3800 when starting a pull around 2500rpms in 4th gear (6speed, so not 1:1 gear) and am super impressed with the response. Great turbo! Kraken makes a great manifold

400-450 is going to need e85 in my experience or some other octane booster, I was knock limited to 305whp (conservative dyno) on my 6758 using straight 93 octane. I haven't seen anyone make near 400 on pump with a BP -- I would love someone to correct me though