Braineack

iTrader: (62)

this.

if you want 140-150hp, buy a 1.8 VVT.



the SR20 T25 is not a fast spooling turbo on a 1.6L (really, nothing is)


here's the SR20 T25 on a 1.8L vs a 1.6l:





even something small like a GT2552 cant spool well on a 1.6L miata:




the cam profile prevents it.


1.6L turbo setups are ******* stupid. the 1.6L motor is complete dogshit. :P

williams805

iTrader: (2)

I'd say go for it if you can fab all your own parts. Boost threshold will be low and vertically no lag in any normal street driving rpm range. However the fact that your asking instead of posting pics of your homemade manifold with the turbo having off tells me this my not be the way for you. It will end up costing you more to pay others to do your fab work than it would to buy quality used, known to work parts.... FM mani, down pipe, and 2554.

Also you will change the way the engine wants to run. It will probably start to sign off by about 5k and really be falling hard by 6. This means you've basically lowered your usable rpm by about 1000 rpm. You could probably tune a boost controller keep the boost up a bit in the upper rpms, but you will most likely be over spinning the turbo... So reliability becomes an issue.

Of course this is speculation as I've not seen the compressor map for your turbo in question. However I have seen and driven a K03 from a late 90's 1.8t Audi/VW on a 1.8 Miata. The car was a great street car at 5psi. But it wanted to be short shifted due to falling boost (and of course torque) past 6k. Which was fine because there was plenty more lower rpm torque to be found in the next gear. Kind of like a little 4 cylinder muscle car. 5 psi by 1800 rpm dropping to 4 at about 6k. Torque was plenty useable. It was to the right of the compressor map by about 6500rpm.

So if you want to do it and can fab your own parts, go for it. But know there will be limitations right out of the box. A used fm mani and a 2554 is a lot more suited to this engine though and will probably cost about the same.

sparkybean

Why oh why didnt i put a 1.8 in before deciding to DIY a manifold. **** sake

SoLoOne

Hey, I resemble that remark! My 92 Miata w/ TD-04, HUGE intercooler, and Bipes APU work great -- no trick ECU or programmable stuff, this is just hard-wired and self-tuned. Boost goes 5-10PSI from ~3000 RPM to 7500 (red-line). Performance is acceptable, though we always want more. A 2007 BMW M3 got me but just barely. Spent $1,000 on the car (came turbo'd) and about $700 in fixing suspension and various other problems not relating to the engine.

Not sure what else I can do, supposedly I should be able to get another 4PSI out of this thing. I bought it running 5 PSI originally, tweaked it and now @ 10PSI. Drive it till it "pops" is my plan, then maybe upgrade. My setup is a band-aid style, but if it works, don't **** with it right?

"It's not what you have, it's how you use it"

18psi

iTrader: (76)

Sorry to pee in your cheerios, but:
07 m3 runs low 13's at 109mph
You're not even getting close to that trap speed in a janky band aid 1.6 miata.
Like, not even in the same zip code in a race. He'd have to be short shifting the car or flat out just messing with you to lose.

patsmx5

iTrader: (16)

Yeah this happens...... Can confirm.....

DNA54

If you wanna know what can you do to an engine with a too small turbo, just look at the first post in my build thread: https://www.miataturbo.net/diy-turbo...p-miata-79849/

tiny turbo in most cases means tiny wastegate port, and so creep. Lots of. And creep to 18 psi at 3000 rpm isn't cool, it simply makes a big hole in the hottest piston
buy a 2554, it's common, cheap and it spool very fast

ryansmoneypit

iTrader: (6)

I couldn't imagine having to wait until 5k to get 10 psi. Good gawd. At 20 psi, I rarely rev past 5 k.

SoLoOne

This was just good fun on the street with a friend. And I lost, not by much. I hit 1/4 mile at about 95-97 mph. I have oversized rear tires and was double clutching. Maybe I had the better lane that day. That's why we race in cars and not on paper.

Edit: It is an 04 M3, not an 07.

90civichhb

iTrader: (5)

Member since 2011 and these are your first two posts

18psi

iTrader: (76)

Even still, 95-97 vs 105-107 is a 10mph difference
Unless he wasn't racing or trying, its not even close

Theres a difference between a race and ricer fly by

SoLoOne

Look for advice and find ridicule. Nice post. Wonder why I don't participate here. BTW: 2011 is when I bought this "janky" Miata.

18psi

iTrader: (76)

The problem is that you're a ricer.
You think that just because you beat the driver of that car for whatever reason, that it's ok to go around and say that your 1.6 band aid miata can walk a m3.

that's nonsense.

we all know here what a band aid 1.6 miata runs and what a properly driven m3 runs. many here even have both cars.

I'll go race a bugatti veyron tomorrow in my son's big wheel, and come back and tell you guys "It's not what you have, it's how you use it"

herp derp

buying a 1.6 is strike 1. putting band aids on it is strike 2. talking about beating cars that trap 10mph more is strike 3.
3 strikes and your argument is invalid. have a nice day

Savington

iTrader: (31)

I want to sig this so badly

SoLoOne

You read way more into the message than what I wrote. Again, wonder why I bother here. I bought the car as a toy. Never said I could walk an M3. I just shared an experience while looking for advice on where to go next. Hope the ridicule helps others, sure doesn't help to tell people everything they did wrong. But whatever gets you off.

Braineack

iTrader: (62)

That's not really true

18psi

iTrader: (76)

don't be so salty. its not that serious

SoLoOne

Can you elaborate on this? Interested.

SoLoOne

Yeah I can use a decent dose of calm the F down, I am good with what I have so far for the $$$. I don't have lots of money or much time and space to work on my toy. I just like hauling *** as quickly as I can.

[eating (salty) humble pie] 😋. Lol.

Braineack

iTrader: (62)

there's no reason you cant run a small turbo at low boost.