I was so confused for a moment until I realized it was measuring in newton-meters instead of ft-lbs. That is 222 in freedom units for any of you other Americans.

Twinscroll worth it?
 

I was baffled by the dyno with no way to zoom in because mobile app.

Yeah its in Newton Meters. But as you said its 222 freedoms at the wheels at 4286rpm, and 212whp@5157rpm

Its a virtualdyno run, but al the runs i did over a few weeks where very similair.

But i want something with more power and better spool. altough the spool of this turbo is pretty good.

you're not gonna get much better spool than that even with a t25
more power? sure, tons of options, at the expense of spool

that's a solid street powerband, I'd enjoy it

Gee fellows, is it time for a 2560 for the low end fun, plus something else for top end?

It can't prove that difficult. Can it?

corky

with variable turbine and compressor geometry you can have both...

The answer to both questions is: Borgwarner EFR 6258

I've no experience with the Borg turbo, but hopefully that will end soon.

Strong doubts remain that it will prove much different.

corky

Since that whole what happens in 5th gear thing was brought up like last page, my 6758 makes 2psi if you floor it in 5th at 45mph. That 5speed 4.10 gearing. Of course as always the bigger deal is that it drives like its just a bigger engine when you're over ~4k and into instaboost land. But its still no slouch below that. The EFR twin scroll housings are a bit odd, they seem to have sized them in an attempt to maintain the same boost threshold but flow better up top. which is different from how they're normally used.

A 6278 & a 6758. 45 in 5th is about 2200? And offers 2 psi. The 2860 matches that pretty easy, and the 2560 typically hits 4 at 2000 revs.

A VATN Aerocharger could be adjusted to make 10 psi at 1000, but it was undriveable. Best setting seemed like about 4 to 5 psi at 2k was good, but it was reluctant to make 200 rwhp.

Perhaps a 2860 and a VATN.............. I think I'll pass.

corky

I'm contemplating an he351. VGT holset. Can potentially be controlled with MS3. My buddy picked one up for $150. I think it might be sized a little big for a Miata. Pretty sure it has a hx35 exhaust housing.

Try it for science. Someone here questioned once upon a time the long term reliability of the vatn in a gasoline application, iirc. Nobody here has tried it to my knowledge. These turbos are very common on machines I sell nowadays.

I was very impressed with that one guy with an aerocharger a while ago making 200tq by like 2k and response so fast it was ridiculous. But his power plumetted up top and IIRC that turbo was unreliable

I know of exactly one variable vane gasoline turbo application. The turbos are readily available...for ~$5200/ea

Its a stupid heavy thing. At least 25 lbs. Will be interesting to see if I can build a manifold strong enough.
<br />I'm going to help him with running the vgt controller by megasquirt then search for my own. I've seen a dyno of a supra with his turbo. 20psi by like 2500rpm.

Biggest issue is they want to work at like 25+psi they aren't efficient below that. But I don't have a car that wants to work at 25+psi.

Twinscroll worth it?
 

Then it might be a poor choice? How many reasons does it take to become a bad idea?

Since when does bad idea = not fun? :) I'm going to play with some cheap turbos, just need to build an engine first.
<br />HX-30 if first on my list. Followed by the he351.

aidan - the new and improved faefae

Not sure if compliment or insult... :)