Savington

iTrader: (31)

Not enough to rely on.

falcon

iTrader: (13)

My motor makes power to 8k, kinda.. it will make more when my new intake manifold is on.

-Balanced bottom end + billet OPG + forged pistons/rods
-head work (porting), oversize SS valves (not a must but will help), solid lifters (must have if you plan to rev to 8k), cams and a better flowing intake manifold.

My motor starts choking at about 7800RPM right now but with my new gotPSI? intake manifold that will all change.

RotorNutFD3S

iTrader: (33)

I thought our OEM pistons were cast?

falcon

iTrader: (13)

Cast does not mean they are bad. I built a 600awhp gtr with cast pistons. It's all in the tune.

Savington

iTrader: (31)

The tune is damn important, but it's not all in the tune. You can't tune a Miata piston to withstand 900whp. You can tune it to withstand 300whp for a while, at least until you bend a rod. :P

messiahx

iTrader: (2)

Good thread. Answers a lot of my noobish questions.

You said ATI damper will not have benefits at stock motor "safe" power levels. I'm guessing if going through the expenses to build a motor it's one of those things you should just get?

Faeflora

iTrader: (2)

More info on VVT harmonic issue? I have stock VVT cams and rev to 8000RPM and soon will rev to 8500RPM.

fooger03

iTrader: (2)

IIRC: Stock VVT (01+) intake cam has been found to induce destructive harmonic oscillations somewhere between 7500 and 7600 RPMs. Fae, hold your rpms at about 7500 RPMs for a couple minutes, and let us know what happens!!

Messiah, your ATI damper questions should be answered in the original postings of this thread. The only benefit you'll see on an otherwise stock engine is a reduction in NVH near the top end.

Faeflora

iTrader: (2)

Riighht. I mean, have cams been exploding or something? And if so, whose cams? Do they like, make a special fat lady singing noise at that RPM? Generally, I am at 7500RPM for a tenth of a second.

Savington

iTrader: (31)

I answered this question the last time you asked it, too. It hammers out the intake valve seats.

1slowna

iTrader: (1)

i really like that you rated stock rods at 250tq, too many people rate them at 250whp and thats simply not correct. You should also note that with higher flowing tubular manifolds and larger turbos more power can be made on stock internal parts, less tq and less heat. Theres a big difference in what the engine goes through making 250whp on a begi s mani with a 2560 then a miata making 250whp on a custom mani with for instance a presicion 6057.

scottyd

Dibs on your head.

mx5autoxer

iTrader: (1)

So are there recipes for track ready, reliable cars at say 200, 250, 300 whp? Or is tune too variable to say, "Put on these parts and you can tack it all day without having to worry about breaking stuff"? I know this is pretty much completely different, but in the Supra community there is basically a parts list for achieving intervals of 100hp.

fooger03

iTrader: (2)

You could do what was suggested to make a streetable 200/250/300 hp, and then figure out what you need to do to take it from "streetable" to "trackable" Since this is a drivetrain thread, if I wanted to keep my answer on topic, I would list all of the drivetrain modifications required to make your miata "trackable". So I will do that:
o Oil Cooler

That's it. Your Miata engine is now racetrack ready. If you start becoming a faster racetrack driver, you will want to upgrade your exhaust/turbo hardware as well.

BogusSVO

iTrader: (1)

Bookmarked!

Orion ZyGarian

At what point would the factory 1.8 one on the oil filter not be enough? By "oil cooler" do you mean the factory one, or a fancy thermostat controlled oil to air?

fooger03

iTrader: (2)

Umm...the point at which you decide to go to a real life race track...
Going from anything else to lapping a race track can't be described as taking the cooling requirements from 90% to 100%. A much more accurate comparison would be to say that you're taking those requirements from 10% to 100%.

Cooling Stresses (percentages made up by me, but inspired by a true story):
Drag Racing: 2%
Highway cruising: 8%
Autocross: 6-10%
Your grandma on a race track: 70%
Fast driver on a race track: 112%

Fancy.

kieran

Unfortunately for you I believe he is refering to the OP

HHammerly

iTrader: (3)

I have a supercharged 90 that I built a couple of years ago and Just purchased a 99 sport w a hole on the block, I have a botom end core for the 99 and a complete VTT motor & Harness siting in my garage. The plan is to build a turbo like the one on the atached photo that i made for a friend's 1.6 , 10 - 12 PSI and rebuild a motor with scat roods , CP 9:1 pictons and build a turbo manifold and exhaust for a Brog Worner 179155 Turbo EFR-6258; 62c/58t, intercooler, injectors, megasquirt, coolant re-route, radiator
My question is, what engine makes the best starting point and final
Pakage? Is the VTT worth the extra work to install and wire in a 99 car?
Use for the car will be a fair weather driver, auto cross and ocational track day like my SC NA. http://s1084.photobucket.com/albums/...er_media_share
http://s1084.photobucket.com/albums/...er_media_share

Thanks for the advice.

fooger03

iTrader: (2)

The VVT will help you spool sooner, it will add more torque through nearly the entire RPM band.

The blocks are pretty much identical from 94 to 05, the heads make the difference. If you're going to rebuild it anyways, then there's no need to worry about compression from one year to the next. If you are capable and willing to tune the VVT head, you won't be sorry you did. Dive into that long block.