nazarite

Hey Guys, wanted some extra eyes on this:

I've got a 99 NB1, 46k miles, completely stock with the exception of an NB2 header, and BP5A cam. To say I'm pretty disappointed is the understatement of the century. Here is the latest dyno.



Below is an overlay of my best runs with airbox open from day 1, completely stock, even before tune up, and today, as well as best baseline runs that were done 2 months ago the week I bought the car, before I even tuned it up. Essentially no difference. Something doesn't add up here. Uncorrected numbers say 9 hp gain, but it was also August in Georgia and 17 degrees warmer when I did the first runs vs. the runs after mods. I fully expect to hear "get a turbo," but why would I have 0 gains from those two mods, which should be among the best mods for an nb1 motor?





Any thoughts? I fully expect to hear "get a turbo," but why would I have 0 gains from those two mods, which should be among the best bang for the buck mods for an nb1 motor?

Efini~FC3S

iTrader: (4)

Your august runs have a correction factor of 1.05 and the new ones have 1.00?


You sure you're comparing apples to apples here?

Braineack

iTrader: (62)

n/a power mods are the biggest waste of money you can sink into a miata.

nazarite

You are correct. Two different days, two significantly different temps and humidity levels. Shouldn't SAE simply be accounting for those things, and gains show regardless? Uncorrected numbers showed a 9 whp increase, but a 17 degree difference in temp, and at least 6% difference in humidity.

I'm not disagreeing, I have my "fast" car and am really modding this for modding's sake. The header was free, cam cost me $230ish, so I'm not going that crazy here... That being said, I still hope for more than 0 gains.

concealer404

iTrader: (3)

You won't gain meaningful power on a Miata with a stock ecu, doubly so if you don't open up the motor.

I say this as someone who made 132.9779 or whatever whp on a Mustang dyno with my car, but my motor is probably a freak. Or the dyno was off. Or maybe i was wearing a special shirt that day.

Point is... Brain is largely right.

nazarite

Haha, I appreciate that. Special shirts ftw.

Thanks for the insight. I do plan to open the motor, if only to up compression by 1 or so. We'll see. I've got 93 by me, so hopefully with tuning I can at least notice a difference from the stock 87 tune. Most of the money will be spent on wheels and suspension shortly, just looking for any low-medium hanging fruit on the na front.

Thanks!

concealer404

iTrader: (3)

Doesn't exist, but you sure can spend a couple grand to net about 10whp if you're intent on doing it.

Example with where i'm at (Note: i never baselined my car):
BP5A ecu
Racing Beat header
Hytech midpipe/"muffler"
Skunk2 throttle body
K&N Typhoon intake

I'm still on the VICS manifold. I would expect additional gains on my car by installing a 5A intake cam (which sat on my shelf for 2 years, so naturally Monk and i installed it in my DD yesterday instead of the race car), and the Skunk2 intake manifold that just dropped. I'm also leaving a lot on the table by running the 5A ecu. The car continually drowns in fuel.

The dyno chart actually spit out 128whp/108ftlbs, but wasn't scaled for RPM properly. So... 133whp on a Mustang. And it feels like it.

My advice is to maybe throw a Megasquirt at it, but focus on making it handling in the meantime. Then decide how you want to make power. BPs are trash.

nazarite

You outlined my most likely route. Full bolt ons, bp5a cam, and a tune, maybe high compression pistons or a head shave after that. No need to make it super fast, just fun.

My first real money will be spent here shortly on quality coils, wheels and tires. Again, just surprised to see 0 difference, assuming SAE corrections can be trusted.

Savington

iTrader: (31)

SAE themselves say accuracy better than 2% is difficult at best. With a 5% CF and two months of time between the tests, you're seeing your gains fall into the noise.

sixshooter

iTrader: (12)

How about the fact that adding better breathing to an engine with a stock ECU that can't do much about it just makes it run leaner? WOT is open loop. All the fuel the stock map is set to give is what you get. Make it breathe better and you get... nothing much more. Get a tunable ECU and you may get a few horsepeters more.

vitamin j

iTrader: (5)

Can't get extra power without more fuel. Fail aids like fuel pressure regulator or JDM ECU will do a little but you could probably get 10hp with a Megasquirt. Everyone already knows this though so you will likely just get some heavy wheels and fail to spin them.

Goingnowherefast

iTrader: (1)

1. Listen to Savington about dyno numbers.
2. I honestly would not sink a lot of money into the NA build plans you're thinking of.
3. A well designed DIY intake and Racing Beat header are the best bang for buck.
4. You should get a Megasquirt 3 to tune the car (tune on E85 for more power).

Everything else is marginal and you're better off going turbo or Rotrex or just plain spending the money on tires, suspension, aero or track days.

pdexta

iTrader: (17)

I was tempted to go there earlier, but I feel like I'm always posting about the magic cornjuice. I seem to remember some posts from 949 about some really impressive n/a E85 gains with just a megasquirt, like something around 15whp? I don't think I documented anything, but I remember seeing some good gains going to E85 pre-turbo.

nazarite

Thanks Savington, appreciate the response to my question without questioning my lack of turbo.

This was what I was looking for. Nowhere have I seen "add a header and cam on stock ecu, see no power."

I think this is a burn, reads like a Geico add. I plan on finding the heaviest 6ULs I can. Thanks!

1. Done
2. Will sink as little as possible into it, got the Miata to tinker so I don't mind spending money on a hobby knowing full well the expected return, have a modded Evo for straight line go fast
3. Cool
4. Will do,

And most of my Miata budget will be spent doing exactly that, thanks for the advice!

Coming from the Speed 3 and Evo world, I'm incredibly well versed in the corn juice. It's just not at any gas station close enough to my house to be practical so I'll have to settle for 93. Thanks!

Think we can close this thread ha, thanks for all the replies everyone.