Best power Gains

[Pure-Powder]

Building a 94 MX-3 Oval track car... Looking for the best mods for power gains in the high rpm range. We are running a 1.6L engine and an engine swap is not an option.

Any help would be great!

Thanks Dennis

[RS_OBD'oh_2]

the only way to get power out of the 1.6's would be forced induction. The extra heat on a circle track may be an issue for the cooling system tho.

[Pure-Powder]

Not allowed any turbos or such, I do see lots of talk about Miata Cam swap... I did a search and there is lots of talk but no one lists which year of Miata to get the cams from. also has anyone been able to switch out PCM, or reprogram so you can get rid of the rev limiter.

[Inodoro Pereyra]

Being that you can't use any forced induction, you will have to increase the volumetric efficiency of the engine, for the RPM range you're planning to run at.
So exhaust and intake design become really important. The bigger the exhaust tubes, and the shorter the exhaust runners (within reason), the higher down the RPM range your peak power will occur. It's important that all four runners are the same length, so you can tune your engine for the higher possible power delivery at your desired RPM range. Also, for an oval track I would use a 4 to 1 header, instead of a 4 to 2 to 1.
On the intake portion, you'd probably get a good HP increase by using ITBs, if you design the runners properly (right length, diameter and wall angle, to get the highest flow). Same with the camshafts: if you really want high HP gains, you will probably need a custom grind. A miata camshaft will only get you so far.
Finally, you can get an important power gain by increasing the compression ratio of the engine, to near the highest point your permitted fuel will allow. That and the proper ignition timing.

Unfortunately, many of these mods are trial and error, so you may be looking at a helluva bill...

[Pure-Powder]

Not lookin to spend the moon , just looking for as many mods as possible , that are cheap, now does anyone now twat year of Miata cams fit!

Thanks..

[Savin]

'90-93 miata with the B6 motor in it, after that it switches to the BP...

[Ryan]

B8 swap would be invisible to the uneducated eye. Still a 16v SOHC, just 1.8L. Same dimensions, just a few little details are different.

[Savin]

'94 in DOHC, Ryan. I think they might notice if he goes from dual cams to single cam, lol.

[Pure-Powder]

Yes plus the DOHC has more power

[Ryan]

No, B8 is SOHC.

It came in all the 4 door proteges that weren't BP.

They look exactly like B6ME's, just 1.8.

am I repeating myself?

[Savin]

Pure-Powder has a B6-DE not B6-ME. Therefore he has Dual overhead cams, not 1 single cam. If he swaps out a DOHC B6 for a SOHC B8, inspectors might notice.

And yes, you are repeating yourself, but I guess you didn't comprehend what I said originally.

[Ryan]

Ah, I see what you're saying.

Nothing looks like the B6DE.

Has it been verified that none of the 94's were SOHC? You could push that with the judges.

[Savin]

94 and up were definitely DOHC unless somewhere overseas it was different. The only motor that comes close to looking like the B6-DE is the 2nd gen BP with the valve cover that looks like the B6. But I think its still pretty easy to tell the difference.

I still think if Pure_Powder uses the miata B6 components (115hp) and tweaks things a bit (bore the cylinders, machine the head down, and port it) he could get around the same hp as the BP, and wouldn't be breaking any rules by changing out the motor.

[nos92mx3]

ive got a custom intake manifold for a b6de.
Let me know if youd be interested

[MazdaNut]

Make sure your Miata cams and pistons come from a manual trans car. The automatic has the same cams and low compression as the MX-3.

If you're looking for a cheap improvement vs an expensive optimization, check out my recent post regarding a header I've found. http://www.mx-3.com/phpBB3/viewtopic.php?f=3&t=75430