Turbo or Supercharger

[cwisenheimer]

Rob, It also sounds like your FM2 was the previous version if yours sat for 2 years. The whole kit has been redesigned since then. That said, the version I didn't fiddle with much at all was the earlier version (with no ECU).

[Rob®]

Yes, mine was the very early (first?) full FM2 kit with LINK ECU - the one that was supposedly a BEGi kit but rebadged/sold by FM. I know it has all been redesigned since that one, and I've heard MUCH better things about it, but I heard nothing but good about the one I had too...before I got it and started talking to others with it. What's the expression, "once bitten, twice shy"?

[TurboDuane]

Something to consider on a '90 model is the short crank nose, which is why I went with the BEGI4.2 kit (some called it the FM1) on my '90. I didn't want to add any unnecessary stress to the short crank nose. I was happy with the BEGI4.2 which is why I later purchased a '97 with the early FM2 with the Link (95-96) ODB1-2 workaround. Neither setup was perfect out of the box and both required some time to get them tuned for reliable power, so yes I had to tinker with them both. However once I got the maps and boost where I wanted them I had a lot of fun with both cars. Neither car stranded me, and I took them both on long journeys. The biggest problem that I had with the link was the electronic boost controller, that was a major PITA getting it to hold a set level of boost on the FM2 car.

I loved the power of the turbo and the thrill of the way the boost came in. However, for auto crossing it was always difficult to come out of the corners, as the power band was unpredictable, causing lots of over-steer.

If I ever modify my current '08 model I'd probably try out a Super Charger.

[Rob®]

Eh, the SNC issue is moot if you keep up with maintenance. I've put ~66k boosted miles on my SNC and it shows no sign of giving up. I have never ran less than 12psi from a GT28R, with the average being 16psi from the same turbo (I'd have to check my notes, but I would guess about 40k miles at 16psi from the GT28R). Once I put in rods, I went to a 2871 at 18psi for a bit, then went to an even bigger turbo for a while. And FWIW, when I put the rods in, I just replaced the rods - same bearings, same rings, same pistons, no cylinder honing, etc - so it was *not* a rebuild. This next build will actually be a build, but I will go back to a turbo that is equivalent to a 2871.

MY car/SNC motor has 98k miles on it now, and I've done 3 complete timing belt jobs - I'm a bit anal about maintenance. There is absolutely no sign of wear on the crank nose.

But yes, if you are buying/just boosting a SNC motor, you defintely need to check it out first. If it looks fine, tear down the front of the motor, do a complete timing belt job, and make sure to replace the key and bolt. After that, just do your next timnig belt job at ~50k miles for peace of mind, again replacing the bolt and key (which should be standard practice anyway). Repeat. For years and years.

[Flyin96M]

Eh, the SNC issue is moot if you keep up with maintenance. I've put ~66k boosted miles on my SNC and it shows no sign of giving up. I have never ran less than 12psi from a GT28R, with the average being 16psi from the same turbo (I'd have to check my notes, but I would guess about 40k miles at 16psi from the GT28R). Once I put in rods, I went to a 2871 at 18psi for a bit, then went to an even bigger turbo for a while. And FWIW, when I put the rods in, I just replaced the rods - same bearings, same rings, same pistons, no cylinder honing, etc - so it was *not* a rebuild. This next build will actually be a build, but I will go back to a turbo that is equivalent to a 2871.

MY car/SNC motor has 98k miles on it now, and I've done 3 complete timing belt jobs - I'm a bit anal about maintenance. There is absolutely no sign of wear on the crank nose.

But yes, if you are buying/just boosting a SNC motor, you defintely need to check it out first. If it looks fine, tear down the front of the motor, do a complete timing belt job, and make sure to replace the key and bolt. After that, just do your next timnig belt job at ~50k miles for peace of mind, again replacing the bolt and key (which should be standard practice anyway). Repeat. For years and years.

I think TD was trying to say that a turbo is a better choice if you have a SNC motor as the SC would put additional stress on the crank.

[Rob®]

haha. I saw "TurboDuane" not "SuperDuane" or something like that, so I figured he was a turbo guy. I read it as he went with the smaller/less boost FM setup so he would not put more stress on the crank. Oops.

[SirHustlerEsq]

It really comes down to one thing: Do you want a set-it-and-forget-it boost solution or do you want something that will keep you busy fine tuning a lot over time until you get it right?

I was going to comment, but...

I humbly beg to differ. I had a turbo on two different Miatas and I did not have to fiddle with it to keep in running at all.

I was going to comment, but...

With the right amount of money anything is possible I guess :)

My turbo/drivetrain is solid. I'd done about 40-hours of track time on it and haven't touched it aside from one check to make sure everything was good. However, when was the last time you saw "anything that gets hot and vibrates" safety-wired with Inconel wire? I think just about anyone can build a reliable turbo Miata, but there is a very specific recipe for success that very few understand. I've paid dearly for the learning process, but the end product puts a huge smile on my face.

[Yeller90]

So whats the preferred turbo set up?

[Rob®]

So whats the preferred turbo set up?

LMAO. That's even more of a debate than turbo or supercharger. Most Miata people go with small turbos for some odd reason. And they seem to love cheap/inefficient setups as well. The ones that don't are treated to excellent gains, yet most others still refuse to spend a real amount of money on a setup.

But to actually "answer" your question, you need to know what you want out of the car. Drag car? Light to light racer? Highway pulls? Big power numbers? Lightning quick spool? Fun around town cruiser? Price range? How involved do you want to get with it all? There are a million questions...you need to think of the end result you want, and work your way back from that.

[SirHustlerEsq]

So whats the preferred turbo set up?

For a street car anything off the shelf from FM or BEGi with inconel studs on the hot-parts, or use ARTech (which is an anomaly because he is cheaper than the competition and does insanely better performing and more reliable work) . For a track car you probably want a v-band set-up with schedule 40 pipe on the manifold, Burns double-slips on the WG dump, expensive TiAL v-band clamps on the DP joint. You also want gussets on every weld in the manifold and downpipe, and hopefully the manifold and DP were argon back-purged. It was not much more expensive for my ABSURDflow parts (which I bought after the first kit didn't work out) but the challenge lies in finding someone who knows what they're doing.
This is my car with the turbo out (I had it out, safety wire check, and back in the car under one hour). You can look at something like this and see why it takes more than a day to build his turbo manifold and why $800 for that manifold is a bargain when you look at the competition who robot weld and still leave a little to be desired.

[BFPW]

I have a question. Those little filters at the top left of the picture...where do you get them? Just any normal auto parts store?

[Rob®]

I have a question. Those little filters at the top left of the picture...where do you get them? Just any normal auto parts store?

Yup. Mine looks identical to the one posted, just blue. I got mine from Autozone. Pretty much any auto parts store that sells ricer crap will have them - I don't think NAPA does. Walmart might even have them...if the store sells cheap colored intake air filters, chances are they will have the small breather filters.

[MoonieGT]

This has been a good read for me. I'm looking down the road to adding power to my '99 and trying figure this out. I want to add coilovers, sway bars, and stickier rubber first but then it's FI time. My #1 main concern is reliability at the track. I want the car to be able to handle a two-day event when the ambient temps are in the 90's with no overheating. I'm leaning towards SC, but I'm not really sure at this point. Ultimate power is a far second to reliability. If that means being conservative on boost then so be it... I'm probably a year+ away from buying a system, but the research begins now!

[miataspeedracer]

Well, my intercooled M45 has been dead reliable since I've installed several years ago. Other than a few worn belts, I've had zero issues with overheating or any other mechanical drama. Drive it to the track, beat on it all day or all weekend, then drive it home.

[Yeller90]

Seems to me no matter which way you go you have to put in a fuel management controller, thats where it becomes even more confusing at least to me. I have read up on the FM kits and BEGI kits as well as others, there seems to no clear cut winner as to "the perfect" kit for a Miata. Though the way my year is finishing out, the 2011 upgrade is not looking good so I will have plenty of time to do more dreamsearch

[ken o]

I would do both.

[Rob®]

You really can't go wrong with either if you don't take shortcuts or cheap-out on certain stuff. Perfect for you is completely different than perfect for me, which is just as different from my girlfriend's idea of perfect.

If you're not looking for the absolute highest amount of power you can get, I would HIGHLY suggest looking at the various levels of support for each ECU you are considering, and pick the one that you are most comfortable with. Make sure you get something you can either tune yourself or that your tuner knows. There is TONS of info out there for a Megasquirt of just about any vintage, but an SDS system is fairly rare (from my experience anyway - I've only known one person to have one). I don't know about this area, but I know pretty much every single tuning shop in the Orlando area can and will tune an AEM setup, so you couldn't go wrong with one there - and on the other side, if nobody here will tune one, you're pretty much left to fend for yourself. FM's LINK is ancient, but gets the job done (cheap plug: I'll sell you mine). There are no more updates for it, but there is a TON of info out there for it as well. It won't make the most power, but that doesn't matter unless you're gunning for purely bragging rights or whatever. See where I'm going with this?

I would suggest against going with bandaids (power cards and crap like that), but lots of people do with success. So again, it really comes down to what you're comfortable with.

[MoonieGT]

I'm trying figure out what needs to be done to the car to make it withstand track duty. From the research I've done I think I'm leaning towards a SC setup. Ultimate power is distant second to trouble free operation at the track. I like the cooler outlet temperatures of the Rotrex, but there seems to be a lack of support and upgradability with it (a promise of a stage 2 with IC has been unfullfilled for over a year now). In any event, I'll probably end up with an MP62 kit from TDR or a Rotrex kit from 949. My whp goal is a modest 160-180. After I've gotten the hang of that I might want to up the power to the 200-220 range.

What else does the car need to withstand track days? Radiator upgrade, IC, coolant rerout, ect? Can you track a SC miata with no IC at 5-6 psi or is that a formula for disaster? My car has an upgraded exedy clutch in it from the PO by the way...

[Rob®]

I am a die-hard turbo guy...that being said, I would recommend a supercharger for you. LOL Figure that one out. Honestly, if my girlfriend ever gets her Miata, I would probably supercharge it for her, just to get more experience with them. And not go crazy and have her car down all the time too.

I have some supercharged Miata experience, but very little experience actually playing with one. I know a handful of people with them, most are track junkies. When we used to do HPDEs, I would have to burn myself hunting down loose bolts and/or melted coolant lines; the SC guys would sit back and laugh at me between sessions. I digress..what was my point? Oh:The added heat from any amount of boost for extended periods of time is not good. Especially in Texas heat. Going back to my little actual SC experience, I personally do not know if a Miata will be able to take 5-6psi nonintercooled at a track day. I would imagine it could, but I personally would not recommend it on theory alone. I also am a firm believer in overkill on certain things.

If I were to get a SCed track car, I would have an upgraded radiator, intercooler of some sort, and ducting/sealing out the ying-yang..at the very minimum. Any way you can think to reasonably cool things down, do it.

I *just* did a coolant reroute the last time I tore my setup apart - I actually have yet to fill it with coolant since I bolted it all on - and I have plenty of track and street time on my motor with no damage from lack of coolant reroute with years of high boost. Obviously I have yet to compare water temps before and after, but I have never overheated without the reroute (and my gauge reads actual temp). Again, by theory alone, heat is your enemy, so a coolant reroute is a great idea. You can argue if it's "needed" but it's not a bad idea by any means.

[MoonieGT]

I'm in the overkill camp for cooling as well. I want to be one of the ones "kicking back" between sessions. I think I'm interested in the Rotrex for now. I'll keep researching and see if I find anything that knocks it out as a contender. In the mean time I'll be doing suspension first. Then I guess I'll get all the cooling mods taken care of (bigger radiator, better fans, coolant rerout) and probably replace exhaust from the block to the back. That should give me a good base to add the Rotrex to...