bmccord

hello all. I am new to miata's but am no stranger to boost. After finally getting my stockblock B16 turbo crx tuned and out to the track, I have decided to take that car back to NA and transfer everything over to a Miata. It weighs about the same and is RWD. I basicaly have everything I need other than engine management and a manifold (which I will make). Here's my first question, if you had a choice which year would you pick and why. I like the idea of a 94+ due to not having to swap out the 1.6. Is there an OBD-0 miata? I am very familiar with that platform. I need a fully tunable non-hack management system that also many other people are using but is not ridiculously expensive. I have looked at the Link system but it is pretty pricey. That's it for now. Thanks all.

Brett

brgracer

iTrader: (14)

I said it before, and I'll say it again, I'd choose a 94 for the following reasons:

1) still OBD-I so no emissions issues with aftermarket ECUs and electronics
2) upgraded subframe bracing added already unlike 90-93
3) ever so slightly less CR, making it more boost friendly
4) real oil pressure gauge (poor man's knock sensor)
5) already has the bigger brakes and larger pinion gear size unlike the 90-93
6) 0.2L of extra displacement over the 90-93
7) available with the Torsen diff so no need to swap

a 95 would be just as good, the only difference being the CR, but that is a side issue since IIRC we're talking about 9:1 vs 8.8:1 YMMV.

As for engine management, I can't talk from experience.....yet....but the Megasquirt is aweful cheap compared to a full standalone and pretty much just as capable from what I have been reading....

jayc72

iTrader: (14)

I would buy the best miata my budget allowed. Get one with the absolute best body you can find, everything else is minor to fix. 94 would be my pick too, but I wouldn't buy a beat 94 over a minty 92.

sbrian2

iTrader: (12)

Actually, 95's have the same CR as 94's until the late build 95 cars. My R package is a high CR ratio car and has 1 piece axles instead of the 2 piece axles in the early 95's. But, I would take a '94 over a '95 for the real oil guage.

bmccord

Thanks a bunch guys. After reading up on this last night, I had pretty much decided on a 94. Now, about the injectors... any ideas if honda injectors will fit? They look almost identical but I am not sure if stock Mazda is a high or low imp. I have a set of DSM blue top 450cc injectors that I run right now that have been flowed and balanced that I would love to use however they run via a factory resistor pack (old honda). As for that, I will look into the megasquirt system. Just curious what the absolute max the factory bottom end can take (proper tune, obviously)? I will be running one of my T3/T04E 60 trim .63 a/r hot side turbos and I would love to run 20-24 pounds on C16. The car will not be a daily driver so reliability is not a concern. When it goes boom, I will get another motor from a junkyard and build it, but for the time being, I will get my feet wet in the miata world with a stock block. Also, is the lug pattern on the miata 4x100 and what offset. I have a set of slicks i run on my honda that are 22x8.5x13's on lensos that would be great for low boost apps. The factory offset of my honda is 42mm and I am hoping the miata is similar. I also have a set of BBS RC's with 205/45-16 yoko paradas that would be great for this if the offset is correct. Anywho, thats it for now. Thanks so far. I have used the search function quite a bit and that saved me tons of questions but sorry if I ask some stupid ones.

Brett

Braineack

iTrader: (62)

high ohm nippon-deson "f" connectors.

it will go boom somewhere around 250-300rwhp. 15psi seems to be the limit on stock internals.

4x100 +42 i believe.

bmccord

thanks a bunch. I thought it would handle a bit more. I have been running 354 whp on a stockblock 11.2:1 motor. Is it the rods or the pistons that is the weak link? Are the block sleaves pretty stout or are they floating sleaves like hondas. Thanks. So how long do you think one would last at 350-375 rwhp @ 11.8:1 afr and a conservative spark map?

fmowry

iTrader: (8)

The rods are the weak link. You can get over 300whp with a good tune on a 1.8 stock '94 block. RacingMazda was the king of the junkyard motors for a while. Obviously at that point a little knock can kill the motor though.

The DSM injectors will work fine with the right clips and the resistor pack or source some RX-7 TII 550s for plug and play high imp injectors.

Frank

bmccord

thanks frank. I had heard that the rotory 550's would work. what would be the most common management systems you guys run. Point being, on my honda, I got someone else's map to start with and then worked it from there. I have a full PLX wideband unit to street tune and somewhat WOT tune it but its nice to have it mostly worked out before you hit the dyno. Are there any cracked programs out there for the factory ecu. @ know in handas, there are a half dozen good ones and I am running off one right now. I have a chip burner and programmer so all I really need is a program to access the tables. Thanks.

bripab007

Calling the rods the "weak link" is accurate but funny, in that they can handle three times the stock torque levels.

bmccord

very true. Perhaps I should say..."mechanical piece that will fail first when being forced to output way more than designed to do so"

On a side note, I will be running a rather large 4 puck ceramic sprung hub clutch w/ a alum FW...just how much load can the rearend take. I would imagine a 6500rpm dump on slicks would not last long. I have heard about 350whp or higher depending on launch method...

bmccord

sorry, I am full of questions. After everything is up and running at low boost I will pull the motor and do crower rods, JE pistons, total seal rings and not sure about bearings yet but neeless to say my end goal is to upgrade to a bigger more efficient turbo such as an SC61 or SC70 and be in the 450-500 RWHP range. basically a 10 second pump gas car. that is why I am trying to source a good management system now so that there is plenty of support when I really need it. thanks

beerslurpy

Youre gonna need headwork for that kind of turbo to be worthwhile.

Al Hounos

Megasquirt is the best engine management available for the miata, without spending $1500+ for an exotic ecu.

bmccord

good deal, I was looking on the website and I think that will be the way to go. I didn't see a price however for the kit. Also, is the 94 head flow that bad? I have build several stock head 1.8L Integra LS motors with well over 400whp. Now they would obviously make more with a P&P, better intake mani, etc. Anywho, thanks. This is helping soooo much.

Brett

bripab007

You'll break the '90-'93 differentials with stock power (~90rwtq) if you launch/wheelhop them. I ran mine for about a year with ~150-175rwhp, being extra super-duper careful. Was a guy on M.net who went through 6 of them, 4 or 5 at stock power level (he autocrossed).

The '94+ differentials will stand up to a LOT more abuse, as long as you don't allow excessive wheelhop. Plenty of 350+rwtq folks still use the stock differential with some care. Bangin' Gearz was running 473rwhp on his, but I'm sure what kind of abuse it saw. I wonder what the guy running the 616rwhp Miata is using. He might have gone straight to a Ford 8.8".

UofACATS

iTrader: (1)

Just laughed out loud. I actually have a ford 8.8 just sitting there...

Maybe I'll trade it to some psycho/death-machine who doesn't want to break the 1.8.

Straight up. Takers?

fmowry

iTrader: (8)

They coulda kept GTX con rods in there though. Or maybe GT-R conrods. Damn these weak rods.

Frank

PaKMaN

iTrader: (1)

Frank will the 1.8 tranny hold up 400whp? Obviously not powershifting it but I mean shifting rather quickly

bripab007

Bangin' Gearz was also using a stock 5-speed tranny, as was FM's last C&D shootout 300+rwhp build.

The 616rwhp Miata I mentioned early was using a 6-speed and finally broke it, but the word is that the 6-speeds are definitely stronger.

You need to do some searching on M.net to find out what trannies the higher-power folks have used. Mark Kulak, Ric at Racing Mazda, Skyler, etc.

If I were shooting for 400rwhp, I'd use a 6-speed with the 7" rear-end and 3.3 ring gear. But I've never been a huge fan of "launching" my car or going to the drag strip, so maybe that point's moot. Actually, I'd never build a 400rwhp Miata in the first place unless I were going to drag-race it, so that point is really moot.

If I were to do that, I'd just go with a Ford 7.5" or 8.8" independent rear-end like the V8 swap guys use and get a custom driveshaft to mate it with the 6-speed tranny. Would still have to make a tranny cross-member or adapt the PPF to the two (seen it done once on an LS6 swap). Heck, at that point, it'd probably be worth it just to get a custom bellhousing or adapter plate made to mate a T-56 tranny to the Miata engine...and at that point, it's no longer a Miata, so you might as well just put a V8 in it

These are merely one man's thoughts