ok, so i want to buy an older miata, prolly first gen, and have it for my project car. but what do i do with the engine. here are my options i'm thinking of, which one do you all think is the best...a) keep stock engine, but put a supercharger on it, b) keep stock engine, but put a turbo kit on it, c) get the 5.0L V8 conversion kit, or d) 5.0L conversion kit, plus a supercharger. obviously option D would give me the most power, but wouldn't be too cost effective. just imagine it though, you roll up next to a miata, thinking it's stock, start to race, and then you hear the growl of the V8, and the whine of the supercharger

 

I do not think that a 5L V-8 would look stock in the car, because I remember when Mazda showed a Miata V-6 prototype, it had a huge hood scoop to hide the engine. But 5.0 in a Miata is unreal power, faaaaast. However, back to reality. I would suggest turbo as well, because you can have more flexibilty with boost adjustment, and not so much with the supercharger.

 

Look who showed up at last year's Protege meet in Red Deer.

I did not speak to the owner but remember from some articles that the Monster Miata was not available as a kit. Only way to get one was to sent them your car or one that was already built.

 

How would that throw off the weight distribution though, a heavy iron-block V8 in a light-*** car? The engine has to weigh a lot more than the B series engine in there.

 

If you can do a 5.0 and it's not too expensive that is what I would go with, but I would keep it NA. Personally I would get a good 4bbl instead of the fuel injection but that is just my preference. And damn sure find a limited slip with so little car to hold it down.

 

What about a rotary? a little 1.3 liter twin Turbo would be fat. Especially in a small car like that.

 

Now you're talking.

 

www.v8miata.com

the kit price is $3,995. for them to install it costs $16,900. how much would the engine cost, anybody have any rough ideas? the whole process only adds an extra 250lbs to the car. it makes the weight balance 53/47. it retains the stock look, no special hood or fenders needed. the only way you would be able to tell it's got the V8 is the rumble. but a ricer who's trying to race you is probably sounding off his bumpin system so they won't hear your car.

 

I just read about it on that site, man I want one! All that torque in such a small car

 

exactly, you'd never expect a thing. and then you hear the growl.

 

You'd be suprised... there's a reason why the BP is so strong, and a reason why Mazda ditched the BP in the 3rd-gen cars. That reason is weight. The BP is VERY heavy compared to most other 1.8L 4-cylinders, but the Ford 302 is quite light as American V-8's go. It only weighs about 100 lbs more than the BP with aluminum heads and engine accessories. The Mustang's Tremec T-5 tranny actually weighs LESS than than stock Miata tranny.

However... the Miata 5.0L swap is NOT a project to be taken lightly. Although the engine fits more easily than you might expect, you will still essentially be replacing most of the car, and the hardest part to deal with- believe it or not- is the rear end. 302 cubic inches of torque will turn any stock Mazda IRS rear end into shrapnel; most conversions use T-bird rear ends, but making them fit is a bear.

My advice? Do NOT attempt this project unless you're good at custom fabrication, you're willing to spend a lot of time doing this (like months), and you ENJOY working on cars. Note that I didn't say you CAN work on cars. You must ENJOY it and view stubborn problems as rewarding challenges, not annoyances. If you don't, you will probably wind up wanting to kill the car. I have a friend who's not a mechanical dummy, and his V-8 Miata project has been bogged down for over a year by assorted parts fitment problems.

Oh yeah, my opinion? Go turbo. You can makes GOBS of power this way, and so many people have done it that all the common problems have already been worked out and extensively documented. I want a turbo Miata so badly it hurts.

BTW before the discussion goes further, let me kill another couple of engine ideas about Miatas...
1) Rotaries do not fit in a Miata without extensive mods to the unibody. The problem isn't the engine's size, it's the round shape and the fact that the output shaft comes out of the middle of the engine, not the bottom... BIG problem in the Miata's low-slung chassis. Racing Beat built a rotary Miata soon after Mazda released the car, with the original intention of making a swap kit, but gave up on the idea after having to fabricate an entire custom firewall AND tranny tunnel to make the tranny clear, then redoing most of the interior to accomodate the above-mentioned modifications. The Ford 302 V-8 swap is actually much easier!
2) V-6... also won't really work. A couple of people have swapped K-series Mazda V-6's into Miatas, only to spin rod bearings after the engines starved for oil. The K-series was designed for FWD and can't lubricate itself when it's turned lengthwise in a RWD car. Mazda even studied the idea but gave up after examining the cost of solving the oil starvation problem. Mazda also trotted out a Miata a couple of years ago with a Ford Duratec V-6, but this also wasn't a good idea as the swap was very costly and required a huge hood bulge. My opinion? Fuggetaboutit.

Good luck! I love talking about Miatas.

 

There's a guy here in the Twin Cities with a car called a Sunbeam Tiger. It's a little British roadster from the mid-60s that originally came with a Ford 260 V8. It now has a built 302 with a 4bbl on a high-rise intake. I've also seen a 350 Chevy in a Datsun 260Z. Sounds a lot like what you're talking about. And you're right; it does sound like a lot of fun! I say, go for it, feasibility be damned! The ends will justify the means.

Man, I wish I had the money/time/space for a project like that.

 

5.0L blocks are plentiful but you may have issues finding a Mustang setup at a cheap price (lots of truck powertrains though). I would say an additional $2,000 getting a motor and transmission together (I don't know how much it would be crate, and I wouldn't drop a junkyard motor straight in without rebuilding it first). Get a good transmission, have it built up and then find a nice block and go to Edelbrock and spend some money on a good set of heads/cams/etc and a 4bbl (probably 750cfm or higher). Run dual pipes to the back just for the hell of it. I recommend going with the carb so you can eliminate the engine electronics you would have to mess with on a fuel injected model. You can either run a Duraspark II setup or get a good standalone ignition system (MSD, but there are some others). About $5k doesn't sound too bad, but it will be a lot of work (and could be a lot more depending on how good / bad the kit is).

 

Actually, a truck powertrain isn't all bad. The late-model Explorer engine actually came with the best heads of any factory 5.0, although I'm not sure if they're iron or aluminum. However, you WILL need to get a T-5 tranny from a Mustang; do NOT go automatic, the Ford AOD automatic is a power-sucking piece of crap.

Actually, if you're interested in using EFI (a necessity to meet emissions standards in many areas) you can buy a stand-alone, plug-in 5.0 EFI wiring harness. They're intended for the street rod market and include wiring for all the engine sensors; just add an ECU and plug it in to a 12V battery and you're good to go. Although I've never actually priced one, I've been told that these harnesses are quite reasonably priced.

 

Tigers are cool little cars, although I've read that they're a handful to drive- combine 60's British suspension, an ~80" wheelbase (shorter than a Miata or Porsche 911), and big American V-8 torque, and you've got a recipe for handling that's sometimes exciting for the wrong reasons. I'd still like to drive one though.

Also, one of the most amusing factoids about the car... Sunbeam was almost bankrupt when the Tiger was being designed, so they based the Tiger on the existing Alpine sports car, but they didn't quite have the dough to produce tooling for a redesigned firewall to clear part of the V-8. Their solution? Since the car was intended for limited production anyways, they had the biggest, strongest guy in the factory get into the engine bay of each Tiger with an 8-pound sledgehammer and "massage" the firewall into the correct shape before the engine was installed! Therefore, every Tiger features a great big factory-original dent in the firewall.

I know this is a sidetrack, but I just love that story.