If you wanted a reliable 250BHP all day long, what would you use?

[Plus4E]

The MX5 is a cracking car, but it needs more grunt, and I know that in 6 months time I'll have explored the limits of grip and will want to go faster.

So, engine transplant seems to most likely solution. There are tuning options for both the 1.6 and 1.8, but they seem to be a reasonable amount of money for a setup that will leave me with a stressed engine that doesn't deliver the outright power I'd want.

Something that will make 250BHP all day long would strike me as a better option, but comes with the fabrication issues and lack of "bolt on shiny bits for results".

My initial thoughts are: SR20 - for obvious reasons, 200BHP out of the box, 250BHP easy with simple mods, comes with a gearbox etc. 1UZ - it's a V8, which is reason enough in itself, but more over it's NA, so preserves some of the characteristic of the car, although I believe it's quite a lazy V8, compared to the revvy 1.6 that's in there now. A 1UZ donor isn't going to come with a gearbox though. But it's a V8 (did I say that).

Other suggestions? The above have been done, so aren't utter fantasy. I have a B234R in the garage too - 225BHP from the box, and string enough for silly power, but very tall (others have failed to install it for this reason), needs a gearbox, and is reasonably heavy. It'd be great to make it work, but I think the first two are both better ideas.

[Sidewaysfun]

double post

[Sidewaysfun]

Im pretty sure there is another v8 conversion kit out there? I seem to remember looking into it a few years ago when I had an mx5...

I'll see if I can dig it out.

http://www.monstermiata.com/

Eek, seems quite expensive

[Rubix_Cube]

sR20 doesnt go in "that" easily...

[Dr Bob]

for reliability i'd go NA but wouldn't a big V8 make it a bit nose-heavy? especially in a wee car like an mx5

i'd probably be thinking more along the V6 route as a compromise

[Johnny]

I would just FI the mx5 to be honest .... yes it will stress the engine a bit ... but whats going to happen ?? .... if it does go pop .. and thats an if, replacing the engine is going to still be easier than dropping an sr or V8 in there

And you keep the same handling that the mx5 is famous for

[Si]

I'd go for the 'finish one project'...

If not that, then MRX5.
EDIT: Shit, you said reliable. SR or VAG 1.8t. ish.

[Prior]

Turbo it for 200bhp. I really don't know why youd want anything more than 200 unless it was a track car. Mine is pretty tail happy with 150 and the LSD and a lot more grunty than the other bog standards I've driven.

[Actual_Ben_Taylor]

YB Cosworth

[Plus4E]

It is for track. Having stuffed my daily on a track day, I bought the mx5 to daily until the Legnum is fixed, and the the mx5 will be the track toy, keeping my daily VR4 less stressed and keeping me on trackdays whilst Project Institutionalised rolls forward.

It'll be tracked as a 1.6 at airfield days over the winter, but after that I'll want to do something, and it's unlikely to involve tuning the 1.6.

Sent from my GT-I9100 using Tapatalk 2

[30psi]

S2000 engine will be my next engine transplant. 10bhp short of your target.

But then, putting that in to an MX5 begs the question why not just buy an S2000?

So ignore that for now. Price wise and I guess familiarity - I'd go with the SR20

[Jem]

The 1UZ is a cracking engine, not too heavy and will be more than enough power in a MX-5, oh and they NEVER break.

[Plus4E]

Of course, I'd be conscious of changing weight distribution, but then an iron 1.6 with aircon is going to rack up reasonably well against an ally SR20 with minimal ancillairies. The MX5 box is, I believe, quite hefty as well for a car of it's size. The 1UZ with it's extra bank might tip the scales a bit though.

[30psi]

Don't some of these in the US have LS series dropped in (I use that term loosely)? Wonder how they are with the weight changes?

[frisbee]

I would drive the MX-5 for a bit as it is, after initial aspirations to modify it I've really grown to dislike it generally.

[Plus4E]

Don't some of these in the US have LS series dropped in (I use that term loosely)? Wonder how they are with the weight changes?

I think the Yanks have a different interpretation of the impact of weight distribution changes. They tend to avoid corners for some reason...

[Plus4E]

I would drive the MX-5 for a bit as it is, after initial aspirations to modify it I've really grown to dislike it generally.

As I say - that's kind of the plan, but it's useful to have longer term ideas cooking in the pot.

I've driven them before and liked them. And now I'm driving my own and liking it too

[30psi]

I think the Yanks have a different interpretation of the impact of weight distribution changes. They tend to avoid corners for some reason...

Hmm stereotypes I think they also fit leaf springs and 9" axles instead of the IRS lol

[zeppelin101]

Supercharge it. You won't get 250 without judicious choice of bits and some extra work but nearly 200s is a doddle with a mini 'charger and they go excellently.

[Kango_V]

hmm s2000 engine sounds good. Oh it uses the same 6 speed box as the s15.