Turbo Miata Engine

[sciff5]

A new lotus 7 clone came out that I'm pretty sure will be my next project.
http://stalkercars.com/models/stalker-mx5/

It's a kit car using the Miata as a donor, only it's 1000lbs lighter.

They have kits that allow you to put the Ls1 in these cars too, but I just don't feel like the Ls1 is a fit for these cars, and it seems to add about 2-300 lbs when everything is said and done. Mostly from the big t56 and whatever rear end you're using.

So I'm looking for a buzzy 4 cyl that sounds good and makes good power. A stock miata engine does neither.
Always heard turbo miatas were a hoot, but I wasn't sure how far you can push them on the stock engine. (looks like about 250-300whp). 300whp in 1350lbs would be pretty good but I wouldn't want less.

Any other 4cyl options that can get above 300whp without touching the bottom end?

So far I've considered K20/F20C/SR20(don't know much about the SR20s)
Haven't looked into the ecotecs/duratecs/or any euro options yet

[digitalsolo]

EcoBoost 2.3 would be stout.

[Cobranut]

Hard to beat the Ford 2.3 Duratec.  I've heard of plenty turbo'd ones putting out 300+ on stock motors, and I looked at a Focus a couple years ago making well over 500fwhp with a built motor, on pump gas.
Caterham uses them in their cars with very healthy results.

I have a stock 2.3 Duratec in my Focus. It has 220K+ miles on it and still burns no oil nor has any problems whatsoever.

[sciff5]

Hard to beat the Ford 2.3 Duratec.  I've heard of plenty turbo'd ones putting out 300+ on stock motors, and I looked at a Focus a couple years ago making well over 500fwhp with a built motor, on pump gas.
Caterham uses them in their cars with very healthy results.

I have a stock 2.3 Duratec in my Focus. It has 220K+ miles on it and still burns no oil nor has any problems whatsoever.

Duratecs are what the UK lotus clones use, but haven't seen that they can handle anywhere near 300whp reliably

EcoBoost 2.3 would be stout.

Ecoboost is too new, too expensive. Been thinking about an ecotec though

[Skeltic]

look into  Evenrudes  new  2  stroke v6's   engines they  put  out  a  ton  of  power and  weigh  like  200  pounds  for  the  block, yes  it  is  an  out  board  engine. Just  look,  you  might  be  suprised

[spacevomit]

Honda K24. (Or K20).

[wickedrx7]

Honda K24.

I agree. Honda K series.

[sciff5]

Honda K24.

I agree. Honda K series.

This would be the perfect engine. I don't even know if I'd go FI on it. A radical K24 with ITBs would be perfect and probably be able to produce close to 300whp, and reasonable torque. Sound awesome too!
I don't think I can run one of these without a dry sump though. I think they're especially susceptible to oil starvation when run longitudinally.

These cars produce A LOT of grip. If you're nutso and you pull the fenders off, you can run 275 hoosiers all the way around, so oil starvation is on my mind.

Part of the reason why a simple turbo miata engine is starting to look good. Cheap, can probably make 300whp bone stock, no oiling mods needed. etc...

[Grommit]

K series is a seriously solid choice speaking from the Honda Tech in me.

However, they are also very pricey to make a stout 300whp NA setup.  You are looking at a frankenstein engine which has been well documented to use a k24 bottom end (CRV, Accord etc) with a K20 head (RSX-S, SI)

There are a couple places selling complete conversions but last I looked they were 7-8k or so for a full engine.
http://www.kmodperformance.com/KMOD-K20-Engines.html - 260-280whp for $9k.

http://www.kmodperformance.com/KMOD-K24a-Crate-Engines.html
12.5:1 comp k24's about 285whp but that 11,000rpm rev limit though...yummy...

Now, do it yourself could be a lot cheaper, not sure on your level of experience.
I have a j32 engine sitting in my shop that needs a head, and an F20c engine that needs a sleeve (oval, still ran great just idles like shit lol)
Have you looked into a J Series V6 with a supercharger? Tons of torque, and they sounds pretty decent, otherwise I have seen ITB's on them and they sound GREAT...Also the J series is quite popular in sandrails and offroad buggy's. Plus at $600 give or take they are cheap.
http://www.arizonaperformanceimports.com/products.html

I ran my boosted Miata at 243whp for a couple years and it was a riot..sound can be changed with the use of resonators etc.

I want to put a 1.8T or J/K series in an RX8 still..pipe dreams for sure for a while still.

[Cman]

I ran a 1995 Miata with an FMII turbo kit for lot's of miles at 235whp. That's @12psi. There are other 4's that can make more but the BP is cheap and tough at that power level. It will be crazy fast in a 7 clone.

Steve

[sciff5]

How about 4g63 or 4g64 blocks?
Wide block versions mate right to the rx7 transmission with a b2600 bell housing.

I know colt boosting on here made crazy cheap power with his old colt with this motor

[Ebush]

I currently daily drive a 99 Miata and the power feels great for what it is. But if you want straight line speed the power would need to be doubled or the weight cut in half. If you want my personal opinion I suggest buying a Miata to drive around for a little bit before diving into different motor options. I picked up my 99 for $2500 and have been driving it for 6K miles with no issues.  Have you looked into the Exomotive Exocet? https://www.flyinmiata.com/exocet/index.php   For $7499 plus shipping and the cost of a donor vehicle you can be up and running...Weighs around 1400 pounds when completed.


If your not happy with the stock Miata motor you could supercharge it to make around 250whp or throw a K24 in it (around 6k for a stock motor, Kpro, and the subframe kit)

[65imp]

13b rotary.  IMO if you build a lotus 7 or similar it is a perfect fit.  Nonturbo rotary  motors last, sound unique and don't make the torque you don't want with go kart tires.

And around here you could prolly get a deal on one [emoji6]

[willcoop]

I saw a 13b locust at an autox one day. Because of the engine layout the oil pan was nearly on the ground and the owner said he had cracked it on pot holes before.

An Exocet seems like a great choice and the kit was designed to fit Miata turbo kits and LS swaps.

[sciff5]

Anyone know anything about german engines.
the 1.8t is somewhat interesting.

Even the s54 BMW I6 NA seems like it would be sick. They like to rev
Saw this video and it got me thinking:

This sound is what I'm going for. Quick revs, seems way more appropriate in a 1500lb car than the Camaro sound track.


More ear porn: