Another engine swap question - Miata.

fastx19

fastx19

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After reading Red128's idea of engine swaps in a 128, I was thinking about the X again and the different engines to put in it. Honda, Toyota, Dodge... Anyone have any idea why the 1.8 or 2l from a Miata has not been used? They are great little engines.

Just curious if I missed the boat somewhere on this.

Thanks.
 
Miata engine.. Meh, originally from the Mazda GLC began as 1600cc short nose crank which is prone to fail. Later Mazda fixed this in the 1800cc versions. Engine is long stroke, smallish bore, does not rev, does not have the "drive happy at the limit" feel the Lampredi SOHC does.
This is directly due to the con rod to stroke ratio of 1.56 (Econo box motor) -vs- the Lampredi SOHC of 2.0 or 1.8 (real race motor).

What it does offer is modern, four valve pent roof cylinder head, MLS head gasket, EFI and all that. It does good as a turbocharged (about 300 bhp/300 lb/ft reliable enough limit) engine for all the reasons it does not do well as a high RPM engine.

The GLC origins are why the Miata NA/NB has cooling system problems.

Having been around that Mazda twin cam for years, the Lampredi SOHC is a better design within the limits of when it was designed/produced. Properly done the Lampredi SOHC is as reliable-durable, far more interesting/fun to drive/run. Lampredi SOHC is limited by cylinder head design of two valve wedge combustion chamber and displacement.

In theory the Miata engine can be attached to the GLC family of transaxles to fit the exxe..

Given all that, why bother as there are FAR better alternatives to that power train.


Bernice
 
fastx19 said:
After reading Red128's idea of engine swaps in a 128, I was thinking about the X again and the different engines to put in it. Honda, Toyota, Dodge... Anyone have any idea why the 1.8 or 2l from a Miata has not been used? They are great little engines.

Just curious if I missed the boat somewhere on this.

Thanks.
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Lots of support for the Miata. It's a modern design that can make great power for a small, light engine. Should be readily available affordably. What trans arrangement would you use? Did they ever put that engine in a FWD chassis?
 
Dr.Jeff said:
Lots of support for the Miata. It's a modern design that can make great power for a small, light engine. Should be readily available affordably. What trans arrangement would you use? Did they ever put that engine in a FWD chassis?
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Ford escort GT and later ZX2. Focus was a different design with Zetec name. I have thought about the SVT Focus as I am more of a Ford person.

That said, brand loyalties aside, the JDM Nissan SR16VE seems like the right kind of swap for an X. Aluminum block, very short stroke, high power for size, and plenty of aftermarket support being part of the SR family.
 
X1/9-Ark said:
JDM Nissan SR16VE seems like the right kind of swap for an X. Aluminum block, very short stroke, high power for size, and plenty of aftermarket support being part of the SR family.
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~175 PS (129 kW; 173 hp) at 7800 rpm and 119 lb⋅ft (161 N⋅m) at 7200 rpm. Redline is at 8300 rpm.
"Bore and stroke is 86 mm × 68.7 mm (3.39 in × 2.70 in)"
with a 11.0:1 compression ratio.

Con rod length appears to be 144.9mm producing a stroke to rod ratio of 2.11..

Notable, the Lampredi SOHC 1500cc has a 86mm bore with 63.9 mm stroke,, Put a modern four valve pent roof cylinder head on that
Lampredi SOHC block, completely alters the results.. goes back to the Dallara x1/9.. which was producing similar power as this Nissan and others.

Any worthy performance motor has a typical bore size of 86mm to 88 maybe 90mm with a stroke in the 60mm to 70mm range.

Ponder where did Nissan, Honda and countless others got this idea from.. and why this is essentially universal.

Bernice
 
fastx19 said:
After reading Red128's idea of engine swaps in a 128, I was thinking about the X again and the different engines to put in it. Honda, Toyota, Dodge... Anyone have any idea why the 1.8 or 2l from a Miata has not been used? They are great little engines.

Just curious if I missed the boat somewhere on this.

Thanks.
Click to expand...
The Mercury Capri front drive convertible offered this engine as both a turbo (B6T) and normally aspirated (B6D) with a five speed manual or automatic. Both of these engines are a bit different from the Miata engine (B6ZE) in details around the crank in particular with other components lightened for the Miata.

The Capri’s are all over FB marketplace in various states of disrepair. Getting either engine with complete engine management from one would be fairly reasonable. It is one of the choices I have considered in the past. Act fast as I expect the supply of these unappreciated cars to disappear into recycling as there is little market for a broken down convertible with poor parts support. :)
 
While on the topic of bore size -vs- stroke, the Brits taxes engines (RAC horsepower rating) on bore diameter resulting in vintage Dino juice burners with small bores and long stroke, good low RPM torque (just like big Detroit iron). This is one of the reasons why so many Brit engines were low-reving (tractor motor), low burn efficiency, taller than needed engines..

Tax horsepower - Wikipedia

en.wikipedia.org en.wikipedia.org

The Italians took a different route to limit vintage Dino juice consumption, limit vintage Dino juice burners to 1500cc with any vintage Dino juice burner above 1600cc being massively taxed. This is one of the reasons and how so many Italian passenger moto vehicles ended up with "high strung" high revving motors that were designed to be run at near 100% all its service life. ala the production "race" motor for all..

German's have National pride/idenity in the unlimited speed Autobahn.. where top speed was valued as was large displacement vintage Dino juice burners to achieve highest top speed..

Detroit, US of A with vast reserves of vintage Dino juice and tendency for self indulgence made big Detroit Iron desirable with anything lesser un-worthy.. This holds to this day in the form of large truck & SUV sales volume.


Bernice
 
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Since I often ponder engine swapping my 850 sedan (honda D16z6, or electric), this thread has gotten me thinking about why people choose engine swaps. Is it just for more power? More modern engineering? The engineering and construction challenge?
 
fiatrn said:
Since I often ponder engine swapping my 850 sedan (honda D16z6, or electric), this thread has gotten me thinking about why people choose engine swaps. Is it just for more power? More modern engineering? The engineering and construction challenge?
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Jonathan: Your 850 berlina is a perfectly fine in-town or tertiary road-in-the foothills runabout. Sure, many drivers want more power because they are tired of trying to slipstream 40hp VW microbuses on the straightaways or they think they can do better than the well-resourced team of engineers, racers and shops full of the best manufacturing and testing equipment and the knowledge to properly use those resources. Since most engine swaps end as an incompleted project or as an unbalanced object that only its creator will tolerate, it is possible that some sort of brain chemistry anomaly leads the creator to mysteriously overlook all the possible dimensional, material, resource and financial obstacles that might stand in the way of completion of the project. A review of the literature in JAMA Neurology, Nature Review Neurology or Lancet may be in order for individual pondering their first engine transplant.
For guidance, the Fiat Abarth OT 1600 is Carlo Abarth's dream of a narrowly defined objective. Group 2 touring sedans, 1600cc class. To dominate the Lotus Cortinas. Too bad that Fiat blocked the finances to build the 1000 cars required to race in that class. Read the OT 1600 road test in the 1965 Road & Track Road Test Annual.
 
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PBS made parts to make it "easy" to swap in a Fiat DOHC engine into an 850. I don't think finding those PBS parts would be easy these days though. Of course that was before "modern" engines were available.
 
I think for most of us, who are primarily street drivers, we want to have a genuine and unique sports car like the X, but at the same time don’t want to be had between red lights by someone in a Mustang, let alone a Civic!

The reason there is so much discussion here on swaps is we want a certain level of speed and acceleration without sacrificing the weight and handling that makes the X1/9 so appealing in the first place. With something like a Mustang for example: the car is heavy and handles like crap so lot of negative aspects, therefore potential engine modification or swaps are a very wide range of possibility without compromising any positive aspects of the car.
For the X: making a durable 200+ hp can be quite challenging if you want to maintain, or at least minimize loss, of all the positive aspects of the car. IOW the margin of error is smaller.

I realize I’m stating the obvious to most, but to me that is why there is so much discussion about swaps, and why it’s so interesting.
 
X1/9-Ark said:
I think for most of us, who are primarily street drivers, we want to have a genuine and unique sports car like the X, but at the same time don’t want to be had between red lights by someone in a Mustang, let alone a Civic!

The reason there is so much discussion here on swaps is we want a certain level of speed and acceleration without sacrificing the weight and handling that makes the X1/9 so appealing in the first place. With something like a Mustang for example: the car is heavy and handles like crap so lot of negative aspects, therefore potential engine modification or swaps are a very wide range of possibility without compromising any positive aspects of the car.
For the X: making a durable 200+ hp can be quite challenging if you want to maintain, or at least minimize loss, of all the positive aspects of the car. IOW the margin of error is smaller.

I realize I’m stating the obvious to most, but to me that is why there is so much discussion about swaps, and why it’s so interesting.
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Reliable/proven 200bhp has been done years ago and for years now as the Honda K20 transplant. Power can be upped from the stock to what ever the current K20 "hot roding" allows, this includes super/turbo chargers.. There have been a number of K20 powered exxe that have sold on Bring a Trailer for not low cost.

Over the decades there have been many other alternative power trains installed into the exxe from other Honda, Toyota, Alfa Romeo_including the Busso V6, other Fiat_including Uno Turbo & Lampredi TC, Mazda rotary and others.

As for the stop light Grand Prix, notable would be an exxe built some years ago by Momi in Israel. This was a turbo drag racer with claimed ~800whp..
There were pictures posted on Xweb of Momi's drag racer, it was remarkably .... stock.


Essentially, yes the exxe chassis/suspension can be set up for drag racing.. Except that is not where the exxe chassis/suspension excels.
Even with just over 100 who, the exxe is a lot of fun to drive on a twisty back road where power is not nearly as important and overall behavior is.

As with any moto go fast, simply add funds, proper resources & expertise and it simply happens.. Question becomes, how good is the driver?

Bernice
 
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fastx19 said:
After reading Red128's idea of engine swaps in a 128, I was thinking about the X again and the different engines to put in it. Honda, Toyota, Dodge... Anyone have any idea why the 1.8 or 2l from a Miata has not been used? They are great little engines.

Just curious if I missed the boat somewhere on this.

Thanks.
Click to expand...
Miata engines are indeed popular for swaps due to their reliability and performance. However, compatibility, cost, and ease of installation might factor in. Research thoroughly and consult with experienced enthusiasts for insights on your swap project.
 
Bjorn Nilson said:
Mazda KL V6 engines would probably fit quite well in the X (there is a thread in the forum I can't find right now). The 2,2l Turbo R4 from Mazda 323/Ford Probe is another candidate.
Click to expand...

Here ya go, the Fiazda. I have definitely found the V6 swaps interesting as I’m not a big fan of inline 4cyls in general. As everyone here repeats, it all depends on goals.

Fiazda V6 Mazda KL powered track day X

Hello to All, First time posting, long time Fiat fan. I've read through forums many times for education/entertainment but finally have to talk about my Mazda powered X, Fiazda. I installed a 2.5 KL Mazda engine/tranny into my X. This is for track use only but could be installed in a street...
xwebforums.com
 
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