BlownCoronas Mopar Miata

[BlownCorona]

Where do i start. 

A while ago my brother started building an mx5 for his girlfriend and ended up with a fairly straight, but de registered rolling body, offered it to me for free and i was keen for a future track car project. 

I also happen to have a job which involved crashing cars, and thanks to a certain american standard roadside barriers must meet, we crash a lot of Dodge Rams. with plenty of v8 engines kicking around i hatched a plan and proceeded to talk about it for at least a year without actually doing anything about it. 

then the engine blew up on the corona, so while i wait to save up money to build that engine properly, i thought id make a start on this one, which by all accounts should be nearly free, with the only big ticket items needed being a roll cage, a diff swap and a driveshaft. 

 

So last weekend i dragged the mx5 into work, where i have all the tools i need to build a race car. and over the week started the efforts to remove the engine. 

Now that sounds easy, but boy was this truck fucked up. while the engine faired very well with the only damage being an engine mount ripped out (block still fine) and the starter motor wanged in (i have alot of spares). the chassis was bent at near 90 degrees around the engine, i also didn't really want to remove the trans. 

i started with a 9" angle grinder and removed as much fucked body and frame as possible. 

 

i then undid the remaining mounts and then promptly discovered this engine doesn't have lifting points? strapped it around some dubious strong points and tried to lift it out with the forklift. 

it rapidly became clear that the turbo fucked chassis was going to make it impossible to get out. so packed up, went back to work and had a think over the next few days. 

 

that brings us to today, what i had decided to do was cut the chassis in half just behind the trans and lift the truck off. so out came the 9" grinder again and i began by cutting access to the rails around the fucked body, and then trying to cut the rails with the grinder. sketchy at best. so thought fuck it, step it up a notch eh? though this was actually much safer. 

Gas axed the rails and out she came! 

 

[BlownCorona]

The engine is a nothing flash 4.7l V8. making a reasonably flash for an mx5 310hp and 400 something nm 

filthy, but not an ugly motor which is nice. 

i plan to keep the automatic and manualise it. the trans computer should be able to to be programmed to behave like a sequential manual trans and ill make a big gear chopping stick. and the goal for this car is to be as fun as possible for as cheap as possible. it wont be a competitive race car. but it will be a stupid amount of fun

[BlownCorona]

It'll fit. probably

 

 

[Dell'orto]

Seen the Hellcat Miata in the States? This puppy will fit like a glove*

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*when you have XL hands and XS gloves

 

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[BlownCorona]

i have, that shit crazy fast.

there is also a Mercedes M120 v12 going into one, that one fits like a glove too, an XXS glove over an XXL foot. 

fits none the less. and it will sound like a zonda if hes done it right, 

 

funnily enough we also have one of those engines at work, in an sl600 race car we built, its a gigantic engine, truly a monster. sadly the motor is fucked, so its getting similar treatment to my car, except we'll use one of the Hemi 5.7 beasts we sometimes get. 

i figured i didn't need an additional 25% power over the 4.7 in an mx5, with the added bonus of way more spare parts for the 4.7. cheap cheap

[RUNAMUCK]

Those 4.7's are actually a Merc engine that Chrysler borrowed. 
Ive seen what your work does. exactly seven years ago this coming friday I went to a demonstration out the back of ruapuna. there was cars being smashed up, and beer and pizza. it was legit as fuck. The lady Next door to me works there too. Once in a while (not for a while now though) I'll hear a Ram taking six goes to back up their driveway when they need to do a run to the dump, or drop off something large theyre bringing home. 

I wholeheartly approve of this swap.  goes hard for what it is springs to mind..........

[BlownCorona]

It's still beers and pizza and car crashes. I'm lucky. 

The IT guy also knows you nismocapri on other areas of the Internet and mentioned you lived next to office manager. Small world. The road legal ram is gone unfortunately. 

It certainly should go hard for what it is! 

[RUNAMUCK]

Rip R4M IT.

[BlownCorona]

on the suggestion of runamuck, i posted in this forum looking for wiring info, 

and user on there was very kind and gave me a bunch of info which should hopfully sort me out, i was gonna dump all the info in here but sort of cant be bothers, plus give those guys the traffic eh?

https://www.forabodiesonly.com/mopar/threads/4-7l-corsair-wiring-diagrams.440431/

 

also had my weld in 'project car' engine mounts turn up from speedway motors in america, grunty looking things! they are actually for the new gen Hemi, but for the price, i couldnt have bought the materials and if they don't fit the block then worst case is a redrill or a new engine plate. easy as! hope to have the engine "fitted" soon. 

[BlownCorona]

Got the final piece of wiring loom that I'll need freed up from the smashed truck. 

Compared to getting this out in tact, fitting the engine should be a dream! 

Stoked

[BlownCorona]

Romoved the front bumper and made the first grinder cut at lunch today. 

Wiped the radiator core support off to give a little more room to sling the engine in, this will get flanged for refitment later, and the hood will be pinned. 

[BlownCorona]

Yesterday I made some engine lifting points as weirdly this engine doesn't have any.

I assume they are under the manifold, but I have no interest in pulling the manifold off. 

These will also alow the use of an engine leveler as I hope to fit the engine and trans as one unit 

 

[BlownCorona]

An exciting day today! first test fit of the huge engine and trans into a mostly stock body mx5. 

first i started by cutting the 'ears' off the frame and firewall. forgot to grab a pic but its these parts. theyll need plates welded in to re-add the strength lost. 

this squares up the bay and allows the engine to sit close to the firewall 

 

then in goes the engine!

 

its SO close to fitting in unmodified. infact if i was to unbolt the subframe, id be able to fit the sump bowl past the subframe and the engine could sit down properly. 

however, i dont really want to have to unbolt the subframe everytime i need to pull the engine. which hopefully wont be often, except for during the build, but even thats enough for me. 

if i want to slide the whole lot in, ill need to cut maybe 60-100mm out of the top of the tunnel. a pretty easy job for the massive benefit of easy install!

 

trans hits here

 

sump just doesnt quite get over the subframe

 

its possible the unmodified hood may even close over it all! most of the bulk ontop is the wiring loom ect

what a monster  

 

 

 

 

[BlownCorona]

more progress during smoko and lunch today. building a race car at work rules. 

 

cut 100mm out of the top of the firewall and made two cuts down each side of the tunnel roof, pushing the tunnel up. once i know the engine fits the holes will be patched up. should make installs a breeze. 

 

 

came across the first real issue too. the exhaust manifold foul on the frame rails. i can notch these out enough to clear i think. however the drivers side manifold dumps right onto the steering shaft. 

 

flipping the manifold looks to be an option, and im contemplating the option of bringing the drives side exhaust around or under the engine and merging with the passengers exhaust, or crossing back under the trans. ill clearance the frame rails and see where that leaves me i think. 

 

not quite in, but its getting lower in the engine bay! should go down and back about 3" both ways

 

any ideas, shoot them my way! gotta say, i thought id be swinging a sledge hammer pretty early on to make this fit, so im pretty stoked on how its fitting, and can see why LS swaps are so popular in the states.

 

[RUNAMUCK]

Unbolt manifolds, and build log style headers after it's bolted up?*

 

 

*turbo headers teeheehee............

[BlownCorona]

yup thats my plan now. unbolted the manis and they cant be flipped, so ill carry on with the install and build manifolds later on to suit once i know where everything goes. 

 

not sure where id put the turbos??

[BlownCorona]

with the exhaust manifolds removed the engine went in the hole effortlessly. it will sit back maybe another inch, but my lifting attachment fouls on the edge of the engine bay so will need to sort that. 

new custom log manifolds dont look to pose much of a hassle. they will probably need to be installed once the engine is in the bay though, but we'll see how much clearance i can make, haven't used that sledge hammer yet...

pretty pleased with how it fits in there. the bonnet wont be shutting any time soon though, but a muscle car style hood should sus it and look pretty stout too. excuse all the truck spec dipsticks and wires all over the show. these will be fastened and trimed to suit. 

it sure is a big engine! looks pretty snug down in the engine bay properly. 

 

now comes the slightly harder job of fitting the engine mount kit and working out a suitable gearbox mount.

 

[RUNAMUCK]

Can you lower the profile of the engine by reversing that throttle body housing somehow? Reroute it back into the heater plenum?  A muscle car style bonnet will work in your favour two fold. Bonnet clearance, and if its open at the back it will aid air which has been through the radiator to exit the engine bay. 

[BlownCorona]

nah that throttle has to be where it is. its part of a huge manifold. which probably works really well. 

plus ive always liked cowl hoods. i think itll suit the mx5 well. heat dissipation will be an issue too, so thats a big plus. 

[RUNAMUCK]

Clamp that manifold to the bed of a mill, and machine the top right off it. then slap on an Eaton M122.  
We both know you want to. 

Maybe get it in and running first though eh?