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Gingerbeardman
Gingerbeardman Reader
8/4/19 11:41 p.m.

As many of you who have read some of my previous threads are aware, I've had a life-long fetish with mid engine cars. The problem is, I always found a problem or sometimes "problems" with all of them that I've been fortunate enough to own.

I had marinated a homebuilt supercar in my head long enough to source parts, dedicate some time to CAD and collecting a sizeable assortment of fabrication tools to enable my fever-dream. I still may go ahead with this project at some point, but for now, the General had to go and launch the C8 Corvette.

In my wettest-dream fantasies I would buy a Mosler MT900, drop in a Mercury Marine SB4 engine and mate it to the C8's Tremec DCT.

In my modestly moist fantasy, I wait for a 2-3 year old C8 to hit the used lots, and then through the power of the aftermarket and some pretty serious DIY effort, I still drop in a Mercury Marine SB4 engine, strip out a bunch of weight...including the Global B electronic witchcraft, run the whole caboodle off an aftermarket ECU, and have myself a relatively affordable "exotic".

750 hp @8000rpm, 570 ft.lbs @5252rpm 

I figure with this engine, maybe a Dodson DCT clutch upgrade, Z06 or ZR1 suspension bits and a bunch of carbon fiber (homebrew and aftermarket), minus a bunch of interior crap and a metric crap-load of electrical nonsense, I'd have the American equivalent to the 458 Speciale or 488 Pista...for less than the cost of a house. 

GRM friendly? Likely not...an SB4 is a $30k engine. But a 2-3 year old C8 should trade for sub $45k...and I think $75k-ish for 750hp and a sub-3000 lb. curb weight (after the Colin Chapman/anti-Big Brother diet) would excite even the most jaded supercar owner.

What says the hive-mind? Would anybody here be interested in seeing the challenges, frustrations and problem-solving needed to bring such a creation to life? Is it too "rich" to be considered GRM? 

While there likely wouldn't be a lot of fabrication, there would be a ton of electrical integration, and trying to shove 10 lbs. of crap into a 5 lb. bag is always amusing to watch. 

I also recently acquired a small CNC mill that I would be using for some of the adaptors and novel ideas I've had for projects...could be a fun and interesting topic to eyeball for some of the readers.

 

aircooled
aircooled MegaDork
8/4/19 11:52 p.m.

You are not actually expecting anyone here not to encourage this sort of silliness are you?

Shine on you crazy diamond...

GarageGorilla
GarageGorilla New Reader
8/4/19 11:53 p.m.

In reply to Gingerbeardman :

Keep dreaming. The C8 ECU is going to tied into every module in the car. Everything in the car is going to be coded to that one specific ECU that came from the factory. In other words, it’s going to be a long time till someone does an engine swap on a C8, and that someone is not going to be some random dude in his garage, shoe horning a boat engine into a C8.

Gingerbeardman
Gingerbeardman Reader
8/5/19 12:06 a.m.
GarageGorilla said:

In reply to Gingerbeardman :

Keep dreaming. The C8 ECU is going to tied into every module in the car. Everything in the car is going to be coded to that one specific ECU that came from the factory. In other words, it’s going to be a long time till someone does an engine swap on a C8, and that someone is not going to be some random dude in his garage, shoe horning a boat engine into a C8.

Bosch Motorsport ABS is tuneable and available off-the-shelf.

Airbags can be dealt with or deleted.

Magneshocks already have aftermarket tuning and controllers available.

Tremec DCT will be cracked relatively quickly...AutoBionics in UK and COBB tuning already have PDK controllers available.

Mercury Marine SB4 is an automotive engine, not a boat engine, and comes with it's own ECU. At least a half-dozen companies offer aftermarket ECU's that could be swapped in it's place, offering traction control, launch control, power management, etc.

But I'm willing to take on the challenge...I already put in my order for an SB4 with the Roadster Shop. I was just wondering if anybody would be interested in watching the madness unfold.

Gingerbeardman
Gingerbeardman Reader
8/5/19 12:09 a.m.
aircooled said:

You are not actually expecting anyone here not to encourage this sort of silliness are you?

Shine on you crazy diamond...

Well, some shall-we-say parsimonious and curmudgeonly folks on here seem to be of the mind that only junkyard, horse-swaps and freebies are contenders for GRM builds...and then you have the other side, like the gentleman who rebuilt an AMG engine in his garage for 15% of what the factory wanted.

Not that anybody will sway me, I seem to be fairly stubborn once my mind is set, but why waste time taking photos and writing posts if no one wants to read about it?

mazdeuce - Seth
mazdeuce - Seth Mod Squad
8/5/19 4:31 a.m.

I'm just here to watch you disassemble a C8. That will be cool. Putting your motor back in will be even cooler. Do it!

MrJoshua
MrJoshua UltimaDork
8/5/19 5:04 a.m.

I will gladly read about it, but I will also ask why? By that time there will likely be a 750hp factory version of the Corvette. If not, that power level will likely be just a checkbook away and less than $30,000. At that point all you would need to do would be your lightweight fantasies which could be as simple or complicated as you want to make it. 

STM317
STM317 UltraDork
8/5/19 5:56 a.m.

Let me start by saying that I'm totally down for anything SB4, Roadster Shop, or C8 tear down. I also realize this is all speculating, but I'd be surprised if the SB4 would even fit in the C8 chassis without major rework.

I can't find dimensions for the new LT2, but the dry sump LT1 crate engine is about 26" wide at the cylinder heads

 

The SB4 is listed at 30.25" wide in their spec sheet:

 

Is a modern, mid engine car going to have 4-5" of unused wiggle room in the width of the engine bay? I'm guessing that LT2 is nestled in there pretty snugly with other stuff (including the cast aluminum cradle/shock towers) packaged as tightly as possible to keep the footprint small.

Don49
Don49 Dork
8/5/19 6:21 a.m.

I'm anxiously waiting for the build threaddevil

infinitenexus
infinitenexus Reader
8/5/19 6:27 a.m.

That engine sounds like pure secks.  I love it.  That being said, it would almost certainly be cheaper to just build the LT2 up to 750 horsepower, and you wouldn't have any fitment problems.  In a couple years we'll know the weak points of the engine, and Chevy will have released higher horsepower variants of it.  So I think it's very realistic that you could pull the engine, rebuild it with higher compression, a big cam, maybe a stroker kit, long tube headers, etc and wind up with 750 horsepower for half the price of the SB4.  It's already starting at just under 500, and you know in 6 months Chevy will come out with a 550hp+ version.  Then strip the interior down a bit, lose 1-200 pounds off the car, throw on some super wide tires and tweak the aero and you've got a super car.

infinitenexus
infinitenexus Reader
8/5/19 6:28 a.m.

Or I wonder how much it would cost to just get an Ultima GTR and put the SB4 in it?  That would be faster all around.

T.J.
T.J. MegaDork
8/5/19 6:40 a.m.

People here would definitely be interested in following along. If you end up dismantling a C8 as decribed, please post pics as you go.

Dusterbd13-michael
Dusterbd13-michael MegaDork
8/5/19 7:05 a.m.

z31maniac
z31maniac MegaDork
8/5/19 7:43 a.m.

Why the obsession with Mercury Marine engine? Just because it has DOHC heads?

HPR will build you an LSx small-block that will make that much power for far less. 

Ian F
Ian F MegaDork
8/5/19 7:55 a.m.

Given the recent history of GM Performance, once C8 production settles down into a solid rhythm there will likely be crate versions of whatever drivetrains become available for the C8 along with stand-alone ECU/DCT controllers. 

jfryjfry
jfryjfry Dork
8/5/19 8:50 a.m.

I get running stand-alone electronics for engine and abs, but you’d also be figuring them out for door handles and lights too.  Probably not insurmountable. 

But the transmission’s electronics might be. 

However, the answer already exists! (Although in a usable form, it might not....):

Manual! And this would be the greatest accomplishment of the project. 

dean1484
dean1484 MegaDork
8/5/19 5:31 p.m.

@OP. No where in the definition of Grassroots is a monetary value used to define it. 

What you are thinking is beyond cool. Go for it so we all can live vicariously through you. 

Indy-Guy
Indy-Guy UberDork
8/5/19 5:39 p.m.
dean1484 said:

@OP. No where in the definition of Grassroots is a monetary value used to define it. 

What you are thinking is beyond cool. Go for it so we all can live vicariously through you. 

This. I will very much read along. I think it's a very ambitious project, but I would love to follow along.

Gingerbeardman
Gingerbeardman Reader
8/5/19 7:36 p.m.
MrJoshua said:

I will gladly read about it, but I will also ask why? By that time there will likely be a 750hp factory version of the Corvette. If not, that power level will likely be just a checkbook away and less than $30,000. At that point all you would need to do would be your lightweight fantasies which could be as simple or complicated as you want to make it. 

If rumors are true, the top-dog C8 will be twin turbocharged...and while turbos are really cool, they heat-soak the engine bay and even with electronic techno-nannies, the torque really strains a gearbox.

A naturally aspirated "big-block" LS DOHC V8, the SB4 is essentially the modern incarnation of the LT5, and most Corvette nuts will tell you that that's the best engine ever placed between the Vette's framerails.

Unfortunately Mercury Marine refuses to sell just the heads & cams, or I could build a pretty stout version for less than $30k...there are a lot of super-mega-ultra high horsepower LS engines that cost less.

For whatever reason, the high-revving SB4 screams "supercar" to me, whereas as much as I love the LS platform, a lot of folks think it's just a low-tech "truck" engine with pushrods...in a way it's a subtle nod to exotic engines, while also a less subtle "up-yours" to all the LS-haters...because it's still an LS-based engine.

Gingerbeardman
Gingerbeardman Reader
8/5/19 7:40 p.m.

In reply to STM317 :

As I said above, I think it's going to be the proverbial 10lbs. of crap in a 5lb. sack...a few mm's here, a few mm's there, you can eek out space bit by bit.

Gingerbeardman
Gingerbeardman Reader
8/5/19 7:53 p.m.
infinitenexus said:

That engine sounds like pure secks.  I love it.  That being said, it would almost certainly be cheaper to just build the LT2 up to 750 horsepower, and you wouldn't have any fitment problems.  In a couple years we'll know the weak points of the engine, and Chevy will have released higher horsepower variants of it.  So I think it's very realistic that you could pull the engine, rebuild it with higher compression, a big cam, maybe a stroker kit, long tube headers, etc and wind up with 750 horsepower for half the price of the SB4.  It's already starting at just under 500, and you know in 6 months Chevy will come out with a 550hp+ version.  Then strip the interior down a bit, lose 1-200 pounds off the car, throw on some super wide tires and tweak the aero and you've got a super car.

Yeah, I totally get what you're saying...you're being reasonable...I'm being emotional. I've worked my ass off my entire adult life, saving and living below my means, taking care of family and my employers, stacking chips, being responsible, being reasonable, being SAFE and barely humoring my whims...I'm ready to have some fun and do something for ME.

For whatever reason, that engine, exotic cars and mid-engine platforms in general have always triggered the reptilian part of my brain like nothing else.

I had a health scare a year and a half ago, and even though I've had some close calls and lots of bodily damage, that was a wake-up call. Life is short. We're not guaranteed tomorrow. I want to enjoy some experiences before I get "too old" to indulge them.

I plan on keeping a car like this for the rest of my life...this will likely be the last "new" ICE car that I can indulge in that wouldn't require emptying my retirement accounts to afford.

I've been looking at doing some track stuff with a car like this...it would fit in several different classes at Bonneville, One-Lap would be cool, Hot Rod Power Tour, HPDE stuff, hill climb events, yada yada yada. I might never make it, but it beats driving a car that gets me from A to B with no soul and Walter-Mittying my way through life the way I've been doing for the last 15 years.

Call it a mid-life crisis, call it a boyhood fantasy, call it wasteful spending, call it what you will...for better or worse, it's captured my imagination after putting other "dreams" on the shelf.

It's the closest I'll likely ever come to putting a dent in the automotive-universe. A very minute, barely perceptible dent...but a dent nonetheless.

Gingerbeardman
Gingerbeardman Reader
8/5/19 7:55 p.m.

In reply to infinitenexus :

Yes, but the Ultima doesn't do it for me...and it's ridiculously overpriced for what you get. IMHO. I've helped assemble 3, along with 2 GT40 replicas, a GTM that I built, and a Locost that my buddy built. I'm kinda over the whole kit-car thing, honestly. 

Gingerbeardman
Gingerbeardman Reader
8/5/19 7:59 p.m.
z31maniac said:

Why the obsession with Mercury Marine engine? Just because it has DOHC heads?

HPR will build you an LSx small-block that will make that much power for far less. 

Pretty much...although it's a really understressed engine even at that horsepower level...valve lift is really mild. A 2 valve pushrod LSX or LT1/2/4 would be ragged-edge at that horsepower level.

I know they're capable, and though I'm not the "drive it around revved out in 2nd gear" type of guy, revving out that engine sounds SOOOO good...I actually got to ride in the passenger seat of the Ultima that was built for SEMA with the SB4...it's wild!

Gingerbeardman
Gingerbeardman Reader
8/5/19 8:00 p.m.
Ian F said:

Given the recent history of GM Performance, once C8 production settles down into a solid rhythm there will likely be crate versions of whatever drivetrains become available for the C8 along with stand-alone ECU/DCT controllers. 

One can only hope! I really do, because we could see some really cool projects with that kind of accessibility.

cbaclawski
cbaclawski New Reader
8/5/19 8:03 p.m.

Well, I'd love to watch this get done,  but 2-3 years from now just to get started is an awful long ways out for what is an if/maybe/want to...

I love DOHC 8's, in fact I have 2 (LT5 mentioned above and BMW s65)  I just don't know what you expect asking if people want to see pic's IN 3 YEARS! 

 

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