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Discussion Starter · #1 · (Edited)
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HI all,

I purchased a blue opel and the motor did seize right after purchase. I was planning to do a swap, but in a couple years. Life changed my plans, so I'm going for it.

Fun Fact

"This 2.3 ecoboost is a stroker version of the 2.0 ecotec block in the newer opel Gt in Europe or saturn sky redline in the U.S.A." In a way this is a Opel GT motor... kind of haha

No better time then the present with Covid!

I purchased a 2019 6 speed mustang from Co-part, and pulled the drivetrain from the opel.

This theoretically will be amazing @ 2000 lbs in my mind. Direct injection and low weight should deliver 40 mpg and 350 ft/tq 350hp. Wide body will be fun to build as well with fiberglass.

16k in, wish me luck!

I'll tell you when i hit $25k.


-Taylor
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Your Noble Friend ;-)
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This engine will rip the GT into shreds.

Dieter
 
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I'm interested how you will make this independent rear suspension work.
 

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Detritus Maximus
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My thought?....if that blue GT is your car with a dead motor, order a rebuild from GT Source and then sell the car. It's too nice to cut up to fit the Mustang drivetrain. Buy a rusty GT for much less money and start building a full tubeframe chassis to handle the Mustang components. Massive amounts of engineering and money will be needed to make this work, but it would make for a neat project if done right.

If this is real.
 

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Discussion Starter · #7 · (Edited)
I'm interested how you will make this independent rear suspension work.

I'll add pictures as I figure it out. If I can't do it without ruining the chassis, I'll change my plans.

I bought the crashed car for its engine, transmission, ecu, harness, and differential.

If I can use anything else like the brakes or the suspension it's just a bonus. A bonus that I want to make work at least for the rear end. The front end may need some sort of mustang 2 dropin double wishbone front suspension.

I'll know once I have it all in front of me.
 

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Discussion Starter · #8 · (Edited)
My thought?....if that blue GT is your car with a dead motor, order a rebuild from GT Source and then sell the car. It's too nice to cut up to fit the Mustang drivetrain. Buy a rusty GT for much less money and start building a full tubeframe chassis to handle the Mustang components. Massive amounts of engineering and money will be needed to make this work, but it would make for a neat project if done right.

If this is real.

This is real, but I do like this blue opel. I paid 5k for her. She told me that she wanted to be a lot faster in the time I had with her.

I will figure it out as I go, I always do!
 

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#Heliman #Rallybob

People I need to tell me I'm crazy, but give me good advice anyway.
Looking at the track width difference (not factoring in wheels and tires), the IRS is nearly 15” wider. Call it 21” with a decent wheel and tire fitted. I wonder if the suspension pickup points will even stay under the Opel chassis?

You’ll end up cutting out a bunch under the hood and the tranny tunnel to fit the bigger engine and gearbox. You’ll cut the entire rear floor pan out to fit the IRS. The front suspension....totally depends which direction you go with.

It may be easier to retain the Mustang floor pan, shorten it to match the Opel’s wheelbase (by about 11”), cut the GT body off it’s floorpan, then fit the GT upper body to the Mustang floorpan.

Then, flare the fenders to cover the new wheels and tires. About 10.5” per fender based on the numbers I’ve seen. You’ll probably need to flare the rocker panels too, to mate with the floorpan.

I think it will be the easiest way to go
 

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10.5" fender flare PER SIDE! Lol.

She's going to look like she prolapsed out the sides from pushing too hard when squatting.

A shame you're doing this to a $5000 GT. My $200 GT already had the trans tunnel cut out for you and the rough-ish shape of the rest of it really wouldn't have caused you any trouble you're not going to go through anyway.

Do what you want with your own property, no judgment, but I think you've paid for a lot of value in a car just to remove that value by chopping it back to equivalent to something you could've picked up for less. Might want to save $4000 and throw that into some other part of it.
 

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Detritus Maximus
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This is real, but I do like this blue opel. I paid 5k for her. She told me that she wanted to be a lot faster in the time I had with her.

I will figure it out as I go, I always do!
Yeah, they always say that, don't they? There's been several new members lately with the 'what other motors will swap'' question. Many of them go nowhere because it's not a Honda or Nissan or they start cutting and give up, ruining a previously good car. My thoughts are based on how much of the niceness of the blue GT will need to be undone and then redone to achieve your goal.

RallyBob is the guy to listen to as far as what is needed or doable. The more of the Mustang components you keep, the more dynamically balanced the car will be with less reinvention of the wheel.

On a related note...

Over 500hp Volvo in an Opel Manta A



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I would suggest you look up a thread from one of our WI members who goes by ( broszzy ) titled MY Boy. This is his effort to put a 2.3L Ford and a narrowed Jag independent rear in GT. Not sure if he finished but shows a lot of pictures of the build.
 

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Opeler
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I think that motor and tranny combo with a LSD would be awesome and I agree with the sentiments that have been given by Rally Bob and others. Modifying the Mustang floor pan and then grafting the Opel body would be the easiest way to accomplish the full swap that you describe. Keeping the Mustang track width with the Opel body may end up with an excessive wide body look. Instead of adding all of the additional width with fender flares you could section the body down the middle and widen the whole body by 8 or 10 inches. This will make it fit better on the Mustang floor plan and still allow for large proportional looking fender flares. But it will likely end up weighing quite a bit more than 2000 lbs. I echo the other sentiment that if you are going to do this much cutting you should buy a lower cost less complete GT to cut up and keep the blue one intact for it's original charm or sell it to fund some of the Frankenstein beast.

If you're really set on putting the Mustang motor into this blue GT I would scale back the idea of using the full Mustang IRS. There are other IRS options such as Miata, 3 series BMW, or S13 that would be a closer fit to the GT. Or you could use the Mustang diff and design your own control arms based on Miata or a Locost design. You may even be able to install the Mustang diff into the Miata suspension with shortened half shafts.

Another option could be to use a Ford 8.8 rear axle out of an Explorer and fab up a 3 link suspension. Custom front control arms and reinforced cross member would take care of adding width to the front to match the Explorer rear axle.
Either way you'll want to add some significant sub-frame connectors and chassis reinforcement.

When I swapped in the SR20DET engine and tranny into my 71GT one of my goals was not to cut anything up too much that it would be hard to return to stock in the future if someone decided to. I removed a bit of material in the foot wells to accommodate the manifolds. If I chose to bolt the original engine back in the only thing that I would need to do is convert to a cable operated throttle since I removed the sheet metal that supports the throttle linkage.

Lastly spend some time looking at pictures of Heliman's car. He did a very nice job on his swap and still kept all the charm of the GT.
 

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Discussion Starter · #15 · (Edited)
I asked Heliman to help me haha I saw his beautiful build. His car is like a piece of art, I first found his build by finding the car for sale.

I want to retain the perfect weight ratio of the opel gt for handling in forward motion. 51% front and 49% rear

I need to improve it's suspension to modern suspension though I think. I desire a much wider track width for higher speed turning.

I know the car has amazing aero dynamics for traction at high speeds as it is. The beautiful body lines are actually an aero package that gives it downforce at high speeds.


Technically I could tune this motor to not rip the stock spec gt to shreds by reducing low end torque. I would probably have to swap the twin scroll turbo charger and slightly detune it. It does weigh less then the original motor so it wouldn't stress the stock suspension.

The one problem is my new motor at the top is 23" in width. The stock motor is 17" because the intake and exhaust are on the same side as you know. Height and length are basically the same. It is about an inch and a half shorter in length.
 

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Discussion Starter · #16 · (Edited)
Yeah, they always say that, don't they? There's been several new members lately with the 'what other motors will swap'' question. Many of them go nowhere because it's not a Honda or Nissan or they start cutting and give up, ruining a previously good car. My thoughts are based on how much of the niceness of the blue GT will need to be undone and then redone to achieve your goal.

RallyBob is the guy to listen to as far as what is needed or doable. The more of the Mustang components you keep, the more dynamically balanced the car will be with less reinvention of the wheel.

On a related note...

Over 500hp Volvo in an Opel Manta A



View attachment 429145

Now that is a beautiful car with no expense spared on its attention to detail.

Did you reduce the overall weight of the car by doing a custom tube front end?

What custom suspension did you decide to go with?
 

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Opeler
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The one problem is my new motor at the top is 23" in width. The stock motor is 17" because the intake and exhaust are on the same side as you know. Height and length are basically the same. It is about an inch and a half shorter in length.
The SR is much wider than the stock engine also. The biggest problem with the width was the turbo and finding a space to run the exhaust pipe down from the turbo to under the car. Another thing to look at is the size and length of the transmission. The opel trans is very small and very short, and the trans tunnel tappers down quickly. Other transmissions are much longer longer. I had to clearance the back of the trans tunnel with a sledge to get the nissan tranny to fit and even then there is not much clearance between the front u-joint on the driveshaft and the back of the tunnel.
 

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Discussion Starter · #19 · (Edited)
Looking at the track width difference (not factoring in wheels and tires), the IRS is nearly 15” wider. Call it 21” with a decent wheel and tire fitted. I wonder if the suspension pickup points will even stay under the Opel chassis?

You’ll end up cutting out a bunch under the hood and the tranny tunnel to fit the bigger engine and gearbox. You’ll cut the entire rear floor pan out to fit the IRS. The front suspension....totally depends which direction you go with.

It may be easier to retain the Mustang floor pan, shorten it to match the Opel’s wheelbase (by about 11”), cut the GT body off it’s floorpan, then fit the GT upper body to the Mustang floorpan.

Then, flare the fenders to cover the new wheels and tires. About 10.5” per fender based on the numbers I’ve seen. You’ll probably need to flare the rocker panels too, to mate with the floorpan.

I think it will be the easiest way to go

I don't technically want to cut anything if I don't have to for optimal performance. I do need fully customizable/adjustable suspension though. I love the design and unibody strength. It is handmade, and a work of art.

I just want to modernize the drivetrain and make it handle amazing... That's it haha. The idea is a truly reliable and efficient modern power source combined with the light weight perfection and exceptional beauty of this old car.
 

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Discussion Starter · #20 · (Edited)
The SR is much wider than the stock engine also. The biggest problem with the width was the turbo and finding a space to run the exhaust pipe down from the turbo to under the car. Another thing to look at is the size and length of the transmission. The opel trans is very small and very short, and the trans tunnel tappers down quickly. Other transmissions are much longer longer. I had to clearance the back of the trans tunnel with a sledge to get the nissan tranny to fit and even then there is not much clearance between the front u-joint on the driveshaft and the back of the tunnel.

So this motor is very efficiently condenced. I can purchase a top mount intake setup for about 200$. This would land the turbo perfectly where that little bubble feature of the hood is that makes the opel gt so unique.


Update-(It's definitely heavier, I was what one might call super wrong)
 
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