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List of best engine swaps?

162K views 140 replies 58 participants last post by  Justion337 
#1 ·
I want to get started restoring my 73 GT. I'm just not excited about the original engine. I want to do a engine swap but I'm just can't decide what to put in it. I have a T5-trans. I thought of a Quad 4 or a Ecotec. Is there information on these swaps or others? No V-8s please. I think the V8 is way too heavy for the car. I'm a road racer and would like to be able to take the car out for some laps. I'll be updating the axles and brakes too. I love the styling of the car just no its mechanics.
thanks Leebo
 
#2 · (Edited)
Putting one of those Grand National 6 bangers seems to be a popular swap that works and looks good. But for that kind of money you could jack up the stock-style of engine to 150-200hp and everything will fit and there'll be minimal slicing and dicing of the car. Don't forget, you've got the low 60hp engine in a 73. Earlier ones had 90hp engine. Think how much more you'd like your car if it was just 50% more powerful. Now start thinking about doubling your hp and having reliable fuel injection. I already kick the butt of most cars on the road at just 110 or so hp.

Use the search feature to find posts on Mazda/rotary, ecotec, or any other engine you can think of. There's a great thread on going electric.
 
#4 ·
I prefer the one word list:
WANKEL.
 
#5 ·
I've got 3 gt's two of them are 70s with a 1.9. How much horsepower could I get out of one of these without burning money. I've got a vette that weighs 3000lbs and has 330hp. Its very fun on the track with this power to weight ratio. I've never weighed the opels and don't know what they weighed stock? If I could get 1 horsepower for every ten lbs I would be happy.

So, I guess the real question is, is it more economical to build the 1.9 for this hp or engine swap? I'm quessing stripped down the GT would be around 2000lbs so 200hp would be awesome.

What do you guys think?
thanks for your input.
Leebo
 
#8 ·
So, I guess the real question is, is it more economical to build the 1.9 for this hp or engine swap? I'm quessing stripped down the GT would be around 2000lbs so 200hp would be awesome.

What do you guys think?
thanks for your input.
Leebo
After installing many engines on GTs over the years, the absolute best I have found is a 3.4L V6 tuned to 180HP. Best of all is that it can be done in one weekend.

I had a 3.8L in a '72 GT but it was too much HP and you lost control of the car very easy.

Some of my V6 cars should be in the archives.
 
#6 ·
I'm barely knowlegable, hopefully others will fill in the blanks or you can search the numerous threads on 2.2L-2.4+L engines. Stock GT's weigh about 2100lbs.

Pretty maxed out, an Opel 2.4 engine could come close to the 200hp, although normally they're about 160hp or thereabouts. You'll have to upgrade the tranny and clutch to a Getrag 5 speed or use an automatic. I think there's an American manual tranny or two that you can adapt. The rear will have to be upgraded. There's a mod to use a cut down 6 cyl Opel FI manifold for more performance. One of our members, Opelspyder, installed a Weber FI system that I think they worked together a bit on. Side draft Webers for possibly more power. At this point my knowledge is sparse......
 
#9 ·
I would be thinking Saab 2ltr or 2.3ltr turbo with a BMW E30 rear end if I was going down the engine swap route. Hood clearance might an issue though and I would prefer not to have to put a bulge in. Maybe some day.
 
#10 ·
I love to read of all these wonderfull conversion ideas.
But does anyone know what kind of torque the chassis is designed for?

Opel has a recommended max torque for the Ascona/Manta A-model of around 240 - 250 nm, it will probably be something equal for the GT.

The rearaxle is strechted to the limits with torque around the same. Thats the main reason for using a six-cylinder axle on the 400!

The Getrag 240 is laid out to a maximum of 240 nm - hence the name!
 
#14 ·
I love to read of all these wonderfull conversion ideas.
But does anyone know what kind of torque the chassis is designed for?

Opel has a recommended max torque for the Ascona/Manta A-model of around 240 - 250 nm, it will probably be something equal for the GT.

The Getrag 240 is laid out to a maximum of 240 nm - hence the name!
220nm for the GT, do you have any documentation for the 240-250 for the ascona/manta a?

I thought it was 240lbft.
 
#13 ·
I'm working on installing the 4g63 turbo engine from an eclipse/talon in my 70 gt. Great engine platform and there are numerous trans options for rwd operation. The one going in mine has somewhere around 700hp with the turbo on it now. Like to go bigger in the Opel. I am also partial to the 2.4L turbo neon motor since I have an srt-4. I've never had the valve cover off the engine at almost 95,000 miles and around half of those miles have been at 400-420whp with the larger turbocharger and bolt-ons.
 
#15 · (Edited)
not V8's of which a few have been done to no ill effect but

jaguar straight 6 cylinder with 4speed and over drive goes in nice to the GT but is a little heavy for the stock front end so i used the jag front end and the rear cage mounts easy to the GT

also the V12 jag goes in nice but to make it easy i was using the whole floor of the jag with all the running gear with the GT body welded on to it . only 6" difference in wheelbase so easy to work round when fitting arch flair kit

BMW 6 cylinder engines the one i had in was a 2800

many Ford 4 cylinder engines , a whole host of GM 4 cylinder engines from europe


never discount something just because you cant see a way of doing it :yup: all it comes down to is money and any thing can be done :)
 
#18 ·
IMO any engine swap is a good one as long as it doesn't upset the balance of the car, over stress the chassis, require hacking up the body and most importantly ends up looking like it belongs there.
 
#19 ·
I know of a guy who put a 200? four banger in his GT. It was pretty squished under the hood but he said he only had to cut a couple inches for something.
It was from a newer RWD car but he said he even used the original cross members.

I wish I could remember what it was out of. I want to say a Toy.
 
#20 ·
My Zetec install required removal of the stock throttle bracket on the left footwell for header clearance and a 1/2" dimple in the right fender well for extra clearance on one of the AC fittings. I removed the stock air filter bracket and radiator mount brackets for a cleaner look but it wasn't necessary for the install.
 

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#21 ·
Where does one get a Zetec? What tranny is with it?
 
#27 ·
I'd like to see some more pictures of that Ztec installation. It looks very clean. I have a SR20DET (207 hp) in my GT which is also twin cam, but it looks like you've got a lot more room around your engine. I'm always looking for improvement ideas.
 
#28 ·
Anyone ever look at the L61 motor for a swap. It is a decendent to our Opel motors and were installed in Saturns.
 
#29 ·
Here are a few more pics.
 

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#31 ·
Looks great Ron, very clean.
What are you running for a master cylinder? No power assist?

Pat
 
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#32 ·
Running factory M/C What you see in the pics is the M/C for the hydraulic clutch.
 
#35 ·
To each their own and I respect that. My goal was never to have a quirky high HP car. It is to have a reliable and comfortable Opel I can enjoy driving anywhere. Just like some of my other mods, I knew when I did this swap a lot of people wouldn't like it. However I am the only person I have to please and I picked the Zetec for many reasons. It's modern, affordable, plentiful, makes 130 HP in stock form, it's raced all over the world so performance parts are everywhere, lighter and smoother then the opel engine, it is a very easy engine to work on and most importantly it fits without hacking the car. The hardest part of the swap was building the header. That took about 30 hours. But if a person was looking for lots of power and didn't want AC, as short as the engine is, a front mounted turbo setup would be a breeze.
 
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#34 · (Edited)
To: heliman
If you did that install and all the R & D yourself, You are the MAN!!!!!:yup:
 
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#37 ·
I know it must sound that way and with my upcoming rear end swap I will have a complete Ford drivetrain. But in all honesty I'm not a Ford guy either! It was just what I believed to be the best and easiest swap to acheive what I was looking for. All said and done I couldn't be happier with it. So for me, the goal was met.
 
#38 ·
Beyond the engine swap is the carbon fiber work on the door panels and center console. Which are totally outstanding. The custom made fiberglass dash that you can not tell is not factory original. "mind blowing". And last but not least the complete digital dash with custom center panel. and the built in a/c. Es ist unglaublich :yup:

Ron your were suppose to come to Springfield this year we missed you.

Your the man RON

An other SWMO car builder goes over the top/

Madmann
 
#39 ·
Thanks Mike, hopefully next year we'll make Springfield. Are you guys coming up here for the Street Machine nationals this weekend? It would be nice to have a big Opel showing!
 
#41 ·
How to do it best.



The absolute best choice is a Cosworth. Strangely enough, you can buy a complete car in UK, the Fords, for less than an engine will cost you in the US. The other option is the Mercedes Cosworth. The come up often on Ebay and reasonably priced too. Strip off all the garbage and FI, add carbs and no electronic gadgets and fly like the wind. Parts are readily available for this. Dont buy from Mercedes, buy from aftermarket mfrs and save lots of $$.
 
#42 ·
The 2.0 Ecoboost turbo in my 2013 Focus ST would be awesome in a GT, but I have no idea of the work involved. It's about the same weight as the Opel 1.9, but with 252 hp & 270 lb·ft at just 2,500 rpm, it would definitely scoot.

Maybe I should buy a 2nd GT and try that myself!
 
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#44 ·
While that sounds very interesting I would probably have gone with a 1.0 Ecoboost myself, 3 cylinder, 125 hp and much lighter than the stock engine. That way you'd get back the weight balance of the 1.1 but have better performance than a 1.9.

Not that I would ever put a Ford engine in my Opel of course
 
#46 ·
The Zetec is about 3 inches shorter then the Opel engine, but sits an inch further forward then stock at the bellhousing. So I still ended up with 2 extra inches of clearance. I would of had plenty of room for a stock or Honda radiator, but I'm using a larger early Mustang radiator that would not fit in the original location. It also allows a better placement for my A/C condenser.
 
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