Opel GT Forum banner

1 - 20 of 131 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #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
 

·
Just Some Dude in Jersey
Joined
·
14,300 Posts
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.
 

·
Banned
Joined
·
420 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #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
 

·
Just Some Dude in Jersey
Joined
·
14,300 Posts
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......
 

·
Registered
Joined
·
3,088 Posts
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.
 

·
Opelitis afflicted
Joined
·
530 Posts
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.
 

·
Registered
Joined
·
56 Posts
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!
 

·
Registered
Joined
·
145 Posts
3.4 swap

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.
The 3.4L has a lot of potential and with the upgrade to 3400 or 3500 heads and intake you can push 200 hp.

http://www.s10forum.com/forum/gtsearch.php?cx=partner-pub-7865546952023728:za13gk-qi81&cof=FORID:11&ie=UTF-8&q=3500+head+swap&sa=Search&siteurl=www.s10forum.com/forum/60v6-forum-2-8-3-4/
 

·
Member
Joined
·
1,175 Posts
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.
This can be done without cutting? I guess you need new motor mounts, new drive shaft. What modifications are required to fit the matching manual transmission? 5 speed possible? What are some of the things you need to plan for for this motor swap?
 

·
Registered
Joined
·
1 Posts
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.
 

·
Registered
Joined
·
207 Posts
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.
 

·
boomerang opeler
Joined
·
5,629 Posts
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 :)
 

·
Member
Joined
·
789 Posts
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.

.
A Weekend...WOW! Ron Deloziers(RIP) 3.1L V6 took him years!
 
  • Like
Reactions: wankelgt

·
Registered
Joined
·
1,494 Posts
I love to read of all these wonderfull conversion ideas.
But does anyone know what kind of torque the chassis is designed for?
Prototype Opel GT's were tested on the track with a 128HP 4-cylinder motor in 1967.

Larger engines can be installed but they will have adverse effects on the handling, as there are no available upgrades for the front suspension, the steering shaft has to be articulated with u-joints to clear exhaust manifolds in the engine bay, and cut-down rear axles are heavier than the stock differential.
 

·
Registered
Joined
·
602 Posts
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.
 
  • Like
Reactions: RallyBob

·
Über Genius
Joined
·
8,938 Posts
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.
 

·
Registered
Joined
·
602 Posts
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.
 

Attachments

1 - 20 of 131 Posts
Top