128 HP Dual Carb Opel GT?

rocknroll · 11-22-2005

The original Opel GT's featured 15-inch wheels, front and rear anti-sway bars, and a 128hp dual-carburetor "Sprint" engine, before it was "de-tuned" by GM for the US market. Production models did retain the original 150mph speedometer, which is synchronized to maintain a parallel needle position with the functional tachometer at speed.

I got this info from opelgtclub.com.... were these 128hp gts in production? ..if so they were prob dam fast

Motor Mouth · 11-23-2005

I think we're talking about the 'Experimental'......I never thought it had 15" wheels and the pics I have show the engine in a 'cross-flow' configuration although that said this did run a twin-carb system.

The original production models, '68 onwards ran 102hp for the European market, then as we know US emissions dictated a decrease until in '73, just before production ended, I think the GT was putting out about 75hp......not much more than the original 1.1.

asdasc · 11-23-2005

Very cool! Do you have any pictures of the dual carb cross flow configuration? I have always liked the way the tach and speedo are sync'd but didn't realize it was intentional. Why did GM de-tune it? Did they think Americans would prefer less power?

Another thing I have always liked is the non-linear fuel gage. It gives you much better resolution where you need it, toward the bottom of the tank!

kwilford · 11-23-2005

Here is one I have at the office. I will see if I have better ones at home tonight

GTJIM · 11-23-2005

Here is an article about the Experimental GT - with a pic of the cross-flow motor.
Looks like it was fuel injected with individual inlets for each cylinder - Wow!

asdasc · 11-23-2005

Wow! Great article. I wonder why they trimmed 25HP from the engine prior to shipping over here? Obviously, the lower compression for the common grades of fuel and maybe more reliability? Probably the Solex was a huge cost save. Notice the intake is on the drivers side of the head. With a head like that, you could add the dual DCOE's without moving the heater box!

GTJIM · 11-23-2005

The motor in the Exp. GT was a hand-built special made to push that car to 140mph for "suspension testing" at Opel's Test Track in Germany.
The eventual 1.9L/Solex motor used for production was the standard motor which was already in use for the Kadetts of the time. I guess the they thought it gave quite enough "performance" at the time and it was available in quantity from existing production.
There were, possibly, plans in place to use the Record "Sprint" motor which had twin downdraft DCNO Webers and a "Sprint" exhaust manifold - but it would have meant a bigger bonnet buldge to fit the carbs.

Motor Mouth · 11-23-2005

Well done Jim, I knew you had to have something on hand. The only bizarre thing now is that the Conrero GT is crossflow design yet the carbs are passenger side of the engine bay, haven't got any pics to hand at present but will see if our Chairman can fire one down when he's next out in the garage.

jeff denton · 11-23-2005

That is wild! I wish the small print were readable on my screen. I just have to know what cylinder head that is.

Motor Mouth · 11-24-2005

Jeff,

You'll find a couple of articles on the experimental in the Brooklands book called Opel GT, they then did a later one call Opel GT Gold Portfolio......what's more you can read about my car too

asdasc · 11-24-2005

Hey, I have that book!! The GOld Portfolio! I haven't looked at it in a long time, now I will have to. Which car is yours?

Motor Mouth · 11-24-2005

I was going to say mine's the red one with the fawn interior, featuring the 1.9 Fuel Injected engine with the black rocker cover.......but then I remembered the books in black and white.

The article is in the back of the book, can't remember the page number.....but it's called 'Drag Act', you can spot the black rocker cover and the vehicle reg is HUM 138G. The reason the car's in there is because the car was once owned by the Team Manager, Tony Fall, of Dealer Opel Team.....I won't go on with the rest of the story, so you can savour the read over a Bud.

asdasc · 11-24-2005

I found it! Very nice!

I chose to savor it over a Guinness, out of respect.

GTJIM · 11-25-2005

Originally Posted by asdasc

I found it! Very nice!

I chose to savor it over a Guinness, out of respect.

Try a German Beer!

tekenaar · 11-25-2005

Originally Posted by GTJIM

Try a German Beer!

Better with a Pauli girl . . .

tekenaar · 11-25-2005

Originally Posted by GTJIM

Here is an article about the Experimental GT - with a pic of the cross-flow motor.
Looks like it was fuel injected with individual inlets for each cylinder - Wow!

Ah, memories! That looks the same as the head that was offered by More Opel in WA in the late '70s . . . still have one of their catalogs here somewhere.

tekenaar · 11-25-2005

Originally Posted by kwilford

Here is one I have at the office. I will see if I have better ones at home tonight

That looks like a 1.1 OHV engine to me . . . definitely non-crossflow

Gary · 11-25-2005

Originally Posted by GTJIM

Here is an article about the Experimental GT - with a pic of the cross-flow motor.
Looks like it was fuel injected with individual inlets for each cylinder - Wow!

Jim - .PDF or .SWF files can be uploaded to the Articles section. That would make a great read and maybe kick off similar uploads.

tekenaar · 11-25-2005

Originally Posted by jeff denton

That is wild! I wish the small print were readable on my screen. I just have to know what cylinder head that is.

Jeff, the pic is probably 'autosized' in your browser. Hover cursor over lower right of pic and an orange 'lozenge' with four arrows at the corners will appear there. Click on it for 'full size' view of image. HTH

kwilford · 11-25-2005

Originally Posted by tekenaar

That looks like a 1.1 OHV engine to me . . . definitely non-crossflow

The air filter sure looks like the 1.1, but it is DEFINITELY the Experimental GT from 1965. I wonder if they had a 1.1 for display, and the cross-flow for performance testing.

11-22-2005	#1 (permalink)
rocknroll Opeler Join Date: Oct 2005 Location: New Jersey Posts: 46 Classified Rating: 0% (0)	128 HP Dual Carb Opel GT? The original Opel GT's featured 15-inch wheels, front and rear anti-sway bars, and a 128hp dual-carburetor "Sprint" engine, before it was "de-tuned" by GM for the US market. Production models did retain the original 150mph speedometer, which is synchronized to maintain a parallel needle position with the functional tachometer at speed. I got this info from opelgtclub.com.... were these 128hp gts in production? ..if so they were prob dam fast

11-23-2005	#2 (permalink)
Motor Mouth 'NO,......O P E L..G T!' Join Date: Jul 2003 Location: Lincoln, UK Posts: 516 Classified Rating: 0% (0)	I think we're talking about the 'Experimental'......I never thought it had 15" wheels and the pics I have show the engine in a 'cross-flow' configuration although that said this did run a twin-carb system. The original production models, '68 onwards ran 102hp for the European market, then as we know US emissions dictated a decrease until in '73, just before production ended, I think the GT was putting out about 75hp......not much more than the original 1.1.

11-23-2005	#3 (permalink)
asdasc Senior Contributor Join Date: Oct 2005 Location: Mt. Clemens, Michigan Posts: 888 Classified Rating: 0% (0)	Very cool! Do you have any pictures of the dual carb cross flow configuration? I have always liked the way the tach and speedo are sync'd but didn't realize it was intentional. Why did GM de-tune it? Did they think Americans would prefer less power? Another thing I have always liked is the non-linear fuel gage. It gives you much better resolution where you need it, toward the bottom of the tank!

11-23-2005	#6 (permalink)
asdasc Senior Contributor Join Date: Oct 2005 Location: Mt. Clemens, Michigan Posts: 888 Classified Rating: 0% (0)	Wow! Great article. I wonder why they trimmed 25HP from the engine prior to shipping over here? Obviously, the lower compression for the common grades of fuel and maybe more reliability? Probably the Solex was a huge cost save. Notice the intake is on the drivers side of the head. With a head like that, you could add the dual DCOE's without moving the heater box!

11-23-2005	#8 (permalink)
Motor Mouth 'NO,......O P E L..G T!' Join Date: Jul 2003 Location: Lincoln, UK Posts: 516 Classified Rating: 0% (0)	Well done Jim, I knew you had to have something on hand. The only bizarre thing now is that the Conrero GT is crossflow design yet the carbs are passenger side of the engine bay, haven't got any pics to hand at present but will see if our Chairman can fire one down when he's next out in the garage.

11-23-2005	#9 (permalink)
jeff denton former opel racer Join Date: Nov 2002 Location: near some glaciers Posts: 2,774 Classified Rating: 0% (0)	That is wild! I wish the small print were readable on my screen. I just have to know what cylinder head that is.

11-24-2005	#10 (permalink)
Motor Mouth 'NO,......O P E L..G T!' Join Date: Jul 2003 Location: Lincoln, UK Posts: 516 Classified Rating: 0% (0)	Jeff, You'll find a couple of articles on the experimental in the Brooklands book called Opel GT, they then did a later one call Opel GT Gold Portfolio......what's more you can read about my car too

11-24-2005	#11 (permalink)
asdasc Senior Contributor Join Date: Oct 2005 Location: Mt. Clemens, Michigan Posts: 888 Classified Rating: 0% (0)	Hey, I have that book!! The GOld Portfolio! I haven't looked at it in a long time, now I will have to. Which car is yours?

11-24-2005	#12 (permalink)
Motor Mouth 'NO,......O P E L..G T!' Join Date: Jul 2003 Location: Lincoln, UK Posts: 516 Classified Rating: 0% (0)	I was going to say mine's the red one with the fawn interior, featuring the 1.9 Fuel Injected engine with the black rocker cover.......but then I remembered the books in black and white. The article is in the back of the book, can't remember the page number.....but it's called 'Drag Act', you can spot the black rocker cover and the vehicle reg is HUM 138G. The reason the car's in there is because the car was once owned by the Team Manager, Tony Fall, of Dealer Opel Team.....I won't go on with the rest of the story, so you can savour the read over a Bud.

11-24-2005	#13 (permalink)
asdasc Senior Contributor Join Date: Oct 2005 Location: Mt. Clemens, Michigan Posts: 888 Classified Rating: 0% (0)	I found it! Very nice! I chose to savor it over a Guinness, out of respect.