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Discussion Starter · #1 ·
Time to welcome a new addition to my little Opel family. A couple weeks ago I made a short trek north to pick up a ’69 Opel 1.1Litre GT sans motor – Thank you Edwin. The trip in itself was an adventure, but that’s another story. Anyway, I would like to restore it back to a reasonable facsimile of original including the 1.1 Litre engine.
Here comes the interesting/obscure part. I seem to recall hearing that the 1.1 Litre GTs were used in racing due to their lighter weight. And that they were reasonably quick cars after the engine was built to around 100HP. Can anyone confirm this? And what was done, and what can be done, to pull an honest 100HP of reliable power from the 1.1?
I have been considering using a 1.2 Litre engine from Europe with an 80mm bore, welding/offset grinding the crankshaft by 8mm, and using small journal connecting rod (maybe from a Nissan, Honda, or MC with a 1.557 journal diameter) to increase the stroke from 61mm to 74mm. This would increase the displacement from 1196cc to 1488cc effectively giving me a 1.5 Litre engine.
I would welcome any thoughts/questions/comments/problems etc. that anyone one can think of, or if anyone might have a better method I would appreciate hear the input.

Darrin
 

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It'll take a LOT of money and know-how to pull an honest 100 hp from a 1.1 litre. A larger displacement engine would make it easier, but with a 3- main bearing crankshaft, I wouldn't get too carried away there either. You'll need a substantial amount of headwork, a custom cam, valve springs, retainers, pushrods and intake and exhaust system (stock won't do). Years ago this stuff was available off the shelf, but nowadays......

May as well put a Hayabusa engine in the car....175 hp and almost no weight.....

Bob
 

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I figure there aren't many 1.1s left, which is the reason I at least wanted to make it appear stock. What would be a good recommendation of what I could reasonably do?

Darrin
 

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It'll take a LOT of money and know-how to pull an honest 100 hp from a 1.1 litre.
Ha! It's taken me a lot of money and know-how just to get one of these engines to pull the STOCK 50 hp! I've had a hell of a time finding stuff...my rebuild started in February this year, and all of the delays have been due to trying to find OEM parts (except had to use a couple BMW valvetrain parts). Engine overhaul pieces are scarce even in Germany.... especially since model 93s have the US-spec 1100SR engines (cam differences, for example).

If you want to keep the SAME light handling feel but with lots more power, go with a rotary conversion. If you decide to put a 1.1L back in, I'd recommend getting a 1.2L or standard 1.1L. As I've learned, the US-spec SR engine was produced in small numbers, and factory parts are hard to come by. Just to get one running again, you may need to machine/adapt. Standard 1.1 parts are probably more available.

In terms of a "performance" upgrade, I've heard that the dual carb setup isn't too efficient. Steinmetz or Irmscher made a single sidedraft weber manifold for the 1.1L a long time ago... but good luck trying to find of those! (I'll post a pic when I find it.)

Anyway, congratulations on your new acquisition, Darrin! I think you'll find it challenging and rewarding (in an oddball sort of way).

Walter
 

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all you had to do is ask

I'm pretty sure I have a couple of sets of bearings, maybe some valves, possibly a set of pistons, and more gaskets for the 1.1 than you could possibly want.

I used to have a pretty cool 1.1 header and awesome intake for the 1.1. The intake manifold allowed for a single IDT style Weber carb. It was so easy to tune, and that style Weber is available all the way up to dual 44mm throttle bores!

That silly Kadett sedan was the fastest stop light to stop light car I have ever driven. Of course with the 4.11 rear end it topped out at 72mph at 6400rpm, but it was darn quick to get there! The 43mpg was pretty cool too.

I wish I knew what happened to that car now.
 

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Maybe I was a bit too ambitious. I should probably start with what is important to me.

1)Origionality. I would like to keep an engine that was originally in the same series in the car, and maintain an origional LOOK even if it was not an OEM piece.

2) Balance. I would like the car to feel balanced and well behaved. If that means sway bars, then sway bars it is, even if they weren't OEM.

3)Power. The 100HP mark was just taken from something I had heard once a long time ago. I am not enamoured with a specific number. The goal here is just to make it quicker than stock. I won't be racing it, so, anything that can be accomplished for a reasonable amount of money is fair game.

Now for the specifics: I have a bare block that doesn't look it will be servicable, also the crankshaft (the bearing surfaces are badly rusted), one connecting rod and piston ( that are seized together). So I will probably looking for another engine.

Walter: What are the differences in the different engines, and what should I look out for in my project? What have you done that I could reasonably do to increase the reliable power?

Stephen: What do you still have for parts that you might be willing to part with? Could you provide details, pictures, etc. of the kadett?

Bob: What has been your experiences with the 1.1, and what do you think would be a good middle ground between the stock (no power!) and the awesome engines you have built (give an SR-71 blackbird a run for its money!) for a street engine?

Thank you, I am sure I will find it rewarding. I myself am a bit of an oddball (I think the Messerschmidt Tigers look really cool!)

Darrin
 

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PrOpeller
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I didn't try to increase the hp on this engine since I'm trying to restore the car to stock condition. With the gearing, I'm happy with it regardless... plus it gets GREAT gas mileage and is still quicker than my '72 1.9L autoslug.

The 1.1L S has 8.2:1 compression while the SR has 9.2:1. 75mm pistons, cams, bearings, and sometimes valves are different. Crank, timing chain kit, oil pump, gasket sets, and accessories are the same from what I've experienced. Water pump pulley may be single or double. SR engine in a GT or Rallye has twin downdraft Solexes. When getting parts from Germany, measure your parts first and have them try to match up... a US-spec engine may have small differences in tolerances.

Send Gary your VIN# and radiator brace stamp # to put in his registry of early GTs. Pls post some pics, too.
 

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Discussion Starter · #8 ·
Lets establish a baseline

First off If I want to look at pulling any power out of the 1.1 Litre, then I need to know two things.

What off the shelf performance parts were available, and what was their effect?

Also, is there anyone out there that has modified or raced a 1.1?

Come on, even if it was rumored that your Aunt's Sister's Cousin once changed the air filter on one of these little engines chime in here. Don't let those big HEAVY 1.9 Litres corner the market on performance. :D

Darrin
 

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Re: Lets establish a baseline

rallye73 said:
Also, is there anyone out there that has modified or raced a 1.1?
The only person that I know of currently racing a 1.1 litre GT is Anatoly Aruntinof....he races a 1.1 Opel GT in SCCA's H-Production class. The car is literally painted like a cow...white with random black spots.

About 20 years ago, back when I was working for C & R Small Cars, I recall one guy in Texas had a circle-track 1.1 Opel GT. He sent photos of the car and engine...he had it dynoed and it was making about 115 hp. BUT, all the parts on the engine were custom made one-offs. Custom pistons, custom valves, custom intake, 45 DCOE Weber carb, custom header, etc. Don't remember his name though. But what struck me is the fact that his was the ONLY 1.1 Opel I ever saw heavily modified in all my years dealing with Opels, even though I was in the Opel parts selling business. They're pretty rare.

Bob
 

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Discussion Starter · #10 ·
How would someone get ahold of Anatoly Aruntinof? Is he on one of the lists or does he have an E-mail address?

Darrin
Haven't figured out if Opels are an Addiction or an Obsession.
 

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wel li know ross racing piston has a all opel four cylinder forged piston listing so i thikn that a 1.1 would fall under these terms
but other than that i would say typical head,intake,exhaust,and cam work will do alot
a cam regraind is easy i sure head work wouldnt be hard and exhaust would be on you own and you could prob get an intake made for a 32/36 dk these r my suggestions
 

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Anatoly Aruntinof

I think he lives in the Tulsa, Oklahoma area. He used to own Hallett (race track) just west of Tulsa. He's probably still a member of SCCA. The North East Oklahoma region of SCCA has a Yahoo Group called NEOKLA-SoloII. If your searches don't produce what you want, you might post a note there.

http://groups.yahoo.com/group/NEOKLA-SoloII/


GL

Paul
 

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yeah!

The one I had looked just like that, only straight through for downdraft webers. Man was it fun!
 

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Well, I took a gamble that the early Vauhall Viva/Torano HB OHV engines were basically derived from the Opel 1.1L. Unfortunately, they are not exactly the same... but apparently they do share common ancestry. Here's a pic of the Steinmetz Opel DCOE manifold next to a sidedraft Viva manifold.
 

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PrOpeller
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As you can see, the mounting flange is just a little bit off. I think it'd be possible to make the Vauxhall manifold work with a small amount of machining/grinding. There are not many 1.1L Steinmetz manifolds floating around out there anymore. So this might be an alternative for those looking to add a single sidedraft to their 1100.
 

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propel: they do look pretty much like twins, one just seems taller.
:confused:
rallye73: I'll take a pick of my 71GT. It'll make yours seem like a dream and brighten your day!
:p
 

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PrOpeller
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propel: they do look pretty much like twins, one just seems taller.
Yes, definitely taller...but that should be better for torque anyway. The problem is that the outside mounting bolts and ports are off by 1/8" in each direction.

But if anyone else wants to try and make it work, I think I'll be putting this Viva manifold on eBay soon. Just think of the performance possibilities with a correctly jetted sidedraft. Plus, it sure would be different! (as if the 1.1 isn't different enough.)
 
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