Opel GT Forum banner

21 - 40 of 50 Posts

·
Registered
Joined
·
651 Posts
So I watch this video and think 'That is really too quiet'....Then I turned the speakers ON. Impressive, I WANT ONE !
 

·
Registered
Joined
·
69 Posts
Discussion Starter #22
Dyno runs!! So after a bit of tuning the new engine is living its best life from what I can tell. Here's the dyno chart with the previous setup on there for comparison. The new pistons/rod combo really woke this engine up. The cam is a mystery re-grind that come with some parts I bought and it has about .75mm more lift than stock. No idea on the what rest of its profile is though. Compression ratio is about 9.7:1 after some pretty aggressive head milling. Runs well on California pump gas.

76.5 HP at the wheels is pretty satisfying for a 1.1 OHV to say the least. It's not a fast car by today's standards but has a really fun personality and feels just right for what it is. I'm going to leave the engine alone for now and move to other madcapped schemes to make the car better. Stand by...
 

Attachments

·
Registered
Joined
·
2,015 Posts
Very impressive accomplishment!
Your making as much wheel hp as many 2Ls are! Thanks for posting this update
 

·
Registered
Joined
·
69 Posts
Discussion Starter #24
None of this was very expensive is the good news. The BMW/Mini pistons and rods are readily available on ebay and the machine work to fit them is just typical stuff. Putting the Honda valves in the head was a bit more of a science project but again, a regular automotive machine shop was able to do the work once I explained the goal.

Let's hear it for the 1.1! I'm betting that an OHV Kadett could be a pretty decent force in vintage racing up against Sprites and such.
 

·
Registered
Joined
·
2,015 Posts
Agreed! It's so impressive what you accomplished with nothing more then 1100cc! Seriously man that's cool, and you have dyno data to back it up with!!! Awesome project
 

·
Registered
Joined
·
2,015 Posts
Bump!

Simply a cool completely odd ball engine build!
 

·
Registered
Joined
·
8 Posts
None of this was very expensive is the good news. The BMW/Mini pistons and rods are readily available on ebay and the machine work to fit them is just typical stuff. Putting the Honda valves in the head was a bit more of a science project but again, a regular automotive machine shop was able to do the work once I explained the goal.

Let's hear it for the 1.1! I'm betting that an OHV Kadett could be a pretty decent force in vintage racing up against Sprites and such.
I appreciate very much your work on this engine ... I also like to thank you for sharing your experiences ... I will start overhauling a 1100SR engine these days ... The looks of it will be like when it left the factory, But ... I will definetely go for the Minicooper pistons + conrods ... Are those from the basic 1.6 - engines from 2001 - 2007 those that I want ? I will also do some upgrade on the cylinderhead ... , of course ...
 

·
Registered
Joined
·
69 Posts
Discussion Starter #29
Hi-

Yes, you want to base model Mini pistons like this one:


You'll have to bore the block to 77mm and cut the crank journals for the Mini sized bearings. It's not a big change to the crank but make sure your machine shop makes a generous radius at the ends of the journals for maximum strength. The Mini rods are a tiny bit narrower than the Opel ones so they float a bit on the crank journal. I was concerned about this when I built the engine but now that I've run it for months including a full 24 Hours Of Lemons race with this setup I can say it doesn't matter. The pistons sit a tiny bit above the block deck and with a stock 1mm head gasket you end up with a zero squish engine. Perfect fit. Do not deck the block.

As for the head, take a look at Honda K series valves. They are even bigger than the ones I used and can be modified to fit by a good machine shop. Depending on how much you cut down the head for compression you might have to notch the pistons a bit for valve clearance. With the Honda B valves I did not have to notch with a stock cam even after cutting 1.5mm off the head but the K valves are bigger.

Keep us posted on how you do. Just doing the Mini pistons alone will get you solid gains because of their lighter weight and lower friction design. If you can stand to look at a programmable ignition I would use one because once I figured ot out on my car it really helped.
 

·
Registered
Joined
·
757 Posts
Since Professor Dremel seems to live in Norway, why not base the build on a 12S or N instead ? More power and torque than from a 1,1 liter. Have you read these ?
 

·
Registered
Joined
·
2,015 Posts
Since Professor Dremel seems to live in Norway, why not base the build on a 12S or N instead ? More power and torque than from a 1,1 liter. Have you read these ?
What a great read, Thank you for posting it! Very interesting indeed.
 

·
Registered
Joined
·
69 Posts
Discussion Starter #32
PDM Clark's work is amazing. I bet there are options for new pistons and rods that would work in the 1.2 block if you looked. Don't forget to check motorcycle applications as well because some of those are around 81 or 82mm. Here are some possible options:


Volvo 81mm bore pistons. Any modern car piston will be a huge leap forward in weight and durability.


The Suzuki Hayabusa is also an 81mm bore. Parts for sportbikes are really cheap because their life is often short.

I found all this after a few minutes of searching. Look deeper and keep us posted!!
 

·
Registered
Joined
·
8 Posts
Hi-

Yes, you want to base model Mini pistons like this one:


You'll have to bore the block to 77mm and cut the crank journals for the Mini sized bearings. It's not a big change to the crank but make sure your machine shop makes a generous radius at the ends of the journals for maximum strength. The Mini rods are a tiny bit narrower than the Opel ones so they float a bit on the crank journal. I was concerned about this when I built the engine but now that I've run it for months including a full 24 Hours Of Lemons race with this setup I can say it doesn't matter. The pistons sit a tiny bit above the block deck and with a stock 1mm head gasket you end up with a zero squish engine. Perfect fit. Do not deck the block.

As for the head, take a look at Honda K series valves. They are even bigger than the ones I used and can be modified to fit by a good machine shop. Depending on how much you cut down the head for compression you might have to notch the pistons a bit for valve clearance. With the Honda B valves I did not have to notch with a stock cam even after cutting 1.5mm off the head but the K valves are bigger.

Keep us posted on how you do. Just doing the Mini pistons alone will get you solid gains because of their lighter weight and lower friction design. If you can stand to look at a programmable ignition I would use one because once I figured ot out on my car it really helped.
I have bought 4 of those !!!
 

·
Registered
Joined
·
69 Posts
Discussion Starter #35
You should put the Mini pistons and rods in the SR engine! You'll get great results even if you do no other modifications. They are much lighter and will last a lot longer. Keep us posted on what you end up doing!
 

·
Registered
Joined
·
8 Posts
You should put the Mini pistons and rods in the SR engine! You'll get great results even if you do no other modifications. They are much lighter and will last a lot longer. Keep us posted on what you end up doing!
I picked up two engines today; One 1100SR and one 1200 ... I guess I have to build them both ... I will start taking the engines apart tomorrow ...
 

·
Registered
Joined
·
2,015 Posts
I picked up two engines today; One 1100SR and one 1200 ... I guess I have to build them both ... I will start taking the engines apart tomorrow ...
Post many pictures please!
 
  • Like
Reactions: Professor Dremel
21 - 40 of 50 Posts
Top