Technical Easiest parts to gain 2-3hp?

[darkstrike]

Hi all!

Thinking about options for my 126 when I go about importing one here to Canada. I'll probably be going for one of the later model 126ps (ELX) as a good friend has 1999 ELX in Poland.

That being said, things are pretty wide open and far apart here in Canada compared to what a lot of you are used to in the UK/Europe. I want to keep my 126 mostly stock, but I also want it to be the first car I start working on mechanically in earnest - something to tinker with!

If I were to keep my 126 mostly stock but just wish to add a few more horsepower, what's the easiest way to go? Exhaust for one, I'd think? The speed limit on most roads here is 80kph where I live, so a few extra hp to keep me at speed going up hills with the huge Chevy, RAM and Ford trucks behind me!

 

[gadge]

There aren't many bolt on mods that can extract power from the 650cc twin I'm afraid. An exhaust and a different carb many unleash 2hp maybe 3. Most of the big HP gains (by big I meant over 30 ) are made with lighter flywheels, bigger barrels and a different head. If you spend the money 50hp is possible which doesn't sound much but that's double what it left the factory with and plus it only weighs around 650kgs so it's power to weight is pretty good

 

[darkstrike]

Hi Gadge!

Thanks for the info! I wasn't looking for any huge gains, just a few extra hp without compromising reliability - even a gain of one or two would probably be noticeable with the small amount of hp already on tap and the car's already light weight (keeping in mine I have never driven a 126 in my life, let alone even seen one in person!). I had just been thinking things like an exhaust swap or cooling fan swap...?

Speaking of the cooling fan..I know the engine has to spin that, so there is parasitic loss there. Are those aftermarket aluminium fans decent replacements? Lighter, so they are sucking up less horsepower through parasitic loss then, but are they as effective at cooling?

Not sure I would want to change the carb...if I stick with the original one, I'd imagine I'd have more information available for tuning it when the time comes.

As for flywheel swaps, more hp, but higher revs to accomplish anything, right? Harder on the engine?

 

[gadge]

Any moving component that's replaced with a lighter item will help horsepower from being absorbed away so a lighter fan and flywheel could "unleash" 1-2 HP even fitting and electric fuel pump my help as its one less item that the engine has to operate, however the lighter you go the more you rely on revs to keep everything going so you loose out on torque (the 126 has a very good low torque range) and it will idle rough aswell as it struggles to tick over.

 

[darkstrike]

Hi Gadge,

Maybe a different carb would be a good choice down the road. Would just an exhaust upgrade on it's own be a worthwhile investment or would I notice absolutely no difference...?

 

[gadge]

a really well chosen exhaust could help gasses escape more efficiently and certainly is well worth doing just for the sound however I've always thought that Sports exhausts tend to work best with other tuning parts so for example a free flowing exhaust would compliment a sports camshaft or a bigger carb. if you can get the air/fuel in and the spent gases out more efficiently then you will gain power. The other way is to lighten components so that the Pistons have less work to do but this involves money.

If it's bolt on mods your after then i'd say a bigger carb and a sports exhaust is then way to go but with all tuning your gonna have to spend the dollars

 

[gt alex]

Hi the first mod I did to mine was a 1 1/4" fish carb about 32mm it is straight through more like a throttle body. It made a big difference especially going up hills. No longer 2nd gear on 70kph roads, just put your foot down and at worst 3rd gear but much nicer to drive and using less fuel.

 

[darkstrike]

Hmmm...sounds like an interesting choice! I assume you couldn't use the stock air cleaner setup for it though? Also assuming metalwork was involved?

 

[Rcl]

A very mild cam with extra lift might also give you the extra torque.
I once found one (for my 500 at the time) in a parts-engine, tried it, and found it very profitable in terms of driveability.

 

[gt alex]

Yes I am using the stock air box but with a sports filter inside. I fabricated a plenum for on the carb but I first drove it with a racing air sock on the carb which made it louder than the standard exhaust. the air box made it quieter but back to back testing show a power drop but thats how I drive it, still heaps better than standard.
As for cam I think the 126 cam is already a bit better than the 500.
I will be testing exhaust systems over the next couple of month hopefully with dyno test results.

 

[darkstrike]

A very mild cam with extra lift might also give you the extra torque.
I once found one (for my 500 at the time) in a parts-engine, tried it, and found it very profitable in terms of driveability.

Hmmm...sounds like a cam would be a nice compromise. I want to try and keep my car as stock as I can when I get it other than maybe a tiny performance bump and some new wheels. The cam would help without looking noticeably unoriginal! I have a Service Manual for the car, but I imagine the cam would be a lot of work to replace...?

Yes I am using the stock air box but with a sports filter inside. I fabricated a plenum for on the carb but I first drove it with a racing air sock on the carb which made it louder than the standard exhaust. the air box made it quieter but back to back testing show a power drop but thats how I drive it, still heaps better than standard.
As for cam I think the 126 cam is already a bit better than the 500.
I will be testing exhaust systems over the next couple of month hopefully with dyno test results.

Ah, sadly any fabrication work around here is very costly and I don't have the tools or knowhow to do it myself....will be interesting to see your results though!

 

[gt alex]

You have got me thinking and that could be dangerous, instead of a cam change, are there higher ratio rockers that could fit the 652 engine? to open the valves a bit faster with more lift.
In my past I got good results with a vw engine and high ratio rockers. easier to fit than a cam and standard looks.

Also some pictures of mine.
No roof doors or glass is sure to make the Lorenz model a bit quicker than the average 126. Also a pic of the fish carb and standard Exhaust with the outlet shortened. and a muffler I have started to modify that I will try if the Michael Speeder exhaust fails to perform.