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Mk1 Build Thread

MK1 Build Thread

I got this clip to hold my clutch cable... no more cable tie





























So the rubber stopper on my GW clutch cable tore in half...GW piece of sh*t, so I decided to modernise... I chose the modern clutch cable and associated parts. I would recommend this mod for every old Citi. The clutch pedal is now much more smooth and requires less force to operate which is awesome for traffic. I forgot to take a picture of the clutch cable mechanism that is attached on the cabin-side of the firewall before the clutch pedal. Please excuse the quality of the pictures, they were taken with my cell phoneI got this clip






























Needed space to drill holes in the firewall and access the clutch mechanism






































































































































































2 holes were drilled into the firewall to mount the clutch mechanism

































I also got the modern clutch cable "holder" that is bolted to the gearbox
No mods to the pedal linkage. I've taken some pics to show you.






























Holes drilled from engine bay side of fire wall. The ADY intake mani is smaller than mp9 one, so only throttle body needed to be removed.






























Here you can see the inner clutch mechanism attaching to the clutch pedal






























I thought my master cylinder wasn't looking too great, so I gave it, surrounding brake lines and coolant bottle cap a spray of blue engine enamel





















I have been wondering since I got my ADY motor why the intake plenum chamber is smaller and why the runners (cylinder 1 & 4) are shorter than the digifant, K-jet and MP9's plenum chambers . I read in this months SnS mag (88Rsi's Conquest in the under construction section) that an intake plenum chamber which is as small as possible is great for throttle response. I spoke to Steve Hurley from Koni SA (he has been involved in various forms in VW racing cars for many years) and he said that the intake manifold (small plenum chamber and runners) make a motor produce more kw but less nm than a large intake manifold. I agree with this statement: My ADY 2l 8v motor makes less nm than most modded 2l 8v motors (forum users with 2l 8v motors with similar kw) but slightly more kw @ KAR dyno. This applies to the bigger MP9 and K jet intake manifolds as well.






























Interesting reading:

http://www.superchargerperformance.com/ ... old-design

"The compromise in plenum volume is as follows:

A larger volume leaves more available air to the engine within its reach, and so long as this air can be replenished in time through the intake system, then the engine never has to work hard to get intake air because there’s always enough of it sitting there in the larger plenum.

As the plenum volume gets smaller, it becomes easier for the engine to rapidly consume all of the air in the plenum and thus it would have to spend a lot of effort (after the initial draw of air) trying to suck air in all the way through the entire intake system to stay alive.

The problem with a larger plenum is that it hurts throttle response. Throttle response is very much affected by throttle pressure (or in other words how fast the engine can consume all the air in the plenum and create a significant amount of vacuum in the manifold to draw in fresh air). The smaller the plenum (or smaller the runners), the higher the gas velocity, the faster the pressure drop, the sooner the new air rushes in, the faster the throttle response.

This usually leads to an oddball design by most OEM’s of an oversized plenum wit h a smaller throttle body and runners to try to boost gas velocity, or an undersized plenum (that will be consumed faster for better response) but with a larger throttle body that will not bottle neck the engine as it tries to pull in more air from the outside to stay alive at higher flow demands at higher rpms.

Either way, shifting peak power from 5500 to 6200 has a potential increase of 12% especially coupled with a properly designed exhaust manifold, appropriate camshafts, and a proper tune..."

http://www.superchargerperformance.com/ ... e-response

"From a technical point of view, throttle response can be measured by has your engine can build vacuum in its intake manifold i.e. via throttle pressure. The faster and higher peak vacuum is reached in the intake manifold, the higher the pressure differential will be between outside air, and your engine. This pressure differencial forces the air to flow from the area of high pressure (outside air) to the area of low pressure (the engine and cylinders), and the higher the pressure difference, the greater the pressure force, and the faster the air flow into the engine.

This is essencially how throttle response works. To improve throttle response several engine alterations can be used to achieve a higher peak vacuum in the engine or a faster change in vacuum per throttle input… some of these include:

1- Using undersized intake pipes and intake plenum runners to increase the airflow velocity in the intake system, making the engine able to suck all the air out of it faster and create vacuum sooner.

2- Adjusting intake cam timing to open the intake valve as peak vacuum is created inside the cylinder near bottom dead center.

3- Reducing the overall intake system volume, by using smaller manifolds, less vacuum lines, and more electrically operated (rather than vacuum operated) engine auxilliaries which means the engine has less air volume to clear from the intake system to create a vacuum in the manifold to force new air in.

4- Using cam seperation and cam overlap (when both intake and exhaust valves are open at the same time) to have the previous cycle’s exhaust gasses help pull in fresh intake gasses for the beginning of this combustion cycle."
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