Sooooo many a thing has changed and this project has been delayed and changed, i now own a house
and have my own little garage to work in.
I have still been collecting bits the focus has now changed to fix my 740 rather than work on the 940 project car.
So the new outline is to replace the old leaky, hard to start engine in my 740 that is my daily driver. The main priority is to have a good solid engine that will support good power in the future but to give me a nippy more efficient engine setup for today (ish)
As most of you know to get low end power and off of the line you need to up the fuel... that makes it smokie because the turbo is not lit yet. To make more top end power and the burn the fuel you will need a bigger turbo. So most people would look at going to a compound turbo setup but this add higher drive pressure and is more complex to control and spec.
My solution is an Eaton M45 mixed with an oversized twin scroll turbo and an electronic bypass valve.
I only started working on this is january and i don't really have any major fabrication skill so i'm learning as i go so be gentle
.
The idea is a supercharger blows into the turbo inlet giving the turbo pre-compressed air. As the turbo spools up and the pressure drops between the Supercharger outlet\Turbo inlet a bypass valve will open allowing the turbo to ingest air from the supercharger and a second air feed. This will be controlled by an arduino microcontroller a stepper motor controller, two map sensors and a push to make switch (with additional switches on dash for manual control). I will add a oled screen into the blanks on the odometer to give me live information on pressure and bypass info, air temp or any other info i desire (mess about video on google drive ignore the silliness it was a video i sent to my mates).
The idea is you start the car the egr switch is connected and the bypass valve opens, you put your foot down and pull away the bypass valve closes until you the pressure ratio drops or a timeout threshold is met (ie the turbo is lit or your cruising) this logic is then reset on throttle reset. The bypass will be variable based on if it was triggered by pressure drop or cruise (i would expect on cruise 100% open and a lower percentage on gear change for response). This would have to be tweaked over time to account for driving in traffic maybe a toggle switch for "traffic mode" ie i can just activate the bypass to limit engine load and maybe a "reset" button for overtaking so i wouldn't have to cut throttle to overtake.
Supercharger would have a 2.63 pulley ratio on a 10% undriven pulley and would make 9psi with a max 15.7k rpm (with the engine at 6000 rpm) the T4 crank pulley is bigger than expected
All of this requires a serpentine belt conversion, power steering pump removal and clutched alternator.
Parts involved/available/using so far
4mm Cam Plate (from a Perkins) Bosch 1466111626 (pin needs pressing out and grinding down)
Custom Phenolic intake spacers
Eaton M45 supercharger (mini)
Ebay special turbo (twin scroll)
Ford CMax electronic throttle body (as bypass valve)
Water to air Cooler
N/A inlet manifold
non egr exhaust manifold (for Twin scroll conversion)
VW T4 crank pulley 18/19cm
VW T4 alternator
T3 Flange (for twin scroll insert)
Longer exhaust stud (M10 x 52 (Ford))
Recon Steering rack (not this it matters for the build)
Ordered and waitting on delivery)
MONARK DN0SD293 injectors (Germany)
6x D24 ACM Connecting Rod (Sweden)
VAUXHALL ASTRA G MK4 POWER STEERING PUMP
(not using the 12mm pump as thats for the other project/money pot)
Things i still need to get/do
Head rebuild
Rebuild engine
Ve Timing spacer
Clutch disk (have a sach pressure plate available)
Flywheel checked
Money shot - I have welded more since just a rough look
Google Drive link with all pictures as i go along i will upload them if anyone is interested
https://drive.google.com/drive/folde...GA?usp=sharing