Like this project. It's got just the right amount of crazy / bodge / attention to detail for me.
On the steering front, I think it would be a big mistake to leave power steering off. I understand if you want to skip the PS so you can get it on the road quicker. It's something you can leave out initially and the car will be on the road sooner. The benefit of power steering isn't really the easier parking when it comes to projects like this. I don't have power steering on my old Saab and there's a real big issue in not having it. When you're traveling at speed and want to change direction quickly the weight of the car will try to push on and fight you. With power steering you can easily point the car in the right direction, without it... not so much. You're far more at the mercy of physics and that's why I'm going to fit an electronic column to my Saab. You can get them from Vauxhall Corsa as a self contained unit.
I also think it might be worth trying out the existing / standard clutches. Although there is going to be more power coming out of the motor with the car being a lot lighter you'll probably find a standard clutch is okay. Remember Volvos are 5-seat estates with caravan towing ability factored in. I'd be surprised if the extra power turned out to be too much for a clutch that would normally run a Volvo reliably.
Definitely lighten the flywheel though. The flywheel weight should be proportional to the weight of the vehicle. So a standard Volvo flywheel is going to be way too heavy for a Lotus with extra added lightness. If a flywheel is too light the car becomes difficult to drive... but you've removed a lot of weight so you could have a really light flywheel in your setup.
I'd get it on full mappable engine management with boost control and importantly CDI ignition as soon as possible. Don't bother trying to tune the LH stuff, we have it on Saabs and it's carp. I used to be able to burn chips for the LH computers but it's just not worth it. I've still got the chip burner but it is a total waste of time.
I’m going to be doing a lot of the same work to my Elite so I’m taking notes on the brakes and such. Planning an ecotec attached to a NC 6spd so it should go pretty well. What are your shocks from, I may have missed that
I really wouldn’t attempt to lighten the Volvo flywheel- they’re cast and there are enough stories of them exploding after lightening attempts.
As your engine is fairly late it’s likely to have a dual mass flywheel fitted, if so it’s worth swapping it for a significantly lighter single mass flywheel which came on the earlier 940s and late 240s. Also called a dogdish flywheel, they come up on eBay and on volvo fb pages pretty often. A turbo diesel clutch for a 940 is enough for most even fairly tuned setups, I have a dogdish flywheel with a TD clutch fitted to my car with a 19t and 260bhp and it’s absolutely fine. All of the above would be a direct swap onto your engine and gearbox.
If you want a lighter flywheel then ttv make a steel one which fits with a volvo 850r clutch, which is expensive but a really nice solution- and won’t explode and cut your feet off
How heavy is the car, do you know? Both a Volvo 240 and 940 are around 1400kg.
I only half agree with the comment about about Bosch 2.4lh- yeah it’s 90s tech, but it is fully tuneable (thanks to a lot of highly motivated swedes hacking the system completely). If you buy an ostrich chip emulator that plugs into the chip socket and download tuner pro rt (for free) you can make changes to the fuel map in real time. I have a wasted spark setup on my car which is an easy upgrade/swap and removes the need for a distributor.
Ok so you might not get quite as much out of the engine as if you swap to a modern standalone, but you’ll have spent far less… and you can always swap to a standalone later.
Anyway, following with interest- looks like a really fun project
I thought LH used an air mass meter? That's reason enough to get rid of it. Then the issues of it not being integrated with boost and ignition control so the left hand doesn't know what the right hand is up to.
+ with the ECUs becoming old all the chips will be past their working life so on a trajectory to failure sooner or later. They may never fail but it is a fact that chips have a lifespan recommended by the manufacturer which is around 10-15 years so could just stop working. I've seen plenty of LH units where they expired early!