All fair enough- it does use a MAF, it is old and it doesn’t have integrated boost and ignition control- but it is tuneable, more than people think.
For now though the OP has a 15g turbo fitted which means his need for boost or ignition control is going to be fairly limited. Put a revised ignition map in it, fit a manual boost controller set at 15psi and then sort the fuel map out… car should be plenty of fun like that.
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 have considered what you have mentioned with the power steering. and I do agree. a lot of this project will be down tot sting too. I'm sure there will be many more revisions to my initial Hypothesis.
And again I agree about the clutch. I'm sure the lightness will potentially save the clutch...but its also the torque that'll shred it. and these 8v roadblocks do Give a good amount of it.
a TTV lightweight flywheel with an uprated clutch is the future ... but not right now.
ill keep the DMS and standard clutch for now.
as for fully mapping with a stand alone. its a very good idea.....and when its someone else's project and not your money its always easy to suggest these things. like iv said about the clutch and flywheel and power steering I would love all the good stuff but I can't afford it all. so it'll be a later thing if I need it. many people get great results from the LH2.4 with Volvos so for now ill stick with that and all the great experience people have with it.
thanks for all the advice ideas and input. its always good to hear other options and ideas helps lots.
Based on your photos so far I don’t think fitting power steering is going to be an issue- the volvo 240 has the power steering pump on the passenger/left side of the engine and as all redblock blocks have the same mounting bosses, they just bolt on- I have my powersteering pump there, on my 940 engine in my 240.
You’ll just need the 240 bracket, pump, reservoir (some pumps have an integral reservoir) and then lines that connect to the volvo pump one end and the lotus rack the other- might be too much to hope that the standard volvo lines will fit, but you might be lucky…
The reason I'm going with electronic power steering is the rack and track rod ends + mounting points have geometry designed into them. There are no power racks for right hand drive Saab 99s (can get them for LHD). So my best bet is the electronic steering column from something like a Corsa.
IF the Lotus chassis ever had power steering (maybe in a later or higher spec model) you can get the power steering rack from that car and connect the hoses to the Volvo power steering pump.
When talking about the LH fuel injection that's not actually the bit you'll have any problems with. Probably don't even have to remap it. Fuel can be a lot less well controlled and you'll get away with it absolutely fine. The big advantages come from having boost and ignition maps. Then ideally if it can all be combined into one system that's when you're doing well.
The old LH system will flow as much fuel as the injectors and fuel pump can deliver. If you get the fuel injector part number you can find out how much fuel they will deliver and calculate an aprox HP limit.
There's often no requirement to remap LH as it uses a 3d map to calculate the fuel delivery anyway. You have air mass input from the air mass meter and then engine load from the throttle position. If you have a turbo ECU it'll probably have an acceleration enrichment input as well. So if you turn up the boost it'll calculate the fuel requirement using different load points on the map. The factory map is going to have a path through the middle which is what they expect it to use during normal running but there are load points programmed all around the edges of that expected normal usage which will still work for calculating different values. If you're going really crazy sometimes the Bosch injectors have grilles over the tips of the injectors which restrict the flow, you can pull those off and get another 20% fuel from the same injectors.
Ok, I asked on a volvo forum for a photo of a redblock with both the alternator and the power steering pump on one side, which can be done using the bracket on the right in the photo below which originally holds the alternator and ac pump on a Volvo 940 equipped with ac.
As pointed out on that forum though, it’s easier to use an electric pas pump from either a Vauxhall Astra or a Volvo S40 or V40 if you’re short on space. Given that you’ll probably have to get custom hydraulic lines anyway, this seems like good advice- I had a quick look at eBay and they’re available for around £50, which is probably cheaper than buying a belt-driven Volvo pump and messing around with the double bracket etc. that said, if you want to give the double bracket a go the attached photo is of my engine before I stripped it down to put in my 240, so I have that bracket sitting in the pile of ‘might be useful one day’ parts and you can have it for free.