Does the "Volvo contactless rotary sensor system" in your item description solve the issue quoted above?I know you have all lost interest in my lock down project, but i have made some interesting observations in my testing. I am wondering how many people have a contactless upgrade and have unsteady idle or problems driving and control, especially at low revs?
It seems we have been upgrading these ETMs with hall effect contactless throttle position sensors and yes this stop them wearing out, but they are very prone to interference from magnetic sources , like err well the throttle body motor!!! I have converted 4 of these with contactless rotary sensors and 2 of these were fine and 2 had instability problems after the upgrade, subtle but there nevertheless.
I have had a contactless upgrade on my throttle body for many years and its been very reliable but I have had occasional unsteady idle and odd revving of the engine, and I now see its been the hall effect rotary sensor all along. I have now had various other throttle bodies (8 or 9 in total) on my car and its clearly not the car, it really is the throttle body. With the right ETM the car starts like a rock and idles rock steady.
I have not worked out the perfect solution to this but i am working on it. It may actually be better to put a new high reliability contact, carbon track rotary sensor on the ETM which is not affected by the motor.
Was thinking more utilising the Bosch unit for the 32 , after all it has been done on the Lambo. Are we saying the new contactless Magneti (Volvo) units are sorted now though?well yes I was a aware of this, not sure I am that keen to get into another one, and problem would be a car to test any modifications on? Perhaps an excuse to buy one!!!
I am beginning to think just that sir. I have had my car for 14 years and its always had a tendency to idle slightly unsteady, and like you i have had a couple of TVR V8's that ticked over like a metronome and I just put it down to the highly strung engine in the Maserati, but it looks like its probably this stupid throttle body. I have one in my car now and it ticks over absolutely steady. I have another couple on my bench where it drifts gently up and down!! its not the engine!!
Well when I first got this conversion to work it worked without errors but did not feel right and there was a definite hesitation from idle and low throttle. I initially tried just tinkering with it, but realised that both this is very subjective and also not very repeatable. So thinking about it, its a choke which restricts air flow, so I made a computerised test rig which measures the air flow choking effect and mapped several original Maserati units and then started to try and match the air flow profile of the converted units to the Maserati onesI don't think a little hunting on idle is a problem, about 50 RPM, mines always done this
What's more of interest is how's the drivability of this new Volvo version comperes to original factory unit if there is any
Over to you Davy!
Dave
Also i think the hunting is possibly a product of the engine, ands its almost impossible to remove this completely, but it can be kept to a minimum.I don't think a little hunting on idle is a problem, about 50 RPM, mines always done this
What's more of interest is how's the drivability of this new Volvo version comperes to original factory unit if there is any
Over to you Davy!
Dave
Well yes I reckon you are right there. However its worth noting that some of these throttle bodies when not on the car sitting with a fixed demand on them the flap moves gently, suggesting a problem with the feedback system in the electronics. Its a lot worse with the contactless rotary sensors than with the original carbon track units, which also suggests these sensors are affected by interference from the main motor magnetic field. But with careful set up and a bit of messing around it can mostly be cured, I have a few here I think will just go in the bin as I cant get them to run stable at all.Well done.
I reckon the hunting at idle is a function of the large x section of the throttle body and the fact it needs a very small change in air volume to raise the revs.
If you look at the like of the efi on Rover V8 they use an air bypass channel and needle to set idle and a lot of more modern stuff has a separate idle control valve with much smaller x section than the main throttle body. Doesn’t happen with a carb as there’s no feedback loop.
Wondered about this too. Then remembered that the last thing my own 3200 needed was more power . Better headlights, more rear grip and maybe reduced thirst. One rolling road day measured my car 390bhp. Many others went on the same kit, several modern Ferraris at 90% of quoted stock values, Gallardo measured under. Only other things that measured up was freshly restored Daytona and devilishly loud 911 (964 with modified exhausts).I wonder if a little bit of old school cylinder head work on a 3200 now you can flow more air with Davy's TB, maybe a genuine 400+ hp is possible
I've recently tried this with my 1980's Uno Turbo, once you get over170hp at 1.2 bar boost pressure the magnetti marelli digiplex old school ecu can't cope with the fueling even with larger injectors
It runs lean at the top end, runs out at about 130mph.... then its melted pistons!
Dave
Hi how much are you Volvo conversions - 2001 3200 GTA Assetto Corsa. Thanks, NigelI am pretty pleased with the results I am getting with the Volvo units and especially taking the brand new Swedish built Volvo units and converting these for the 3200, its a little expensive but results are great and I reckon it's as sorted as it gets, I have one in my car and prefer it to my old OEM unit, bullet proof reliable.
Results stripping and upgrading older Volvo units is less easy, but equally this has also worked and a small cluster of happy owners it seems so far, and a collection of ETM's in my workshop waiting for inspiration.
The Bosch unit would require a lot of work I suspect just getting the code to work, and yes its possible but since I can get new Volvo units and make them work I am kind of content to just run with that for the moment. The Bosch units would almost certainly be cheaper right enough, and that's attractive. I need to get less busy so I have time to tinker with it!!!