About time I got started...
I have a TVR Griffith 500. It's a great car, but could be so much better with the right engine management.
My aims are to:
- Increase my knowledge of engines and mapping
- Make the car easier to maintain and modify
- Avoid potential problems with obsolete parts
- Gain more power from the engine while using less fuel :-)
- Aid with the development of VEMS
A few words on the car
[Add pic of Griff here]
It's a light (1078kg) 2 seater convertable with a 5 litre Rover v8 engine (only 2 valves per cyl :-( ) made by a small company in Blackpool. There are no active safety features at all, so you have to drive it properly.
Modifications to date are uprated suspension, uprated brakes, polybushes and a large alloy radiator.
VEMS setup
Since I'm very time limited for the moment, I've gone for a fully assembled genboard 3.3 with all the bells and whistles.
I plan to have:
- the usual sensors (MAP, IAT etc...)
- fully sequential ignition and injection
- 2 WBO2s
- dual knock sensor (even having 1 is an improvement!!)
- 1 acoustic is supported, 2 channels require firmware mod
- Ion Sensing needs new hardware
- OK, forget ION sense for now. 1 acoustic is good enough.
- EGT (eventually)
Trigger setup
Primary: 32-1 (not 36-1) tooth wheel on crank, and Ford VR sensor
Secondary: modified distributor with hall sensor - the advance and reterd mechanism will be locked and the factory sensor for the timing will be modified to produce one pulse per rotation instead of the usual 4. (I may make this neater in future and put something directly on the cam wheel as this will be 0.01% more efficient ;-) )
Order of work
Get VEMS up and running in place of the Lucas 14CUX using the basic sensors. This will be injection only, running batch fire (max 2 injectors per batch instead of 4)
Replace ignition system with 8 coilpacks. )Shame Subaru ones don't fit - I've got loads of them.)
Start to add the "extras" like WBO2
Do some tuning :-D
Tuning
New exhaust manifolds will find their way on the car as the original ones aren't the best design. Also, the intake system could be redesigned to use 8 throttle bodies. Plenty of scope when there's a nice ECU dealing with it all.
Completion Dates
Target date for having fully complient system for UK emissions tests is March 2006. This will require at least one WBO2 sensor (preferably 2)
Other plans
One goal is to reduce the cars fuel consumption. To this end, I will be investigating "displacement on demand" - ie not fuelling certain cylinders depending on the engine loading. This nicely ties in with the actuation routines for traction control - another thing I plan to look at next year.
Firmware support
Page about dual channel wideband lamba: MembersPage/DavidBlades/dualwb
Page about getting TCS inputs:
MembersPage/DavidBlades/TCSInputs
- there are 8 free 12-bit AD inputs. However they must be connected to connectors, only very few are buy default - I check your ECM before clamping. I can do these checks as and when I need them. (Won't be for a while - I need to get the standard stuff working)
- TCS needs analog input (not freq) ?
- I didn't expect there to be 4 spare inputs for new frequency inputs... So the wheelspeed is freq-signal (with ... pulses/rotation * wheel circumference = ... pulses / km, but) you want to use monostable multivibrator and lowpass filter circuit to convert freq to analog signal ?
- I don't want to, but it appears that is what is fitted on the car at the moment. I would prefer to just use something like 4 ABS sensors and tone wheels and be done. That is if I can fit it all into the ECU inputs.
- "Actuators" for TCS - fuel cut, ignition retard, ignition cut etc.
- these actuators are already implemented (these were needed for ALS, see MembersPage/GaborRacz/NewAlsLaunchAndOthers)
- Good enough for me...
Thanks for any answers! Some of the wiki is not clear on these things (or I'm no good at finding stuff). If there's anything to do, I'm happy to do some coding on the project - it's what I do at work after all... :) )