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
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.
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.
Primary: 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 sequential ignition
- 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
Update on this:
- I'm through the first stage of basic sensors and running in sequential mode, but the injectors are not aligned with the valves.
- Coils fitted and working.
- Some extras added - single WBO2 fitted, waiting for the second one.
- Large injectors fitted for future plans. Much better than the standard ones.
- Some tuning of ECU done. Car goes quite well!
- Performance exhaust manifolds fitted
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.
- Working on a new twin throttlebody plenum. Not happy with the 8 TB solutions I've seen yet, so this will do until I have time to plan more.
Target date for having fully complient system for UK emissions tests is November 2006. This is now "unachieved" as I have no cats in the car for the moment.
Have coils & big injectors fitted by May Achieved
Running by June Achieved
Fully mapped by July. Ongoing - delay from exhaust problems
pushed this to end of July/beginning of August. Mapping is "good enough" for the moment
Rolling Road session booked for beginning of August.
Now rolling roaded - the car produced 260 bhp @5500 RPM and 320 ftlbs @ 3000 RPM. Not quite what I wanted, but it highlighted some fundimental problems with the design of the intake manifold & induction system. See the non-vems related pages for more details.
New inlet manifold designed and fitted. A little more rolling road time has resulted in a significant improvement.
Shortly after the above run, the clutch died, followed by the diff. This took a couple of months to source parts and repair. Obsolescence is not a nice thing.
The torque plot looks a lot cleaner now there's no slip.
The steep dropoff at the top end is mainly due to using 95 RON fuel. There should be a bit more power from more ignition advance, but there's no point for day-to-day running.
The mixture settings measured by the dyno were pretty good.
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. Also considering running on E85 fuel.
Update: Nothing new here, other than I've found (but not fitted) the sensors I need. The plan is to fit these during the body-off restoration that is happening this winter.
Body-off restoration completed. Car looks like new underneath now.
Milestones along the way...
Fitting & testing the crank & cam triggers: MembersPage/DavidBlades/TrigTest
Fitting and testing other sensors: MembersPage/DavidBlades/SenTest
Injector Setup & Config file: MembersPage/DavidBlades/InjSetup
VE, Lambda tables & tuning the fuel: MembersPage/DavidBlades/FuelTest
Starting and Warm-up: MembersPage/DavidBlades/StartingWarmup
Acceleration Enrichment: MembersPage/DavidBlades/AccelEnrich
Idle control: MembersPage/DavidBlades/IdleControl
Cooling fan control & other ancilliaries: MembersPage/DavidBlades/FanTest
Fitting Ignition system: MembersPage/DavidBlades/IgnSetup
Non VEMS related issues: MembersPage/DavidBlades/NonVems
Problem page: MembersPage/DavidBlades/RegulatorProblem
Testing the car & ECU: MembersPage/DavidBlades/TestingEcu
Firmware feature requests
Ideas for firmware improvements: MembersPage/DavidBlades/DualWb
Page about getting TCS inputs:
Other Projects that are now in progress
(Or if it moves, it could do with VEMS)
- "Plug and play" harness solution for Subaru Impreza MembersPage/DavidBlades/Subaru
- Pugzilla - a mutant Peugeot 309 track & autotest car.
- Nissan 200SX (S14a) - another track day car, but must remain road legal.
- BBE Quark kit car. (You'll never have heard of it - I've not built the prototype yet!)