Turbo Charged Rover V8 using stock 14CUX efi
Discussion
Thanks for that! I've not finished my car yet but when i get it running it looks like i trip to see Mark then!
14CUX is the standard EFI fitted to shed loads of V8's, mine is off a 4.0L TVR.
Any idea what it would drive like with a stock fuel map? maybe just fit a FSE regulater for the extra fuel under boost until i can get it mapped properly?
I've decided to fit my flow meter in the boosted side of the turbo just before the throttle so it measures the true air mass as it enters the engine. (the turbo will heat the air so installing the flow meter on the intake of the turbo means that the flow meter will be measuring air at a differant temprature the the engine is receiving, hence different air mass)
Do you think that's correct? or am i been stupid!!
14CUX is the standard EFI fitted to shed loads of V8's, mine is off a 4.0L TVR.
Any idea what it would drive like with a stock fuel map? maybe just fit a FSE regulater for the extra fuel under boost until i can get it mapped properly?
I've decided to fit my flow meter in the boosted side of the turbo just before the throttle so it measures the true air mass as it enters the engine. (the turbo will heat the air so installing the flow meter on the intake of the turbo means that the flow meter will be measuring air at a differant temprature the the engine is receiving, hence different air mass)
Do you think that's correct? or am i been stupid!!
It won't last long with just a boost referenced fuel regulator on it. You could use the stock ecu and a piggy back unit for extra fuelling or better still you could use a stand alone ecu with a MAP input. A lot depends on the compression ration you have chosen to use and your budget/future plans.
Thanks for you comments BoostedLs1,i will prob ask Mark Adams to remap the 14CUX ecu if he is available. The engine is a 3.9L with 9.0/1 comp ratio, v8developments MC1 (turbo version) fast road cam, stage 2 heads with full injection system from a 4.0L TVR, one TO4B turbo and intercooler from an RS500 cosworth.
What do you think about the location of the flow meter?
GreenV8S, i'm using the standard distributer with MSD 6BTM ignition (the MSD box connects to the inlet manifold, it has a 1bar MAP built-in)It also has a ajustment that you install inside the car so you can ajust in real time the amount of retard per pound of boost, min 1 degree per PSI to a maximum of 3 degrees per pound of boost.
what fuel systems/ignition do you run on your cars?
Sorry about all the questions, not done much work with the Rover V8 before, normally play with Fords!
Dale.
What do you think about the location of the flow meter?
GreenV8S, i'm using the standard distributer with MSD 6BTM ignition (the MSD box connects to the inlet manifold, it has a 1bar MAP built-in)It also has a ajustment that you install inside the car so you can ajust in real time the amount of retard per pound of boost, min 1 degree per PSI to a maximum of 3 degrees per pound of boost.
what fuel systems/ignition do you run on your cars?
Sorry about all the questions, not done much work with the Rover V8 before, normally play with Fords!
Dale.
Does the MSD 6BTM use a separate crank trigger, or the existing dizzy electronic points? Is it expensive compared to eg Omex ignition-only systems?
The mass air flow rate is the same either side of the compressor, just the temperature and pressure change.
The hotwire sensor is designed to compensate for pressure and temperature changes and produce a 'true' mass measurement rather than for example air volume flow. However, I don't know if the temperature/pressure correction would remain accurate at the sort of temperatures and pressures you would get downstrean of a turbo. Also I don't know how tolerant hotwire meters are of turbulent air, they measure local air velocity at the sensor and a highly turbulent flow might confuse them. There is an upper limit to the amount of air flow the hotwire meter can measure accurately. I think this corresponds to roughly 300 bhp worth of air flow. Beyond this point as I understand it the meter doesn't stop working but becomes unresponsive to increased air flow. This might mean that past this limit the engine tends to run lean, which is probably the wrong answer. The Bosch hotwire sensor has a higher range, and there is a supercharged version used on Jags which is calibrated up to a higher range still. The Bosch meter isn't a plug-in replacement for the Lucas one, but can be used with a simple wiring change.
>> Edited by GreenV8S on Thursday 14th October 13:05
The mass air flow rate is the same either side of the compressor, just the temperature and pressure change.
The hotwire sensor is designed to compensate for pressure and temperature changes and produce a 'true' mass measurement rather than for example air volume flow. However, I don't know if the temperature/pressure correction would remain accurate at the sort of temperatures and pressures you would get downstrean of a turbo. Also I don't know how tolerant hotwire meters are of turbulent air, they measure local air velocity at the sensor and a highly turbulent flow might confuse them. There is an upper limit to the amount of air flow the hotwire meter can measure accurately. I think this corresponds to roughly 300 bhp worth of air flow. Beyond this point as I understand it the meter doesn't stop working but becomes unresponsive to increased air flow. This might mean that past this limit the engine tends to run lean, which is probably the wrong answer. The Bosch hotwire sensor has a higher range, and there is a supercharged version used on Jags which is calibrated up to a higher range still. The Bosch meter isn't a plug-in replacement for the Lucas one, but can be used with a simple wiring change.
>> Edited by GreenV8S on Thursday 14th October 13:05
Thanks for your comments GreenV8S, i fully agree!
The flow meter is situated close to the throttle as it would be on a standard TVR, i'm hoping that the large intercooler will "smooth out" any turbulent air before it hits the flow meter, also because the flow meter is in it's standard location throttle response will be the same as a standard car, maybe the throttle angle POT would compensate for this anyway? (Much in the same way as a pump-jet on a carb?)
The MSD 6BTM box takes it's signal directly from the magnetic pick-up in the standard rover dizzy, i removed the rover amplifier from the side of the dizzy and soldered the MSD trigger wires directly to the mag pick-up terminals. Because the MSD has a very high output to the coil (450v dc) you cannot leave the ECU trigger wire connected to the coil negative, so i used the MSD tacho output witch puts out a square wave P-P 12v at 20% duty cycle. This does mean that you have to open the ECU and make a small mod to allow the MSD to trigger it; if you need to know the details i will be more than happy to send them to you.
I paid $400 for the MSD including the coil, at the current exchange rate that's cheap! I also like the MSD because you can adjust the boost retard from inside the car in real time.
I think you can change the flow meter for a 4.6L item with a small wiring change??
Dale.
The flow meter is situated close to the throttle as it would be on a standard TVR, i'm hoping that the large intercooler will "smooth out" any turbulent air before it hits the flow meter, also because the flow meter is in it's standard location throttle response will be the same as a standard car, maybe the throttle angle POT would compensate for this anyway? (Much in the same way as a pump-jet on a carb?)
The MSD 6BTM box takes it's signal directly from the magnetic pick-up in the standard rover dizzy, i removed the rover amplifier from the side of the dizzy and soldered the MSD trigger wires directly to the mag pick-up terminals. Because the MSD has a very high output to the coil (450v dc) you cannot leave the ECU trigger wire connected to the coil negative, so i used the MSD tacho output witch puts out a square wave P-P 12v at 20% duty cycle. This does mean that you have to open the ECU and make a small mod to allow the MSD to trigger it; if you need to know the details i will be more than happy to send them to you.
I paid $400 for the MSD including the coil, at the current exchange rate that's cheap! I also like the MSD because you can adjust the boost retard from inside the car in real time.
I think you can change the flow meter for a 4.6L item with a small wiring change??
Dale.
Since you're using an intercooler between the compressor and the hotwire meter, I would guess this takes care of the temperature and turbulence issues. Still don't know enough about the hotwire characteristics to predict whether it will correct for the sort of pressures you'll be using. But since Paul and Mark Adams and others have done this before I'm sure they'll know the answer.
I asked the Omex technical guys about using the distributor as a crank position sensor. They said that with their system they strongly recommended using a crank position sensor. They gave me several reasons, but I don't know which ones were show stoppers and which ones were just awkward:
The vacuum/mechanical advance mechanism is not always consistent because there is usually play in it.
The Omex system (and presumably any other similar one) can only retard the spark not advance it, so it is necessary to advance the distributor to the maximum advance that is going to be used, plus a bit. In practice this means the rotor arm is in danger of missing the posts by the time the retarded sparks arrive.
If you lock off the mechanical advance mechanism to reduce the play then this makes the timing problem much worse.
I suppose that different makes might need more or less processing time so they might not all be the same, but I'm very interested to know how you get on with yours. I've added a timing wheel on the front pulley 'just in case' but it would be kind of convenient if I could get away with the approach you're using.
I asked the Omex technical guys about using the distributor as a crank position sensor. They said that with their system they strongly recommended using a crank position sensor. They gave me several reasons, but I don't know which ones were show stoppers and which ones were just awkward:
The vacuum/mechanical advance mechanism is not always consistent because there is usually play in it.
The Omex system (and presumably any other similar one) can only retard the spark not advance it, so it is necessary to advance the distributor to the maximum advance that is going to be used, plus a bit. In practice this means the rotor arm is in danger of missing the posts by the time the retarded sparks arrive.
If you lock off the mechanical advance mechanism to reduce the play then this makes the timing problem much worse.
I suppose that different makes might need more or less processing time so they might not all be the same, but I'm very interested to know how you get on with yours. I've added a timing wheel on the front pulley 'just in case' but it would be kind of convenient if I could get away with the approach you're using.
I did an emerald on a Chim 4 litre using the dizzy, welded the baseplate and cut a slot to rotate the rotor arm relative to the spindle .. no problems with cross firing even running large part throttle advances. it's all detailed in Dave Walker's handy little engine management book from haynes 
I'm with Dave on wednesday mapping a Cerbera if you want a signed copy
I'm with Dave on wednesday mapping a Cerbera if you want a signed copy
The MSD 6BTM ignition unit I’m using only retards the timing under boost pressure (it has it’s own internal 1 barg MAP sensor); the normal timing curve is taken care of by the standard distributor using the centrifugal advance weights, so the MSD must take it’s trigger from the distributor.
The vacuum advance system should still work in the normal way; I may have to put an end stop on the base plate to stop the vacuum advance retarding the timing under boost (something witch will never be required in a standard normally aspirated engine!) The free advantage to the MSD system is that you get a better combustion due to the Multi Spark Discharge – you get up to 7 sparks per fire depending on the available “time”, so at high engine RPM you may still only get one spark per fire.
Dale.
The vacuum advance system should still work in the normal way; I may have to put an end stop on the base plate to stop the vacuum advance retarding the timing under boost (something witch will never be required in a standard normally aspirated engine!) The free advantage to the MSD system is that you get a better combustion due to the Multi Spark Discharge – you get up to 7 sparks per fire depending on the available “time”, so at high engine RPM you may still only get one spark per fire.
Dale.
rottey said:
Hello v8dale
we know of over 50 rover v8 turbo engine mapped by Mr MARK ADAMS on 14CUX efi
Hope this helps
Paul(AUSTEC RACING LTD)
Paul,
Any idea how much power i can expect from my turbo'd V8? it's a 3.9L with TVR spec heads, 9.0/1 CR and a V8 developments MC1 cam? (The ecu is from a 4.0L TVR)Max boost i intend to run is 14PSI, max RPM 6K.
Cheers Dale.
Gassing Station | General TVR Stuff & Gossip | Top of Page | What's New | My Stuff