Rom box? What is it?

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Oxfordshire
I was talking to a bloke at the pub last night (I know this is a dangerous place to start any sort of car chat, but he piqued my interest) and he mentioned there was a way to vastly improve the mpg of the Freelander 1 TD4 with something he called a rom box. Said it was easy to fit and an instant improvement.
I took his word for it and Googled it when I got to work this morning and I can't seem to find anything whatsoever.
The only thing I'm thinking is that he meant replacing the computer chip. Unless there is such a thing as a rom box, I got the impression he meant it to go on the gearbox, but as I say, man in the pub is not a reliable source.

If a new control chip is what he meant, are the advantages worth the outlay? Will it affect things like towing (often pull a small horsebox or caravan).

Thanks,

Mark
 
I had one in my early freelander ownership 2002/3 and would not have another one as all it did was put more fuel into the engine but I may be wrong with the ron boxes
 
I had one in my early freelander ownership 2002/3 and would not have another one as all it did was put more fuel into the engine but I may be wrong with the ron boxes

You are not wrong more power more torque more fuel simples. You may get slightly better fuel figures on a long steady speed run on a motorway but that is all. Use the power use the fuel. Anybody that says fitting a tuning chip gives better fuel consumption for every day stop start driving is talking through their arse.
 
I seriously considered putting one of these devices on my Freelander for quite some while. Having read into it however and listening to other members here, I came to the conclusion that more power was likely to come from increasing the fuel pressure and thus putting more load on the pump. I really think you get better less risky results by good servicing, good driving, an EGR bypass and keeping everything nicely sealed, maybe with silicone hoses. My FL1 did 40.5 mpg on a return trip to Northumberland recently with no more modification than that. Hope this helps. If I'm talking through my arse, someone say so!
 
I can't see how adding a Ron box will damage the HPFP. The pump is still going to deliver the same pressure regardless of what modification to the engine or its controls. If anything, the actual rail pressure should drop slightly on full throttle because more fuel is fed into the engine to be burned.
I've read about HPFP failure after Ron box fitment, but saw no real evidence that the RB was the actual cause.
In simple terms, the HPFP could have been just about to fail anyway, weather a Ron box was fitted or not.
The way these boxes make more power, is by adding more fuel. The HPFP is turned by the engine to pressurise the fuel rail. The faster the engine turns, the higher the pressure. The sensor is there to monitor the rail pressure so the ECU has a basis on which to make fuelling calculations. The Ron box, in simple terms fools the ECU into thinking that the fuel rail pressure is lower than the actual figure. This way the ECU compensates by adding a bit more fuel. The pump doesn't make more pressure to add more fuel. It's always going to make more than the engine could ever use. This is why I don't believe HPFP failure is attributed to RB fitment.
 
I seriously considered putting one of these devices on my Freelander for quite some while. Having read into it however and listening to other members here, I came to the conclusion that more power was likely to come from increasing the fuel pressure and thus putting more load on the pump. I really think you get better less risky results by good servicing, good driving, an EGR bypass and keeping everything nicely sealed, maybe with silicone hoses. My FL1 did 40.5 mpg on a return trip to Northumberland recently with no more modification than that. Hope this helps. If I'm talking through my arse, someone say so!

Nothing to do with fuel pressure, it is about fuel quantity for any given throttle opening. Extra fuel is injected within the confines of the map it is the only way to increase power and torque.
 
Ah! I WAS talking through my arse! Good explanation, thanks, Nodge.
Not necessarily. There is a lot of information out there on HPFP failure and the Ron box. The problem is, there's no way to tell if the HPFP was about to fail before the RB was fitted. To counter those claims, how about this angle. The owner felt the engine was sluggish, possibly due to a failing HPFP. So a RB was fitted and power was restored, or increased over the new power output. Now the owner loves the newly found performance and uses it. Revving the engine up much more than they previously did. This accelerates the wear on the HPFP, which fails in a few thousand miles.
Now the RB is blamed for breaking the HPFP, when it wasn't far from failure anyway. ;)
 
Would you at least agree that it's best to put the rest of the vehicle in as good a state as possible before fitting a tuning box?
 
Would you at least agree that it's best to put the rest of the vehicle in as good a state as possible before fitting a tuning box?
Of course I would. I'd go as far as to test the output pressure of HPFP and LPFP. The MAP sensor also needs to be in good health and the engine needs to be cleaned of gum from EGR operation.
Once these are done and all results satisfactory, then sure, fit a RB. Once the engine is running at a higher power level, the oil needs to be changed more often as it will degrade faster.
 
Brilliant, thanks for all your input guys. I am happy with the performance of the freelander as it is, all i was thinking was an increase in fuel economy, looks like my best bet for that is to settle my left foot a bit.
 
I've heard some good things about Ron boxes on the MG/Rover forums and for what they cost they do provide some improvement in power ( can't comment about mpg though) but personally although it would cost more ( about £350) , I believe a custom remap from a proven and reliable remap specialist would be better as this would optimise the both the fueling map and boost pressure and remove some factory limitations so that everything in the engine would be singing from the same hymn sheet so to speak instead of just upping fuel pressure
 
I've heard some good things about Ron boxes on the MG/Rover forums and for what they cost they do provide some improvement in power ( can't comment about mpg though) but personally although it would cost more ( about £350) , I believe a custom remap from a proven and reliable remap specialist would be better as this would optimise the both the fueling map and boost pressure and remove some factory limitations so that everything in the engine would be singing from the same hymn sheet so to speak instead of just upping fuel pressure
This might be worth thinking about then. To be fair, I get around 30mpg as it is, which is not to be sniffed at for sure, and performance wise it's not bad really. Obviously it's not rocket, but I don't get left standing as often as I thought.
 
This might be worth thinking about then. To be fair, I get around 30mpg as it is, which is not to be sniffed at for sure, and performance wise it's not bad really. Obviously it's not rocket, but I don't get left standing as often as I thought.
If all your driving is around town and its an auto - then 30mpg might be expected, but in general you'd want a diesel to average a lot more than that.
 
If all your driving is around town and its an auto - then 30mpg might be expected, but in general you'd want a diesel to average a lot more than that.
My TD4 auto does about 27Mpg on my daily commute, which consists of 14 miles of open countryside roads. Something else for me to investigate I guess.
 
I've heard some good things about Ron boxes on the MG/Rover forums and for what they cost they do provide some improvement in power ( can't comment about mpg though) but personally although it would cost more ( about £350) , I believe a custom remap from a proven and reliable remap specialist would be better as this would optimise the both the fueling map and boost pressure and remove some factory limitations so that everything in the engine would be singing from the same hymn sheet so to speak instead of just upping fuel pressure
The Ron box can't up the fuel pressure as the pump is a mechanical device connected to the engine. What the RB does in simplified terms, is to fool the ECU that the fuel rail pressure is lower than it actually is. The ECU then calculates the fuelling requirements based on a this lower rail pressure. This is basically how more power is made. The RB is a well designed box of tricks that does what it says on the tin.
 
The Ron box can't up the fuel pressure as the pump is a mechanical device connected to the engine. What the RB does in simplified terms, is to fool the ECU that the fuel rail pressure is lower than it actually is. The ECU then calculates the fuelling requirements based on a this lower rail pressure. This is basically how more power is made. The RB is a well designed box of tricks that does what it says on the tin.

Well it does in an indirect roundabout way via the ecu :p I was just simplifying things a bit too much lol

But agree very clever bit of kit for what it cost and if I was short on cash I would prefer a ron box to an ebay resistor any day of the week but personally i would prefer a remap more so to remove factory restrictions put in place for noise and emissions than anything else
 
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