ECU upgrade for flapper system?

[JMF894]

Hi there. As i understand it the hotwire system is more tuneable than the flapper system with regards to an aftermarket chip such as a Mark Adams Tornado chip. Am I correct in this assumption?

My local specialist made a comment last month when he was telling me that my car was running rich on start up saying......." running rich can cause excessive engine wear over time (fair enough)............. some of the aftermarket tuning ecus such as Mark Adams run the engine rich to create more power"

I have taken these comments a little out of context, however, two questions:

1) Is there an aftermarket tuning chip available for the flapper system?

and, if so:

2) Is running the engine richer simply a bad idea and is more cc the way to go for more bhp?

For the record I have a 1989 450se.

Would I simply be better off getting the car on a rolling road and ensuring that what I have is running at optimum?

Cheers in advance Jimbo

[Number 7]

I slung my flapper 10+ years ago, and went fully programable fuel and ignition. I'm really not sure what tweaking options there are for the flapper, and whatever they are, they would probably be fairly crude. Yes, I believe that you can get chips for the hotwire system. Ideally they would need to be mapped for your car though. Could be expensive by the time you've bought an ecu, AFM, injectors, fuel rail etc. and you still don't have programable ignition. I'd get the car onto a rolling road first, and see what it's making, and what the AFR is like. Then if it's a lot out that can't be easily sorted, consider something like Emerald. BTW, try disconnecting the cold start injector and see how it runs.

[v8 racing]

Number 7 said:

I slung my flapper 10+ years ago, and went fully programable fuel and ignition. I'm really not sure what tweaking options there are for the flapper, and whatever they are, they would probably be fairly crude. Yes, I believe that you can get chips for the hotwire system. Ideally they would need to be mapped for your car though. Could be expensive by the time you've bought an ecu, AFM, injectors, fuel rail etc. and you still don't have programable ignition. I'd get the car onto a rolling road first, and see what it's making, and what the AFR is like. Then if it's a lot out that can't be easily sorted, consider something like Emerald. BTW, try disconnecting the cold start injector and see how it runs.

Suan from v8d soddy on here has done a plug and play fully mapable fuel and spark for the flapper system, maybe worth giving him a shout

[honestjohntoo]

JMF894 said:

I have a 1989 450se. Would I simply be better off ---------- ensuring that what I have is running at optimum?

Your 450 Flapper must have come out of the showroom with well over 200 horses under the bonnet! If you are disappointed, could it be that some of them are being a tad lazy? With all those potentially bigger bangs (compared to a 200 bhp 350 for example), you might consider making sure that the absolute minimum of power is LOST.

Getting the absolute best out of your engine cannot be achieved in one go, but addressing each part, bit-by-bit, until there are no unnecessary losses is relatively straight-forward DIY process. One has to start with the premise that the engine is in good mechanical condition with correct cam/lifter performance and timing, good compression within acceptable limits on all eight cylinders, good exhaust system with no leaks and fresh engine lubrication plus new filters if required, then, although I'm not au fait with your particular engine, this 15 step program should be readily adaptable to your larger capacity flapper system, to change or improve performance from its current condition.

1 Clean all ignition components externally and internally (where possible), spray with moisture inhibitor such as WD40 and wipe dry. If fitted, make sure the distributor vacuum/mechanical advance systems are working correctly.

2 Check security and eliminate any corrosion on all ignition LT connections right back to the ignition switch, including local earths.

3 Clean and re-gap the spark plugs - replace if necessary.

4 Check for damaged or out of spec (measure suppression resistance) HT leads, clean and replace if necsssary.

5 Set up ignition timing to just eliminate pinking with your chosen fuel. (Note: Items 1 thro 5 are to guarantee and maximise the best possible spark at exactly the right time, always.)

6 Ensure that the plenum idle air gallery or idle control system is clear and not contaminated with goo.

7 Likewise the plenum breather gallery, flame trap and LH rocker cover breather filter. Also check rocker cover gaskets are not breached.

8 Ensure the throttle disc is correctly seated at idle (or set to the recommended disc/tunnel gap) to prevent idle speed hang-up and that the whole throttle mechanism is free of unwanted friction right thro' from accelerator pedal to throttle pot. (Note - items 6, 7 and 8, Plenum actions, are best done on the workbench).

9 If applicable, set the CO content to the recommended range, just erring on the weak side of the mid point and likewise, if possible, reset the idle speed to the recommended level.

10 Set the throttle pot residual voltage to 325 millivolts or what your Efi spec calls for - sometimes 350mv. Make sure the pot is not electrically noisy, causing random overfuelling.

11 Check your fuel pressure is operating in the recommended range for your engine (typically 26 to 36 psi for a 350, but probably something like 36 to 46 psi for a 450)

12 Check the integrity of the plenum and all its air/vacuum hoses for rogue air-leaks.

13 Check all Efi loom wiring/connections for faults/corrosion including the Efi engine earth AND the engine earth strap.

14 Check and replace fuel filter if necessary (also make sure the fuel tank is not delivering any crud).

15 Because the Plenum really has to be removed for proper cleaning/adjustment, lift and clean the injectors at the same time, replacing the filter baskets and pintle caps.

You may be tempted to skip some items, assuming that things are actually OK. Unless you KNOW - assume nothing! None of the above will add anything over and above the engine performance that existed when it was new but you'll be amazed at the horses the above suggestions can release from tired and maladjusted Electronic Fuel Injection systems and the beauty of it is that, apart from time, the majority of these actions are cost free.

Unsure how any of the main Flapper components function and what adjustments may be available to you? If Yes, CLICK here to check out this archive

Edited by honestjohntoo on Wednesday 6th July 23:05

[JMF894]

Wow! Thankyou so much for taking the time and effort to make such an in depth and informative post

Firstly I am not dissappointed with the performance of my 450. It feels quicker than my previous 400. Apart from perhaps running a bit rich on start up it runs very well and feels quick. It has lots of history including refurbished heads and a new cam. However.............

I think after reading your post the common sense approach is to make sure what I have is running properly. TBH a 10bhp gain on a car as light as the wedge would feel

Much food for thought. My first step next month will be to get the car on the rolling road to see whats what and I will go from there. I am no mechanic so some of the points you have made will require some focus for me!!

Many many thanks again, I have saved this page for reference.

Jimbo

[Mike Brewer]

Hi i have to agree with you.i read the write up many times.When trying to understand my recent problems,Brilliant stuff.CheersMike

[adam quantrill]

Ramon, if I might be so bold, your list plus item zero (at the very front): the number one rule of tuning:

0: When you press your foot hard on the accelerator, does the throttle open fully? This might be a two-man job to check (or use a stick wedged against the seat.)

[pwd95]

My old 450SE Flapper made 283bhp on the rollers at last years BBWF. Just a matter of tweaking the fuel pressure on the flapper. Quite crude compared to later systems. There is an adjustable ECU available for the flapper. Had one on my 350i/450 conversion. It had a dial on the side that basically adjusted the reading from the coolant temp sensor to fool the ECU to make it richer or leaner. Again quite crude but if set up on the rollers to give a good AFR reading during full throttle, quite effective...................

Edited by pwd95 on Thursday 7th July 00:11

[grahamw48]

adam quantrill said:

Ramon, if I might be so bold, your list plus item zero (at the very front): the number one rule of tuning:

0: When you press your foot hard on the accelerator, does the throttle open fully? This might be a two-man job to check (or use a stick wedged against the seat.)

Adam you are so right.

A couple of weeks ago I accompanied my young friend to a rolling road so that he could get the engine on his recently body-off re-built 2.9 S series set up and running right.

Imagine his disappointment when on the first run it showed a mere 99bhp at the flywheel!

This on a car that had a re-built engine that seemed to run really sweetly.

The operator discovered that the throttle wasn't opening fully, because of a poorly connected linkage.
Also a piece of gasket or similar was partially obstructing the AFM.

Second run....172 bhp. 4 more than TVR claimed.

[daxtojeiro]

JMF894 said:

Hi there. As i understand it the hotwire system is more tuneable than the flapper system with regards to an aftermarket chip such as a Mark Adams Tornado chip. Am I correct in this assumption?

My local specialist made a comment last month when he was telling me that my car was running rich on start up saying......." running rich can cause excessive engine wear over time (fair enough)............. some of the aftermarket tuning ecus such as Mark Adams run the engine rich to create more power"

I have taken these comments a little out of context, however, two questions:

1) Is there an aftermarket tuning chip available for the flapper system?

and, if so:

2) Is running the engine richer simply a bad idea and is more cc the way to go for more bhp?

For the record I have a 1989 450se.

Would I simply be better off getting the car on a rolling road and ensuring that what I have is running at optimum?

Cheers in advance Jimbo

The AFR required during warmup can vary a lot between engines. How rich is rich? You could simply just not push it (meaning it will run rich) until its warmed up. If its AFR is all correct when its warm then you have got the flapper as good as it will get. Adding fuel isnt the answer, if its running at 12.5ish when your WOT and warm, then your as good as it can be. The flapper AFM restricts the air a fair bit, reports of 10% have been claimed, so maybe an aftermarket ECU is the way to go. V8D sell them for the flapper (Plug-N-Play) this allows you to dump the AFM.
The main gains would come from a fully mappable ignition and fuel setup. Again V8D can help you there if you need a PnP setup. This is where youll really notice the difference between an old flapper and a fully mapped setup.
I wouldnt bother just changing over to a hotwire from a flapper, you will have a better setup, but its still going to be lacking ignition control and you will struggle to get it mapped for fueling your engine,
cheers,
Phil

[ROOODBOY]

I'm reading this thread with interest, as I plan on ditching the flapper AFM on my 350I, perhaps later in the year.

I don't wish to put down any of the suggestions regarding aftermarket ECUs, I'm sure they can work very well, but it seems to me that a hotwire set up including wiring and ECU can be had from an old Range Rover or such like for very little cash, but an aftermarket ECU is going to be the thick end of £1,000 or more, once it's fitted and mapped.

So my question is, upgrading where a budget is very tight, is hotwire a feasable and worthwhile upgrade if parts could be sourced for a couple of hundred quid or so?

Thanks,

Martin.

[pwd95]

ROOODBOY said:

I'm reading this thread with interest, as I plan on ditching the flapper AFM on my 350I, perhaps later in the year.

I don't wish to put down any of the suggestions regarding aftermarket ECUs, I'm sure they can work very well, but it seems to me that a hotwire set up including wiring and ECU can be had from an old Range Rover or such like for very little cash, but an aftermarket ECU is going to be the thick end of £1,000 or more, once it's fitted and mapped.

So my question is, upgrading where a budget is very tight, is hotwire a feasable and worthwhile upgrade if parts could be sourced for a couple of hundred quid or so?

Thanks,

Martin.

There are quite a few hardware differences with different plenum chamber, fuel rail, bits & bobs like that. All salvagable form an old Rangey I suspect.

[ROOODBOY]

pwd95 said:

ROOODBOY said:

I'm reading this thread with interest, as I plan on ditching the flapper AFM on my 350I, perhaps later in the year.

I don't wish to put down any of the suggestions regarding aftermarket ECUs, I'm sure they can work very well, but it seems to me that a hotwire set up including wiring and ECU can be had from an old Range Rover or such like for very little cash, but an aftermarket ECU is going to be the thick end of £1,000 or more, once it's fitted and mapped.

So my question is, upgrading where a budget is very tight, is hotwire a feasable and worthwhile upgrade if parts could be sourced for a couple of hundred quid or so?

Thanks,

Martin.

There are quite a few hardware differences with different plenum chamber, fuel rail, bits & bobs like that. All salvagable form an old Rangey I suspect.

Yes, I have heard that the plenum, inlet and fuel rail are different.


I'll be honest now, a couple of weeks ago I bought a 3.9 Range Rover engine complete with injection gear, wiring, ECU, hotwire AFM etc., all for £230, I'm now considering my options as to what is worth doing with it all.

Thanks.

[grahamw48]

Ditching the flapper will lose you that lovely popping and banging.

I know it's supposed to be possible to 're-create' the effect when using more modern systems, but I remain to be convinced.

I've had two flapper cars (both 390s) and a hotwire 400SE.

Even after the 44,000 mile with new cam hotwire had been properly set up on a rolling road, I'm convinced it was slower than my first 390 flapper, and of course no pedestrian-scaring noises, which personally I really missed.

The engines in V8 Wedges seem to be so variable in performance between individual cars, that I would first ensure that every area of the engine and its ancillaries was up to par before junking anything.

The only advantage I could see of the hotwire was that it appeared more economical by 2 or 3mpg, which would take an awful lot of runs out to recoup the hundreds spent on 'upgrading' to hotwire though.

[rev-erend]

Guys .. never ditch the flapper for a 14cux.

The noise is fantastic.

Newer systems are capable of flapper style noises and have multi map ability
so you can switch to a fuel saver map but it will cost north of 1K to get it up and running right. Thats a lot of money on an old car.

[ROOODBOY]

rev-erend said:

it will cost north of 1K to get it up and running right.

This is my problem!

[soddy]

There are obviously many schools of though out there and I would not want to 'discourage' an enthusiast .. but I have to say that the 'upgrade' from Flapper to Hotwire is a real non starter! To be honest the Hotwire is no more 'tuneable' than the flapper, yes it may be able to cope better with changes in air density because it uses an air mass meter as opposed to a 'Flap', but lets be honest, the engine is more than capable when controlled by throttle angle alone, as long as the map is good! If you can afford it and want a 'good' upgrade, then go for an aftermarket version .. the Megasquirt can be done in a plug and play format format for the flapper, so no need to change the loom or any wiring, it can be a fuel only upgrade as well if you want it that way and I think I am right in saying that costs about £700 all in. But if your budget is tight .. then just get someone who knows what they are doing to set up the Flapper, it will not be perfect in all conditions but it will still be pretty good.
Good Luck!

[JMF894]

soddy said:

There are obviously many schools of though out there and I would not want to 'discourage' an enthusiast .. but I have to say that the 'upgrade' from Flapper to Hotwire is a real non starter! To be honest the Hotwire is no more 'tuneable' than the flapper, yes it may be able to cope better with changes in air density because it uses an air mass meter as opposed to a 'Flap', but lets be honest, the engine is more than capable when controlled by throttle angle alone, as long as the map is good! If you can afford it and want a 'good' upgrade, then go for an aftermarket version .. the Megasquirt can be done in a plug and play format format for the flapper, so no need to change the loom or any wiring, it can be a fuel only upgrade as well if you want it that way and I think I am right in saying that costs about £700 all in. But if your budget is tight .. then just get someone who knows what they are doing to set up the Flapper, it will not be perfect in all conditions but it will still be pretty good.
Good Luck!

Yes my next step with the 450 is to simply ensure what I have is running at its best. I know so little about these cars and what's out there at the moment I feel a little bemused by all the different opinions(but very grateful for them!) at present. Please keep your views coming. I think this is a really good thread.

But I may be biased

[ROOODBOY]

I apologise for the slight thread hijack, but it is kind of on the right topic!

[honestjohntoo]

JMF894 said:

I know so little about these cars and what's out there at the moment I feel a little bemused by all the different opinions

Given your starting point of not knowing too much about Efi systems, and bearing in mind that you currently have a good working Flapper system (that at worst - may need a bit of fettling to get it running 100% tickety-boo) then your best bet is indeed, to stay with what you have, read everything that is readily available, and initially rely on the broad base of Flapper knowledge that exists on the web and the associated RV8 forums.

You will be on a journey of discovery, sure, but this is not rocket science and as I say, there is plenty of help available - "flapperwise!".

Also, because you are in a learning phase, spend your time and small amounts of money in studying and understanding what you have. Don't mess with it - Study it!

Yup, you could go to hotwire or megasquit, it'll cost ya, it'll put the car out of action during the transition, depending upon who you choose to do the work - it may even get badgered, and you may find there is less depth of expertise available when it comes to the crunch and you need a local Norfolk buddy.

Regarding the power available, you may have to ask yourself if any extra power and flexibility of tuning from an alternative system is really gonna be useful in todays motoring environment.

From some of the comment on this thread already, it seems that some aspirations are simply to indulge in the "noise" factor, when in all probability, unless you are rolling in moolah, the most one can hope for these days is a pleasurable motoring experience on any available open road - plus whatever noise you choose to invoke!

Being's as where you are - Norfolk - you've probably got the best of what's available in the country for the odd burst of power along deserted country roads at midnight by a full moon. Lubbly Jubbly.

Edited by honestjohntoo on Thursday 7th July 21:51