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Any of you guys know if a 4.0 or 4.6 can be converted to carburettors and if so what parts can be used from previous models of V8 ? The engine is to be used in a Super Banger so I’m looking to simplify the running of it ie no ecu to rattle when taking a hit ! The rules do allow for fuel injection to be run but the electronics scare me ie cutting out after a hit or do you think it would be fine ? I’m guessing that comp safari guys still use the ecu ? 
 

Any help would be greatly appreciated 

cheers in advance , James 

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9 minutes ago, FridgeFreezer said:

Your biggest issue is no distributor - you can run the early front cover & inlet etc. I think you just need a spacer for the crank bolt - I used to run mine like that using all the bits from an old 3.9.

Ahhhh , I forgot about your 109 , so how do you run it now ? 
🤦🏼‍♂️ Just remembered, it’s mega squirted now isn’t it ?

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1 minute ago, Ozzy50 said:

Will watch that when I’ve fed my 10 baby pigs their bedtime milk 👍🏻

That's a perfectly normal sentence.

I'll be honest, I haven't watched it - I just know the guy is doing it and he might talk about what it needed  to convert here, or one of his other 4.6 videos. At least it shows not just that you can, but that someone evidently thought it was worthwhile enough to actually do.

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15 minutes ago, Ozzy50 said:

Ahhhh , I forgot about your 109 , so how do you run it now ? 
🤦🏼‍♂️ Just remembered, it’s mega squirted now isn’t it ?

Yep it's been on MSEFI for <cough> knocking on 2 decades now :blink:

The 3.9 went Holley, Weber, Flapper EFI and then MSEFI in 2004, switched to 4.6 and MSEFI+EDIS in ~2007.

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19 minutes ago, Bowie69 said:

Your biggest issue will be plummeting power, torque, fuel consumption and drivability -but don't let that stop you....

Fuel consumption not an issue , power , torque and driveability is ! Do you think the ecu would be up to the job in a contact race formula ?

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I have a 4.6 on carbs pending the installation of EFI in due course.  I am running edis at the moment in default mode for ignition and works OK but have mega jolt to go on and then when converted to Efi it and edis will go.  If you are going to run an older timing cover with a dizzy then as discussed above.

Issues you need to look at - the old 3.5 etc has a rear filtered air intake at the back of the block that allows air into the crankcase - this is sucked into each carb via the outlets on top of the rocker covers.  The 4.6 does not have this rear block inlet so I have the crankcase air inlet as the original crankcase breather on the passenger side with a filter and plumbed the drivers side into both carbs.  So crankcase ventilation goes in the passenger rocker cover, into the crankcase and out the drivers rocker cover (with flame trap fitted) into both carbs but one will be probably be good enough.

The other issue is the thermostat - through the cows udder style on the standard 4.0/4.6 and use the standard system on front of the carb.  If you use a dizzy timing cover the thermostat bypass is not an issue but if you go without a dizzy and use a 4.0/4.6 timing cover you will need to sort this - as an interim measure I have just drilled a few small holes in the thermostat which works but I do need a better plumbed solution - just a pipe from the thermostat housing to the lower radiator hose.

You can tune carbs for power, fuel and torque, afterall the injected 4.6 with about 160kw is not power house.

 

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Why what would affect a carb?

I run a std 3.5 on carbs  problems were from the dizzy being old, starting and running issues. Put on EDIS and MegaJolt runns fantastic now. Doesn't like flat battery when starting as the power goes to the starter not the MJ.

EFI if you have an impact sensor it will cut out when you impact another vehicle as that is what it is designed to do. MegaSquirt its up to you if you fit the sensor.

 

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1 hour ago, missingsid said:

EFI if you have an impact sensor it will cut out when you impact another vehicle as that is what it is designed to do. MegaSquirt its up to you if you fit the sensor.

Takes a BIG impact to trigger the fuel cut off switch, us very easy to wire out or cable tie into the 'on' position.

9 hours ago, Ozzy50 said:

Do you think the ecu would be up to the job in a contact race formula ?

Don't see why not,  they are designed to be rattled around inside vehicles all their life.

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36 minutes ago, Bowie69 said:

Takes a BIG impact to trigger the fuel cut off switch, us very easy to wire out or cable tie into the 'on' position.

I was going to say that banger racing is a big hit, however if found this comment.

 

You don't get a lot of the heavy hitting contact in this formula, cos although the cars are built to last they arent easily straightened out after a big hit.

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All good stuff guys , thank you , tbh it’s a friend who is trying to talk me out of running the efi as he thinks it will be fragile but I hadn’t ruled it out , there is a 2.3 duratec in the formula that runs the standard efi and as @missingsidsays the hits aren’t (usually) massive , no follow ins etc. 
@garrycol , thermostat not a problem as it won’t b running one. 
thank u all for your input 👍🏻

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1 hour ago, Ozzy50 said:

@garrycol , thermostat not a problem as it won’t b running one. 
 

Yes but you will still need the housing to connect the radiator hoses - if a 4.6 ditch the cows udder arrangement and fit an old 3.5 housing and if not running a thermostat then just block the thermostat bypass outlet.

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5 hours ago, elbekko said:

The float being launched and causing overfuelling. Shouldn't be too much effect as it'll only be momentary, but still.

I believe the early Merlin engines used to have an issue like this in negative-G situations.... Useless fact for you.

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1 hour ago, ThreePointFive said:

I believe the early Merlin engines used to have an issue like this in negative-G situations.... Useless fact for you.

Yup, whereas the Messerschmitt BF109 had direct fuel injection, so didn't suffer the same fate.... telling?

More useless info....

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1 hour ago, Bowie69 said:

Yup, whereas the Messerschmitt BF109 had direct fuel injection, so didn't suffer the same fate.... telling?

More useless info....

Not sure you can drive a car upside-down even an F1 is hyperthetical.

 

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I found the carbs were affected by angles - the Holley hated climbs / descents and the Weber hated side-slopes... fundamentally carbs rely on moving parts, EFI doesn't unless you count the needle in the fuel injector or the impeller in the fuel pump.

The inertia switch is purely a thing added on by manufacturers for safety, ECU's don't care if they're there or not and they're not exactly dark magic. MS doesn't use one, although you could wire one in if you really wanted to of course - just like you can add electric fans or NOS or launch control if you want...

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5 minutes ago, FridgeFreezer said:

I found the carbs were affected by angles - the Holley hated climbs / descents and the Weber hated side-slopes... fundamentally carbs rely on moving parts, EFI doesn't unless you count the needle in the fuel injector or the impeller in the fuel pump.

Don’t disagree, although I suspect it would depend on exact setup and use. I’ve done a lot of RTV trials with a factory 3.5 RV8 running stock twin Stromberg carbs. And it has never missed a beat off road. Not that I’d recommend that setup for max power, but not all things are about the biggest numbers :D 

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1 hour ago, Chicken Drumstick said:

I think it wad the Engine Masters series they did some EFI vs Carb shout outs. The carb motors often made the most Peak numbers.

Yes, I saw that episode, however it was just peak, elsewhere it was a slightly different story.

I think they put the difference down to the charge cooling effect of the fuel evaporating in the carburettor throat,  whereas the EFI being right up against the port didn't quite have the same time to have as much of an effect.

I'd still go EFI over carbs any day.

Though an SU'd a-series is a lovely drive ;)

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Thank you everyone for your input , I’m feeling quite confident that retaining the efi will be perfectly acceptable. Does anybody know if the engine ecu for the 4.6 is stand alone ? I’m guessing there is the immobiliser to sort / remove but is there anything else ? 
Again cheers in advance, James 

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