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MG MGB GT V8 Factory Originals Technical - fuel injection
|hi is there alot more work involved if you decide to go for fuel injection instead of a carb set up even if you have all the wireing complete with the engine thanks daren|
|I think it is less work than setting up carbies (about which i know very little, except that it was going to be much more expensive than fuel injection, for me).|
You need to buy the fuel injection style intake manifold which has all the fuel injection gear on it. You also need the air intake meter (which is sort of attached to the intake manifold anyway)
You need to get the trumpet tray in the plenum (air intake)welded and machined. You can't possibly do this yourself so Take it to a machine shop (engine reco' sort of place) and get them to weld up the three vacuum take offs on the left hand side. Tidy up the welds and then machine 15 or 16 mm off the bottom and up to 10 or 11 mm off the top. This cost me less than $100 to have done, so it's cheap enough. That should be enough to get it under the bonnet. If it isn't, you can get 5mm machined of the top trumpet cover. You also need to cut your trumpets down, depending on how much comes off the trumpet tray obviously.
You need to set up a high pressure fuel pump and a return line to the tank. You should not try to weld your fuel tank (KA-BOOM).
I got the extra line into the tank by using a very late model MGB fuel guage sender (this has an uptake line incorperated into it). Some of the early tanks have baffles, so you can't use the later sender. Those people effected usualy just put a return line into the existing sender, which you can remove to a safe distance to work on it.
I used a generic bosh fuel injection pump for the high pressure to the injectors($150). I fed this bosh pump with a "feeder" pump. made by pierburge part number 12001 ($100). I put a large filter just prior to the peirburge pump. As well as protecting the pumps (VITAL) this large filter acts as a surge tank and completly prevents fuel starvation in corners etc. Initialy I just put the two pumps and the filter in the boot. I have now tidied this away to a spare corner behind the rear wheel.
This took me an afternoon to set up. A hose clips and plyers sort of job.
The peirburge pump is necessary because the bosh high pressure pump can't effectivly suck petrol through any sort of filter. Cavitates noisily. The peirburge pump sucks very well and can keep up with the bosh pump. You can't get a pump that both suctions well and delivers high pressure.
Some people do a variation and use an external swirl pot, that has a high pressure a bosh pump underneath. A kind of douple loop set up. Obviously you still need two pumps. Some people buy a new tank and weld in an in tank pump attachment point.
Electrics- easy- The Rover/range rover is a stand alone set up. A wire to power the computer. A wire to the ignition. A wire to the fuel pump(s). A wire to the coil.
depends upon the carb you want to use...
For EFI you'll need a different pump, additional fuel line, modified tank, EFI wire loom, additional fliter and checkalve. Bonnet clearance will be very critical with the stock Rover system too.
Using the Edelbrock(Weber USA) carb, setting this is very easy as it is with a Holley 390 although the Holley will be the more expensive solution when all the necessary bits have to be bought to make it a perfomance part for the MG-B. It is also more time consumpting than the Edelbrock concerning the FIRST setup/tuning process and you should go to bed with the Holley cataloge several times.
Using a Carb on a MG-B V8 keeps things much more simple and servicable for DIY than it will be with EFI although it is not an easy job to add a catalytic converter to a carb system but very straight forward with EFI if this is your target too.
|Sounds like you have a wrecked or rotted RV8 for a donor car. If so, then keeping the same systems the RV8 used in a MGB body shouldn't be difficult, just remember to keep the engine wiring harness intact and mofify the MGB as necessary for the correct fuel system plumbing. When dealing with any type of fuel injection you are most likely dealing with some type of computer, usually digital in nature. If you have a basic understanding of the inputs necessary for the device and make sure you duplicate these inputs in the new car, then conversion shouldn't be too much of a problem.|
Geoff (King) and I found no difficulty in fitting EFi.... loads of hot-wire kit on E-bay, plenty of info on the 'official' MGOC BBS, also V8 forum.
Plumbing and wiring are pretty straightforward, much more economical than carbs, and never needs re-tuning.
Go for it mate !!
|The amount of learning invovled with FI may be greater - or you can just farm the wiring harness out to one of the businesses that modifies them and get back a plug and play harness and ECM suitable for your car, for similar cost to buying manifolds and carbs.|
One thing isn't in doubt - the injected car will start and run better and probably get better mileage as well as polluting less.
I've done many cars with carbs but did my latest MG project with FI and prefer it.
I don't know which engine you are looking to go with. I used the GM 3.4L crate. I used the Edelbrock Torker manifold. Bill guzeman sells or will shorten your plenum for hood clearance.
I used The Holley 950 Comando Fuel TBI Fuel injection. Great Great set up. Easy to install. Easy to program with laptop. I have even started it in 30 degree weather with no problem.
The advantage to a package deal over robbing one off a factory car is it is designed for you to work with a laptop to make any change you need. No hacking. Dissadvantage is Wires. Lots of wires.
Here is my build:
This thread was discussed between 15/02/2007 and 19/02/2007
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