EFI (Engine management)

First, I'm not that knowledgeable on the maping and just how it's don, I'm working with Hamilton Engendering that burns the chip and can furnish any part of the system for $$$. The system that will really shin as far as economy is concerned is the Multi port, which is one step above the TB system. In an effort to find an inexpensive system to replace the present systems on our Flathead s, I feel the ignition system is the most important. This can be programed to give any curv you can dream up. You can also modulate the output of the MAP sensor to add or subtract advance while driving. At present the only ignition system that meets today driving conditions is the 8bA style using an MSD or one of Bubbas modified distributors. These allow the tailoring of the curves to match the engines application.
Now here's the present plan, I'm using the ignition part of the EFI system and the stock carb. I agree the carb is not the major problem, but the ignition systems available for the pre 49 flatheads does not meet today's needs. Besides a poor advance curve, the components are becoming hard to find. Points and capacitors especially. Even the chevy points and caps have caused Richard and I problems. Filing a junk set is often better than the local aftermarket one.
Most of the 88-82 GM computers will operate the ignition only system and are a dime a dozen. Only the -47 is useful for a V8 and a TB at that. Now if you could replace your intire ignition system on you 32-48 ford for just a coupla hundred bucks and never have to look at it again, would you buy it. Especially when no one looking under the hood would know you had it.
 
Ok Ron , lets burn some brain cells here .

If ya take a 350 CI engine with Tbi ( throttle body injection) and the same engine with tuned port and run the test at 3000 rpm they both will require the exact same amount of fuel.....x amounts of mils of fuel....

The only change would be the torque curve on the way up to 3000...
Just some more fuelish thoughts...rbg :>)
 
The only difference I can see between a TBI and a Multi port injection is the economy angle. TB have a wet manifold. Multi port is a dry intake. The information I have says GM went to this to improve emissions and mileage. Your right about power. Also the sequential isn't much better than the tuned port except for emissions and economy. It's also possible to run an AF of 15.5 with the TB system. I gota feeling programming will be a *****.
 
You are on the right track Ron,my boy has a home made system on his car,he used a bought in controller,made his own manifolds and crank trigger act,
when it was on the dyno ,they needed to change the IGN timing,I,m getting the tools ready and in two secs they had it done on the laptop.
VERY nice,controls the fuel and IGN,but pricy.
Lawrie
 
BUBBAS IGNITION said:
Ok Ron , lets burn some brain cells here .

If ya take a 350 CI engine with Tbi ( throttle body injection) and the same engine with tuned port and run the test at 3000 rpm they both will require the exact same amount of fuel.....x amounts of mils of fuel....

The only change would be the torque curve on the way up to 3000...
Just some more fuelish thoughts...rbg :>)
Click to expand...

That would surprise me, an engine fitted with one injector per cylinder, squirting at the back of the intake valve surely has a more precise use of fuel than a single injection unit back up the intake manifold? Don't they? Isn't this one of the advantages of multi port injection?
Aside from that point, and to follow your comment about the torque curve up to the test rpm. I think we're talking about driving the engine up the road, not just under dyno condition steady state fuel use. On the road the multi point should win easy over single point, in every way.
I'm not arguing, I'm trying to understand this efi stuff, I'm a carburetor guy, never been that impressed with this efi stuff, when compared with good carb or carbs.
Martin.
 
It's hard to beat a carburetor set up for performance. For economy, it's a different story. It also somewhat impressive how clean the oil stays with a decent fuel injection set up for economy. Now if you set up an injection system for performance, you will likely see a lot of the dirty combustion products come back due to the richer AF mix. A person will also see the higher wear & tear factor come back as well. Higher compression & valve lift/duration is a big factor for performance too but the little flatties are kind of limited in that respect.

It would be interesting to see a flat motor with cleaner lubricating oil and longer wear & tear cycles than they usually have. Smoother operation and longer periods of time between maintenance would also be a good thing. It takes a lot of time and bucks to get there though.
 
Mike Davidson at Flatttack Racing uses a GM CPU for his fuel injection set up. Sells it with a researched basic Flathead advance curve. He will loan his Eprom burner out with a $500 deposit (fully refundable ) if adjustments are needed.
He may well be happy to sell you an Eprom already set up. The curve is set up to advance 1 degree for every 100 rpm with a 25 degree limit and a built in rev limiter.
http://www.flatattackracing.com/products.html
 
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