EFI Conversion Using Stock Delorean Intake Manifold

[DeloreanJoshQ]

Shannon is not running coil packs. To do so he would need to add both a crank and cam trigger as well as the coil packs or COPS.

His list also omitted a fuel pressure gauge.

how difficult is it to add cam and crank sensor? Otherwise, the distributor runs independent with no options to control the timing via megasquirt?

[Spittybug]

DeloreanJoshQ, have you done any reading on the Megasquirt systems yet to get a feel for their capabilities?

The cam and crank sensors are BOTH required for our odd fire engines so that MS can correctly index to TDC of #1 on the compression stroke to get the timing correct. This isn't necessary with a distributor since it is the physical configuration of the 90* and 150* layout of the plug wires in the cap that does this automatically. To add the sensors one must physically attach a 36-1 tooth gear on the crank pulley and a 1 tooth gear to either the end of a cam shaft or in place of the distributor.

Megasquirt is fully capable of adjusting timing without all of the above; but you do need to disable the mechanical advance in the base of the distributor. You also remove the vacuum advance. MS allows you to plug in an advance degree for each cell of your MAP x RPM table. This way you can mimic the stock behavior if you like or improve upon it. Especially helpful to be able to digitally control the advance under boost conditions when you need to retard timing to prevent pre-detonation due to a more compressed charge. That is harder to do with a stock setup. It is easy to really fu$k up your engine if you don't understand the principles behind engine timing. Conversely, this is probably the most important variable for optimizing power.

The only benefit of the triggers is to be able to run COP or packs, eliminating the physical distributor and singular coil. You have to add 5 more coil driver circuits to the MS unit (~$10 apiece).

Lot's of good information in the EFI section and in the MS manuals: http://www.megamanual.com/index.html

[lazabby]

An update on my car. I've been fighting a 300-400 difference in RPM between Park (no load) and Drive (under load). No tweaking of the programs seems to narrow that difference. I tried switching to closed loop but couldn't get closed loop to work. I posted a query on the Megasquirt forum and the consensus there is that closed loop will not work unless one has a throttle position sensor. My car doesn't have one. Another alternative suggested is to install and EGR vacuum solenoid that allows more air in when in drive but closes when in park.

Other than that the car is actually driving well. I need to do some tweaking at righer RPMs to get better performance, etc.

When we started this project, conventional wisdon was that the manifold would have to be replaced on the stock Delorean engine. Owen figured out how to retain the stock manifold.

It would appear that it would be ideal to retain the stock idle air valve and conroller as the Delorean IAC seems to do well.

[Spittybug]

I'm still not convinced the issue isn't specific to Shannon's car. From what I gather from others, a 300-400 RPM drop is excessive compared to other Delorean automatics.
Ian's manual conversion is running pretty nicely I think. The IAC code does have some issues, but I've been meaning to check out the new code which claims to have addressed some of them.

[dmc6960]

Couple of notes here...

An update on my car. I've been fighting a 300-400 difference in RPM between Park (no load) and Drive (under load). No tweaking of the programs seems to narrow that difference. I tried switching to closed loop but couldn't get closed loop to work. I posted a query on the Megasquirt forum and the consensus there is that closed loop will not work unless one has a throttle position sensor. My car doesn't have one.

Yes, you really should have a TPS. Even if your using pure MAP for acceleration enrichment, as you've now found another reason. Get one, install it.

It would appear that it would be ideal to retain the stock idle air valve and conroller as the Delorean IAC seems to do well.

This is something I've been saying from the beginning. Its a really well done system and works well in just about any setup.

When we started this project, conventional wisdon was that the manifold would have to be replaced on the stock Delorean engine. Owen figured out how to retain the stock manifold.

I'd hardly call it conventional wisdom. I dont have any hard numbers, but before my EFI conversion in 2010, all existing EFI conversions I saw were using the stock manifold and TBs (Eagle engine swaps and turbo conversions notwithstanding). It was just coincidence that the next three publicly documented conversions all used alternate intake manifolds (mine-Z7U, Owen-Carb, Mike-Z7U).

If Owen had his "kit" ready when I did mine, I may have gone that route, but keeping the stock idle control of course . The biggest thing I didn't want to worry about was the fuel rails. The Z7U afforded me that option at the expense of a few other complications. I was happy with the trade-off.