EFI Q

For you guys that are running after market EFI with timing control, which distributor are you using?

Do you feel that you need the timing control (for the street-I won't run any type of boost)? I really like the Edelbrock E-Street kit however, it doesn't have timing control.

I live near the mountains at 5,000 feet and want to drive in the mountains where there will be over a 6,000 foot altitude gain.

It would be going in a 400hp (at crank) 440 b-body.

Thanks

I used a locked out lean burn unit when I put in my Megasquirt. With most of them you don't necessarily need to let the computer control timing. It is very handy to be able to dial in the timing to 1/10 of a degree, but I've found the base timing map is generally sufficient for me. As always, there are a few tweaks that can be made. Timing won't really affect driving over the pass here. Unless you are spending a significant amount of time at 11,000ft, it's generally up and over then back to a more regular altitude. I haven't noticed a significant change in vehicle behavior on the wideband o2 when I've been back and forth. Pretty much set it and forget it.

I wouldn't sweat it. The mixture control is at least 10 times more important than timing control for driveability with altitude shifts.

I regularly travel from my home base 3700 ft, over Wolf Creek Pass, to Lakewood, 5900 ft. Getting the A/F right is the most important thing. Getting my carb jetted to run at altitude has made a huge difference.

If you were doing dyno runs at the different elevations, you may want to check the effects of timing. But in driving, as in just driving from one place to another, I wouldn't worry about it at all.

R.

I too used a lean burn unit, by far the cheapest option if you're dealing with a system that will read an inductive pickup. I did rephase the rotor since the engine is set timed to 60* btdc to allow the computer to bring in any amount of advance up to that.

Have not decided if I am going with a Lean Burn or with a blocked off stock distributor. Megasquirt does a great job at timing. If Edelbrock does not do timing, maybe use a Megasquirt to do that and the Edelbrock do the rest.
Craig

My point is set your timing for wherever you do the most driving. You can use a regular distributor to good effect if you get the curve dialed in for where you do the most driving.

Electronic ignition advance control is a nice-to-have. BUT, having the right Air/Fuel mixture for whatever air conditions you are driving in at the moment is MUCH MORE IMPORTANT.

As I said earlier, if you were running dyno tests at different elevations, then you'd worry about ignition timing much more because you'd be trying to optimize at that particular condition.

But, as you are only driving a car on a road, the altitude's effect on timing has much less to do with the engine's performance than getting the A/F right.

And, if you are going to build a Megasquirt to only run timing, that's a wasted effort.

What do you think the electronic ignition timing control does anyway? It allows you to more easily dial in your curve. I'd be very very surprised if it changed that curve in response to air density.

Just buy the doggone EFI system you like the best and run it.

R.

This is the set-up I'm ordering; http://www.summitracing.com/parts/msd-2900

I already have a MSD Pro-Billet Distributor and 6A ignition box.

It is the complete system from one company.

Thanks Guys,

Was hoping you guys would chime in.

I was thinking about the atomic but I really like the Edelbrock's sump fuel system and their large tablet.

Best thing about editing controlled timing is how easy it is to dictate what you want your curve to be. Also you can run a lot more timing at idle than during cranking which can help depending on your cam. Don't forget the built in rev limiter too.

I bought the msd kit because of the timing control and price. Also bought the msd ignition box. Can I use my Mopar electronic distibutor? All I need is msd 84211 to use it w/timing?