[67 455 Bird ragtop]

I'm hoping to finally get my car running later this summer. As usual with projects things cause delays. Now technology has changed. I'm going efi. So I'm curious if I should run timing control or not. I currently have a new in the box Mallory vacuum comp 9000 8658001 distributor and a mallory 685 box. I liked the 685 box since it had starter retard.

But Now I'm debating to a timing control setup with MSD. Car will primarily be a cruiser with some track time. So am curious if I should switch to the MSD setup.

[chiphead]

I use the 685 with a RTR distributor, carb and nitrous plate, I really like it for the window switches and retard functions.

I thought most of the EFI controllers also controlled spark advance? Depending on the EFI you go with, ign and fuel delivery are done by the same controller. What EFI are you going with?

[JLMounce]

Timing control can be beneficial in a number of ways depending on your circumstances. If you want to go that route, don't just go and buy a setup first. instead look to see what is compatible with the EFI system you are choosing, then make the choice on equipment that best suits your needs and works with that system.

With that said, if you just have a street car and you're not looking for every 10th and you don't need to control nitrous or retard spark advance for boost, you may not see much real benefit to going spark control. A quality and well setup standard type distributor will be more than adequate for such a car.

[67 455 Bird ragtop]

Originally Posted by chiphead

I use the 685 with a RTR distributor, carb and nitrous plate, I really like it for the window switches and retard functions.

I thought most of the EFI controllers also controlled spark advance? Depending on the EFI you go with, ign and fuel delivery are done by the same controller. What EFI are you going with?

I was thinking of going this way if I did go with timing control. Because I do like the features of the 685 box. Just not sure if it's that big of a deal for primarily a street car. But at least I have your experience with that combo. And I assume the RTR yourun is the mechanical advance version not the vacuum one.

I appreciate the feedback.

[67 455 Bird ragtop]

Originally Posted by JLMounce

Timing control can be beneficial in a number of ways depending on your circumstances. If you want to go that route, don't just go and buy a setup first. instead look to see what is compatible with the EFI system you are choosing, then make the choice on equipment that best suits your needs and works with that system.

With that said, if you just have a street car and you're not looking for every 10th and you don't need to control nitrous or retard spark advance for boost, you may not see much real benefit to going spark control. A quality and well setup standard type distributor will be more than adequate for such a car.

Thanks for the feedback. Your last sentence has been my quandary ...

[Firebob]

True, but if you have the advantage of timing control option why would you not? I don't believe there is a downside to using it. In my case it didn't seem to make much difference to the way the car runs. Everybody said it'll smooth everything out and it won't sound like there's a cam anymore but mine sounds prett much the same.

[chiphead]

To be clear, I was using the mechanical and vacuum adv on my rtr dist. The 685 pulled a fixed amount of timing only when nitrous was activated. Smart efi can pull on the fly depending on the system. And it's programmable, no choosing weights and springs. Likely overkill for you, but a "nice to have" if u can afford it.

[dmac]

Originally Posted by Firebob

True, but if you have the advantage of timing control option why would you not? I don't believe there is a downside to using it.
.

For a street car, isn't this just one more thing that can go wrong, or are these systems super reliable?

[Squidward]

I did FiTech with timing control on my Lemans because I wanted to bridge the gap between new and old, and play with the full range of timing control by custom tweaking the curve. Never again worry if my weights are rusty, springs are worn, or vac diaphragm leaks. It either works flawlessly, or it doesn't.

I did FiTech without timing control on my Firebird, because having 2 cars stresses the budget, and having the timing control would have been another $500 (+200 for FiTech that does timing, +300 for 2 wire distributor stuff). Besides, the distributor on my FB works great. That was a much needed 500 I could spend elsewhere.

[Lee]

Going EFI without adding timing control is silly, IMHO.

I've installed 3 FAST systems now, all with the FAST Dual-Sync distributor. It plugs directly into the EFI wiring harness. As such, it is operating as a cam position sensor, as well as a distributor. EFI can only be as accurate as the RPM signal it is basing all the fuel calculations upon. When a tach signal off of the distributor or ignition box is used for the RPM signal, the ECU is only getting one signal for every two rotations of the crankshaft, where a Dual-Sync is giving several signals each rotation - allowing for more precise calculations, and better performance.

With the ECU controlling both fuel AND timing, it can utilize both to smooth idle and also to smooth abrupt changes in load or throttle position. The engine will respond more quickly to the timing changes than the fuel changes, so it makes for a much smoother running engine than when having a fuel-only system.

So, I would NOT waste money on the MSD stuff. But I WOULD get a system that most easily integrates into the EFI system you choose, once you go EFI.

[Firebob]

Makes sense Lee but that extra $500 is a tough pill to swallow when you know you can make it work without spending the extra dough. Maybe not perfect, but pretty good.

Dmac, most everything is pretty reliable till it isn't.

[67 455 Bird ragtop]

Originally Posted by chiphead

I use the 685 with a RTR distributor, carb and nitrous plate, I really like it for the window switches and retard functions.

I thought most of the EFI controllers also controlled spark advance? Depending on the EFI you go with, ign and fuel delivery are done by the same controller. What EFI are you going with?

I'll probably go with that does timing control.

[Lee]

Originally Posted by Firebob

Makes sense Lee but that extra $500 is a tough pill to swallow when you know you can make it work without spending the extra dough. Maybe not perfect, but pretty good.

Dmac, most everything is pretty reliable till it isn't.

If "pretty good" is the goal, then save even more money and stick with a carburetor!

I worked on a Sniper system for a local guy a few weeks ago. No ignition control. It runs "pretty good" but nowhere near as smooth as it could be if it were controlling the ignition.

The control over the timing with an ECU ranges from great to amazing, depending upon the system. Some systems will give you up to 256 "cells" (based upon RPM and engine load) that you can enter different timing values. Admittedly, some of those cells are in conditions that you'll rarely or never encounter (like 100% load at idle). But if you take the time, you can dial in your timing to an incredible degree of precision.

[Firebob]

Ah, but you need to know what you're doing. I had my curve with my original dist set where I wanted it and when I changed over to TC I entered the same parameters that I had so I guess it's not unexpected to figure that it should run much the same. If I pulled up the timing map in the software I wouldn't know what to change or why. Great to have good tools. Even better to know how to use them.