Timing control yes/no ??

[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.

[andrewb70]

EFI timing control is great because it will allow you to set the timing curve not only based on RMP, but also based on load (vacuum/MAP). Yes....do that.

Andrew

[TheJDMan]

MSD actually recommends that when you first install one of their Atomic EFI systems, that you do not enable the timing control initially. The reason being that it adds an additional layer of complexity should you need to troubleshoot a problem. Instead, they recommend that you run without timing control until such time you have the system up and running and all the bugs worked out. Then you can go in and and add in the timing control. Ultimately, you will benefit from timing control.

[68Formula]

If you look at a timing map for an EFI engine, you'll see it's much more complex than a mechanical-based setup. Having this level of authority and the knowledge of how to tune it, can have benefits in power and driveability. Plus the being able to compensate for changing temperature conditions.

[Jeremy]

I made the change in ignition components to allow my FITECH to control timing. It has done as the others have stated in allowing so much more control of the tune. How smoothly my car drives now is night and day difference. It has really taken the edge off the 041 cam in my Pontiac 455. Off idle response is much better, clutch engagement is smoother, engine load at cruise is lower according to the MAP readings. No downside that I have found yet.

[WallaceMFG]

I've done timing control on two Fitech units, I highly recommend doing it. Ease of tuning alone makes it worth it.

With the Fitech unit, it just uses the points input on the MSD box to trigger the ignition. Because of this, I was able to keep the 2 step limiter on the MSD box functional. Your Mallory box may be similar, but if the EFI does the timing control you probably don't need the retard function of the box. The EFI should take care of that.

[Zspoiler]

I have a Crane HI-6TR for my 1979 Z- 28 RS Camaro Pro- touring car. .With a Weiand 142 mini-supercharger. With an HEI distributor and 15 lbs plus of boost. I use it to adjust it to the type of fuel I use. From premiun to high test racing gas.

[GoodysGotaCuda]

I've installed a FiTech with timing and it seems to be working ok. The FiTech system in general is a bit clunky, software updates often brick ECUs, handhelds go out, the initial setup requires the handheld to be unplugged to avoid battery draw [which will eventually wear out the small connectors], etc.

That said, I'll probably try a Holley Sniper w/timing next time for my Dodge Warlock. The distributor at the back of the motor in a truck makes for cumbersome timing adjustments, hitting a button sounds much better.

[Larry R]

I have Holley HP EFI's on both of my cars. One is a TBI, the other has MPFI. To me not having timing control is giving up a big part of the total engine management. I knew little about EFI when I started these projects, but went ahead with timing control. The way I see it is if you do not implement timing control, tune it up, then when you add timing control you will have to tune it up again. Just do the tune once with timing control, it's not all that hard.

[a67]

When I did my first EFI retro-fit on an old school muscle car (in the mid '90s), it was first implemented with spark timing control only. Using stock GM EFI parts off of newer vehicles, I didn't have a fuel delivery system put together yet. And wanting to drive the car over that Summer, pulled the EFI and dropped the carb back on. It was 100% better then using a mechanical distributor. The following Winter the fuel delivery system was installed for EFI. Getting the fueling correct is easy, the real gains are in the control of the spark advance. EFI without spark control just isn't worth the effort. Bob.

[a67]

When I did my first EFI retro-fit on an old school muscle car (in the mid '90s), it was first implemented with spark timing control only. Using stock GM EFI parts off of newer vehicles, I didn't have a fuel delivery system put together yet. And wanting to drive the car over that Summer, pulled the EFI and dropped the carb back on. It was 100% better then using a mechanical distributor. The following Winter the fuel delivery system was installed for EFI. Getting the fueling correct is easy, the real gains are in the control of the spark advance. EFI without spark control just isn't worth the effort. Bob. P.S. lets see if the formatting works on this post. Seems that there is an issue with this site removing the white-space formatting and running everything together...

[Jeremy]

Since going to timing control, I've been able to tune for mileage as well.

Before, I was getting 9 MPG for city driving. Once I made the change it went up to 12 MPG. Some more tweaking of the tune and paying attention to my driving style, I was able to get 16 MPG on the last city loop (Mostly 35 and under with the occasional 55 speed limit, no steady state 70 mph highway)

[SSLance]

So, I use a MSD 6530 www.msdperformance.com/products/ignitions/street_and_strip/parts/6530 with my carb setup currently. This box also allows me to control timing as well, but will only retard the timing on a MSD Pro-Billet distributor, not advance timing.

So basically you lock the distributor out and mechanically set it at the highest advance you think you'll need and program in when and where it will retard the timing to be given certain parameters. It'll use both engine RPM and vacuum signal to retard the timing to your set parameter.

I'm curious if this is similar to how the throttle body fuel injection setups control timing and\or mechanical distributors? Or will the brains of the FI setup advance and retard a distributor based on programmed parameters? What distributors do you use with the FI setups that control timing as well?

I'm considering a swap to EFI and this is something I'd like to keep or incorporate because it really enhances street driving.

[68Formula]

So, I use a MSD 6530 www.msdperformance.com/products/ignitions/street_and_strip/parts/6530 with my carb setup currently. This box also allows me to control timing as well, but will only retard the timing on a MSD Pro-Billet distributor, not advance timing.

So basically you lock the distributor out and mechanically set it at the highest advance you think you'll need and program in when and where it will retard the timing to be given certain parameters. It'll use both engine RPM and vacuum signal to retard the timing to your set parameter.

I'm curious if this is similar to how the throttle body fuel injection setups control timing and\or mechanical distributors? Or will the brains of the FI setup advance and retard a distributor based on programmed parameters? What distributors do you use with the FI setups that control timing as well?

I'm considering a swap to EFI and this is something I'd like to keep or incorporate because it really enhances street driving.

Depends on the sophistication of the system. But in general, most EFI setups at least control timing based on throttle position, manifold pressure, coolant temperature, and air temperature (some may include a transmission input to smooth gear changes). This allows for compensation during cold start and warm up as well as varying ambient conditions and driving loads.

[a67]

I'm curious if this is similar to how the throttle body fuel injection setups control timing and\or mechanical distributors? Or will the brains of the FI setup advance and retard a distributor based on programmed parameters? What distributors do you use with the FI setups that control timing as well? I'm considering a swap to EFI and this is something I'd like to keep or incorporate because it really enhances street driving.

I used a stock GM computer controlled distributor, small cap. GM also used large cap computer controlled distributors. The base distributor timing is set with a light with a running engine and the EST/BYPASS connector open. Usually in the 6° to 10° degree range. This sets up the cranking timing.

Once the engine is over 400 RPM the ECM takes over timing. Newer GM systems can also control the cranking timing. The actual timing can be retarded some from the base setting, and advanced by more. Usually in the -3° through +42° from the base setting. This is a limitation of the distributor to prevent cross firing.

The actual timing that gets used is pulled from various tables. The main spark table is based on RPM and MAP (load). Then there are other tables that are based on items such as engine coolant temperature and load. Then intake air temperature, and the detonation detection system.

Bob.

[Interceptor5588]

I made the change in ignition components to allow my FITECH to control timing. It has done as the others have stated in allowing so much more control of the tune. How smoothly my car drives now is night and day difference. It has really taken the edge off the 041 cam in my Pontiac 455. Off idle response is much better, clutch engagement is smoother, engine load at cruise is lower according to the MAP readings. No downside that I have found yet.

What distributor did you use for the Pontiac V8? I've heard the 301 turbo distys can be made to work.

[SSLance]

I used a stock GM computer controlled distributor, small cap. GM also used large cap computer controlled distributors. The base distributor timing is set with a light with a running engine and the EST/BYPASS connector open. Usually in the 6° to 10° degree range. This sets ups the cranking timing. Once the engine is over 400 RPM the ECM takes over timing. Newer GM systems can also control the cranking timing. The actual timing can be retarded some from the base setting, and advanced by more. Usually in the -3° through +42° from the base setting. This is a limitation of the distributor to prevent cross firing. The actual timing that gets used is pulled from various tables. The main spark table is based on RPM and MAP (load). Then there are other tables that are based on items such as engine coolant temperature and load. Then intake air temperature, and the detonation detection system. Bob.

That is awesome... Thanks for the explanation, exactly what I was questioning.

Is there a list of EFI setups that do control timing like you described above, say on a small cap GM distributor?

[andrewb70]

That is awesome... Thanks for the explanation, exactly what I was questioning.

Is there a list of EFI setups that do control timing like you described above, say on a small cap GM distributor?

Lance,

I can't think of a single system that doesn't have timing control.

Andrew

[Jeremy]

I used MSD 8563 on my Pontiac. It plugged right into the FITECH. I also used the adjustable rotor from MSD. The worst part was buying a second cap to drill a hole in it so I could inspect the rotor phasing. $30-40 dollars just to mock everything up.

[SSLance]

Lance,

I can't think of a single system that doesn't have timing control.

Andrew

Do they all allow you to tune the timing control also? And do they work with or without a timing controlled distributor?

[andrewb70]

Do they all allow you to tune the timing control also? And do they work with or without a timing controlled distributor?

Yes, the point of having the EFI system controlling the timing is that you can program what timing you want based on RPM and load (vacuum). Here is a link to the Holley Sniper system instructions. Ignition is covered starting on page 25.

http://documents.holley.com/199r11031r.pdf

Andrew

[a67]

Do they all allow you to tune the timing control also? And do they work with or without a timing controlled distributor?

There are some systems that have a fixed non-user tune-able timing MAPs. Off hand I don't recall which ones they are.

Bob.

[a67]

What distributor did you use for the Pontiac V8? I've heard the 301 turbo distys can be made to work.

Push comes to shove, can use the bottom of the distributor that matches the block, and the top of a Chevy distributor. The bodies can be welded together. Need to take into account the inner shaft length.

I know a guy that did this for a 455 Olds engine.

Bob.

[andrewb70]

Push comes to shove, can use the bottom of the distributor that matches the block, and the top of a Chevy distributor. The bodies can be welded together. Need to take into account the inner shaft length.

I know a guy that did this for a 455 Olds engine.

Bob.

I am pretty sure that GM went to HEI ignition on all engines around 76-77, so there are HEI distributors available for Pontiac engines.

This should work with some minor modification as described in the Holley Sniper instructions.

https://www.rockauto.com/en/moreinfo.php?pk=3863754&cc=1250581&jsn=397

Andrew

[a67]

I am pretty sure that GM went to HEI ignition on all engines around 76-77, so there are HEI distributors available for Pontiac engines.

This should work with some minor modification as described in the Holley Sniper instructions.

https://www.rockauto.com/en/moreinfo.php?pk=3863754&cc=1250581&jsn=397

Andrew

That works for the Holley Sniper system, but that distributor is not a computer controlled unit. Many EFI systems require a computer controlled ignition control module (ICM).

Bob.

[andrewb70]

That works for the Holley Sniper system, but that distributor is not a computer controlled unit. Many EFI systems require a computer controlled ignition control module (ICM).

Bob.

I'd be curious to see what other EFI systems you're talking about.

Andrew

[a67]

There are many, any of the GM systems that drive a DIS or distributor. These include systems offered by Howell, Dynamic EFI, and Affordable Fuel Injection (AFI). The mega/micro Squirt systems, and the user tuneable FAST systems.

I am sure that there are others, just don't have the time to research it.

Bob.

{edit: did discover that the Haltech GM systems also require a computer controlled distributor.}

[andrewb70]

There are many, any of the GM systems that drive a DIS or distributor. These include systems offered by Howell, Dynamic EFI, and Affordable Fuel Injection (AFI). The mega/micro Squirt systems, and the user tuneable FAST systems.

I am sure that there are others, just don't have the time to research it.

Bob.

I looked these up briefly. None of them offer a built in wideband O2 sensor. Why would anyone buy these?

Andrew

[a67]

I looked these up briefly. None of them offer a built in wideband O2 sensor. Why would anyone buy these?

Andrew

Cost?

The FAST systems do. Besides, getting the fueling in line is easy. And if the system is always learning from the WB, what happens when the controller or sensor goes bad?

I could ask the same question about fuel only EFI systems. Why buy one when spark timing is more important?

The difficult part is getting the spark timing correct. Not only at WOT, but for street driven vehicles it is important for drive-ability.

Bob.

[andrewb70]

The Holley Sniper is under $1000. Once the fuel tuning is done, it is advisable to limit the O2 compensation to a small amount in case if sensor failure.

Timing is not automatically adjusted, but it's not rocket surgery to get it right in most hot rod applications.

Andrew

[a67]

You need to broaden your view on why folks buy other systems. Such as, will the Sniper work on a TPI system? Others require a system that supports emission controls. I know I do which completely eliminates the Sniper as a viable system.

Bob.

[andrewb70]

The Sniper is an "all in one package." It is meant as a carburetor replacement system, and includes all the hardware, ecu, 3.5" touch screen, and wideband. Tuning can be done with the touch screen or with free software that runs on a laptop. Tuning can also be done "live." Personally, I am not a fan of any throttle body system, but it is better than a carburetor, assuming there is a way to tune it.

To each their own. I understand that people have different ideas of what they want and need.

Andrew

[railroad bob]

My project uses a 4.6L DOHC modular motor. This engine does not use a distributor, rather it has crank and cam sensors for timing, and individual coils for each cylinder.
Does anyone have experience using EFI with a similar motor?

I have been considering a FiTech sytem, but their tech says I would need to use a coil pack driver.
The EFI would gather a tach signal and run fuel only.

Are all the after market EFI systems configured similarly?

I don't really want to pay for feature I can't use.
Is there a system that runs fuel only, and that I can use with a turbo also.

Thanks...

[andrewb70]

My project uses a 4.6L DOHC modular motor. This engine does not use a distributor, rather it has crank and cam sensors for timing, and individual coils for each cylinder.
Does anyone have experience using EFI with a similar motor?

I have been considering a FiTech sytem, but their tech says I would need to use a coil pack driver.
The EFI would gather a tach signal and run fuel only.

Are all the after market EFI systems configured similarly?

I don't really want to pay for feature I can't use.
Is there a system that runs fuel only, and that I can use with a turbo also.

Thanks...

You will definitely want timing control with a turbo!!!

The Holley HP will do what you want it to do and way more.

Andrew

[railroad bob]

Thanks Andrew, I'll research that system...