Altitude: reason for a Coyote?

[FastTom]

Hi All

Newbie here...from the Denver area...nearing a purchase of a Backdraft.

I wonder if any of you Colorado folks, who perhaps live along the front range at an altitude of 5,000'+, and often drive up into the mountains, maybe up to 10,000' or more, have any trouble with your carbureted 427s? Is this a non-event, or perhaps a slight nudge toward choosing EFI and a Coyote engine?

(I realize this forum isn't very active...anybody out there?)

Thoughts appreciated

Tom

[twobjshelbys]

Originally Posted by FastTom

Hi All

Newbie here...from the Denver area...nearing a purchase of a Backdraft.

I wonder if any of you Colorado folks, who perhaps live along the front range at an altitude of 5,000'+, and often drive up into the mountains, maybe up to 10,000' or more, have any trouble with your carbureted 427s? Is this a non-event, or perhaps a slight nudge toward choosing EFI and a Coyote engine?

(I realize this forum isn't very active...anybody out there?)

Thoughts appreciated

Tom

If you don't go through wild altitude changes a carb'd engine can be set up to operate fine. No matter what you'll lose 15-20%.

If you go from Denver to sea level it will run fine. If you go from Denver and track it at Riverside you'll need to re-jet. Similarly, driving from Denver up Trail Ridge you'll operate fine. If you could find a 14000' track you'd want to make adjustments. Cars have been doing this since, well, forever. Having good tuning at 5000 is ideal. When I was a kid we lived in Iowa, and my dad would have our Suburban re-jetted for Rocky Mountain Park trips since we spent alot of time in campgrounds above 8000'. We noticed the difference when going from low altitude to high altitude for longer operation especially towing.

If you do go from sea level to the top of trail ridge often, then a good fuel injection system can be used on the classic engines. For added visual appearance several manufacturers make a fuel injected "8-stack" that looks like webers. Pretty cool. My small block 427 had the 8-stack fuel injection. Roush didn't get the programming right because they failed to fill in the altitude compensation table but once I did it was fine. New systems do all this automatically.

Everything I said applies equally to a 65 Mustang as a Cobra...

Cobras with period correct engine are lots easier to sell than ones without.

[eschaider]

Tony's points are all spot on. If you want period correct and easier resale stay with traditional Cobra engines. If you are after something special, like the ability to accommodate eclectic altitude changes then EFI is you answer and you can put it on a traditional Cobra engine in particular with a Weber style appearance that is simply to die for — plus all the niceties of EFI.

If you are building for yourself then all rules except one are out the window. The only rule that counts is build it to your personal taste. There are not many potential buyers that would approve (i.e. pay a premium) for my car because of the engine I chose. For me it was perfect, for most others — not so much.


Ed

[bobcowan]

I live in Colorado Springs, 6,200' ASL. I frequently travel through the mountains, with altitudes as high as 12,000' - Independence Pass, Trail Ridge Road, etc. We do a lot of drives like this as a group; some EFI and some carbs.

The EFI does MUCH better job at handling these altitude changes than a carb does. I hate being behind a carbed car on these trips, because the exhaust stinks and gives me a headache. The carbed cars also have some difficulty starting at high altitudes - very easy to flood them.

I have owned both carbed and EFI engines. IMO, EFI is the way to go if you plan on enjoying what Colorado has to offer. A reasonably well tuned EFI will handle all the changes in air density and temperature you might come across around here. Just turn the key and drive.

You don't have to have a Coyote or LS for EFI. There are plenty of good aftermarket EFI systems on the market that can easily be applied to an FE, Lima, or SBF. Some look like a carb. And some look pretty trick.

Gary can get you hooked up with local sources for installation and tuning.

[bobcowan]

This is the FFR I drove here for over a decade. It was awesome! I probably shouldn't admit this, be a couple of club members and I ran up Berthoud Pass well in to triple digits. I also won multiple regional championships in this car.





This is the BDR I have now. It has a Coyote because I just wanted one.

[FastTom]

Thank you all for the wisdom! I love the story about re-jetting the Suburban for CO road trips!

I had not really considered a 427 with EFI; I was of the mindset that EFI led to Coyote, in part because nowadays I do have a bias towards more driving and less wrenching.

It sounds like there is a lot of advocacy for a 427 with EFI. In this case, can I still have the great sound of the carb'd 427? Are these reliable setups, that don't take frequent tinkering? Are there any preferred EFI setups?

[RunWithScizzors]

Except that when a carb'd engine runs too rich or too lean, its 'tone of voice' changes a little, whereas a well set up EFI is always on point, I don't think there's a different sound.
Modern aftermarket EFI systems seem mature. Once correctly set up, they don't have a reputation for needing any onging tinkering.
Here are some leads:
Pro-M Racing Mass Air Sequential Port EFI System https://www.promracing.com/complete-...i-systems.html (expensive, maybe the best: mass airflow and sequential port injection, same source as Ford OEM)
FAST EZ-EFI Multi Port EFI Kit https://www.fuelairspark.com/ez-efir...ttle-body.html
Holley https://www.holley.com/products/fuel...on/legacy_efi/
Edelbrock https://www.edelbrock.com/shop/fuel-..._list_dir=desc
FiTech https://fitechefi.com/product-catego...ort-injection/
There are more out there, but there's a start. I'm sure some of the guys here running EFI will chime in on their experiences.

[eschaider]

Originally Posted by FastTom

...

It sounds like there is a lot of advocacy for a 427 with EFI. In this case, can I still have the great sound of the carb'd 427? Are these reliable setups, that don't take frequent tinkering? Are there any preferred EFI setups?

The sound of the engine is determined by cam selection, cam phasing and to a lesser extent c/r. EFI just makes sure the engine is always fueled correctly.

There is a MegaSquirt offering that has a considerable number of good attributes. At first you will discount it because it sounds like it is for the wrong engine. It is called MS3Pro PnP and it is offered for a range of Modmotors but works on any internal combustion engine.

The beauty of the MS3Pro PnP system is both its price $1,349 and the fact it uses an OEM engine harness you can get out of a salvage yard. The conversion to a non Modmotor platform will require an update to the engine displacement, fuel injector sizing for your engine, possibly a firing order change depending on the engine you select and potentially lengthening or shortening selected sensor wires in the OEM harness. All are very easy to do.

Because it uses all OEM Ford sensors you do not get ambushed by repackaged GM OEM sensors at elevated pricies. Here is a clickable link to the unit => MS3Pro PnP There are a lot of things to like about the system but one you will not find anywhere else is a Lifetime Warranty — yeah I know, never heard of that on an aftermarket EFI system before either.

Almost forgot it supports virtually any ignition coil you want to use including the double throw down Mercury Marine IGN-1 and IGN-1A coils. You will need a cam position sensor to tell it where #1 is but those are available from Summit in distributor replacement packages.


Ed

[Cashburn]

A properly setup EFI system on a 427 should check all your boxes.