Is it difficult to find a Coyote from a totaled unit, and what do they run?

Sounds like the first thing you need to do is find out exactly how many ponies you are riding. Hook it up to a dyno and measure it. Find out where you are, then you will be able to determine where you are going. THe operator will likely have some ideas on how to improve it, also. With electronic ingnition, may be a simple as a different chip.

You may also want to consider the power range that you will be typically running in. A power band that is targeted towards a power band in the 4,500-7,000 rpm range can provide impressive numbers, but unless you plan on driving in 1st and 2nd in town and 3rd on the highway only, it is not very practical for the street if your complaint is not enough power driving between 45-70 mph.

Look for an engine or changes that will put the power where you need it.

Comparing the days when the Super Snake was created to now are two different eras IMHO. There seems to be far more powered kits in the realm of the Super Snake nowadays than the total of them made.

I am pretty sure adding the C4 really screwed the F/R distribution. E.g. Moving weight to the front to an already biased one because of the dual Paxtons. Talk about a light rear. Tire technology was abysmal back then.

I had an FFR with a 302 much like yours. BUT, I had 3.73 rear gears. Made my engine come alive. If you don’t want a power adder such as a turbo or supercharger, lower gears are your least expensive option.
Luckily, you’ve got FI so you don’t have to make jet adjustments for high or low altitudes.
If you do decide to swap out the engine, and keep the 3.31 rear gears, look for a torquer engine, not a revver. Lots of torque right off idle. The reason is that your rear end will work against you at that altitude and you’ll never get to use that overdrive 5th if you have a high strung engine.
I currently have a 560 lb/ft engine and a 3.46 rear end. Would love a 3.31 as it would make first gear much more useable.

Torqstorm systems run about $3K, but you'd also need to replace your EZ Fast EFI with a system set up for blow-through boost. Mustang360° put a Torqstorm system on a built 5.0L EFI engine and got a 50%+ increase in HP with 10 PSI of boost:

• Before: 407 horsepower at 6,200 rpm and 397 lb-ft of torque at 4,500 rpm
• After: 638 horsepower at 6,400 rpm and 545 lb-ft of torque at 5,600 rpm

That's increases of 231 HP (57%) and 148 lb-ft of torque (37%).

Your cam has left lift and duration, so you're unlikely to get to those levels but, as noted in the article, that's block-splitting territory - so keeping power levels down a bit is not a bad idea. Limiting it to lower boost levels would probably be a good idea for purposes of longevity.

TorqStorm Fuelie 5.0L Test

TorqStorm Small Block Ford Supercharger Kits

The flatter the torque curve (the closer the torque is to a flat line) over say 2500 to 5500 rpm, the more predictable and therefore the easier the car is to handle. If all you're interested in is drag racing (idle or full throttle), this isn't important. If you are driving around twisty roads and are not a trained race driver, then the flat torque is very important. Possibly life saving important.

That said stay away from centrifugal blowers. They make almost no pressure at low rpm.

I think if I was in your shoes, I would sell the engine if you can get anywhere near what you said. Those heads make more power than the stock factory heads, but not much more. The E303 cam sounds good and that is about all it does. The only thing I would use out of that engine is the Block, and lifters.

Go 347 stroker. Spring for a boss block or aftermarket if you can afford it. Better oiling and stronger. For a couple hundred more you can go to a 4.125" bore and get some more CID and un-shroud the valves. Put good heads on it. The heads make the engine. Don't screw up a perfectly good engine with a junk intake. Match the cam up to everything else.

Talk with Brent Lykins or Craft Racing, whichever you are closer to.

My old car had 350ish rwhp, the SPF came with a dyno chart showing 472 at the rear (roush 427r).

On 10 year old rubber, it's unusable at anything over 1/2 throttle in the first 3 gears. I'm looking forward to stickier rubber on this one!

With these light cars I think a centrifugal blower like a Paxton will feel better. A positive displacement blower works great on heavier vehicles like my truck, but it doesn't take much to break the wheels loose on these light cars.

That said if you're going to get around 350 ish ft/lbs torque at the rear wheels, that's probably just right.

-Dave

Listen to this guy ^

There is only one way to make power, and that is to combine more cylinder pressure (not compression ratio, don't get these terms confused), with more/better exhaust scavenging, and to multiply these factors by adding either cubic inch displacement, adding raw oxygen (nitrous) or positive displacement (forced induction).


If your 302 is strong in all 8 holes, and doesn't make any blowby or leakdown, then at 5000 foot elevation, the best way to add cylinder pressure (without replacing the engine) is going to be with either turbocharging, supercharging, or nitrous. A direct drive centrifigal blower is the best mechanical method (meaning most efficient for the $) for acheiveing this goal on a small cubic inch engine, IMHO

I also like jhv48's point about the gears- lower rear gear can mean faster RPM ramp rate- very beneficial at higher altitudes.

This is an accurate point when applied to the older style belt-driven hair dryers (which "feel" a lot like turbos as they spool up); but the latest crank drive blowers out there now are able to start adding boost as low as 1500RPM...

Excellent. Thanks for the responses. Think Paxton SC.
But the real answer is No Easy way, as in not an inexpensive tune or bolt on. I need to make sure this is a darn good keeper before I put this kind of $ into it.

Dump that E cam. those are designed for heavier cars and IMO suck for performance. Might try a custom cam from Bullet.

Also, rear end gearing has been mentioned. You'll get that seat of the pants feel of acceleration but lose some top end speed. With a small block motor, doesn't make much difference as they can wind pretty high RPM's.

The on-line junkyard database Car-Part.com--Used Auto Parts Market
5.0
Approx $3.5k - up for just the engine, $5-7k for the Engine/ECU&harness/ 6sp manual.
5.2 from a GT350 $10-17K

3.55? 3.73?
How do you go about choosing a new cam, how expensive to replace (sounds labor intensive) and as long as we're going to be in there, what else to do?

3.55? 3.73?
Personal choice dependent upon tire size and trans gearing (.82 vs .64 OD), where cruising RPM should be tolerable to you.
You should be able to find a speed calculator online. Typically, you will need to know revolutions per mile for the tires.

They can angle the blades and make improvements, but a true centrifugal blower, the pressure output is proportional to the tip speed of the blades. The relationship is typically pretty close to: pressure equals tip speed squared. Since it is difficult to fit a 3 foot diameter blower in a car, they end up with a small diameter and a planetary gear set spinning the wheel up to 80,000 rpm to make pressure. At low rpm the boost is very low, with little increase in boost for a 1000 rpm motor increase. At high rpm, boost is high, and a large increase in boost for a 1000 rpm motor increase. Torque is proportional to boost, and boost increases with the rpm squared. This gives a very steep increase in torque over the rpm range, until the engine pumping efficiency starts dropping off rapidly. Once that point is reached, the centrifugal blower and engine combine to flatten the torque out for a while.

Multi stage compressors wheels exist in industry, but I have never seen them in an auto application. The pressure is still proportional to rpm, but not as steep. These need a good deal of application design and cannot handle a lot of variable changes, as they can get into vibration harmonics and destroy themselves. I don't see these going into auto applications, but I get surprised all the time. I just doubt that there is any centrifugal blower that doesn't have a steep rpm to pressure curve. Physics doesn't change much.

Now change to the roots bower, or better, a screw compressor and they are positive displacement blowers. You pretty much get the same boost pressure (thus torque) at all rpms.

So let's assume your engine NA has 300 ft-lb torque from 2500 - 4500 rpm and then it starts dropping off to say 250 ft-lb at 6000 rpm. With a centrifugal blower you may get 350 ft-lb at 2500 rpm at 2.5 psi boost. At 4500 rpm you are likely at 8.4 psi and 470 ft-lb. At 6000 rpm you are likely at 15 psi and 500 ft-lb. Some of that torque would be consumed by the blower belt, but that's more work than I wanted to put into this, so I am ignoring those losses.

In comparison if you used a positive displacement compressor at 15 psi boost (again ignore power robbed to drive the blower) you would double the torque everywhere. So cruising down the road and pulling up a mountain at 2500 rpm the positive displacement would would have about 600 ft-lb of torque available, where the centrifugal would only have 350 ft-lb available (only 50 more than the engine had normally aspirated). Sure drop two gears and rev it up to 6000 rpm, they both have the same torque, but every place below that, the positive displacement wins hands down.

I hate a different torque at every rpm. So you come out of the first turn at 2500 rpm smash it to the floor and get a modest 350 ft-lb of torque. Yea this is fun. The next corner you are at 4500 rpm and smash the throttle, expecting the same fun, only the engine pumps out 470 ft-lb of torque. The tires break loose on a corner, in a 90 inch wheel base car, and you are dead.

With the centrifugal smash it in first gear, and your tires will hold to the ground until the rpms come up. If you do not back off the throttle before the tires break loose they will rapidly go up in smoke. To keep the tires from breaking loose, you have to continually back off the throttle, as the rpms increase to keep the tires hooked. Same thing in every gear. Not for me.

First I will admit I am no expert, but I am considering a larger carb witch I was told will run leaner . I think that will help with altitude . I was told carbs run higher hp than fuel injection.

A larger carb will only give you less throttle response etc.

You need to run less mainjet area across the whole carb to compensate for altitude. The air density goes down, so you pack less air volume, which is less oxygen, so we need less fuel to match.

All else being equal, a GOOD carb can match or exceed EFI for power, but a good EFI will win hands down in every other way. Cold start drivability is the first win area for EFI.

Gary

Cars are like women, the longer you have them, the less "exhilarating" they become.
That said, I'd start with the aforementioned rear gear reduction, that would probably
be the cheapest route. Adding a power adder and especially changing cams could lead
to valvetrain issues, make sure your engine build is "stout" enough to handle whatever
you want to add.