Data on % of FTP for racing with power?

Very roughly.

Sprint 95-100%, Oly 90-95% HIM 80-85%, IM 70-75% (I think, I never did one)

Also depends on duration of the bike portion. For hilly courses you can use Normalized power. For example, your NP should be 80-85% of FTP for a HIM.

These should be based off an accurate FTP, so the more you used "estimates" to get your FTP, the more they will be off

There are some more detailed threads specific to each distance.

NP of 95-100% for sprint, 90-95% for Oly, 80-85% for HIM is pretty solid and common advice.  68-72% for an IM is probably the more common guidance for an IM.  75% starts getting into more elite level territory.

The estimates Marc listed are pretty good guidelines.  But you should probably factor in expected finish time for the bike leg as well. 

For example, if an athlete can finish the bike leg of most HIMs in 2:45, then it's likely the athlete will shoot for 80-85% of FTP for most HIM bike legs.  But a course like Savageman...because of it's difficulty...that same athlete may take 3:00 to 3:10 to finish that same bike leg.  So he likely will need to adjust his power goals to something like 78-83% of FTP to account for the extra 15-25 minutes he will be on the course.  At the same time, if the athlete chooses an extremely fast bike course he can expect to do in 2:30, he can also shoot for a slightly higher power goal. 

The key also is that you need to train yourself to be able to ride at a given power level and still be able to run.  I'd wager that most triathletes don't put in nearly enough training to ride at 80-85% for a HIM and still run well.  Experiment in training with a 45-50 mile bike ride at race power and then follow it up with a 4-5 mile run at race pace to see how it feels. 

ETA: Again, the person trying to finish in 4:45-5:15 for a HIM can probably ride closer to 80-85% because they are spending less time on the course.  And as mentioned above, 75% for a IM is closer to elite.  They can go harder because they are only racing for 9.5-11 hours.  If you plan to race for 12-15 hours...you need to back off.  My guess is that IM pros who are riding 4:30 IM bike splits are probably closer to 80% because of superior fitness...and they are riding over an hour less than most AGers.

In his Quarq interview, Jordan Rapp shared his power data and won IMTX at 80% of FTP.

I was kind of brief in my first post when I said "duration" was a factor. Gman and Jason expanded on it.

Here is a chart that Friel used in one of his articles (here)

Sure enough the 6:30 guy should go at 67% and the pro 80%, so I think you are finding consensus

You can do the same math for HIM to base pacing off TSS. A 2.5hr at 85% of FTP is similar to 3hr at 80% in terms of TSS, the 2nd being slightly higher

I suggest to ride at the conservative end of those ranges and build up from race to race. An accurate FTP is very important.

I would bet 98% of people overestimate their true FTP.

80% of an overestimated FTP will lead to a bad run in a HIM.

I've been using a power meter for 3 years now in training and shorter races.  Unfortunately I can't use my PT during the HIM I do because I can't use a disc cover so I opt for a 404 (not PT) set.

So most of my races with power are only 20-60 minutes in length.  Sprints, short TTs, 40k TTs, etc.  And with that, I completely agree with Fred that you should really avoid using a very specific % of FTP as your power goal for long course racing.  It can be a general "guideline", but really this is something you need to test during training.  The fact that most people estimate their FTP based off a 20' test makes their FTP value an "estimate" at best.  Even for shorter course racing and TTs, my 20' power tests have a hard time matching up exactly to what I can put out for 1 hour.  It's usually in the "ballpark", but it's not uncommon for it to be off by 2-3%.  I can only imagine how much variation you can get from trying to target your IM power goal off a 20' test rather than targeting your IM power off a 4-5 hour training ride.

A couple of suggestions for knowing if your FTP is ok for determining HIM pace...

Do 2x20 at 100% of FTP. If you can't do it, your FTP iis too high

Do an Oly at at least 90% of FTP. If you can't do it or can't run, your FTP is too high

Do a race rehearsal, 3hrs at 80% + a 30' brick. If you can't run properly, you are too high.

Those were my three tests to confirm my target pace and then I adjusted on race day.

It's not an easy ride, but the one that will tell you how to pace your HIM. Probably one of the most critical workouts building to a HIM.

HIM at 80% is a tough ride.  It's an estimate.  I hear this number thrown out here all the time, but in reality you need to be really well trained to pull it off.  You're not going to go through a basic HIM plan or any plan to complete an HIM and be able to run after putting in an 80% effort.  IMO to pull that off you need to be "competing" at the HIM level and pretty well adapt to the race distance.  If not, IMO 70% is a more realistic number.

Ok, so for someone that has spent all winter training indoors and has no power meter on the bike..... how would you characterize the effort level?

I mean, I know what my virtual power FTP is, but it's completely meaningless as I have nothing to translate it to in the real world.  What should 75-80% of FTP feel like?

Only you are going to be able to answer that question.  If you are training for HIM you should be doing some long intervals at 80%.  You can do that indoors and either record your HR or just memorize your RPE to get used to it.  My coach has me do 3x40's @ 80%  with 10' Rest intervals

What do you have for training outside? Use the trainer time to learn that more effectively, be heart rate, RPE or something else.

Basing race power goals on % of FTP is just a bad thing to do all the way around.

You should base your power goals on training rides of similar duration. Sure, you can look back and say, "I rode at x% of my FTP." but that's not a good way to race.

It also depends on your level of bike fitness. Fitter cyclists can come closer to their FTP and still be able to run well. It also is dependent on the individual. Taking a straight percentage leaves A LOT of information out of the equation.

You have to estimate, unfortunately. YOu can get pretty close with a HRM as long as you're doing long intervals in that FTP range - shouldn't be too far off indoor vs outdoors. I did that before getting my powertap, and with the powertap, it's playing out pretty much as I estimated for those steady efforts. Where it fails are the short accelerations or rollers - HR can't keep up with the quick fluctutaions, so you'll get less reliable data more variable courses. 

Still, you'll learn to RPE what 80% of your FTP is by doing this on rides and can get pretty close.

Nothing. ALL of my training has been indoors via virtual power. Unless there is a major change in local weather & road conditions in the next 5 days, my next outdoor ride will be my race with my last outdoor ride being last August (bike crash, yada, yada, yada). Bike gets dropped off to TBT for shipping before this Saturday, race is on the 17th.

So, I'm thinking that I'm pretty much just going to wing it and try to feather it against the feeling of lactic acid in the legs.

If this is your first HIM (I'm assuming it's a HIM you are talking about) then I would just ride easy.  A pace where you can talk to yourself or maybe hum a song.  Another person from a prior thread gave a good example that you should be able to smile the whole way.  If lactic acid is coming into the picture...you're going way too hard.

Unless you have a lot of experience with endurance training and racing, you are much better off going in with the mindset that the race doesn't even start till the run.  The swim and bike are sort of just necessary warm ups. 

If you read a lot of HIM race reports, how often do you ever see a report from an average AGer who was doing their first HIM and wished they had gone harder on the swim or bike because they were running way too fast?

Racing is a learning experience.  There is no magic forumula that works for everyone so that you have your absolute best race.  You need to learn for yourself how your body feels and responds.  If you can't simulate that with long outdoor workouts, well then you just have to do your best at improvising on race day...try to learn from it, and make small adjustments for your next race.  And I think it goes without saying that you'll likely learn a lot more from a race where you pace it slightly too easy than a race where you totally blow up and end up walking the last 8 miles.

Of course...just my 2 cents.

It's a good $0.02, and that is the kind of thing I've been trying to figure out.  It is my first HIM, and I have been rattling my mind to try to come up with a way to translate my indoor rides to the race, but there's kinda really nothing.  I'm not sure that I can even really use HR because temps are going to be high, so HR will be higher than normal; and the "bike too hard and blow up and end up walking" is exactly what I'm wanting to avoid (of course) as that's what I did in my last Oly, but I also don't want to leave more time out there than I have to. I do realize that taking 5 minutes longer on the bike might save me 30 minutes on the run, however.

I will definitely be improvising on race day.

Fred hit the nail on the head with this one. Where most athletes make the fatal mistake is taking their FTP 20' test and estimating their bike % off of that. You HAVE to factor in the degradation that comes with a swim effort (of any distance, not just IM) and figure your bike pacing off of that. Stronger swimmers that don't use as much energy will not have as big of a degradation as weaker swimmers that burn through A LOT more energy due to inefficiencies in the water.

One test that I like to do is a 1500m swim wearing a HR strap/watch at race pace (this gives a ball park of how much energy the athlete is using during the swim) followed immediately by a 20' TT (FTP) Test. A longer bike test would be more accurate for sure but this at least gives us a starting point to figure bike percentages. A lot of experimentation during the long rides/long bricks also will help to refine that wattage range that will leave you with legs for a good run.

Good insight on the HR issue.  There are a lot of factors that come into play when you are trying to translate trainer HR to race day (outdoor) HR.  Where your trainer is set up might be temperature controlled, but unless you've got a couple of industrial fans blowing on you, it's possible you're likely not getting as much ventalation and cooling from moving air as you would outdoors.  Also, your race day HR might be a little lower on race day for a given RPE because you are well rested (tapered), or it could be a little higher because you're mentally/emotionally "jacked up" with excitement.  Again...these are just some things you have to work out with experience, and it's also why you should always be willing and capable to adjust your metrics on race day depending on weather variations or simply how you feel.  You'd like to think that you're going to always feel 100% on race day, but that's just not going to happen all the time.

As to the bolded, since most of us are racing for "fun", never underestimate how much more enjoyable a race can be if you hold back a little too much compared to if you go a little too hard...even if both efforts result in the same finishing time. 

Lastly, I don't care how fit you are, the last 6 miles of a HIM run is going to be mental.  You would like to think that you can simply ignore the outside factors and run your own race, but you can't deny that you mentally respond better when you're constantly passing people (because you raced conservatively early on) at the end of the run compared to being passed (because you pushed it a little too hard and are now fading).  If you can do things to help you win the mental battle when it counts, your body is more likely to perform to your expectations.

Best of luck to you.