I get my facts from a decade and a half of building tuned Hondas of all shapes and sizes and have having been in thousands of actual street races a consequence of living 3 miles north of mission and miliken the home for street racing in so cal, for all of my driving life not some idle chit chat on a forum.

For a s2000 to make 215 whp especially on a dyno jet stock is impossible not even an ap2 - anyone who tells you this is giving you false information. At sea level with properly inflated stock tires and decent 92 octane fuel with the low ambient temps you will still lose 25 to 30% of your crank hp to the driveline. 240x.25 is 60hp thats 180 whp if it's 30% it's 240x.30 or 72 hp for a total of 168whp. The inconsistency between drive line loss is due to the tread design actual psi and more importantly alignment specs.

The only way 215 whp is possible is on a dyna-pak without correction to standard - call CAT or KN or AEM they will confirm this. Since the dyna-pak measures hub output and not actual at the wheel output the loss will be between 15 and 20%

I've seen lower drive line loses depending on fuel blend and break in sometimes as low as almost 20% but that still puts the car at less than 200whp. My friend says he sees alot of them in the low 190 to mid 180 range at there shop in riverside.

Magical things would have to happen to your engine like a nitrous install to see 215 whp on a dyno jet.

Now let's take a track like AAA which is at a mere 1200 feet approx and is indicative to standard elevation still rates for a nhra correction figure

Track Elevation ET (Elapsed Time) MPH
1200' .9874 1.0129

so if you ran a 14.5 @ 95mph with Lotta wheel spin as AAA can be slippery you corrected sea level run would be 14.5x.9874 = 14.32 @ 95x1.0129 = 96mph

Those same correction factors were used btw when the s2000 was originally run at Pomona 20 miles west - the s2000 as tested by most was slower actual than shown. And they have as many tries with a prepared surface to get it right.

Now for the car - you are assuming he is simply swapping out the motor and nothing else.

I on the other hand will assume if he's challenging the s2000 he has at least i/h/e and maybe hondata s100 tuning now your not talking 150 whp your talking 170whp this is pretty standard fare.

Also if like most ricers he's ditched the ac and ps system install your dealing with up to another 7-10 whp with timing advance thrown in which when added to the lighter header and exhaust drops the cars weight down considerably as does removing the spare and whatever else. Track dc's with full cages can dip below 2100 with driver so this is hardly stripped.

I see cars like this all the time roll over the scales with an empty gas tank as raced in the mid to low 2400 range with driver, my last 4 door with b16 swap and full interior was 2420 with driver. crappy Slip streams with aftermarket tires can chop 80 pounds from stock in some applications - plus lighter drop suspension, brakes a racing bucket a battery steering wheel. These are pretty common items and add up to a tremendous amount of weight loss.

As far as the tires go somewhere online is the now ancient SCC article testing the NT555R tires on a stock gsr which gained 1.1 seconds and a stock prelude vtec model which gained a ridiculous 1.5 seconds in the 1/4. 1.1 seconds from 15.2 btw is 14 flat with no other mods. That article is now well over 10 years old and even the azenis so called by ricers "cheater slicks" are that capable. If he has proper slicks which are easy to come by the gain will be even more.

You can debate numbers all you want but I've seen s2000's lose to these types of cars @ AAA drag way on a number of occasions.

To the OP I still think you should race not for dollars but definitely from a rolling start. You might lose but so what racing is still fun and you still have an s2k and he still has an Integra.

BTW you should be incredibly careful about relying on what should be instead of what you've actually seen - the standard drag racing calculator shows that a stock s2000 with 240 crank hp and 3000 pounds with driver weight should run a 13.5 1/4 mile stock.