I have a stock f20c with 125,000 miles making over 600whp. And even I know the f22c is a better engine. Wether all motor or boosted the f22 just makes more hp and tq everywhere in the power band even in the top end of the power band.

 

"Better" meaning it will make more hp and tq. Some folks are not concerned about a bit more hp and tq.

 

Better manufacturing process, better retainers (though these can be switched out), better crankcase ventilation (also can be adapted to the f20).

The F22 starts out as a better engine. The HP and Torque bumps are nice as well.

Would I swap out a good F20 for a F22? eh...probably not. but maybe.

But if I'm already swapping the engine....why not buy the better one? What arguments are there for the F20? 9K redline?

I'd MUCH rather have a factory assembled used engine than an average rebuild.

 

Agree!

 

Just out of curiosity - is there any data out there regarding overall reliability of the various s2k engines?

 

Reliability of each model-year versus the others? Or reliability of the S2000 engine versus other similar sized sports car engines? I think we know the answer to the second question.

 

I meant to ask if there is data comparing reliability of the engines in the various s2k models, not other cars. I agree, we pretty much know about s2k reliability v. other sports cars.

 

Well...probably not formally.

For 00-02 engines, you'll find failures from oil banjo bolt issues...and I think valve guide issues on some 02's.

For 00-03 engines, you'll find blown engines from cracked retainers. A great majority have been over revved, however. You'll also find oil consumption issues.

For 06-09's, you'll find valves that tighten up.

04-05's don't seem to have inherant issues.

Some result bias would come from the fact that a lot more AP1's were bought by people who tend to beat them up. But some of it is obviously from design improvements that happened on the F22.

This does not count driveline issues (clutches, synchros, etc) that also were addressed with the F22.

 

The one area of reliability advantage of 04-05 over 06+ is the 06+ issue with exhaust valves becoming tight much faster than other years. If neglected, or even just treated like the other year S motors, you'll get burnt valves.

However this is easily remedied by shorter valve adjustment intervals, as well as the adjustment values used. Just so long as you start doing this before you burn a valve.

In addition, a Flashpro tune can reduce the running lean that is the root cause of this issue (while simultaneously providing the best bang for buck performance improvement available in the whole S range).

Therefore, imo, no reason to prefer the 04-05 so long as you know about this, and provided the 06+ you are looking at doesn't already have a burnt valve, which is admittedly not easy to tell (though solid compression test numbers are a decent indicator.)

 

I've only ever driven the AP1