wankel engine or normal engine

[JonGwynne]

funkihamsta said: I would have thought it impossible to alter the compression ratio, without altering the shapes involved. Kinda the equivalent to altering the compression of a piston engine by trying to fit square pistons.

Also l'm pretty sure that rotary engines are basically knackered after 100,000 miles, unless they've been rebuilt. (yum expensive)

In the US, it is not unusual for a rotary engine to go 200,000 miles before needing new apex seals (equivalent of piston rings).

The trouble is that if the engine has been overheated, or if proper coolant isn't used religiously the rotor housing (equivalent of engine block) can crack and that's where the big money starts to come in.

However, I've heard that UK petrol additives can corrode the seals and rotor housings leading to premature wear.

The good news is that if you find someone who knows what they're doing and if all you need is a new set of seals, the rebuild can be pretty inexpensive. The trick is finding that person. The guy I used to take my RX7s to used to refuse to rebuild the engine on any but his own family's cars. He said the procedure can be simple or it can be horrendous and there is no way to know until you're done. he said it could take anywhere from a couple of hours to a couple of days depending on everything.

[funkihamsta]

Hmmm interesting point about the rotary rebuild expense. i.e. not a lot really if you know what's what. Ignorance costs money, same for anything l suppose. I've noticed that most RX7 are cheap as chips with only 80-90k on the clock. Why sell so low makes me suspicious...

[andytk]

F.A.O JonGwynne

You said in an earlier post that you were looking for some info about the early rotary engines.
While rummageing about the internet I stumbled across this site

www.nsumotor.onlinehome.de/dkm.htm

It may be of slight interest to you

Andy