Jump to content
SAU Community

Recommended Posts

this is how it works

you get to choose from

Fast

Reliable

Cheap

Pick two.

Fast + Reliable = Not Cheap

Fast + Cheap = Not Reliable

Cheap + Reliable = Not Fast

lol

I always thought that people blow rotaries because of modding without a tune? Because they are MAP based arent they? So adding free flowing exahausts, intakes, intercoolers etc and not compensating for the extra airflow = lean. Bang?

  • 2 weeks later...

Not necessarily so, my (work) holden rodeo ute pings badly in the upper rpm when i floor it and it has 230, 000 ks on it, has been doing it since I first started driving it at 70, 000ks

Not necessarily so, my (work) holden rodeo ute pings badly in the upper rpm when i floor it and it has 230, 000 ks on it, has been doing it since I first started driving it at 70, 000ks

because race car...sorry I mean because Holden...same thing really :P

because race car...sorry I mean because Holden...same thing really :P

Nah, the only holden thing on it is the badge

All isuzu running gear, cant adjust the timing on

tthe bastard , its only the 3.5 litre that does it, the

3.2 litre doesnt do it

Edited by StevenCJR31

detonation (ping, knock etc), as a general rule, is only highly destructive on a motor depending on its power output per cc (engine size). Basically because for higher output per cc you need a bigger, more powerful combustion charge (and usually compression) so if this charge detonates (pings) the cylinder pressure is waaay higher (and usually hotter) than a detonation in a motor with lower power per cc. Hence why old clunker, low power reliable cars can have detonation and not get upset and live a long time. While you have detonation in a high output motor, esp a boosted motor (very high output per CC) it will kill it quick.

Having said all this, im not sure what detonation would do specifically on a rotary motor to hurt it as I don't know enough about them.

all I know is that they sound sick and can run an epic 1/4 :P

The rotary combustion chamber behaves nothing like a piston engine, hence detonation is almost a non-issue on rotaries (apart from highly boosted rotaries). The volume in the combustion chamber increases rapidly at the beginning of the power stroke due to the nature of the epitrochoidal motion of the rotor. A piston engine's combustion chamber volume increases very slowly at the start of the power stroke, meaning that any pressure spike can have adverse effects on the piston engine.

This phenomenon means that it's much harder to induce detonation in a rotary engine, as the volume increases at a rate where the effect of pressure spikes very much reduced.

NA rotaries generally don't suffer from compression related detonation, and in fact anyone using anything more than 91 octane in a NA rotary is most likely wasting money. Turbos, on the other hand, - well, turning up the wick too much can destroy any engine.

Like any engine, a properly maintained (and sensibly modded) rotary will last a very long time. The last gen RX7's are a fantastic package, and sure to impress. Like with any 20 year old performance car, you can expect to see a lot of badly maintained ones, which will be lemons. No worse than any other performance car of the same vintage though.

Edited by warps

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • I'm actually not sure - I think it was "Stealth Performance" (It really is near impossible to find a FEMALE 1/8BSPT to 1/8NPT male at ALL) but having the thing leveraged on a 90 degree angle on a small aluminium fitting is not too smart. Also in not too smart, I've drilled out the center of the broken fitting so there's maybe 0.00001mm of thread to bite into, so yeah. I may have to get it drilled/tapped/plugged entirely. Given I could conceivably tap a thread/adapter/pressure line in any point in the oil system I suppose it's feasible to run a line to the Nissan Sensor to keep the dash working. Do these exist in AN fittings and the like? Like an AN fitting that has a NPT (or other?) thread as well for putting a sensor in?
    • I would agree.  There will be an amount of boost you could run safely with an otherwise factory system, but it would be low enough to not be worth the cost.  And if you are reliving your 20s, you know a 'little bit' was never enough. Personally, if I didn't want to spend the money, then stick with NA bolt-ons, and maybe a tune.
    • Fuark, at least the motor survived. What brand was the fitting that snapped?
    • Wrong question. There's no point in spending the rather large sum of cash and effort to add turbo, without taking it to the "sensible" limit of the motor itself. If you have to upgrade injectors, etc, then so be it. That is a tiny fraction of what it will cost you to turbo it.
    • Measure voltage at the starter solenoid terminal when the key is at start and it has clicked. If it is really low, then the suspicion falls on the ignition switch (contacts or wiring thereof) as causing a voltage drop instead of sending enough volts to throw the solenoid all the way to engage the starter itself. If it is a decent voltage, then the suspicion is on the solenoid. Might have s horted coil, or might hva dirty contacts. Rip the starter off, dismantle, clean up contacts and inspect winding. It might not be possible to see if there is a short in the winding though. I have a spare starter here that I could measure the resistance of the coil, as a guide to about what it should be, if you need a comparison. <parts hoarder>No you cannot have it.</parts hoarder>
×
×
  • Create New...