Hi,

I recently bought a '93 R1 with 3300 miles on a Pettit Racing engine rebuild. It's currently running on stock boost and has an aftermarket ecu and most reliabilty mods (precat removal, aftermarket radiator and intercooler, silicone hoses, AST removal). It runs on 93 octane fuel and is currently using synthetic oil.

Yesterday my brother took it for a drive without my knowledge. He let it idle for 2 or 3 minutes in the driveway before taking off, but I'm not sure if he let it warm up to operating temperatures before getting on the boost. What kind of damage could result in going above 3000 rpm before the engine is warm? How can I tell if this type of damage has occured?

Thanks!

 

Are you experiencing any type of symptoms to lead you to thing something is wrong with the engine? if not then all should be good. But for more reference go luck under the FAQ sections for the 3rd Gens, it provides information on your question.

Had the same thing happen to me as well, but nothings wrong with the engine, and still makes good compression. for peace of mind do a comp test to see if your apex seals are still good.

 

welcome to the board.

just to repeat a little of what was said. you're probably okay. obviously you shouldn't make a habit of it, but this type of thing is accounted for in design. it's just a better idea to have all parts (metals) and fluids up to "normal" temperature for them to perform optimally.

 

^Agreed with the above. It's not a HUGE deal. Besides, if he let it idle a few minutes, it was probably pretty warm.
Not sure about your re-flashed ECU, but on the stock ECU, the car would hesitate badly at transition under boost if it wasn't at full operating temp. I don't think that was intentional by MAZDA, but it tended to remind owners to wait before going full boost.
Now...go thump your brother for borrowing the car w/o permission.

 

I have a FC non-turbo, yea way different car, but I let my buddy drive and i was passanger, it was like 15 degrees out and he decides to floor it before letting it warm up even 15 seconds..... a few minutes later the coolant buzzer starts going off..... Boy was I upset!!! Lucky it was not anything major.... LET THEM WARM UP!! Guys!

 

isn't warming up all about the water jacket seals? they need to expand and bed down around the whole engine (not just the combustion/exhaust side) before too much pressure is put on them otherwise they can get popped out of the groove?

i could be wrong.

either way, i'd say a 3 minute warm up is sufficient. i know plenty of rotaries that've been driven cold on start up once or twice with no immediate or terminal damage.

if she still runs nice and isn't using water then don't stress, i'd say.

ps - your brother is probably stretching the truth with his warm up time, he probably sat there for a 30secs adjusting seats and mirrors before he booted it out the driveway. haha

 

^The rotary is a bi-metal sandwich contruction. Different metals heat up (and expand) at different rates. Especially on forced induction (higher combustion chamber pressure and heat) you want everything warmed up first.

 

My EX girl friend did this to my RX7 D: it didn't hurt it but i did a compression test to be sure and everything was fine... Except for the girl :P

 

As said it's probably fine but you don't want to make a habbit of it. Running it hard without proper warm up will also cause additional wear of the bearings. Also the best way to warm it up is actually driving it under *light load* not idling in the driveway. Drive it around the block a few times like grandma instead of idling.

 

Zero damage will occur by driving above 3000 RPM with the engine cold. None at 4000 RPM, nor 5000 RPM, nor 6000 RPM, nor all the way to redline. Not that I'd ever recommend taking a cold engine of any kind of redline but you're not going to damage the engine.

Now, doing such at wide open throttle wouldn't be a good idea, but should not damage the engine either (certainly won't be good for it!!) if the tune is safe. In fact, if the engine is properly tuned on a capable ECU then there should be a temperature/throttle position referenced rev limiter to prevent this stupidity.