gotorx7

I was taught NEVER to Rev an engine before shutting it down, as the extra fuel washes all the oil off your moving parts. Next start is Metal on Metal - hence accelrated wear.

I can see no reason this would not apply to Rotors except maybe that we are also injecting a little oil with the fuel.

I never do it anyway

gotorx7

I was taught NEVER to Rev an engine before shutting it down, as the extra fuel washes all the oil off your moving parts. Next start is Metal on Metal - hence accelerated wear.

I can see no reason this would not apply to Rotors except maybe that we are also injecting a little oil with the fuel.

I never do it anyway

ech

I think an extreme position is being taken here. I agree there is little point to this practice, but lets come back into reality. Unless you key-off w/ foot on throttle, it also shouldn't cause any harm. Come on ... 3K-5K under no load is NOT going to put heat into the turbos - which are water cooled anyway. The almost non existant fuel at that load is NOT going to leave the engine housings bare of oil - after all the OMP is still running.

It's still a silly practice, but harmless.
But hey. I think turbo timers are a placebo - so maybe I just don't fit in.

tmiked

Even 3 - 5K with no load puts a lot of unnecessary heat into the turbos.
Let it idle then cut clean.

I agree turbo-timers are snake oil, unless you are to undisciplined to drive you gar gently the last few miles of a trip. At the strip or autocross, just let it idle a min or 2 while you stand around.

DrunkenBowler

First off, anyone who rev's the car before shutting it off is an idiot.It hurts the car (particuarly the turbos) when you do that. You do not want to spool up the turbos or heat them up before shutting them off. To do so is stupid. Unless you want to run your turbos into the ground and pay for a rebuild or new turbo(s), then you can rev all you want.

paw140

I thought that they used those ignition switch things that you clip onto yourself, so if you fly off the bike it will kill the ignition. They really don't idle on their own?

enuttage

Well, sure enough after all this talk, I had cold start problems yesterday, and sure enough my plugs were fouled.

City traffic and not enough opportunity to really spin things up is probably at fault.

These plugs are not for me.

But, I also understand completely why my mechanic has me do what I do. I'm running so rich at idle that it IS a good idea for me to rev it up.

As many times as I can be called an idiot in this thread, I just don't think I am.

Well, actually I am, for buying race plugs, knowing that I'm living in a very urban area.

Is anyone running the plugs I mentioned earlier in this thread? If so, tell me if you've had problems keeping them clean. If not, then instead of calling me an idiot, try and find some evidence that revving to 3K will NOT help me keep MY plugs clean.

For easy reference again, they are NGK NR6725-105s.

That would be extremely constructive.

-E

enuttage

p.s. Jim, would you consider those "racing" plugs?

gotorx7

Firstly, I'm not calling you an idiot

Why are you running so rich at idle?

I can't see that revving to 3K will do anything at all to keep your plugs clean - when you open up the throttle, you're going to pump more fuel in there (even if it is a bit leaner), and if you just kill the ignition then, you are going to have amounts of UNBURNT fuel floating around - that can't be good for the plugs. And if you get off the gas and let it come back down to idle (briefly) before shutting down, you are still going to be in a rich condition aren't you?

If it were mine, I'd be fixing (what sounds to be) the real problem - too much fuel at idle

adam c

iTrader: (2)

If you don't want people to think you are an idiot, don't put your picture in your avatar.

I am using the NGK 9s. No problems.

enuttage

Too much fuel at idle is from the street port and 850cc primary injectors, apparently.

My understanding is that the extra spin up and burnoff after revving it up should burn off any overkill on the fuel side.

And, FWIW, I'm not letting it come back to idle after revving to 3K. I kill the ignition at 3K.

Let me know if I'm misunderstanding something. My tuner is fairly well-known in these parts for doing a great job, so I've got to think there must be some logic to what he's saying.

But I really want to try and understand why you guys think it's kinda dumb.

Still wanna hear from Jim if I have "race" plugs or not. They're labeled everywhere (RP, etc.) as such, but that doesn't necessarily mean anything.

Thanks for any input.

-E

p.s. goto. Sorry if it seemed like I was talking about you. I wasn't You've been very constructive here. Thank you.

enuttage

If you don't want people to think you're an idiot, then don't assume that's me in my avatar.

And I fail to understand why you continue to insult me when I'm trying to learn. If you want to be a dick, just e-mail me and stop wasting space on the board.

-E

kagegod

To the person who said his neighbor has an Eclipse GT, next time he revs it tell him no matter how many times he/she revs it he/she still drives a DSM. If they know anything about cars that should shut them up

Doesn't
Start
Much

DamonB

These are different than the NGK NR6725-105 the enuttage says he is using, no?

adam c

iTrader: (2)

That was a joke. I guess you didn't get it. I actually like your avatar........don't tell anyone I said that.

I'm not trying to insult you. I am saying that the practice you have been told to do is dumb. Why don't you stop doing it, and see if there are any bad effects. I think you will find that everything is fine.

My plugs are the NGK (BREQ??)9, or something like that. The 9 is the heat range. It is a mildly "cold" plug. The 10 or 10.5 that enuttage has are even colder plugs. Probably race plugs. Maybe not the best for regular street driving.

enuttage

a) I am not running 9 plugs.

b) I am running colder "race" plugs.

c) Because my plugs are different than yours, it's possible that I may need to take different precautions to preserve them.

d) I'm trying to find out if there is any merit (or better yet why there would be any lack of merit) to what my mechanic is telling me to do.

e) I have yet to receive a definitive answer that doesn't involve my mechanic being a cheat or an idiot. I'd like to know why some of the more experienced tuners/wrenchers on this board think he might be having me do what I'm doing (the 3K rev).

adam c

iTrader: (2)

A number of experienced members, including myself, have responded. Most everyone has told you not to follow the mechanics advice. Maybe you should call Petit racing, Pineapple racing or another well known rotary shop to satisfy your curiosity. Let us know what they say.

ech

Who has a pyrometer? I'd like to challenge the assertion that say 4K revs for 10 seconds (pick your test), in nuetral, puts a "lot" of heat into the turbos. How much?

And even if it does - so what? These things can gen. 15+ lbs of boost, and glow red hot while running. The danger is coking the oil on the bearings after you shut off- which is a bit overblown because that mostly happens w/ non water cooled turbos. The water won't let the oil fry, normally, and just making the oil hotter isn't going to coke it - it has to get REALLY hot.

So assuming you are reasonable and let things cool down a bit after a red-hot run, there isn't much you can do that will really be bad for the turbos IMHO.

jimlab

You should have four. Better check.

No, you're just running cold plugs. I wouldn't even call my 11s "race" plugs. They're just a colder plug than stock.

It's also possible that your mechanic doesn't know what the hell he's talking about, a possibility you don't seem very willing to entertain.

You can believe you're right without being right, and still sound totally credible to others while spouting misinformation.

In all my years of driving and car ownership, let alone rotary ownership, I've never run into anyone who advised revving the engine right before shutting it off, nor can I think of any single rational explanation for why this would be beneficial.

Instead of looking for reasons not to follow your mechanic's advice, perhaps you should be searching for logical reasons why you should.

I'm still voting for idiot. I've seen enough mechanics who thought they knew more than they did that, combined with my opinion of his advice, I have no other choice. His advice doesn't make any sense. It may not hurt, but it's also extremely unlikely that it's doing anything to help.

enuttage

Oh my god! Thanks Jim! All this time...

Thanks for the opinion I was waiting for from you. RP and at least one other online vendor claims my plugs are race plugs, but that doesn't necessarily mean they are, of course. Misnomers for marketing's sake may be involved.

You're right. He may not. And you're also right. I'm not. He's made my car progressively faster, run cooler, and perform better for my applications, the longer I've been going to him. But that doesn't mean he's necessarily right on this one.

The feeling is mutual. You can spout the same misinformation, and you do a damn good job of being convincing and seeming credible Jim, whether you're right or not.

Thank you. That is, in part, what I was looking for from you as well.

Um, that's what I'm doing. I'm following his advice and per the impetus of this thread, I'm trying to reaffirm that it's the right thing to do.

Well, I know he's not an idiot, but he may well be misinformed on this one. The last sentence you wrote is taken to heart. It may be that it really isn't doing much of anything. Certainly it hasn't saved my plugs! But there are a whole 'nother set of factors that could've played into that as well.

I took Adam C's advice and shot a couple of reputable shops I've worked with before e-mails about it to see what they think. It'll be interesting to see their take on this as well.

-E

Rx7aholic

iTrader: (22)

Well guy's Rotary's always have a little unburn gas stays inside the engine & exhaust side, I think someone already mention this it's only to burn off the excess gas left in the engine.. Also I always rev mine up to 2000 rpm especially in the winter months make' it easy to start without flooding it. Btw I hope many of u know that Rotary works the opposite of a piston engine?

gotorx7

No, I didn't know that...

Tell us exactly what you mean by that will you??

apexkw

um i never do that and i have never heard about anyone reving there engine before turning it off.

BicuspiD

...pulls up a seat

LetsGO7

iTrader: (2)

I don't know if anyone answer the question to the thread but i guess I will or will again. They rev it cuz i think they were told to but the reason is to get oil to all the parts of the engine lube when shutting off. If you let it sit there idling the engine gets stuck with hot dirty oil...but when you rev it and shut it, batch of clean (filtered) and cooled oil will be in while it sits. This idea is for rotray and piston.

-joe