Variable rev limiter

[dandycaptain]

Ok, picture the scene... I've been in my 182 for 15 minutes or so (driving) and it's well up to temperature. Not been thrashing at all, just cruising along. I stop at a post box, turn the engine off, get out, post the letter, get back in, start it up, put my foot down to get out into a gap and the bloody rev limiter cuts in at 6.5k. EH?? Obviously I don't really wanna be hitting the limiter, but it's happening quite a bit lately when the gauge says the engine is well up to temp but the rev limiter is still cutting in too early. Is it just mine or is it meant to do that? Is it to do with how long the engine's actually been on for since it was started that particular time, regardless of temperature?

P.S. I never rev it hard when it's anything but up to normal temperature!

 

[mattjk]

Your thinking of the water gauge which gets hotter quicker than the oil i dont believe the limiter is removed til the oil hits 90c

 

[-Leigh-]

Yeah it works on oil temp, not water temp.

 

[DrR]

Wish they came with an oil temp gauge.

 

[dandycaptain]

Aaaaaah. Right. Just to be safe in future I'll change up at 6kish from now on on the odd occasion I need to hustle, unless I've been out for a while. Cheers for the replies.

 

[eggy790]

how hard is it to fit an oil temp gauge?

 

[mattjk]

not to hard i wouldnt have thought. Never done one before but all you need is power and the oil feed i dont know where the best place to put the sensor is though

 

[James105]

can't you get a sandwich plate which goes before the oil filter?

 

[bmh.01]

Your thinking of the water gauge which gets hotter quicker than the oil i dont believe the limiter is removed til the oil hits 90c

Yeah it works on oil temp, not water temp.

Nope, they work on coolant temp. Once the coolant is up to 75c the VVT is enabled and the higher limiter is set. I've seen mine have the coolant temp gauge in its normal position and been driving it for 15 mins and the low limiter will stilll cut in, the over rev warning light will come in earlier as well.

You've got to remember thats a coolant temp gauge not and oil temp guage and the oil takes longer to warm up than the coolant does, just give it some more time before giving it some stick.

 

[-Leigh-]

Yeah it works on oil temp, not water temp.

Nope, they work on coolant temp. Once the coolant is up to 85c the VVT is enabled and the higher limiter is set. I've seen mine have the coolant temp gauge in its normal position and been driving it for 15 mins and the low limiter will stilll cut in, the over rev warning light will come in earlier as well.

You've got to remember thats a coolant temp gauge not and oil temp guage and the oil takes longer to warm up than the coolant does, just give it some more time before giving it some stick.

Oh I see. Shame, thought it would make more sense going on oil temp.

I thought the VVT was active from about 1,250rpm? Or am I getting confused?

 

[bmh.01]

The VVT advances the inlet cam timing 16degrees between 1800-6800rpm, but only once the coolant temp is above 75c.

 

[bmh.01]

Bottom here: http://www.getflat.co.uk/pics/3286A-88.pdf

 

[-Leigh-]

Interesting, thanks.

 

[mattjk]

Really!! I was always told it was the oil temp, my apoligies for giving out duff info.

My redline doesnt rise til the temp gauge hits nominal+about 5-10 mins. Seems strange

 

[bmh.01]

Yes it is, i've seen mine do it a few time. Its definetly based off coolant temp as there's no oil temp sender on the engine and that page is from the renault manual so its the gospel (or should be it is renault lol).

I do have doubts over the accuracy of the coolant temp gauge and the temp the ecu actually sees.

 

[GordonD]

The VVT advances the inlet cam timing 16degrees between 1800-6800rpm, but only once the coolant temp is above 75c.

Are you ABSOLUTELY CERTAIN the initial advancing of the inlet cam is dependent on the water or oil temperature?

 

[bmh.01]

Actual cam phasing no i'm not, looking through the docs I believe it is not limited by engine temp and that it functions all the time the engine is 1800-6500rpm.

I am 100% sure that its water temp not oil temp for the higher limiter and the other associated functions as theres no oil temp sender on the standard engine and the docs state coolant temp limits max engine speed.

 

[Fastchip]

The VVT advances the inlet cam timing 16degrees between 1800-6800rpm, but only once the coolant temp is above 75c.

Are you ABSOLUTELY CERTAIN the initial advancing of the inlet cam is dependent on the water or oil temperature?

Yes. Off course this can be changed.