Remap questions

[tameracingdriver]

Right, I see a lot of people on the forum have remaps. I note that they seem to improve drivability and also increase the rev limit.

Now, I have my blueflame exhaust and soon will be going for an induction kit (simota probably). After that, at some point, I was considering going for a remap, but I have some questions, which, after a quick search of the forum, dont seem to be answered anywhere before (or maybe i missed it).

How well can these cars take to being remapped? Clutch? Gearbox? Engine? How well can it take the strain of being remapped?

However, I am even more curious about the increased rev-limit. I am inclined to believe that Renault set it to 7200 rpm for a reason. What makes everyone seem to believe its safe to allow a red line of nearly 8000 rpm? Surely this cannot do the car any good whatsoever?

Answers on a postcard.....

 

[Mr.AdamB]

hmmm well every engine isnt set a peak performance maybe to keep it with in certian laws, regultions bla bla so there is room for improovement, or to turn up the power.

remap just increases the fuel and air mixtures and raises the rev limit thus giving it more power.

yeah the limit it set where it is for a reason which is the engines peak with otu conprimising a % of relaibility as they have to keep them to a warrenty ( IMO )

but as everything in this world if u over work it or turn up the power there will always be more wear etc, thats y you can replace internals etc which are stronger and can take the extra power. but most engine should be able to handle over there rev limit with no problem.

for example i take mine to 7500. hassnt blown yet ( touch wood) but i can take it higher as its set at 7800 but i scared as i feel as if its screaming at me in pain. lol

its not safe, to redline at 8000 rpm lol but it gives u that mure more power. and people loive power so u tend to rofget about everything else.

meh but wat do i know? heh

 

[BenR]

Remapping itself serves the only purpose of smoothing out the torque curve and bumping it up a few lb.ft, there are no large extra strains and the engine gearbox can take much more than a remap can hand out, so you should have no worries there.

The RPM limit on the other hand is an area of interest. 7200rpm is the factory limit yes, and power tails off at 6800rpm anyway so pusing 1000rpm beyond that gains very little in terms anything and will actually make you slower as the torque curve drops off like a stone past 6800rpm. Also to note, cup racers are limited to 6800rpm as it is common knowledge that spending time above that constantly (ala track cars) WILL lead to piston failure of a catastrophic nature.

 

[ant]

its not safe, to redline at 8000 rpm lol but it gives u that mure more power

unlikely from the graphs i've seen.

the power curve has peaked well before 8000K!!


the benefit though is that you're higher up the rev range in the next gear i guess?

 

[ant]

beat me!

 

[BenR]

but your also got that much less use of a building torque curve than before.

Shift early and your on a raising torque curve, shift late and your on a declining one.

 

[Mr.AdamB]

how i see it is that u take it higher revs and it drops u higher in the power band, thats y it give u better acceleration or no one would bother raising the limit.,

 

[BenR]

yes, it will drop you back into a positing high in the powerband.

But thats where looking at something wholistically is better than with tunnel vision.

When dealing with accelerationg you have to look at the ratio of bhp gain upto peak bhp, and the ratio of bhp loss after peak power. If the ratio of loss is higher than the ratio of gain, say 500rpm after peak power, then it would suggest it is more beneficial to shift up and move back into a point of higher acceleration.

And in case with the 172/182..after peak power (6800rpm), the power drops off like a stone.

 

[Lagerlout]

Whilst I can't add to the technical side of things, I can say that when I had my GroupN ECU I very rarely used the extra revs. I'm sure I could feel the power (torque?) taling off and would change round about 7k - That seemed to drop me just nicely in the meat of the next gear.

Only time I can see it would be really handy would be on track i'e holding a gear inbetween corners for those few extra revs.

Although having said that, whilst ....erm.... 'comparing' my car to another 172 I noticed that holding fourth up to 7,800 rpm allowed me to pull a bit of a gap on it.

The rev limit for me was nothing worth bothering with really. It was the increase in thottle response and the swell in midrange torque that made the biggest difference.

 

[BenR]

a good driver will be able to feel when torque drops off and you should shift up, so your correct laingo.

 

[Lagerlout]

Well I'm certainly not a good driver. lol. But I'm pretty sure I feel it tailing off. On the odd occasion I did utilise the extra revs, I certainly didn't feel there was any extra power to be had. In fact all it did was sound strained and f**king rough. lol

 

[BenR]

they do sound harsh at high rpm.

 

[Paul_P1]

Seem to remember that my bro's old R-Sport'd Cup making well over 170bhp fly(maybe more), right to the limiter, surprised the operator at Dastek.

 

[Mr.AdamB]

meh i find i accelerate alot betetr taking my revs to 7500 than changing at 7.2 in my valver...

 

[BenR]

meh?

 

[Mr.AdamB]

dunno.... diddnt even realise i wrote it o well! meh!!

 

[Paul_P1]

LOL @ meh!

 

[Mr.AdamB]

meh!

 

[LegoHead]

eh eh errrrrr

 

[Mr.AdamB]

anyway back on subject!

why do people raise the limiter if it "slows u down" heh

 

[Thomss]

P Murray from rstuning did a nice job on mine,feels better in lower revs and raised the limiter to 7800 which I don't use that often at all but find my self hitting the limiter far less than I used to. Glad I had mine done.

 

[BenR]

raised limiters, as stated, are usefull for holding a gear during a corner rather than shifting mid corner, or short shifting before the corner.

whats so hard to believe, every power graph will explain.

I notice you have a valver, and not a 172/182 which has the vvt retarded at 6800rpm.

 

[tameracingdriver]

Also to note, cup racers are limited to 6800rpm as it is common knowledge that spending time above that constantly (ala track cars) WILL lead to piston failure of a catastrophic nature.

So far, this is the only comment that has really touched upon what i was trying to ask. If this is anything to go by, then it would seem that indeed, there is a chance of engine failure if using revs higher than the car can handle.

 

[TheJesus]

what about on throttle body setups Ben, what's a safe RPM limit on a standard bottom end?

which email you on today too bud, got a few questions. home or work??

 

[jooliona]

is it worth bothering with a remap if u've not done any engine mods?

 

[Dubai182]

I have a group N jooliona and only have a ITG panel filter and a decat but more mods on the way. The ECU has definately added a little zing and it seems to gain harder after 5k. BUTTTTTTTT at the moment it's causing a nightmare with my AC.

 

[jooliona]

zing sounds nice but is there a solution for the AC problems?

 

[Dubai182]

No one else seems to be suffering from the AC problems so i'm not sure whats going wrong with mine. It will work after maybe 20 minutes of driving or it works and below 60mph.

It's going in for a service within the week so i'll see whats going on then.

 

[Englebert]

But won't the dealer just reflash the ECU to OEM spec?

 

[182 sport]

id only go for a remap of youve got a derv.no point on a petrol with no turbo.

 

[Rich_MC]

remappin sounds good, now where can i get it done lol and how much ;-)

 

[7MAT]

remappin sounds good, now where can i get it done lol and how much ;-)

www.superchips.co.uk

off the shelve map £300
custom re-map on rolling road £350


Edit: Just seen that you have a 1.4, not 100% sure they do them for non-rs models.

 

[Rich_MC]

fink i went on there before mate, said i would gain an extra 5 horses, thats harsh lol

 

[Lagerlout]

id only go for a remap of youve got a derv.no point on a petrol with no turbo.

Sorry, but that's b****cks.

Sure, you're not going to make an extra gazillion horsepower like you do with a derv but the driveability and power delivery can be much improved - Made the single biggest difference on my car.