"freeing up revs" can someone explain what this means please?

[1ntense]

Ive heard the term a few times now but dont really know what it means, could someone explain please?

Cheers

Danny

[-Alex-]

Standard engine the revs are heavy.
Free'ing them up with breathing mods typically makes them lighter.

Hard to explain really.

[Kev_Vtec]

breathing mods and a good exhaust system will make it rev alot more lighter.
aka it will rev faster and rev down better and should make more power.
ive been told free'ing it up to much will sometimes make it slower.
i could be wrong.......

[Ashleyp]

Throttle boddies

[1ntense]

think I get it, thanks

I think thats the problem with my VTR, revs are too heavy.

Would a centre pipe and back box free up some revs?

Im thinking about this..

http://www.kamracing.co.uk/index.php/citroen/citroen-saxo/saxo-exhaust/full-exhaust-systems/kam-racing-supersprint-race-system-citroen-saxo.html

or would I also need to de cat it with a 4-2-1 mani to really notice much?

[Ashleyp]

a good decatted system would help

however, the 8v engine's torque peaks at 3300rpm, hence why after that it feels sluggish - it simply hasnt got the guts

[1ntense]

thanks for the info mate, didnt know that about peaking at 3300rpm.

so its quick lower down the rev range, therefor a 4-1 mani would probably be better for a VTR than a 4-2-1 as the former frees up more revs in the upper rev range?

so I would see much freeing up of revs with just a centre pipe and back box then?

[1ntense]

Oh yeah.. I was told by the owner that the previous owner to him had removed the silencer from the middle section?

Not sure what he meant by that?

[Ashleyp]

thanks for the info mate, didnt know that about peaking at 3300rpm.

so its quick lower down the rev range, therefor a 4-1 mani would probably be better for a VTR than a 4-2-1 as the former frees up more revs in the upper rev range?

so I would see much freeing up of revs with just a centre pipe and back box then?

a 4-1 mani wont improve it massivly

vtr's lose all grunt towards the top of their rev range

unless your spending a lot on new camshafts to raise the power band, then you'll never see much gain

removing a silencer will just make it louder

[1ntense]

it is pretty loud, not that keen on it tbh

I take it a supersprint centre pipe wouldnt make it any quieter, or would it?

Not sure whether I would go to the expense of cams etc as like you said, I would probably just be better planting a VTS engine in it.

could you explain what throttle bodies are/do please?

[Ashleyp]

as per other thread of yours, if your not going to declare your mod's id leave it standard

[1ntense]

I suppose it makes sense to declare them.

I just feel that insurance companies are mugging us off that much as it is, plus the fact that Im 3rd party fire n theft, so if I smash it they wont pay me a penny, then if I modify the engine, which a theif or arsonist wouldnt know about anyway, they want to charge me more money.

Im more sensible in my old age though so probably would declare to keep things legal etc

[Ashleyp]

I suppose it makes sense to declare them.

I just feel that insurance companies are mugging us off that much as it is, plus the fact that Im 3rd party fire n theft, so if I smash it they wont pay me a penny, then if I modify the engine, which a theif or arsonist wouldnt know about anyway, they want to charge me more money.

Im more sensible in my old age though so probably would declare to keep things legal etc

insurance companies arent "mugging you off" nobody forced you to buy the car you did, thats the price they charge therefore thats the price you pay

+ if your old and struggling to insure a vtr then youve got problems lol

[1ntense]

Its my opinion that they are, £980 a year for a car thats got a very small chance of getting stolen or going on fire.

You think thats a fair price?

I suppose that you think when you go in HMV and you see a blu ray or playstation game at half price that its a bargain, when it costs pennies to make and HMV themselves have probably got a 2.5% mark up on it anyway.

Look at the bigger picture my friend.

The only problem Ive got is that I was late in passing my driving test. I have now though so happy days :)

[JamesR]

a good decatted system would help

however, the 8v engine's torque peaks at 3300rpm, hence why after that it feels sluggish - it simply hasnt got the guts

So in 1st, 2nd and 3rd gear after 3300rpm it's sluggish? They fly through the gears and don't seem like they get slower to me.

[Ashleyp]

So in 1st, 2nd and 3rd gear after 3300rpm it's sluggish? They fly through the gears and don't seem like they get slower to me.

A vtr's not quick, stop dreaming

[JamesR]

A vtr's not quick, stop dreaming

Compared with? A zonda isn't quick compared with a veyron ;)

Just saying i don't think they pull any less after 3300rpm

[Ashleyp]

Its my opinion that they are, £980 a year for a car thats got a very small chance of getting stolen or going on fire.

You think thats a fair price?

I suppose that you think when you go in HMV and you see a blu ray or playstation game at half price that its a bargain, when it costs pennies to make and HMV themselves have probably got a 2.5% mark up on it anyway.

Look at the bigger picture my friend.

The only problem Ive got is that I was late in passing my driving test. I have now though so happy days :)

im sorry, but thats how businesses work

if you dont like how they operate dont buy their products.

and dont assume i dont know how they work either.

[1ntense]

Depends on your perception of quick.

Compared to what I imagine most people learn to drive in for instance, I doubt anyone could say it wasnt quick compared to that.

Compared to a Skyline/Evo/Scooby, then its not quick in comparison however.

All about perception my friend, I wouldnt class them as slow anyway.

This is a saxo forum and you're dissing saxos lol strange, Im sure you'll say oh no I love VTSs.

I agree though, they tend to pull better lower down the rev range.

[Ashleyp]

of course, im comparison to other car's a saxo can be seen as either fast or slow (depending on what you compare it to)

after owning a vtr, i can pass judgement on how they drive, especially in comparison to a vts ;)

rolling road graphs on standard 8v engines do show a decrease in torque towards the peak of the rev limit

[JamesR]

of course, im comparison to other car's a saxo can be seen as either fast or slow (depending on what you compare it to)

after owning a vtr, i can pass judgement on how they drive, especially in comparison to a vts ;)

rolling road graphs on standard 8v engines do show a decrease in torque towards the peak of the rev limit

3300rpm is no where near the rev limit :wacko:

[Ashleyp]

3300rpm is no where near the rev limit :wacko:

which is my point

after 3300 a decrease is shown.

read what youve highlighted again

[1ntense]

Ill assume what I like thanks. You seemed to assume plenty about me.

I know how businesses work, I should do, I run one lol

Insurance is something someone has to have to drive legally, its not a case of if I dont like how they operate, dont buy. Its something that is needed, they know this so can basically charge what they want.

If someone was to say ok, were going to charge you £4 a litre of water from your tap, bottled water is to rise to £5 a litre, I could say to you, if you dont like how they operate, dont buy the water.

How would you get washed though? Brush your teeth, shave? Have a cup of tea or coffee. Dont like how they operate, dont wash simple.

A better example would probably be petrol, as from tomorrow petrol rises to £3 a litre. If you dont like how they operate, dont buy. Will you walk or cycle and not drive or pay what they ask because you basically have to?

Get my point?

[JamesR]

which is my point

after 3300 a decrease is shown.

read what youve highlighted again

You said "Towards the peak of the rev limit" so about 5000rpm+ at least ?

[Ashleyp]

My point regarding your insurance was that if you cant afford to insure a certain car, then get a lesser model which you can afford to insure

[Ashleyp]

You said "Towards the peak of the rev limit" so about 5000rpm+ at least ?

I'll make it simple:

peak of vtr engines torque = 3300rpm

if thats the peak, than after that would be a decline.

5000rpm and higher is after peak, thus a decline in torque

[JamesR]

I'll make it simple:

peak of vtr engines torque = 3300rpm

if thats the peak, than after that would be a decline.

5000rpm and higher is after peak, thus a decline in torque

Sorry, i see now it's just quite late lol

I can't say i feel a drop in all honesty though.

[johnr32]

I'll make it simple:

peak of vtr engines torque = 3300rpm

if thats the peak, than after that would be a decline.

5000rpm and higher is after peak, thus a decline in torque

thanks for the info. really useful information about the powerband, no longer do i need to feel the power drop to change up;)

[Ashleyp]

Sorry, i see now it's just quite late lol

I can't say i feel a drop in all honesty though.

5th gear really shows the drop in power, once up to around 3300rpm (not sure what speed that'd be) when you try and pull the engine has no power to do it

where as in a vts it pulls fairly easily up to around 5500rpm before it begins to struggle

[johnr32]

at above^ isnt this also due to the gearing of the VTS compared to the VTR. VTR gearboxes' priorities was top end speed (even tho its still miserable) while the VTS gearboxes' where for quicker acceleration?

[Colin]

Standard stuff strangles the revs.

Like try breathing through a thin straw, its quite hard. Wider straw its much easier. Therefore bigger bore exhaust etc the gases escape easier and rev better.

[Cammy]

This kinda helps me in a fair bit to see my car in a way.

Because i compared the size of the milltek bore to the Supersprint bore - and its a huge difference as the milltek is a somewhat bigger bore, but last time i had a breather filter on - the oil pissed out of the breather filter which i dont understand why it should have..

But the only problem with Cam's is that they are very hard to get installed arent they?

from what ive read, youll obvously need all the gaskets, a new timing belt and pulley, obviously the new cam, waterpump etc etc, and obviously an new ECU (i.e omex 600) which can run up to about £1000 of fitting of all that, without mapping it, and mapping at about £300 more?

Its allot of money, for about what 10 bhp? but then again its a noiticeable gain once all the breathing mods and exhaust mods are done.

[Saaamon]

Its my opinion that they are, £980 a year for a car thats got a very small chance of getting stolen or going on fire.

Its not about the chances of it catching fire or being stolen its about your driving abilty and your attuidue towards it.