RAOC Proving Day 2 - Confirmed 30/11/07

300 may be a bit ambitious but I reckon 260 is within the grasp of mortal men . Then there's always the weight loss route if you're serious about it
I'm pretty certain I have 220 at the minute with the new turbo and old management running too big an injector ......................It's been on 3 different types of power devices and they all agree .

So how much will the Adaptonic add when it is mapped properly ? ( I reckon I have a trigger issue )Got to be 20/30 I would hope .

300 may be a bit ambitious but I reckon 260 is within the grasp of mortal men . Then there's always the weight loss route if you're serious about it
I'm pretty certain I have 220 at the minute with the new turbo and old management running too big an injector ......................It's been on 3 different types of power devices and they all agree .

So how much will the Adaptonic add when it is mapped properly ? ( I reckon I have a trigger issue )Got to be 20/30 I would hope .

On its own it won't add anything, ie on a standard car at standard boost it probably won't make any topend gains (midrange will be improved). Standalone only gains when you change the original spec/boost and this allows you to 'manage' those modifications properly.

I'm with Monkey on this one It should remain a PRV worst case scenario but getting the best out of the std lump is what I want to do

300 bhp or near should be obtainable once you get round the crappy mainfolds senario can it be that difficult if 360 from the 24 valver is possible then 300 should not be a prob from the 12 valver ?

Si21

You can nearly hit 300 with the original manifolds, just not quite.

12v 3.0 with twin turbo's (specced correctly) should do around 360.

Well yes I'll up the boooooooost innit
What I mean is ,the car at the mo is not making the best of it's mods .Bigger fueling and turbo + it's still in Renault std ecu mode apart from the boost cutout .

Surely a car with lower gearing will cover 1/4 mile quicker than one with higher gearing. Take two identical A610's for example, one with a standard, one with a 3.88:1 final drive. I know which one will cross the line first, but I also know they both as powerful as each other.

No, if it was that simple, everyone doing drag racing would simply fit smaller diameter wheels on their cars...

Well yes I'll up the boooooooost innit
What I mean is ,the car at the mo is not making the best of it's mods .Bigger fueling and turbo + it's still in Renault std ecu mode apart from the boost cutout .

Ah, yes then.

I know I'm doing it slowly but it does show just how much ' bang-4-bucks ' you get

No, if it was that simple, everyone doing drag racing would simply fit smaller diameter wheels on their cars...

So I'm wrong then?

I have driven a DeLorean with a 3.8 final and it's decidedly quicker off the line. Physics would suggest that as long as you do the same number of gearchanges, the one with "smaller rear wheels" will have an advantage

You're always wrong .............................accept it and move on

Well yes I'll up the boooooooost innit
What I mean is ,the car at the mo is not making the best of it's mods .Bigger fueling and turbo + it's still in Renault std ecu mode apart from the boost cutout .

...........................Mmmmmmmm Tony smith melted his manifolds running around 300BHP on a T4 so under bonnet temps would have dropped a little one would have to assume, I saw your turbo and manifold almost transparent LOL why do you think it will handle much more boost LOLOLOL without melting

Why do people not carry out conventional modifications on these engines a bit of porting and and a couple of cams, This makes the engine more efficient and will give more power for less boost which keeps engine temps down. You may lose a little bottom end but the results in mid and top end would be worth it.

I beleive I heard there are a set of cams for the turbo lump that I beleive live in the front of a Renault 21 Turbo Quadra (It was a R25 lump)

So whats available?

Cams they are only bumps on sticks I beleive the 3.0 N/A with engine mods has produced 340 Bhp

So why cant a turbo charged 2.5 I realise the firing pattern is different and the cam profile may be different to suit turbo charging but hey like I said bumps on sticks, different sticks and different bumps

si21

You don't want to believe everything I say Si

The boost is at 15 peaking at 18 and won't be going any higher .......................

Innit tho .......................



I sold DG a set of 2.8 25 cams that I think are the ones you mean but I've got another spare set to get reprofiled .

Well yes I'll up the boooooooost innit
What I mean is ,the car at the mo is not making the best of it's mods .Bigger fueling and turbo + it's still in Renault std ecu mode apart from the boost cutout .

...........................Mmmmmmmm Tony smith melted his manifolds running around 300BHP on a T4 so under bonnet temps would have dropped a little one would have to assume, I saw your turbo and manifold almost transparent LOL why do you think it will handle much more boost LOLOLOL without melting

Why do people not carry out conventional modifications on these engines a bit of porting and and a couple of cams, This makes the engine more efficient and will give more power for less boost which keeps engine temps down. You may lose a little bottom end but the results in mid and top end would be worth it.

I beleive I heard there are a set of cams for the turbo lump that I beleive live in the front of a Renault 21 Turbo Quadra (It was a R25 lump)

So whats available?

Cams they are only bumps on sticks I beleive the 3.0 N/A with engine mods has produced 340 Bhp

So why cant a turbo charged 2.5 I realise the firing pattern is different and the cam profile may be different to suit turbo charging but hey like I said bumps on sticks, different sticks and different bumps

si21

Because of the manifolds..

Look, the PRV's have 40mm inlet ports, general rule is that will not flow more than 250bhp normally aspirated. Engine CC has nothing to do with power, just revs and valve flow, but the ports on these engines are smaller than the valves etc. 330bhp was the max ever acheived on the PRV, but this is on race fuel, 8000rpm, sliding throttlebodies, 300+ degree cams with completely reworked heads, valves, ports etc. The true epitomy of taking the engine to the max, but by no means a usable road car engine, simply race.

Simon, with the standard manifolds, doing cams, porting doesnt make a blind bit of difference, hence why everybody hits 285bhp limit no matter the engine, whether it be the 2,5, the 2,8 or the 3.0 which does have better valves and slightly bigger ports. The exhaust side is simply too choked up at the engine will simply not flow any more air.

So you then think, ah, sort out the manifolds etc...Good idea, but now the lag is so much worse that you are coming on boost at say 4500, and the engine will still only rev to 6000 max (maybe lower) as this is all the engine will rev to naturally aspirated.... and having a turbo in the way of the exhaust system still creates more pumping losses than no turbo at all so all you have is a car with a narrower power band, and still doesn't 'rev'...

So you have to spend a shed load going biturbo, and then only to limit the power so the next weakest link (the gearbox) doesnt die...

Cams they are only bumps on sticks I beleive the 3.0 N/A with engine mods has produced 340 Bhp

So why cant a turbo charged 2.5 I realise the firing pattern is different and the cam profile may be different to suit turbo charging but hey like I said bumps on sticks, different sticks and different bumps

si21

Cams are only bumps on sticks, but if you have opened the valve so far that it is no longer a restriction and the port is, then putting a bigger lump on the stick is not going to make any difference - and because this is a primative engine long duration high lift cams will make it run like a pig.

Take the 21 Superpro, it made 480bhp but it took 316 degree cams with 12mm of lift and 35psi of boost to do so...

A modern 2.0 16v can do that kind of power with 260/270 degree cams with around 25psi.

No, if it was that simple, everyone doing drag racing would simply fit smaller diameter wheels on their cars...

So I'm wrong then?

I have driven a DeLorean with a 3.8 final and it's decidedly quicker off the line. Physics would suggest that as long as you do the same number of gearchanges, the one with "smaller rear wheels" will have an advantage

Martin, the one with smaller wheels won't have travelled as far either...

And here are all these top fuel dragsters, with these massive diameter rear wheels, fighting for hundreths of seconds between them, and all they had to do was fit smaller rear wheels...

I've seen them-there Rails ........................wheels start off all short and fat but then go all tall and skinny Was all dat about den