Rolling Road Results

WORD !!!!

Exactamundo....

yes at 1 bar 43 bhp but you wouldn't expect to see much increase without increasing the boost - all the mods to my car over and above the standard engine are turbo related to be let me run higher than stock boost. its not ever going to be much different to de-catted A610 on the same boost setting

Hard evidence of the 285bhp brick wall on the manifolds though...

Where? The figure of 232kW, or 312hp is on the plot in black and white (well blue actually...) I'll scan it in as soon as I've found out how to use this bloody scanner.....

But here're some snaps to get you in the mood



And to keep the bigger on the rollers in 4th required two fat blokes

Aiiiiiiiiiii .........Fat Blokes , joggy bottoms,less drag ,more Colin Jackson

Hard evidence of the 285bhp brick wall on the manifolds though...

Where?

The law of dimishing returns, and all the other PRV V6's running those manifolds..

I seem to recall you going on record saying that you can't flow enough exhaust through those manifolds to generate more than 285hp regardless of boost..... well it's been done now.

And pressure and flow are directly proportional so double the pressure, double the flow for a given bore. You're correct in a naturally asp engine where the pressure is constant so doubling the bore area will double the flow you can "suck" through it. (I do have quite a bit of hyraulics experience BTW)

But there is a law of diminishing returns as you say because the more restrictive it is, the more energy you rob just trying to push the gas through it at higher and higher velocities.

Both Chris ar MPH and Mike at Cyclone pulled a face at the size of the throttle, and I personally think the tight bends on the intercooler don't help either, based on the opinions of skyline tuners on tight bends in intake pipework - not had much experience myself of this

I seem to recall you going on record saying that you can't flow enough exhaust through those manifolds to generate more than 285hp regardless of boost..... well it's been done now.

No, not regardless of boost, the europa Cup cars ran 300bhp.

hi tony

quote

Set up for 1.2 bar where it produced 232kw at 5056 rpm and 476 Nm of torque - or as I prefer 312 bhp and 351 ft/lbs.

was very impressive tony shame about the hose coming off
i,m sure anyone that gets the oppertunity to go in it will also be

[stephendell]

Was all that heat generated during the 1 bar or 1.2 bar power run?

Those manifolds are seriously hot Time to get some heatshields back on!

The studs in the head must be under some serious stress too!

Isn't a cherry red glowing manifold a good indication of air restriction or exhaust gases that can't escape fast enough?

Could support the restrictive manifold theory

It's a shame the power increase wasn't more for that extra 20% boost. Probably best to stick with 1 bar and have better reliability.

Did you try any more boost out of curiosity? Would have been good to see if there was any more to come with a 60 sec 1.4 scramble...

And pressure and flow are directly proportional so double the pressure, double the flow for a given bore.

Yes, but not in the case of engines and exhausts...

Pressure is resistance to flow, so how can double the pressure mean double the flow if the pressure is building up from restriction...If I weld the exhaust completely shut you get massive pressure, don't get any flow though...

And even in the non engine world, if flow is increased we get too much through a pipe, the air speed goes to high, ie anything over 300ft per second, and we get a pressure drop..

In an engine, as the backpressure increases the VE drops, which again lowers flow...

I wrote a excel sheet on this which is used a fair bit to explain this..

www.alpinerenaulttuning.co.uk/throttle.xls

Any turbo engine running serious power will heat up its exhaust manifolds like that. All flavours of Esprit do for sure.You're making use of otherwise wasted energy, and one school of thought is to heat=-wrap the manifodls to keep the heat in so as much energy as poss gets dumped into the turbo.

I remember a friend with a Calibra turbo told me he'd seen it so hot the turbine blades could be seen through the casting.

I wouldn't worry too much about the manifold studs, they're only 66p each from Renault

There's a definite ceiling at 320 though -- the graph made that obvious. I'll bet Dave a sensible amount of money (say enough for a couple of beers ) that a larger throttle will shift that ceiling.

Still working on this bloody scanner

There's a definite ceiling at 320 though -- the graph made that obvious. I'll bet Dave a sensible amount of money (say enough for a couple of beers ) that a larger throttle will shift that ceiling.

Still working on this bloody scanner

A610 with 11psi and 55 mm throttle body = 250bhp

Saf Biturbo and only 7psi and 55 mm throttle body = 268bhp

A610 Biturbo at 13psi and 55mm throttle body = 430bhp

Sorry it got a little crumpled, I think Rob sat on it

What boost is that because I make it 297bhp (non corrected)