curveraider

I have been following this 9m discussion for a long time and have been eagerly waiting for the California "mule". The gate seems to be the "live re-map" issue. Is the reason that this currently can not be done related to a piece of hardware that nobody in the US has... or is it specific expertise... or is it both? I have to believe with all of the techie's, especially in the Bay Area, there has to be a way to get this mission completed. Can somebody post up what is required...

kennyboy

Not sure what other's have found but my experience with owning 4 different varioram cars is Porsches power figures are as accurate or pessimistic as they always are.

e.g. my last varioram a 1996 C4S with 70k miles was putting out 285.5bhp on a reliable dyno before a remap.

Red rooster

Kennyboy,
Dont lets argue about 5bhp . We each have a view . Do we agree that 295 from a standard Vario is unlikely ?

Geoff

RallyJon

Don't get hung up on the absolute number. UK dynos add back the drivetrain and friction losses, and the numbers always seem to end up optimistic. (I know, I know, they'll defend the methodology to the end, but comparing actual output at the wheels is the American way).

Just compare before and after, and apply whatever absolute multiple makes you comfortable.

'95 993

Mad hun, I am not an engineer, so can't debate the engineering, but I can keep up with GT3's on the track in acceleration (lose out on top end - on long straights - due to red line being std not 8K ) and my car has been datalogged at 0-60 in 4.7 seconds, so 425nm kind of makes sense. Also professional race driver (porsche instructor in the UK) has driven my car and commented on the awesome torque (butt dyno) BTW he hated it in the wet on a circuit ' cause of the high torque which made it in his words too much of a handful - he loved it in the dry.

Anyway, I wanted to kep up with GT3's on the race track (in a straight line drag) and that I can now achieve, and short of a supercharger or turbo nothing else will enable you to do this. I start an intensive driver ed course on the 26th - next investment.

I will say it again, you can argue finer points over dyno figures all you want but this conversion performs on the track and on the road - this is where it matters at least to me!

Mad_Hun

Agreed, all of the impressions can't be wrong. Obviously the upgrade results in serious gains. And I have to admit I've always appreciated NA power! I'll do some more meaningful research and figure out how these heads are actually doing this.

Caveman

Mad,

If you search on 9M you will probably find some good links. Also try their website and/ or contact Colin Belton. He is a Rennlister and always happy to talk about his work.

Cheers,

David

SinVancouver

The other thing to remember that the higher numbers being seen here are after 11,000 Pounds ($22,000USD) worth of parts and work... and most likely a little more with the "while you are in there" stuff...

Red rooster

$22,000 !! My wife would be asking where this other car was !!!

Just kidding . Be really good to hear how this all works out.

Geoff

FLYT993

Isn't that about what it costs for a full rebuild (top/bottom)?

'95 993

Sinvancouver,

Spot on thats how much it cost me, plus colin fitted new rings within that price and a LSD parts charge for 2nd hand LSD but no labour charge.

But well worth it IMHO. The engine now matcheds all the suspension and brake mods I had made to the car.

Paid colin in different installments from my business so my wife didn't see a cheque for that much go out of our joint account - hope she doesn't read rennlist

Red rooster

My wife does the company books so thats a non starter ! Hmm, must find plan B !!

Geoff

SinVancouver

Yeah I am no way saying its not worth it.. at all... I have found in a lot of 9m threads I get the feeling people are thinking.. $5000USD ish for this.. something must be up.. but its pounds.. and its a lot more work/bits than people think.. not just heads. It is a serious upgrade in work and cost.. and the results are commensurate of that.

RallyJon

When you go to the UK, you see that pounds buy just about the same as dollars, 1:1. Food, wine, cars, real estate. But when you're in the US and try to order something from the UK, it's just a bit different.

NineMeister

The power & torque numbers quoted are from cars tested on our own chassis dyno installation. I have no further interest in attempting to prove the results against other chassis dynos or engine dynos, all I can say is that if I test a GT3 mk2 it makes 380-385bhp, a 997C4S (in 2wd mode) made 355bhp, a GT3RS made 408bhp, so as far as I am concerned the results we measured are realistic against factory tuned cars and hp numbers.
The 295bhp quoted for a stock 993VR was a customers car that had been remapped, it just happened to be the only varioram that I had tested on the current dyno software. Other variorams have posted between 280-290hp in the past.
As well as Chris's engine build in HK we also have a 9m 993VR engine under test in Japan on a well known tuner's Superflow engine dyno. For convenience of the tuner this engine is being run on Motec, I'm not sure of the complete specification but I can confirm that current hp numbers are in the region of 345hp which is more than his previous best measurement of a factory 993 3.8 Cup engine. If I get permission I will post his dyno graphs when the job is finalised.

It is all about volumetric efficiency of the port design. Cylinder filling is proportional to the air flow whilst at the same time proportional to the square of the intake air velocity through the port. The 9m port design simply increases velocity without sacrificing flow, giving improvements in VE across the rpm range irrespective of port length limitations.