DaveK

At least between petrol stations..........

NineMeister

Actually, I doubt that I will ever try to build a 4.0 turbo engine as the concensus seems to be that holding boost into a 3.6 cylinder is a big enough problem if you want to prevent meltdown.

Some people like turbos, so they post on the turbo forums and enjoy their own company from what I have read.

DaveK

Actually, I like turbos. I know Christer is not a turbo fan - hence the way he took his car. But I actually like the kick you get when the turbo cuts in.

But then - I also enjoy my own company (more than anyone else does) - so perhaps that proves your point!

Indycam

"Brand spanking new machined from EN40B billet steel, hardened & tempered then gas nitrided to a surface depth of 0.5mm minimum. In other words good enough for F1, F3000, Indy, Touring Cars ..... "
Could you do a stock sized crank for a 964 3.6 ?

"Come, come lads, would we do this to you??"
What was I thinking ? Sorry .

NineMeister

We could certainly make one if there is a demand but to be honest your best bet would be to buy a GT3 crank and a set of our lightweight steel rods that match the smaller big end bearing diameter.

Cost is also a factor, in the UK the 964 & 993 cranks are the best part of £2500 whereas you can buy a GT3 crank for less than £2000. That said, if 5 people call me up and place an order (group buy anyone?) I will have a batch designed and manufactured.

Bill Verburg

Link to 9m post in 993 Forum

Christer

Ha ha, I like the way this is going. It is great to see the evolution and development going on at 9M - even though my car now would seem like a very 'poor cousin' indeed to compared to some of the work going on.

C H

Colin,

Just incase I win the lotto, how much money would I be looking at to get a 4.0 conversion?

Dunasso

There's NO replacement for displacement (Power throughout the band) and the torque increases to prove it.
From what I've read so far these components will aid in significant power increases and supply weight savings as well. This being stated over the additional power to weight ratio of a heat pumper. Another point to be considered here is that a Turbo has to wind up (lag time), having an almost unpredictable origin of power-on. Stayin on the power of a turbo is not all that easy and the heat typicaly generated to do so far out ways the charatoristic behavior of a normaly aspirated engine.
I'm not trying to say that a Turbo is some completely uncontrolable wild crazy ride that most people could not master; I'm conveying that when you compare the two forms the larger displacement is the more usable of the two.

Duncan

PS, adding cool air induction compressor......?

Indycam

"how much money would I be looking at to get a 4.0 conversion?"

"If JB is happy to put an extra zero on the end of his estimate I can slot his big bore rebuild in at number 4 in the list, no problem!" 02-06-2006, 05:09 PM NineMeister

So if Mr Boggiano was quoted 3k for the repair of his engine , the
4.0 conversion would be 30k , if the repair work quote is 4k , then 40k ?

20.000.00 GBP = 40,213.15 CAD or 34,886.05 USD ?
30,000.00 GBP = 60,319.73 CAD or 52,329.08 USD ?
40,000.00 GBP = 80,426.31 CAD or 69,772.11 USD ?

Red rooster

Duncan,
If ultimate power is the target then nothing comes close to forced induction !!!
As an example , think back to the 1.5 litre turbo F1 days. How does 1000 bhp from a 4 cylinder 1.5L turbo motor sound !!
The quality of driveability / response comes down to how well the turbo is matched to the motor and the accuracy of the control system.
A low pressure sytem can have a N/A feel with almost no noticeable lag, give relatively big numbers and cost a lot less than a tweaked up , 8500rpm N/A motor.
In my opinion the way to go for 400 bhp and torque to match.

All the best

Geoff

tonytaylor

I'd agree that for big power turbo is the way to go but for reliable lower power levels I'm not so sure.

I've considered using a low pressure turbo set up with a single low inertia quick spooling turbo that should give over 400hp with minimal lag. Problem is it's not exactly cheap since it would require new P&Cs, rods, fasteners, plus the turbo intercooler and ideally Motec. All of which means no change out of £15K and at the end of the day there's still the problems turbo engines are plagued with, ie lag, detonation and cylinder head gasket failure, blown turbos and other reliability issues. I've seen too many turbo cars go bang at trackdays for me to be comfortable with spending that kind of money on what could turn out to be a grenade.

I don't think 9M is suggesting the 4.0L conversion in the absence of any of his other goodies is the way forward for big hp or that the conversion alone will give 400hp. However for those who like aircooled NA engines and are not constrained by budget the cost of an engine build like this does make some sort of sense.

Red rooster

TonyTaylor,
Why P/Cs -rods -Motec ?
If the decision is made to stay low pressure and resist bigger boost, the standard pistons/heads can be modified to drop the compression back to a safe level ,especially with a twin plug motor.( Standard compression is never 11:1 )
The rods are fine, if revs stay within standard rev limit.Rod bolt strength at high revs is the problem , not beam strength at 400 bhp.

Ruf etc modify the standard Motronic for turbo conversions.

Itercooling -yes .Either air to air or air to water .

I can see where the £15k could be spent on an all out conversion but not on a 0.5bar boost-"no lag" set up.

I dont know if a tuner out there offers this kind of conversion so I will have a search.

All the best

Geoff

pcar964

If you're going to the expense of building a turbo motor, I'm afraid 400bhp isn't going to cut it.

And nobody has said anything about my idea of putting a 930 motor into a 964/993. You can get 450bhp very easily out of those motors - Why does everyone feel they need to keep their 3.6's? If you're worried about resale, I don't think the market will consider a 3.3 turbo 993 any more of a "Frankenstein" than an improvised 3.6 turbo 993. I think the 930 swap would be a lot cheaper too.

NineMeister

If you win the lotto and money is no object, the ultimate 400+bhp 4.0 litre race engine with crank/rods/p&c/heads/cams/followers/intake/motec/exhaust would cost around £30k excluding taxes & base engine.

What I can say is that IMHO there is no point in going for the 4.0 bottom end unless you were prepared to invest in a set of heads, cams and (for a 964) motec; simply because the top end parts will yield a far greater overall power and torque gain than a capacity increase alone.