Wallaby Joe

Hey guys ........ I have a 92 Turbo which I put on a dyno yesterday after installing a 'turbonetic', turbo.

Question is - the horsepower figures as stated by the factory for our vehicles; is that at the rear wheels or the fly wheel ???

I will tell you the reason for me asking this question when I know the answer.

Thanks

Gav.

MeanMachine

Flywheel

Wallaby Joe

Hey MeanMachine ..... thanks for that.

On the dyno the car was only producing 182 Kw or 244 Hp at the wheels, which I thought was well down on factory spec's. My belief was that porsche always measured there horsepower at the wheels.

I still have a way to go in tuning it. Figures show I am running very rich at 2570 rpm and continues to drop until reaching 3600 rpm then it begins to lean out at 5430 rpm.

My goal is to achieve 400 Hp at the flywheel without any other modifications, but for an adjustable warm up regulator. I was told the turbonetic's turbo would give me an extra 80 Hp. Not sure how true this is but I do notice a different in the performance of the car.

Can anyone suggest a brand and supplier for the adjustable wur. If anyone has done the adjustable WUR modification is it a straight bolt on job ??

MeanMachine

I wouldn't install any turbo except KKK Borg Warner. For Adjustable WUR, contact Brian Leask he is over at Pelican Parts forum. If you want to achieve more power, look at headers and exhaust.

Metal Guru

All OEM's measure torque/hp at the flywheel.
The 965 was advertized at 320 hp.
I would suggest that your wur is shot. An overly rich mixture will limit hp. You also might have a boost leak.
An adjustable wur will let you get the enrichment correct for your increased mass flow. It is bolt -on but you will need tools and great patience to tune it (CIS gauge and an LM-1 or LM-2). Brian Leask can make your wur adjustable www.930wur.com
You won't get to 400 whp with just bolt-ons. You will need cams, fuel distributor work and possibly head work to achieve 400 whp with CIS, not to mention a clutch that's got more clamping power than the stock one.
If you wrench on cars, all this is do-able. If you don't I suggest you either leave the car as stock, spend your kids college money to have a tuner mod your car (choose your tuner carefully) or buy a newer Turbo that has more stock hp. This goal will be expensive in any event.

carmstrongls1

Turbokraft in Arizona has good results with these cars. Not cheap though.

Wallaby Joe

I do all the work on my car myself. Have been working on Porsche cars (only 911) now for about 15 years. Not a mechanic but love restoring them. Everything on this current car I have done myself, from oil system rebuild (every hose and bit you can think of without splitting the engine), Brake system, suspension, aircon system, fuel system (including pulling down completely CIS and rebuilding it). Most difficult job I did was removing the right hand side chain box to replace the seal behind it (engine still in car). All work has been done in my garage using floor jacks. Next project is building a garage and investing in a hoist. Lucky I don't have kids.

Thinking about what you have said Metal Guru, it maybe more a boost leak then a wur. When I first bolted everything up the car run really strong. Now after some hard running it seems doughy on boost like it is leaking, though it still pulls.

The wur I had checked out by a specialist here in Australia, who said it was working fine but running slightly on the rich side. However I will be in touch with Brian Leask.

Anyone want to guess what horsepower the car is producing at flywheel if it is producing 244 Hp at the wheels.

Thanks guys for your input.

carmstrongls1

That's about 280. Apparently our cars don't suffer more than about 12-15% drivetrain loss.

MeanMachine

280hp on x.15 drivetrain loss.

Frank 993 C4S

+1

Don't start with the turbo, suggest you start with headers and exhaust and boost spring and then work yourself up from there.

ralt

agree with Frank993c4s. You can get more hp by doing the headers, cat by pass and 1 bar boost spring. If you want 'around' 400 whp you will need an engine rebuild done really well. A little compression boost. dont need cams but since its apart its just more money. I have those items, full engine rebuild, no new cams, higher compression, 1 bar spring= 383 whp and 393tqs= 100,000 miles. The more you boost the motor the shorter it will live. Unless you have the 30k plus for efi an engine rebuild by someone who knows what he is doing, stick with CIS and enjoy it.

Metal Guru

Agreed, headers and a high flow muffler is the starting point. I shouldn't assume everyone knows that.
There's some trade-offs on how to get more hp. You will pick different paths depending on application.
Raising the compression ratio limits how much boost you can ultimately run but it's good for off-boost torque. There's other ways around raising the compression ratio to improve low speed torque. Swapping in SC cams with more duration provides a nice flat torque curve, which is fun for the street. A lightweight flywheel gets you through the dead spot quicker and accelerates faster in the low gears.
For some 400 whp is the holy grail. It's gets really expensive to approach that figure. Like Ralt, I have put together a fun engine that comes in somewhat close to that power level. I have headers, SC cams, a hybrid K29 turbo, a FVD ignition advance bracket, a lightweight flywheel and a Leask wur. I run at .9 bar. The engine is somewhat conservative but has good performance everywhere in the spectrum and it's not a cantankerous grenade.
A rebuild in and of itself will not increase hp on an otherwise healthy engine but gets done if you are making major changes (new pistons, head porting, ect.)

ralt

Adding to Mertal Guru, suggest doing as much bolt-on stuff as you can first ie. headers cat bypass, light flywheel, BECAUSE....once you open the engine for work, your costs really go up with the required hours of work and expertise of the engine builder.

Steven C.

I have busted 400 to 420hp with cams, Turbokraft port and polish on the heads and intake, we poly coated most internal engine parts, FVD advance, free flow cat, Strosek muffler and a few other little things. Still running CIS and stock new clutch which is plenty, no slip. My turbo and WUR may have had something done to it in the past but once we put the motor back in and ran it, there was no need to get into it. They look stock. Runs like a scalded cat and the RUF guys claim its as fast as they have seen, even the moded ones that come through.

Light flywheel adds no power and just makes the car stall easier in traffic or reverse, been there done that. No header needed. Next year I can remove the cat completely as at 25 years in Texas no more emissions testing....Yea!

Have fun!

Metal Guru

Steve, correct about no power added, but what is does is reduce parasitic inertial loss, which you feel in 1st and 2nd gears. On my car, I'd say the SC cams added one level of performance and the lightweight flywheel added yet another level in how the car behaves when not on boost. When I first got the car running I still had the dual mass flywheel so I pretty much experienced the difference back-to-back.
I have a Sachs GT2 pressure plate, which has a somewhat heavy action, but I've not had any issue with stalling my car. Now maybe if I lived in the hill country around Austin I'd have a different opinion but Detroit is flat so no worries.
If you were at 400 hp at the wheels, you would need headers and a much stronger clutch set-up in addition to your mods to get there. You should consider headers when you ditch your cat. It will really wake your car up.