Bill the headers are really well thought and follow 9M philosophy of increasing the velocity of the flow (like their heads and ports etc).

My main concern was the noise level of the old exhaust because of the more and more stringent limits on the UK tracks.

The 9M is an elegant solution that allows me to meet the noise limits and as you can see matches perfectly the engine improving the smoothness of the torque curve.

I will take pics and a video as soon as i am back.

PS
I was able to fit the complete 9M exhaust+headers system because my oil tank was moved forward by Zuffenhaus allowing for the 993 style mufflers to fit behind the rear wheels, under the fenders...

 

Thanks Teo! That would be great. Yes, I remember that you used a 964 floor pan and oil system w/ the huge rear fenders. I was curious about how 9M did the mufflers on a 964 and 993. I know I need to keep my stock 993 mufflers w/ either cat bypass or header setup because of track noise restrictions. It's amazing to me that you can run louder pipes on a street car than a track car.

The sort of powerplant you're using is my goal.

 

There's a photo of the header installation on a 964RS in this link:

https://rennlist.com/forums/964-foru...4-headers.html

 

Thanks Colin, I'd forgotten about that one.

Again Very nice!

 

I love it, great end to a sh*ty situation

 

Not quite.




The cams are being changed next week ......

 

So Colin - any response?

 

Sorry Andrew, missed your question.


Without doubt (proven to myself over & over again on the dyno & track) in order of benefit, this is what we recommend to customers for a 964 engines to improve performance over and above the usual air filter/cat bypass/remap level:

a) Assuming that you have and intend to keep the 1991- plastic intake manifold, you will have to tune the engine to stay within a 7000rpm limit:
1. 9m Motec package (ecu, loom, injectors, intake, installation & mapping)
2. 9m Sports Camshafts, valve springs & retainers
3. 102mm (3.75 litre) pistons & cylinders
4. 9m Headers
5. Reworked & ported heads or 9m billet heads
6. Carrillo rods (for longevity, if costs permit)


b) Once you make the decision that you are happy to run throttle bodies, the plan must change to include engine mods that allow the engine to run at up to 7500-7800rpm in safety, which pretty much takes you to the oiling limit of the stock crank:
1. 9m Motec package
2. 9m ITB intake system
3. Carrillo rods (essential to change rods over 7000rpm)
4. 9m Clubsport 100 or 102mm pistons & cylinders
5. 9m Billet heads
6. 9m Sprint (similar to Matteo's) or 9m Race camshafts, valve springs & retainers
7. 9m headers
On this engine it's difficult to plan which bit to do first because the concept is to build a flexible engine where everything works in synergy, but that said if budget is going to be spit into two phases, I would definitely fit the Motec, ITB's & headers onto the stock engine, then plan a winter engine rebuild once you have collected the other parts.


Beyond this, you can add any of the following:
1. GT3 crank & oil pump (safe oiling to 8500rpm)
2. 9m Race 103mm pistons (short skirt lightweight slipper design, good for 8500)
3. 9m long rods (to match pistons to crank)
4. 9m high lift valve train -15mm lift on intake, 14mm on exhaust, adds 20hp above 9m Race cam (cams, valves, springs, retainers, followers)

My current engine also has a custom stroker crank for exactly 4.0 litre capacity, as well as having all the production items mentioned above - it posted over 65hp more than Teo's engine on the same dyno as shown in the earlier dyno graph.

Regarding the tiptronic, in all honesty I have no experience of it with respect to tuned n/a engines as all the engines we have build have had manual gearboxes on the back of them. I do know that some of my customers have supercharged their tips with success, so the box will definitely take additional torque, however I'm not sure where you would need to go to get one reprogrammed to suit a high rpm n/a engine (I know Robert Linton had his done by Porsche, but he's a bit of a special case!). Obviously plan A will be the best option with the tiptronic provided you could get the Motec communicating with it properly.

 

Thanks Colin.

So if I stick to plan a (which is obviously the best for the tip), do I have to also have to change my intake and exhaust too? Any idea of overheating in tropical climates?

Who do you work with in Singapore. I've heard of 2 or 3 993s which have your engine mods.

Best
Andrew

 

Andrew
Because you have a tiptronic with TPS sensor on the throttle body, there are no modifications at all that you need to do to the intake manifold or system to run Motec. The Motec conversion will replace the air flow meter and airbox with a cold air intake that has an air temp sensor in it, this requires minor wiring changes on the AFM plug. We also add a MAP sensor to the system, the 9m adapter loom takes care of the wiring for this. In conjunction with a new set of injectors (included) all that would then need to be done is to remap the Motec to suit local fuels and temperatures.
Assuming that you don't need heat, the header conversion is an obvious one to consider as it also saves a lot of weight, even with a standard engine it will improve response and performance, making the engine a lot more accelerative.
When you do decide to go into the engine, if the original heads are in perfect condition I would refurbish them, do a quick flow job of the ports and spend the rest of my budget on the 3.8 upgrade with Sport cams.

With respect to engine builders and tuners in Singapore, we have in the past supplied parts to individuals who have found their own shops to do the work, however I have always assisted the customer & tuner via phone & email for technical help to get their engines running optimally.