Thom

Oops, I hadn't noticed the second graph. Still falls down a bit then, but nevermind since as you say it's a race car that needs a wider safety margin with the tune than a dyno queen.

Regardless of how the curves look, if the engine finally "feels right", meaning all components working together in harmony, thus giving you enough confidence to drive faster then to me there is little point trying to develop it further.
In the words of that journalist who reviewed the McLaren P1 on some circuit, that he felt confident throwing around a car with nearly 1000 bhp sums up pretty well that what's important is that all components work and feel well together to give enough confidence to the driver trying things without feeling like it has to take a bull by the horns. I have upgraded my 951 always keeping this in mind and if it may not be the absolute fastest road 3L 8V around I bet it's one of the most fun to drive, and other 3L turbo folks who have driven it have felt the same.

Time to reap the rewards from your particularly long, difficult, frustrating but eventually successful march to the top!

333pg333

Thanks Thom. Very kind words. I agree too. Eeking out more power is probably redundant. I'd like to 'know' what is happening and why others can throw more advance than us into their motors but in the end we have been going along quite well and the car is stonkingly fast. I'm sure your car is extremely fulfilling to drive as it looks. Really glad you've continued to develop it to date. ;-)

Cyril

Wow, impressive work and numbers Patrick!
Great work!

reno808

GREAT job man!!

seattle951

The big car companies spend millions of dollars with CAD software developing intake manifolds. I purchased an engineering book on the topic a few years ago. They system is incredibly complex with resonance and other factors affecting airflow and turbulance. Changing the dynamics of the system alters the car's power band because of resonance effects. Depending on the nature of the pulse created, constructive or destructive interference is created. Where constructive and destructive interfence occurs depends on RPM and many other variables.

Is it possible to develop an effective intake manifold without advanced engineering experience, engineering degrees and high-end CAD-based simulation software?

Thom

Yes.

944er-teile.de

engineering by trial and error... this one was successful - or at least satisfying the builder

Chris Prack

Certainly seems that way doesn't it? Well done Patrick.

seattle951

A few years back, I purchased CAM for my 951 from a high-end vendor that rarely gets cited on rennlist. He looked at my engine specifications and his first recommendation was to dump the aftermarket intake manifold that I had purchased. He was familiar with the unit and felt that it had been improperly engineered. He recommended going back to stock or purchasing one of his units for an astronomical price (25x what my manifold cost). We spoke for about an hour and he discussed the interdependencies between cam lift, duration and overlap with manifold design. It was an interesting conversation (I have an engineering degree.) He seemed to know his stuff and was aligned to the book I mentioned.

Innovation is a wonderful thing and I am big fan of independent inventors. To me, it just seems like a very big engineering problem to solve without the support of an engineering infrastructure.

Sorry to be a wet blanket and once again, I think innovation and intitiative is great thing. I wish I had the time to do some design, fabrication and testing.

refresh951

I would suggest looking at guys like Vic Edlebrock who used basic engineering principles along with TESTING and trial and error to revolutionize the performance industry. It most certainly can be done and it is done all the time.

Chris Prack

If it is the intake I am thinking of, based on some of your comments elsewhere, it is better used as a doorstop then used on an engine. Dyno pulls back to back with it and a stock and then a barrel valve intake proved this out.

That's where I'll leave that.

seattle951

I never did get around to getting rid of my intake manifold and it is still on the car. However, in the future, I will invest in a high-end unit or go back to stock. I like a flat TQ curve and the current manifold sacrafices low and mid range TQ to increase flow for high HP. This was a bad trade-off.

I agree, doorstop.

seattle951

Computers cannot innovate, people do. (At least not yet, there is an emerging feild of study called artificial creativity.)

The value of the engineering lab is to test designs virtually before building a prototype. This allows the engineer to experiment with a large number of designs quickly and effeciently. In grad school we worked with Volvo's Trucking division on their designs for truck cabs using virtual reality and CAD technologies. (Conjoint Analysis for product design). Trial and error could achieve the same goal, but the process is expensive and time consuming.

In my opinion, the inventor/innovator provides the most value with out-of-the-box thinking. Once a new innovation is found, computer simulations can be used to test thousands of optimizations virtually before investing in a prototype.

Thom

I will be the last person on this planet to ever doubt JME's credentials, but what I can say from experience is that the LR intake is a great upgrade... when used as part of a comprehensive package that will require what its design has to offer.

seattle951

After you installed, how did your TQ change? I am sure that you gained additional TQ/HP on the top end (assumes larger than stock turbo), but what did you give up in return?

The stock manifold was designed to generate high velocity airflows at lower volumes to improve turbo spool and to reduce lag. Of course, that stregnth becomes a liability at the upper part of the TQ curve.

Note about LR. Mike and Dave are great and provide excellent customer service. It is a pleasure doing business with them and I have purchased many of their products (along with other produccts from different vendors). I may not like everything they make, but I would recommend them to anyone.