3.9 RSR project --- my Carrera reborn

[911teo]

It was me... Silver black stripes? thank you!

[barney911rs]

Jeff,

I think the main reason for running the brake cooling hoses in the trunk is there is more room. I'm looking to do something very similar in my car. Although no where near this elegant.

I think we can all agree the best air comes from the front of the car rather then a-arm scoops. I know on my car there is not enough room in the wheel well with the tires I have to run a hose back to the caliper from the front. If the hose comes out of the trunk into the wheel well, it will be in the center near the strut, away from the edges of the wheel and tire.

I don't think they are just going to dump the air into the wheel well without a hose directly to the caliper. Keith, If I'm way off base here, go ahead and correct me.

[eimkeith]

oops, I've missed the past few posts...

Jeff and John: we discussed cooling the brakes with the leftover air from the cooler (since hot brakes are going to exceed the temperature of the air coming off of the cooler significantly), but didn't duct down to the rotors for the fear of reducing the volume and velocity of exit-air. - At some point, air would rather flow around the front of the car, rather than through the cooler - I don't want to reduce the volume and velocity on the rear side of the cooler by choking it down to the caliper and blocking it somewhat with the rotor.

Will there be any additional benefit to dumping oil-cooler air into the wheelhouse in regards to the brakes? I really don't know. Running hoses through the trunk to keep from ripping those !@#$%! hoses off with wider than oil-tanker tires is a really great idea, if just for the sake of anger-mangement, lol.

Unfortunately, we are now out of real estate in the ol' boot, as they say.

[Elombard]

Yes indeed I would be happy to ferry any of the cars (except the Cayenne) from Charlotte to the port...and get myself back :-)

[Jeff Alton]

Keith, thanks. I think I will do something similar.....

Cheers

[911pcars]

Ambient air temp would be vastly cooler than air temp exiting the oil cooler. Can't beat that. The highest air pressure is at the middle of the front end. Thus, it sounds like oil cooler and brakes share the somewhat same real estate for air. I think each can receive ambient air.

Trunk-routed brake ducts are the best solution for a track vehicle. I can understand the reluctance to cut up the trunk on a street car.

Sherwood

[Jeff Alton]

If you don't have a fuel cell, it is pretty tought to get the hoses into the fender well in a good spot....

Cheers

[911teo]

We'll have dedicated brake cooling ducts that go from the front IROC bumper to a disc plate for brake cooling.

The fact that the air that goes throught the oil radiator also ends up in the wheel well might have the side advantage of reducing the disc temperature, but that was not the reason for the in-trunk ducts.

We wanted to maximise the airflow through the front oil cooler but I was not prepared to cut a hole in the hood.

We thought the RSR solution of the slanted front panl was not the best as it allowed air under the car, creating lift.

We thought that by creating big enough ducts we'd acheive the same airflow withouth the negative aerodynamic losses.

If it cools the brakes as well...

[911pcars]

Didn't 935s or Kremers have louvers in the front fenders and a low pressure section (body notch) created by the extended front fender/wheel well? Could it have been to help evacuate air from brake and oil cooler and air that managed to get past the front air dam? That is, besides a fender to house the huge front wheels/tires.

Sherwood

[Mothy]

Matteo

Quote - "We'll have dedicated brake cooling ducts that go from the front IROC bumper to a disc plate for brake cooling."

Are you expecting any problems finding a straight enough path for the hose doing this - I seem to remember than there have been a couple of threads dealing with air's dislike for turning corners and working your way around or through (split pipe) the A arms to stop the pipes being crushed on full lock.

I'm about to do the same for my street SC - front IROC to backing plates and would be intested is seeing how you do it.

Tim

ps - love the car and the thread - great read

[Duckworth]

.....curious about the idea :

Since we hear that the motor sits in queue, and the fine tuning wont be seen by us here - couldn't we still converse on various expected and/or 'unforeseen' stuff on tap ? ?

Just wondering, what the pluses and minuses may be of this particular powerplant..... ?

Excellence has written before of these conversions -
that the bigger motors, while having more torque on tap - don't have the extraordinary reving 'feel' of the early 2.7rs for example....

....thinkin' it would be great if this thread could continue to inform - on the motor-assembly part of the conversion.



______________

[911teo]

Obviously there is more mass but we tried to keep everything lightweight with the new materials (Ti etc).

I believe the most delicate and important choice for these motors is the cams.

They will be the single most important factor that determines the personality of the engine.

And until it is driven it's difficult to really predict what it will feel like.

The idea was to push the limit as high as we could mantaining a decent idle. The fact that the Motec ECU is very flexible gave us a little more confidence.

So the cams are DC-62. The sweet spot should be at 7,400-7,500 rpms. Will it get there as fast as a 2.7? Nope, but it should be comparable to a 3.8 RSR from that point of view.

I'd love for people with more engine experience to chime in.

Anyway.. latest update is.... motor is running nicely. Cold starts are being performed as I type and the motor will be ready ither tonight or Wednesday.

Numbers soon.

[herman maire]

cooool....

try to get some quicktime video clips of the motor

[mjshira]

Originally posted by 911teo
Obviously there is more mass but we tried to keep everything lightweight with the new materials (Ti etc).

I believe the most delicate and important choice for these motors is the cams.

They will be the single most important factor that determines the personality of the engine.

And until it is driven it's difficult to really predict what it will feel like.

The idea was to push the limit as high as we could mantaining a decent idle. The fact that the Motec ECU is very flexible gave us a little more confidence.

So the cams are DC-62. The sweet spot should be at 7,400-7,500 rpms. Will it get there as fast as a 2.7? Nope, but it should be comparable to a 3.8 RSR from that point of view.

I'd love for people with more engine experience to chime in.

Anyway.. latest update is.... motor is running nicely. Cold starts are being performed as I type and the motor will be ready ither tonight or Wednesday.

Numbers soon.

great news!!! there MUST be a sound file posted...

[jevvy]

Originally posted by 911teo

Anyway.. latest update is.... motor is running nicely. Cold starts are being performed as I type and the motor will be ready ither tonight or Wednesday.

Numbers soon.

You must be extracited - I hope it all goes well and look forward to the next installment.

[Jon Merck]

Great news Matteo! So we will get to see her at Lowe's on Sunday?

[911teo]

Originally posted by Jon Merck
Great news Matteo! So we will get to see her at Lowe's on Sunday?

I wish...

No things are never as easy as they could be.

We are working on the logistics of shipping the motor over here.

There is no chance the car can be at Lowes...
Even if it was finished today (do u really believe it?) at the earliest the motor willbe here on Wednesday. Then there is all the plumbing etc...

Video and sound files in due time.. sorry but not a priority right now...

[911teo]

The motor has been tuned.

It will be here on Monday.

I just got off the phone with Timmins.

Timmins spoke to Peter Dawe and he's very very happy with the results and especially with the torque.

I have 1 number only, waiting for the dyno sheets and other details...

It is putting down 310 rwhp. At the wheels. I don't know what dyno etc. So obviously not a very telling piece of data.

I always wanted to dyno the GT and the 911 together for a comparison but the GT is leaving for London this Saturday...

More details soon.

[kaisen]

Good news, but sad that you and the car are leaving so soon

[Duckworth]

Video and sound files in due time.. sorry but not a priority right now...

Understandable...


--------> 310 r.w.h.p. <----------



_______________