360 N-GT tuned to 540HP!!? How?

I agree. But to add, my "old" 911s (plural, not 911S) were never giant killers. But for me it was more about the connection, the driver inputs, the quality in engineering, and as I've previously mentioned, the usable HP and torque for the street. I love my 360. I've driven a 458. Frankly I feel more connected and in control with the 360. The 458 has the HP yes, but if feels a bit too sanitized to me-- but the looks of course are a true grand slam to be sure!

As I've gotten older and can afford more than one nice car I've found that a fussy, high maintenance ( and usually unreliable is part of the mix) ride is more of a drain on my fun meter than I want.
I'm not against mods at all and I have modified rides for sure. I just like driving my hot cars more than working on them. Maybe it's an age thing. But driving a totally radical, twitchy, and incredibly noisy car on the street that you cannot wait to get out of after 20 minutes has lost it's charm for me.

Apologies for the rambling...

 

Correct, my error. But the owner of a Challenge car didn't think it has 400 hp and put it that way in an advertisement to sell the car. Particularly if they had done a lot of mods to the car that are all called out. That is the essence of my point.

 

perhaps they stuck a basic 400hp modena engine in the race car after the motor failed...... and to make it street friendly?

 

Ferrari lists the 360 challenge as having the same hp as the modena the challenge stradale has more hp Image Unavailable, Please Login Image Unavailable, Please Login

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Must have been an absolute blast! Thanks for sharing! If you have any "leftover" ECU tunes laying around it would be awesome to play around with

 

For what it's worth, Porsche stated their 996 and 997 Cup cars made the same horsepower as the equivalent GT3 street cars. They didn't
With regards to the first and second generation 997 Cup cars, Porsche quoted 400 for the first (they actually made 420) and they quoted 425 for the second (they actually produced 445)

I suspect Ferrari were no different, so it's very possible those Challenge cars made the same HP as the Challenge Stradale street cars ...

 

Only just saw this thread..

Let me just start with some observations.

Most 360's came from the factory with the stock heavy 'coffin' muffler. That alone means most cars actually on ran 380hp or less from the factory gate and that was for an EU spec car or MY 1999, 2000 US spec car (the ones without the header cats). If you had a later 2001 spec car with the full smog compliance that Ferrari where forced to fit you got heavier more restrictive main cats and a set of header cats too which sapped the 380hp even more. More like 365hp out of the gate and these day with incorrectly setup valve timing (still deemed 'within' tolerance) and perhaps laggy fuel injectors, weak coil packs and old slow reacting primary o2 sensors and tired air flow meters that figure could be as low as 330 to 340hp. Yikes, no wonder some people think the 360 is 'under powered' when they first drive some examples. The very first thing therefore to do is ensure your example is in perfect tip top condition which means swapping out all those old 'maintenance' parts like primary o2's, coil packs, plugs, air flow meters, etc.

A useless factoid of the day is this, the fastest factory Ferari 360 cars ever made where ones destined for the GULF (UAE) states with the optional sports exhaust. Why? Well those cars (super rare these days!) actually ran 360 Challenge Cats (i.e. cats that where ' hollow ' without any cat cores!) so they literally ran factory de-cat pipes (!), no header cats and had all the emissions validation coded out in the ecu's so they where basically same spec engine wise as a 360 Challenge. Lol, seriously, This is true, no joke! These cars ran around 425hp out of the factory gate and screamed like you can imagine.

With the optional low back pressure sports muffler (also known these days as the "Challenge Stradale" system) some of the early cars made the full quoted ticket of 400hp but even then that was on the "Pristine examples" with perfectly dialed in factory cam timing and best of the balanced engine examples. Very few of them are like that today I suspect unless they are really well maintained and by companies like AV Engineering who use dial guages to ensure absolutely perfect cam timing.

For example up to 5% variance in peak power was deemed as 'acceptable' during engine build room and dyno testing when they where new. In fact this actually translated to significant variance in the weight of rotating masses. For example the Pankel titanum conrods and even the pistons. Actually all engines built got them balanced in terms of having matched sets but some sets where better than others. Due to manufacturing tolerances some sets where lighter than others. How much? Well for example there was 7 different classification bands and the best examples (Class A) had a weight of 380g per connecting rod. If you where unlucky you where in the worst class (Class G) which meant your conrods had a weight of 408g each. That's at 28g difference PER connecting rod meaning your entire rotating mass was up to 224g heavier on a car per engine basis. Doesn't sound like a lot until you realize that lot is rotating at over 8,600 times per second at high rpm. And that's before we even talk about pistons which also had similar classifications. Ofcourse the Challenge car engine had better tolerances and they used 0.5% balancing which equated to best lowest weight matched sets so the difference in power was minimal between cars. N-GT's where totally bespoke hand built engines by Michelotto so cannot even be compared. Totally different gravy!

When I've been fettling cars with AV Engineering in the past few years the best example was a car that had poor cam timing and needed some maintenance due to bad coils. That car was running around 330 hp when it came in and felt very sluggish indeed. After all the faults where rectified, sports cats fitted and a rare factory sports system fitted along with a full remap to Challenge Stradale Stage 2 spec the car was running over 100hp more than when it came in! That's an extreme case but just goes to show how sensitive these cars are to proper maintenance and choice of spec.

If you want to go beyond around 430-440hp on a 360 you will very quickly hit duty cycle issues on the fuel injectors (maxed out basically) and already they run 3.6 bar fuel pressure (vs 3.0 bar on stock Bosch Applications) so are already over pressured. You could probably stretch this out to 4.0 bar safely with re-calibration but really the best way is to upgrade to larger fuel injectors and re-calibration.

 

360- any way to extract 500hp NA from the 360 w no budget concerns::

inc c/r with race gas?
Larger bore and or stroke?
More aggressive cams lift / timing?

I have dreams of picking up one of the readily available 360 engines…. To modify and swap into my car… and tuck the orig mill away.

 

Great info and interesting about the injector duty cycle . At one stage you spoke of building a higher output engine with info from a race team . Have you got any further with this ? One of the mods mentioned was the inlet manifold spacer between the head and the manifold , off hand I cant remember the thickness . This increases the inlet track length ( very little ) and if made from a Teflon type material would also create a heat barrier reducing the heat transfer to the inlet manifold .
I think you have a race spec flywheel installed ? There was also talk of an Enzo type plenum chamber to help equalizes the flow front to back ( throttle bodies on the sides not at the rear ). I think Ferrari did change the shape of the plenum chamber to improve this .
There was also talk of a throttle body mod ( flow improvement ) as after all the CS upgrades this is the next flow restrictor . Do you have any more info on this and other tricks ?

On a side note about weight and balancing . I installed 355 Titanium rods ( almost the same as a 360 rod just the rod bolts use a different method for cap alignment) in my 308.
Had custom pistons made to accommodate the larger gudgeon pins and upped the compression ratio . The weight I lost using the Ti rods made such a difference to the performance of a (apart from the compression ratio ) pretty much standard engine . Everything was weighed and balanced and it has made such a sweet engine that just loves to rev .

I have a spare 360 engine that I want to strip and blue print and am looking for all those little details/tricks that end up making a sweet engine .

 

Based on your initial question, and then the additional "?s" regarding c/r, bore, stroke & cams, then the question that I would really ask of you is: "How long do you want it to last?" Sure, it may be possible to achieve 500hp NA (depending on where you're measuring from), but will it be enough to complete that task only long enough for the dyno run? Or for a track season? Building it to produce 500hp and being able to take advantage of that power for an extended period of time without a dedicated team (and accountant) could be a tough balancing act. And everyone will probably have a different end goal. I'd love to have 500hp also! And I also asked similar questions as you. The answers that I received all revolved around the perceived longevity of such a build. If you decide to give it a go, and the engineering makes sense, then I'm sure that there may be others would be willing to make it worth a machine shop's time to produce a few more components in quantity. But then comes the next part... What is the next part to break, or rather becomes the weakest link after that? Transmission gears/shaft? Axle shafts? Frame rigidity? I definitely don't have any data or answers for those questions but I will listen carefully to those who do. Don't get me wrong, I'm not saying to erase the notion from your mind or to stop dreaming about it. On the contrary, I'd like to know how the dream really ends! Hopefully with a very big smile!

 

My impressions —

drive train is overbuilt
Trans and axles have shown to work on the twin turbo 360

the challenge cars achieve 25-50 add’l hp at the top of the rpm curve with more aggressive cam timing and intake and exhaust de-bottlenecking.

I think trev prob nailed the most reasonable upgrade to power by copy the challenge formula-

remove intake restrictions w tb mas and air box covers

remove ex restrictions w challenge ex and decat

then a tune to make it all work


And wgt redux for the cherry on top.


I have read of people decking the heads for more compression. But I’ve yet to see any data.

 

Ferrari told half truths... Yes it happens! I absolutely guarantee that a 360 Modena Challenge has more power than the majority of road cars.

Yes they are actually very similar to most 360's but not *exactly* the same. All the ignition timing and fueling is exactly the same as a stock 1999 Modena BUT where they differ is in the specification of emissions kit. They have NO CATS at all! No main cats (hollow) and no header cats either. They are coded out in the ecu's too.

They are basically virtually identical to a Arabian Gulf spec 1999 Modena's in terms of mapping and emissions kit. All Arabian spec Modena's of this vintage had the same specs so they ain't lying when they say its the same as a 'road car', just not one from the EU or USA....

 

The biggest challenge to gaining significantly more power are ;

Fueling
1. Fuel Pumps & fuel pressure regulator (you can go safely up to 4.0 bar from the factory 3.6 bar)
2. Fuel Injectors (duty cycle becomes a problem)

Valve Float (as you increase the rev limiter)
3. Valve Springs (float becomes a problem as you increase the rev limiter)

Intake Limits
4. Intake Red top (the intake diameter from the throttle bodies becomes a restriction to airflow)
5. Throttle bodies (you can upgrade to F430 spec ones)
6. Air Flow Meters (you can upgrade to the CS/F430 spec ones)
7. The Camshaft lobe profile...

Compression
8. Piston Compression Ratio

And finally remapping including upping the limiter so fine balancing becomes critical.

No. 7 is the most challenging to overcome in terms of cost and availability...

You could also in theory retrofit Ion sensing module from a 430 Scuderia (with appropriate ecu firmware/hardware upgrades) and its coils, plugs to get even closer to max efficiency...

Getting this done at an economically viable cost is the biggest challenge...

 

AV Engineering was mentioned above as the go to for Ferrari 360 rebuilds, is there a reputable equivalent in the US?