355 Air intake Modification!

Thanks Steve, I did some searching and just ordered one (Elm). Logging IAT is the ultimate way to quantify the benefits of heat shielding, etc.

Also found a very cool IPhone app that can read the output from an OBDII wifi sender unit, but the whole setup will run over $200...and it wasn't clear if I could get that data over into excel to graph, etc.

 

I use the ElmScan with the Bluetooth adapter so I don't need to be tethered to the car. I haven't used it lately as my old laptop died and I haven't reinstalled it on my new one yet. Setting up the graph ranges is a little goofey(not very intuitive) but overall works well. Let me know how it goes for you.

 

Jay, I never noticed in your engine-out thread a couple of years back that you re-routed the air intake ducts back to the C pillar location of the original design. I for one never figured out why the ducts were ever moved. Obviously in the spider this design change made sense, but I find it amusing that the new 458 has adopted a similar ram-air intake to the original 355 design, right down to the C-pillar location. Must have been something right about the original design! Anyway, Jay, how exactly did you re-locate the ducting to the C-pillars? Any cutting required, or do the block-offs just punch out? Would love to see any pics you still have. Finally, have you noticed an increase in hp, or at least a more stable running condition since the mod? Sounds like you have in fact measured intake temps and seen a real drop in intake temps. I recall Goth putting a divider in his wheelwell at or around the intake hose to reduce the intake of radiator-heated air, and that he noticed a more stable idle as the fans cycle on/off. Seems like your mod to revert to the original design would accomplish this as well. Sorry for the thread hijack guys, just a topic I occasionally think about.

John

 

In all the magazine descriptions of the 458, there is lots of talk about how the car uses advanced aerodynamics to both create downforce (as in the undertray) as well as an admiration of how the engine air-intakes are ram-air ducts behind the rear quarter-window. The car has rear quarter-windows with a curved design similar to the 355 windows, and the fresh air intakes are clearly visible at the rear of the glass. As I said, this is remarkably similar to the air intakes on our cars, as they were originally designed. Somewhere along the way, the intakes got re-routed downward into the side vents, which also serve to provide cooling air to the radiators. Unfortunately, this leads to temperature mixing at the air intake, with probably a hotter-than-ideal intake temperature than is ideal. Probably a bigger issue at low speeds than at high speeds.

Goth is one of our more illustrious/inventive FChat members. He has researched this low speed hot intake air issue and concluded that this is why the idle will typically fluctuate as the cooling fans cycle on/off. Turns out there is some reversal of hot air at the intake level as the fans cycle, leading to hot air intake, and thus to an unstable idle. He came up with a solution which involved a horizontal partition placed above the radiator in the wheelwell to reduce/eliminate this hot air mixing.

This issue at the door vent level is what started me thinking that the change in design to move the engine intakes from the C pillar to the door was likely not a performance-oriented decision, but rather a financial decision. This, presumably, is because it allowed Ferrari to manufacture all engine bays the same on 355's (both coupes and spiders) and therefore to save money on manufacturing.

This is why I was interested in Jay's (UConnHusky) re-configuration of the air intakes back to original design, with the intake hoses leading to the C-pillar. Sorry, not questioning the wisdom or effectiveness of your design, just that I have an F1 car and the pics you show wouldn't work for us F1 owners-- the F1 pump occupies the left rear corner of the engine bay.

Anyway, definitely good work and creative thinking.

John

 

What model year(s) had the airboxes fed from the rear quarter windows? Did the 348 use this method?

I was quite bit surprised to find, while working on my car a couple of weeks ago, that the airboxes were NOT fed from the window "scoops." I was certain they were (but it was my assumption).

 

Yes 348's use the C pillar as an inlet, as did early 355's, presumably up until they introduced the spider. I can only assume they made a change on the production line and wanted to commonize parts for all body styles (different air inlet hoses needed).

The immediate change I notice is SOUND...with that inlet just behind your ear you can really hear some good intake / valvetrain noise, sounds mechanically fantastic! As for power, I've been told my car is quite a bit faster than other 355's by seat of the pants, but after driving it so many miles it's hard to tell. But it's a great mod that makes alot of sense. I too have an F1 with the pump in the way...

Here's the thread I did on the intake upgrade:

http://www.ferrarichat.com/forum/showthread.php?t=240272

 

I have now seen the thread you started a few months back Jay about re-routing your intake hoses. Don't know how I missed it! Kinda what I pictured. Eulk, I too thought my '98 GTB had ram-air intakes via the window location, until I looked down that same window at VVassalo's 348 at Cars&Coffee one morning last year. His window was clearly connected to the hoses we see in the engine bay. That was real ram-air intake. I don't know if later 355's, with their door-mounted intakes, have any ram-air effect. Jay's seat of the pants tells me that there isn't much, if any, ram-air effect with our late 355 setup. Seems though that the 348 hole was bigger in diameter than that on our 355. I wonder if there is a "block off" plate in position in our cars that simply is not there on the earlier cars. If so, to get everthing out of this mod, the block off plate should be removed. Has anyone done this? Am I imagining the roundness of the connection, or is it flattened as on my car? Pics of a 348 intake would be helpful. PAP, anyone with a digital camera and nothing to do this weekend, maybe a shot down the intake of your car would clear this up. Thanks in advance!

Meanwhile, seems like the ultimate setup would be a combination of behind-the-window ram-air intake and relocated filter boxes (but maybe not for us F1 owners).

Thank you all for the work on this subject!

John

 

I don't think the ram effect is going to make a huge difference but it just seems to be a much better way of doing things.

There is no block off plate on my car. It appears they took the original tube and flattened it or cut it in half, more or less, to make it into a half moon shape. If they did not do this there would not be room in between this tube and the fender liner to run the new longer hose up to the radiator areas. If they could have left the tubes at their full size I'm sure they would have. One less part to modify/update and a bit more cooling air to the engine bay.

Yes, a combo. of what Jay did and Themis's relocated air boxes would probably be the best of both worlds.

 

Would be interesting to see.

I wanted to get the bottom halves of my air boxes ceramic coated by Swaintech but it seems they don't want to do it. The person I contacted said they bead blast to prepare the surface (etch the surface, as he put it) but that might distort the aluminum boxes since they are relatively thin.

I would have thought they could prepare the surface in some other way such as chemical treatment/etching if bead blasting is really such a concern. The guy indicated there was no other way. Rather surprising to me....

Anyone know of another quality ceramic coater that might be able to handle this?

 

I simply wrapped the bottom and sides of the boxes with stick on reflective insulating sheets, again with the cost of Ferrari parts I try not to do any permanent mods. If I get a chance today I'll post pics.

Sorry to Themis for the rampant thread hijacking!

 

That was my original thought but there is not much room underneath for a very thick insulation and I was concerned about how to attach whatever material to the air boxes.

I'd still like to go with ceramic coating (and maybe even some insulating material in addition to the coating).

Yes, if you get a chance it would be nice to see photos.

I know there were extra shields on the Challenge cars but the parts are expensive if you could even find them.

Yes, Themis... sorry for the hijack! but I think we're all interested in the same thing and the more ideas/options the better.

 

Are you making the airboxes available?


JD

 

Beautiful Themis. Did you design and build them or did you have them made? I know you put a LOT of work into this.

Of course everyone will want to see a photo of them installed (and know the price if you are selling them)!

 

Much happens when one is away for a little while...

Robbie did a test install of an initial design Niki and I made years back. He was able to give good feedback that stalled that project until a new design was adapted. We are still working on the project as the filter box is only one facet that requires attention. Some 6-7 years ago I made molds and laid out a CF heat shield that extended from the back bumper forward to the rear of the heads... one piece for the 2.7 and one for the 5.2. Really a thing of beauty when all done but extremely complex in shape.

With those two done we did a fair amount of testing and proved to our satisfaction we were headed in the right direction but were still falling short of a complete system. With the economy being what it is we had a visit from a composite person just last week asking if we had any projects we wanted to follow through on.... maybe. There are three more components to this system that need to be designed and molded before its finished. These have been "bubble gum and bailing wire" tested but finished molds not yet made.

I have stacks of research files on projects like this that Niki and I have designed. In practice they do wonders but to take them to production??? Thats a whole different set of issues that I now have a 6 figure ($) education on. Currently there are far too many serious longevity issues to be delt with that have stepped in front of this project for us, at least for the time being.

Race850i,

Nice work and I like your direction. Do some research on when Ferrari brought the Maserati's back to the US some 9-10 years ago. See what you can find regarding engine hydrolock issues with the mule test cars just prior to the US release, some pertinent data you will want to review. I remember discussing much of this with Goth when he was working in this area.

 

hydrolock?????????????? If you think a broken cambelt can do some damage just wait until you hydrolock an engine at full song. Been there and done that in my early years of R&D.

 

If there are any 348/355/360 owners in the Philadelphia area, I have developed a cold air intake modification for other marques that would benefit these V8's. I would like to develop a system for these cars but need a test mule. Anyone who offers would receive the system free of charge as long as you are ok with having your car dynoed (at my expense) so we can quantify the gains instead of speculate.

 

I think the concern is with the low mounted position of the air intake (in the diffuser below the engine) there is the risk of sucking up a quantity of water while driving in the rain, which could enter the engine, causing it to seize?

 

So far we haven't seen these intakes on a car; I think a picture will be very helpful.