Ferrari Experts! Where would I find the Ferrari details for setting my 4 cams to the 348 Challenge, Euro Spider, and/or 348 Competizione specs?
Would it be accurate to say that: Inlet valve opening 12 degrees before TDC and Inlet valve closing 56 degrees after BDC plus Exhaust valve opening 54 degrees before BDC and Exhaust valve closing 10 degrees after TDC gives 300 HP while Inlet valve opening 10 degrees before TDC gives and Inlet valve closing 58 degrees after BDC plus Exhaust valve opening 50 degrees before BDC and Exhaust valve closing 14 degrees after TDC gives 320 HP and if that is accurate...then how do I physically do it?!
Can't verify the specifications. The process is straightforward. You need a degree wheel on the crank. Set to TDC. The cam gears are two pieces with a retaining pin between them. Holes in the parts don't line up perfectly, so rotating one with respect to the other allows the cam timing to change. I'm going off memory, it's been 11 years since I did this. I don't recall the exact specs. I beleive you can change cam position in increments of like 2 degrees, it's not infinitely adjustable. Engine out is way easier. Best, Rob
Thanks. I've got the degree wheel. Engine comes out Monday. I'm taking off the bumpers this weekend to start the process.
I'm also presuming that when you say "TDC" that you mean TDC for #1 cylinder on the intake stroke, yes?
You need to take the engine out to do it unless you want to have a real pain in the but time removing the gas tank. Once you have the engine out its just a matter of getting a degree wheel on the crank, finding TDC (typically I do this with a feeler gauge in cylinder 1) and then you are able to move each cam pully wheel in 2 degree increments if I recall. I am not sure if just setting the cams to Challenge spec will give you the 320 claimed HP as I would be shocked if giving you car a little more overlap in the valves would result in that much of a pickup. If the 320 you quote is the European cars HP its not just the cams, its also the fact that they have taller intake plenums as well. Which is something I am going to fab up here on eMachine-shop one of these nights....right after I get my suspension rebuilt with Rob's excellent new shocks and ES bushings for now, and then finish putting my transmission back in the car, and then finish the COPs conversion I owe FBB after I get mine made and working, and then lastly get my car setup for the track season ahead. Winters go by to fast some times.
Yeah. I'm pulling the engine on Monday. I've already got the 312hp Spider engine...so a bump to 320hp doesn't really sound like much of a stretch. I'd like to use a phenolic spacer under the intake plenum. That would give me a tiny bit of height (helping approximate the taller Euro plenum) as well as cool my air intake charge. I'll polish the valves and (I guess) buy the BMW shims here locally to get the best intake (tight) and exhaust (loose) tolerances. Did you go with adjustable fuel pressure regulators...and if so, how much did you bump up your (starting point) pressure? I'll see if I can get the intake plenum exhuded/honed or otherwise smoothed (and certainly cleaned) while I'm at it. If you get a chance, why don't you mail me your hopped up ECU fuel maps? I'll scan them in on my EPROM reader and let you know what was changed between your version and mine. Who knows, that might show us where some power was left off of the table. I'll be happy to make a backup chip for you, too (that would save you if one or both of your chips ever got fried). I'm pretty certain that it's legal to make one backup copy of your own chip (both of my 348 Spider chips are identical, by the way).
Finding exact TDC on the 348 is a bit tricky because of the piston dwell time (how long the piston stays a TDC before starting its down stroke). You will notice alot of "free play" in the crank before you see any movment in the piston. Best way is as stated above is with a dial gauge in the spark plug hole. This will tell you when you are dead nuts TDC. As for degreeing the cams, trying to explain how to do the process without having the engine in front of me is almost impossiable for me to do. I just don't have the writing or communicatin skills needed to dictate this over the internet. ( I so wish I did!!) If you have the workshop manual it should tell you how to do it. But you need dial gauges which sit on the valve shim. This will show you the exact time the cam lob starts to open the valve. You can see the degrees by looking at the degree wheel. Setting it to where you want it can be a bit of a pain in the butt on the 348 because of the singal belt set set up.
Thanks. That makes perfect sense. Now that you mention it, of course I need to know when the valve starts to open. So, if I understand correctly, I need a dial gauge for my valves and a degree wheel for my crank/cam gear pulley.
Retarding all the cams equally like your suggestion is highly unlikely to change the power... it will simply raise the point in the rpm at which peak power is obtained. Changing overlap can affect power. Retarding exhaust only may help a bit. In practice, human error/ installation technique/ piston dwell time/ and belt length fluctuation will not produce you any real gains/difference from a 2 deg cam timing change if it's currently correct. In any case, dont time using the opening and closing figures... calculate the point of max opening and set to that. Optimise duration and lift with inlet cams for sure (get Euro cams or modified ones... you can grind the base circle from your own maybe)... but DONT run low clearances... set to tolerance. You're better off leaving the engine alone if all you are doing is modifying timing and clearances in a search for power... you'll find much better gains in lightening the flywheel and clutch, and using the best fuel you can find.... both are easy.
Ah, many thanks. Any suggestion for setting the stock cams? Do you mean set my dial gauge to tell me the max opening of each valve, and use the degree wheel at that max opening point? If so, would that be the same degree setting "value" as the specs...or is there an adjustment to the numbers for using the max valve opening rather than when the valve first begins to open? My plan is to re-use my stock 348 Spider cams (U.S.), with intake valves set to .2 and exhaust valves set to .35...unless advised otherwise by you fine gentlemen. Thanks. Are there easy ways to lighten a street clutch (I've got a daily driver...a convertible...race noises wouldn't please the wife). My thinking was to set the cams to the Euro intake/exhaust opening/closing (perhaps I need to rethink that idea), set the intake valve clearances to .2 ("tight") and the exhaust clearances to .35 (loose for cooling)...both within factory specs (I trust). Polish the valves themselves, and polish the inside of the intake plenum. Is this misguided? I'm doing a full 30K Major Service + valve job, and just figured that I'd extract whatever factory spec power was there for the taking while I was at it. Perhaps I'm side-tracked, though??
why are you doing a valve job?? Are you using more oil then normal..or are you experiancing running issues? Do you have low compression numbers on some cylinders? I have had 348's with burn valves as the result of bad injectors and other issues. I was just wondering your reason for going this extra step.
Heard a metal clanging upon startup this week, I'm afraid. Then she ran a bit rough (like clockwork on every other day for 1,000 miles per month for most of 2005) and I suddenly had smoke coming out of the exhaust. When I pull the engine I'll know for certain, but my presumption right now is that I've got valve train damage. The belt appears to be fine (good tension all around, all teeth intact), so perhaps I got debris under the cam gear or perhaps the cam gear flange spot welds gave up the ghost or some such. I need to pull the engine to evaluate.
I would do a complete leak down check of your enigne before removal..and I would also carry out a very careful inpsection of the engine and engine compartment and mountings..on and off the enigne. You may find that inorder to diagnose an issue correctly, you need all functions of the system to be in place before any real problems can be solved.
try a leak down test first. if you persist read a magazine on how to degree a cam in a chevy/ford hotrod mag. that will get you the basic understanding of what you are trying to achieve. FWIW, there are many who say you can extract more power with valve overlap on these cars. I have never seen any extra power that a little driver improvement couldn't correct for. if you are on the track go for it. if on the street don't waste your time.
Thanks for the leak down test (first) advice, gentlemen. I'll do precisely that this weekend or Monday. But...what is it going to tell me about the metallic rattle at idle that I now hear and the smoke from the exhaust? My car knowledge is pretty limited, I admit...all that I know that fits that criteria would be valve train damage (hence, my engine out plan). Is there some remote possibility that the fix could be a non-engine-out affair?! I hadn't really considered such an option...no, I hadn't considered it at all (just not in my knowledge base or in my very limited experience). I am enjoying digging into this car, though.
FBB, this is definitely a street machine. I mean, she's a beautiful Spider. No roll cage. No auto-fire-extinguisher system in back (just my hand-held). Wife rides in her (gets great customer service attention at Saks!). My 3 year old daughter rides in it (yup, I put in a car seat on top of a leather chamois for her when she wants to ride). So I'm certainly listening to your advice. No reason to beat my head up against a wall. My thinking was to take advantage of the situation to add power...but...if that's impractical then I'll take the Easy Street route.
A rattleing sound can be any number of things. I have seen people mistake a nosiy A/C compressor clutch for all kinds of major things. The smoke from the exhuast could be a number of things. One option could be that a coil pack went south and you are running on one side of the enigne only. With a cold engine, odd sounds will be heard because of the crank and ignition lay out on this cars. Check to make sure you are getting full spark on start up. I had a 328 towed in becuase of this very issue. The owner thought he did major damage becuase of the sound of then engine only firing on one bank. Another reason: a mass air flow sensor could have gone bad gone bad causing erractic fuel delivery. Point is, the cause of the issue should be found before any further steps are taken. The last thing you want to do is go through a hugh amount of time and expense, only to put it all back together and find the issue still there! Baby steps first.
OK. Good points. I'm not getting my hopes up, but I can see the wisdom in following your advice for baby steps. Thanks.
For whatever it's worth, I'm not getting any Check Engine codes. My presumption (here's obviously where I could be wrong) was that I wouldn't get a trouble code for valve train damage, but would for bad MAF or bad coil or crazy A/C (which has also been turned off during this affair) or bad ECU (CEL's do appear at startup, run their self-test, then turn off).
To be frank, you're wasting your time. The best advice I can give is to put Euro spec cams in the car, or re grind your own to remove some base circle. if you dont understand what's happening, don't attempt to modify it. FBB hit the nail... prep and repair your car to be stock std (optimised of course), and get driver training from a pro... that way you keep the investment for life, no matter if you sell the car!! if you want to modify it... bolt on some turbos, then un bolt them when you sell the car.
Thanks. Then that's the advice that I'll take. No reason to waste my time, and every reason to be smart about the whole thing. Frankness *is* appreciated.
Is there such a thing as "Euro spec cams" for a 348? Just looking in my parts book, which is dated 1994, and which ordinarily shows different part numbers for anything which has different part numbers for USA versus Euro......they only show one part number for each of the four camshafts. In other words, the four cams are different from each other, but they are NOT different for different markets. Perhaps someone who has a parts book from another year can tell if there were ever listings for alternate camshafts for USA vs. Europe. Not in 1994.
As far as I know that is correct. I have a '90 and the only difference is the valve clearances, and cam timing. However, there is a possibility that the cam lobes on a Competizione are different than on a standard 348. Maybe someone with a GTB could chime in with the number for their cams. The GTB/GTS 348's had 10.8:1 pistons as compaired to the rest of the 348's that had 10.4:1. So maybe they have different cams, but I doubt it. I'll bet the Michelotto preped cars had different cams. Good luck finding those.
