Hi All, I'm on the lookout for a complete set of 74 308 camshafts for my GT4 rebuild. My shafts are pretty bad. http://www.ferrarichat.com/forum/showthread.php?t=233865 If anyone has some euro camshafts in good condition and is willing to part with them please PM me? Cheers George
looks like a common problem. can't they be fixed? i know of two sets with the same issue that were fixed.
Built up, hardened and reground? Do you remember who did them? Thats a lot of lift George needs regained.
I got Graeme Vincent to organise it for a 328 a couple of years ago and Black Stallion did a set for me for a 308.
Did they have to add metal? George's sound like they may have been undersize on lift even before the wear.
I might be wrong but I think that they might be too far gone.I had to replace one exhaust cam when I rebuilt as it was excesively worn and from memory it didn't look as bad as George's.I bought mine new from Ferrari UK for $900 2 years ago.I almost bought one from the US when I realised that I needed a Euro cam.They rarely come up on Ebay so I think the search might be long.Try Eurospares in the UK or maybe new might be the only way...ouch!
Clive Stenlake at Clive Cams in Victoria will be able to fix these for you. 03 97585977 Much cheaper than buying new or 2nd hand cams. He did my Daytona cams which were equally far gone, plus he has all the profile data for Ferraris.
Also, make sure you get your oil pump checked out to ensure you're getting adequate pressure at idle speeds, plus increase your idle speed a little (I run 1000rpm) to avoid the accelerated wear problem. Another trick is to ensure that your valve shims are the correct quality and in good condition. Many mechanics have a box full of 2nd hand shims which get swapped from car to car as they do valve clearances. It's worth buying yourself a selection of thicknesses and starting out with new shims in your rebuilt engine. Buy the shims from a FIAT/Alfa place - they're the same as 2 Litre Fiat twincam.
Thanks Gent's for the responses, I've managed to get a set of US spec cams from Marc @ Enzotech. I just need to get my BSM dizzy modified back to spline drive from dog drive. Looks like early euro spec cams are very very rare and expensive so the US ones will have to do. I measured them up and get an average lift of 8.6mm inlet and 8.1mm exhaust which is a hell of a lot better than the cams I had. Very little variance from lobe to lobe. Cheers George
well done. i doubt you'd notice the difference, really...i went from aussie spec to euro ones and didn't notice anything. maybe a dyno would prove otherwise.
UK/Euro spec cams are 8.8mm inlet and 8.1mm exhaust. You can easily get Clive to grind 0.2mm off the reverse side of the lobe to achieve euro spec. The early P6 cams are 9.3mm inlet and 8.6 exhaust. You will notice that the engine doesn't want to rev as freely with the US cams.
Phil, I thought about having the cams ground on the base circle to get closer to euro but the $$$ on this rebuild are starting to add up. As PP commented, I doubt wether I'd notice the difference anyhow. From my experience the noise and shove of my GT4 (before rebuild with dodgy cams and dodgy other bits) was good enough for me and I didn't really want to rebuild it but thanks to the great folks at the taiwanese EMPI factory here I am..... I didn't think to measure the valve clearance before I stripped the engine down for rebuild but I suspect that the valve clearances were way off. It's funny, a couple of the lobes were fine and had good shape but the rest had a definite hammer on the slope up close to the tip of the lobe. My theory is that the valve clearences were way off and probably hadn't been check for some time. I too should have checked them when I bought the car but I didn't. I think the previous owner treated the car like a garage queen as it has a set of 10 year old Michelins on it that fell apart at 110kph 30Klms into my drive from Sydney to Brisbane. I though did not treat the car as lightly. After warming up I'd take the engine to 7700rpm on several occasions per run, not sustained but redline none the less. So I probably damaged the cams in the last 12 months. This rebuild has given me an appreciation of what damage can be done and how easily it can happen if items such as valve clearance is not right. I think that I'll drop the rev limiter to 7K and try to keep things under 6500 from now on.
you shouldn't talk to that guy...he'll lead you up the garden path. i have a theory to add to the 'reusing old shims' theory....... car sits around for month after month then gets started up.....everything in the top end is completely dry....some dopey bugger revs it when it starts cold....whammo....metal on metal...hardening goes and it's quickly downhill from there. add to that lack of oil changes over 30 years and less than top quality oils...it makes it easy to understand. i reckon you'll be happy with the US cams. There'd be much more gain in the BSM ignition unit than you'd lose in the cams anyway. you're doing well....better than i could do, that's for sure.
