| Author |
Message |
Russ Turner (Snj5)
Junior Member
Username: Snj5
Post Number: 75
Registered: 2-2003
| | Posted on Thursday, April 10, 2003 - 9:03 am: | |
Here are the specs on V-8 perf. cams recommended by Frank Capo (terrific guy)in Aus. - about Aus$1500 ($49.45 American - just kidding). Very similar to P-6 @ 290 duration, but different timing
lift .410
Intake 43/67
Exhaust 71/39
duration 290/290
overlap 82
lobe center 104
For comparison, a 250 GT SWB:
intake 44/75
exhaust 74/43
duration 299/297
overlap 83
lobe center 105
328 (similar to all k-jet V-8s)
intake 16/48
exhaust 54/10
duration 244/244
overlap 26
lobe center 109
Might want to check my math in public.
Hope this helps - I'm certainly learning a lot.
best to all
rt |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 203
Registered: 7-2002
| | Posted on Wednesday, April 09, 2003 - 9:55 pm: | |
Anyone know anything about the specs on the hi-po cams available from superformance in the UK? About $1500 for a set (new). |
William Badurski (Billb)
Junior Member
Username: Billb
Post Number: 162
Registered: 6-2001
| | Posted on Wednesday, April 09, 2003 - 9:33 pm: | |
If you're looking for these cams, contact Laurie at Web Cams in CA. She's currently reprofiling a set of stock cams for a Daytona I'm working on. |
'75 308 GT4 (Peter)
Advanced Member
Username: Peter
Post Number: 2645
Registered: 12-2000
| | Posted on Wednesday, April 09, 2003 - 4:20 pm: | |
The Ebay auction ended last month:
The P6 cams:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2408704234&category=33614
The carbs (I made a mistake, they were 44mm DCNF's):
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2408705274&category=33550 |
'75 308 GT4 (Peter)
Advanced Member
Username: Peter
Post Number: 2644
Registered: 12-2000
| | Posted on Wednesday, April 09, 2003 - 4:07 pm: | |
FWIW - In respect to carb mods:
One of the original Forza articles about the P6 cams (written by Tony Palladino), stated that they (Ferrari) retained the 40 DCNF's but opened them up with 36mm chokes. This is good for the needed high flow at high RPM, but not so fun tooling around town... Of course, jets and I believe tubes were changed to suit. Maybe the reason for keeping the stock size carb bodies was to comply with FIA homologation requirements for a certain class of racing...
I had scanned that article, but I can't seem to find it on my computer...
FWIW part II:
I recently saw a complete set of P6 cams and matching 42mm DCNF's on Ebay... Big bucks! I don't know if it sold or not. |
Sean F (Agracer)
Junior Member
Username: Agracer
Post Number: 77
Registered: 2-2003
| | Posted on Wednesday, April 09, 2003 - 12:41 pm: | |
Don,
This was also discussed in last months Forza Magazine. Next time I see you, I'll give you my copy and you can read it.
Norwoods in Dallas did a rebuild on a 3.0 Engine and talked about performance upgrades. He (can't recall his name - worked for Norwoods in Dallas)noted several options for upgrading the cams. Norwoods said to have them welded, and re-ground at a place called Cam Motion to change the lift and duration of the cams. But, he noted these changes are only really effective if you go to higher compression pistons 10.5:1 for carb cars, and 11.0:1 for QV cars. They quoted 260-300+ HP when you make these changes depending on other factors (Carb, FI, QV, etc). Price was ~$1500 for having your existing cams welded and ground, $3500 for machined from new billet. Can't remember what the upgraded pistons were.
I'm still thinking about what we discussed last Saturday. Maybe my car could be the "experiment" and then we could do your car. Of course, I have to FIND a car first. |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 201
Registered: 7-2002
| | Posted on Wednesday, April 09, 2003 - 10:29 am: | |
JRV
Thanks. I'll look around. Will come back to you if indeed I come up short and buy the cams
Philip |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1246
Registered: 11-2002
| | Posted on Tuesday, April 08, 2003 - 10:05 pm: | |
Don,
as Phillip states real P6 cams are unlikely to be laying around, however Koenig used to advertise 308 cams that are probably knock-offs or a very simular grind. No you don't have to do pistons at the same time, however if you don't, some serious checkng would be in order for valve to piston clearance, as the P6 (and simular grinds) have higher lift, and custom pistons usually have deeper valve relief pockets and the springs normally get pressure checked and shimmed for higher rpm use when the heads are off. The P6 cams raise the redline to about 8200-8400, although I've seen the motors twisted higher on occasion..;-). I know someone in the US is grinding 308 high lift cams, because I did a motor with a set a couple years ago. Can't remember who off the top of my head, try a web search.
Phillip, jetting for cams or cams & pistons is fairly striaght forward. All the Comp Daytona info is readily availible with a little looking. I have lots of old notes somewhere if you get to that point. |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 199
Registered: 7-2002
| | Posted on Tuesday, April 08, 2003 - 8:44 pm: | |
Hans, I am in the Midwest.
Don, the are an OEM and largely NLA item. Jeff Howe may have some. |
Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1071
Registered: 4-2002
| | Posted on Tuesday, April 08, 2003 - 7:30 pm: | |
Philip: What area of the country are you in? There is a chassis dyno shop in Portland whose operator is familiar w/Webers. This helps in that intelligent guesses at jet changes result in the need for fewer dyno runs, and less $$$$. |
Don McCormick (Dandy_don)
Junior Member
Username: Dandy_don
Post Number: 63
Registered: 2-2002
| | Posted on Tuesday, April 08, 2003 - 7:30 pm: | |
OK, JRV you have my interest. What do the P6 cams cost? Anything tricky about installing them? Would one need to install high compresion pistons as well or could you leave the engine in the car and just do the cams? Maybe do the pistons later if I ever take the engine out. I might take the 25-30 HP if I could avoid the engine out. Phillip, if you get a line on some P6 cams perhaps we could buy together and get a better price. Don |
Newman (Newman)
Intermediate Member
Username: Newman
Post Number: 1192
Registered: 12-2001
| | Posted on Tuesday, April 08, 2003 - 6:29 pm: | |
Only a dyno and a HC monitor will tell you what jets are ideal whether its stock or majorly modified. You will have to make changes for sure for the HP increase. Probably mains, idles and AC will all need a change as well as pump jets. |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 198
Registered: 7-2002
| | Posted on Tuesday, April 08, 2003 - 4:32 pm: | |
Sean
Sorry, I think I mislead you, others. My question more accurately stated is: what's the jetting required on a 77 with P6 cams and stock carbs. Anyone?
Philip |
Sean F (Agracer)
Junior Member
Username: Agracer
Post Number: 74
Registered: 2-2003
| | Posted on Tuesday, April 08, 2003 - 3:31 pm: | |
Phil,
Do a search for 308 carb rebuild and rejet.
Don just did his and their is lots of discussion about it. |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 197
Registered: 7-2002
| | Posted on Tuesday, April 08, 2003 - 2:48 pm: | |
Anyone have any knowledge of jetting required with the stock carbs?
Philip |
Russ Turner (Snj5)
Junior Member
Username: Snj5
Post Number: 69
Registered: 2-2003
| | Posted on Tuesday, April 08, 2003 - 2:20 pm: | |
jrv-
thanks for the info; very helpful.
rt |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1240
Registered: 11-2002
| | Posted on Tuesday, April 08, 2003 - 8:12 am: | |
>>was there enough low end to keep a car daily streetable? <<
I'm not real sure what problms you are having with bottom end ? Little motors require the use of healthy amounts of foot to accelerate quickly, no matter if they have mods or not.
The car is very streetable. The changes barely affect bottom end, the gains are in mid-range and top end.
Dandy Don, glad to hear the Distrib rebuilds worked out well, a well running engine always starts with the basics and builds from there.
On the P6 cams or simular and compression increase the HP gain is likely in the 25-35 range, which doesn't sound like alot until you consider that the torque improves by about 20%, is lower in the rpm band coupled with a much longer torque curve. What you get is an engine that pulls better & harder earlier and over a larger rpm range that really releases the potential of the 308 carbed motor. If you think about it, 275-285 HP out of a 3L motor that runs great on the street is not bad. |
Sean F (Agracer)
Junior Member
Username: Agracer
Post Number: 68
Registered: 2-2003
| | Posted on Tuesday, April 08, 2003 - 8:10 am: | |
Don,
Did you get your timing reset on Sunday and does it idle a little lower now? When I left on Saturday night you said it had never idled that well since you bought the car.
Sean |
Russ Turner (Snj5)
Junior Member
Username: Snj5
Post Number: 68
Registered: 2-2003
| | Posted on Tuesday, April 08, 2003 - 1:15 am: | |
While I can see the power advantages - was there enough low end to keep a car daily streetable?
Anyone else using P-6 or long duration or modded cams on 8cyl cars that could comment on streetability? Also, were carbs re-jetted?
many thanks
russ |
Don McCormick (Dandy_don)
Junior Member
Username: Dandy_don
Post Number: 57
Registered: 2-2002
| | Posted on Monday, April 07, 2003 - 3:54 pm: | |
JRV, what sort of HP increase (ballpark) would one expect from the P6 cams, high compression pistons, and ported/polished heads? I have a 79 GTS and am investigating means of increasing power output (as so many of us are). I know much has been written on the subject but perhaps you would indulge me.
Also, as you had suggested in a previous thread, I sent my two distributors out to Continental Motors in Hinsdale IL to have the advance mechanisms calibrated/adjusted and they promptly returned them along with certified curves as tested. They were great to deal with and did what they said they would do. Car runs great. Don |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1239
Registered: 11-2002
| | Posted on Monday, April 07, 2003 - 12:37 pm: | |
Used them and driven them, with higher compression pistons also of course and don't have any complaints. In fact it's a pretty immpressive upgrade. |
Philip Airey (Pma1010)
Junior Member
Username: Pma1010
Post Number: 195
Registered: 7-2002
| | Posted on Monday, April 07, 2003 - 11:01 am: | |
Anyone driven a 308 with P6 cams and can comment on drivability. Given the high duration and overlap (290 IIRC), my expectation is they produce a pretty soggy motor below 3500 rpm, but I am curious on anyone's experience.
Philip |