|
|
|
|
| Author |
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Urgent help please...cam question...
Sent my 88 930 cams to webcam due to pitting on one cam...
I was told by the prior owner that the motor had SC cams... Motor was modified up the wazoo, running 1.3 bar or so when I bought it... The power is very linear, not peaky, and I have tracked the car with no issues, no "on/off" turbo spikes, etc. Webcams called, and said my cams are stock 930 profile?!?!? I find that really really hard to believe, and they will recheck... They ran it on a "CAM DOCTOR" machine... Now the cams, under than 1 lobe, looked great. Minor pitting on one lobe. I have no issues with the way the car drives... If they are truly stock 930 cams... Should I leave it? Regrind to SC? My only issue with regrinding is that I suspect you need to take off a lot of material, and don't want to be left with issues... Car ran great... |
||
07-03-2019, 09:35 AM
|
|
|
Registered
Join Date: Jun 2003
Location: Camarillo, Ca.
Posts: 2,418
|
Weird, I did not know they had a cam doctor....SC cams would be a great grind for the turbo. Personally, I send all my cams to Dougherty Racing Cams.
__________________
Aaron.  F.S. 1965 Solex engine w carbs/cleanerBurnham Performance https://www.instagram.com/burnhamperformance/ |
||
|
07-03-2019, 10:05 AM
|
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Quote:
|
||
|
07-03-2019, 10:13 AM
|
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Ok... here's the update.
They reported that it is a stock 930 grind. Which really blows my mind, as its nowhere near as peaky as I thought it would be... $500 to regrind to stock, $1200 to do as an SC cam... Going to stay stock for now... Car ran well... Are the 930 profiles from the later cars less "peaky?" Is the cam profile the same as for the early cars? I still can't believe it was a stock 930 profile... I would expect no power and then WHAM. Which, isn't what I have. Throttle is very linear... Prior owner wasn't a car guy. Owner prior to that has mods listed as: SC Cams Hi Flow fuel head Boost regulator Aftermarket exhaust Thanks for the help! With time, slowly going back to "stock-ish." |
||
|
07-03-2019, 12:27 PM
|
|
|
Registered
Join Date: May 2004
Posts: 874
|
My advice would be to see the cam report before making any decision. Ask for the report to show each lobe on both cams as well. Then you can determine if the cams you have, whatever they are, are good.
If there is any deviation between lobes, you can then make a better decision on what to do. Pointless putting back cams that are badly made. |
||
|
07-04-2019, 08:54 AM
|
|
|
Registered
Join Date: Nov 2017
Location: Houston, TX
Posts: 870
|
Peakiness on a 930 has more to do with early turbo design than cam. One of the reasons to put newer turbos is the improved operating range (or to move the operating range to a different rpm band), rarely do you need more absolute pressure.
What turbos are on your car? |
||
|
07-04-2019, 10:31 AM
|
|
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Will keep you all posted.
As of yesterday I just advised to leave the same profile with no changes. They will just grind very slightly due to pitting in one cam... That’s all I know for now... |
||
|
07-04-2019, 12:33 PM
|
|
|
Registered
Join Date: Jul 2013
Location: Brisbane, Australia.
Posts: 2,586
|
Rather than regrind then, how much do they charge for a brand new cam?
|
||
|
07-04-2019, 01:02 PM
|
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Quote:
Again, my cam looked great other than slight pitting on one cam... was going to just do one cam, but folks suggested doing both... Some suggested buying used sc cams... don’t quite get the math there... seems those sell for $600+ in good shape. You still need to regrind to new, so it matches the reground rockers... that’s $600 more right there, so it’s a $1200 cam total cost... All the posts on here say if you regrind a cam, you need to grind the rockers too...and you can’t use newly reground rockers on an old cam... This gets pricy fast... The cost to rebuild these motors, as most already know, easily hit large numbers... |
||
|
07-04-2019, 02:11 PM
|
|
|
It's a 914 ...
Join Date: Jan 2008
Location: Ossining, NY
Posts: 4,690
|
It is not typical to regrind cams that are in good condition, if you get some good SC cams. Rockers, yes regrind.
|
||
|
07-08-2019, 03:26 PM
|
|
|
abides.
|
You can't just use SC cams... they are missing the scavenge pump drive.
__________________
Graham 1984 Carrera Targa |
||
|
07-09-2019, 12:25 PM
|
|
|
Registered
Join Date: Apr 2007
Location: wisconsin
Posts: 2,553
|
Quote:
True or not, don't know. After reading dozens of threads your head hurts... you touch one thing, you need to touch another. And you very easily find out how a rebuild hits $5000+ |
||
|
07-11-2019, 04:23 AM
|
|
|
|
Registered
Join Date: Oct 2008
Location: Nash County, NC.
Posts: 8,467
|
You went looking for answers,
You have to ask yourself what is the answer when you factor out the profit motive and no extensive experience, merely repeating what they have read or seen pictures of someone else’s problem. Your biggest question is the cut of the cams, if there is no markings or part number has not been removed, consider to stock cut It’s taken 30 + years to pit the lobe, does the lobe still support the majority of the rocker? For less money have a drive installed on a set of SC/Carrera cams, open up to 3.4, higher compression JE s you can use full finned carrera cylinders in the turbo. Still less than quoted prices. Bruce |
||
|
07-11-2019, 10:03 AM
|
|
1984 Porsche Carrera Targa
