3.3 turbo engine camshafts recommendations?

ornas · ornas's Garage

Hello, I’m rebuilding 3.3 turbo engine. And don’t know what type of camshafts should I go for. My current setup is:
Stock crankshaft
Carrillo H rods
3.3 stock cylinders with JE 8,5:1 compression ratio
Garrett gtx30 gen2
Aftermarket headers and intercooler.

Dbilas dynamic are offering
Duration: : 276°/272°
Peak timing: : 108
Valve lift: : 10,7/ 9,8

That seems to be a bit to drastic for such low compression ratio. Please correct me if I’m wrong. What spec cams you will recommend for street application?

matthepcat · matthepcat's Garage

Depends on what you want the car to drive like off boost and ultimate power. SC cams are popular for street driving, low RPM drivability. 964 cams are a good compromise (still mild), but more mid-range power. Since you are running a smaller turbo for a 3.3, you can probably get away with a slightly more aggressive grind (top end).

crb07 · crb07's Garage

I have a pair of very low mileage SC cams by Webcam if you go that route.

ornas · ornas's Garage

Could someone tell me duration and valve lift of SC and 964?

dannobee · 01-26-2022, 04:35 AM

Web Cam Racing Cams Inc. / Porsche 911 SOHC 12v

http://www.drcamshafts.com/911profiles.htm

T77911S · 01-26-2022, 05:24 AM

I put SC in mine, wish I had the 964.

stownsen914 · 09:23 AM

Looking at the Dbilas dynamic cams, it's hard to tell whether their specs are seat timing (full duration), or measured at 1 mm or .050". That's important for making a valid comparison with what you'll see Web, DR, and others offering.

M5guy · 01-27-2022, 04:15 PM

Mine has new Webb 964s.

gsxrken · gsxrken's Garage

EFI vs CIS needs to be known too. You can use more cam with EFI.

quattrorunner · quattrorunner's Garage

With the gtx30 the 964 might be better. The gtx30 should be way fast boosting and you wouldn’t need the sc cams. That turbo might even be too small?

VZ935 · VZ935's Garage

I got a couple of these if you want...

s5uewf · s5uewf's Garage

I just had a rebuild by TK and had Elgin SuperSC installed, which are in between SC and 964. Running in an EFI setup. They seem fine at the moment - good at all rpms, and I still need to get to a dyno for some ultimate fine tuning, so there is still more to be had I believe. Nothing on a track so cannot speak to performance other than on local roads.

It is hard to select without first hand experience ... best of luck with your choice.

Alan L · Alan L's Garage

I have same cams - got them from TK.
I don't have much to compare them to - I changed a few things at the same time. But I am happy with the range of performance of the beast. Pulls well once on boost, all the way thru the range.
Off boost seems OK, but I try not to spend any time there, but around town I think it would be fine.
Alan