CAMSHAFT TIMING

**Patrick M** · 25th June 2020, 09:36 PM

Hi Blokes,
I am currently doing a top end rebuild on the old 3.5 V8 I, rebuilt heads, rocker gear, camshaft, cam followers, timing chain and gears to both crankshaft and cam.
I have in the past on other V8,s used camshafts with a slightly different grind and dialed them in with a two degree advance this made a very noticeable (in a positive way) difference to the performance of the engine.
With this engine though, I am replacing the camshaft with a standard grind unit but was wondering whether I should put a two degree advance or retard on it when setting it up and is it worthwhile with a standard camshaft grind?
If anyone has done this can you please give me the benefit of your experience?

Regadrs:-
Patrick M

**justinc** · 26th June 2020, 05:23 AM

If using a std cam profile, then leave at std marks. However it wouldn't hurt to check actual lift with a degree wheel, and may be advantageous to adjust if the specs are out due to mass production tolerances. My previous experience has always been successful leaving standard cam timing alone.

**Patrick M** · 26th June 2020, 10:51 AM

Originally Posted by justinc

If using a std cam profile, then leave at std marks. However it wouldn't hurt to check actual lift with a degree wheel, and may be advantageous to adjust if the specs are out due to mass production tolerances. My previous experience has always been successful leaving standard cam timing alone.

Hi Justin,
Thanks for your reply, you are spot on with your comment on mass production and specs becoming distorted during the manufacturing process and yes I intended dialing the new camshaft in just in case.
I have dialed in camshafts on a number of occasions but it has been a few years since doing so, I still know the procedure and steps to go through but are not to sure of the amount of lift that the standard camshaft has to be set at on TDC.
I was wondering if you have the specs handy and if you do would you mind sharing them with me?

Regards:-
Patrick M

**justinc** · 26th June 2020, 03:43 PM

Originally Posted by Patrick M

Hi Justin,
Thanks for your reply, you are spot on with your comment on mass production and specs becoming distorted during the manufacturing process and yes I intended dialing the new camshaft in just in case.
I have dialed in camshafts on a number of occasions but it has been a few years since doing so, I still know the procedure and steps to go through but are not to sure of the amount of lift that the standard camshaft has to be set at on TDC.
I was wondering if you have the specs handy and if you do would you mind sharing them with me?

Regards:-
Patrick M

Hi, I'm sorry no I haven't, it has been many years since I've fitted a cam to these, too!. The EFI cam is the best profile for allround use, maybe Google 1986 on 3.5 EFI cam specs?

**rick130** · 26th June 2020, 04:00 PM

And a FWIW, retarding the cam timing moves the power and torque up the rev range, advancing it moves it down.

**rover-56** · 26th June 2020, 04:16 PM

Well, Rick's experience doesn't match mine.
I have often advanced the camshaft 2-3 deg on various engines to move the torque peak up a bit.
Most recently when I rebuilt the S3 2.6 I advanced the camshaft 3 deg. (took a whole day of fiddling) and the difference is very noticeable, you can hear and feel it. The std timing puts the torque peak at 1500rpm (where Rover says it is)
Advancing 3 deg. puts it at2200, and you can feel and hear it in the exhaust note on hills.
Also advancing gives you a bit of insurance for when the chain and sprockets wear a bit, the timing comes back closer to std.
Terry

**Blknight.aus** · 26th June 2020, 04:32 PM

Originally Posted by rover-56

Well, Rick's experience doesn't match mine.
I have often advanced the camshaft 2-3 deg on various engines to move the torque peak up a bit.
Most recently when I rebuilt the S3 2.6 I advanced the camshaft 3 deg. (took a whole day of fiddling) and the difference is very noticeable, you can hear and feel it. The std timing puts the torque peak at 1500rpm (where Rover says it is)
Advancing 3 deg. puts it at2200, and you can feel and hear it in the exhaust note on hills.
Also advancing gives you a bit of insurance for when the chain and sprockets wear a bit, the timing comes back closer to std.
Terry

this^^^

mr used to have a couple of nice cams for the 3,5/9. might be worth a ring.

**Patrick M** · 26th June 2020, 08:57 PM

Originally Posted by rover-56

Well, Rick's experience doesn't match mine.
I have often advanced the camshaft 2-3 deg on various engines to move the torque peak up a bit.
Most recently when I rebuilt the S3 2.6 I advanced the camshaft 3 deg. (took a whole day of fiddling) and the difference is very noticeable, you can hear and feel it. The std timing puts the torque peak at 1500rpm (where Rover says it is)
Advancing 3 deg. puts it at2200, and you can feel and hear it in the exhaust note on hills.
Also advancing gives you a bit of insurance for when the chain and sprockets wear a bit, the timing comes back closer to std.
Terry

Yep I have found the same thing with the cams that I have dialed in and advanced them.

**Patrick M** · 26th June 2020, 09:01 PM

Hi Blokes,
Has anyone out there got the specs for dialing in a standard 3.5 EFI cam, I have done the Google thing and come up with nothing.
Regards:-
Patrick M.

**rick130** · 27th June 2020, 06:45 AM

Originally Posted by rover-56

Well, Rick's experience doesn't match mine.
I have often advanced the camshaft 2-3 deg on various engines to move the torque peak up a bit.
Most recently when I rebuilt the S3 2.6 I advanced the camshaft 3 deg. (took a whole day of fiddling) and the difference is very noticeable, you can hear and feel it. The std timing puts the torque peak at 1500rpm (where Rover says it is)
Advancing 3 deg. puts it at2200, and you can feel and hear it in the exhaust note on hills.
Also advancing gives you a bit of insurance for when the chain and sprockets wear a bit, the timing comes back closer to std.
Terry

Originally Posted by Blknight.aus

this^^^

mr used to have a couple of nice cams for the 3,5/9. might be worth a ring.

Funny, every race engine we built (Ford 1600) where the stock cam was forced on us by regs (Ford GT cam) we'd retard the cam timing, the more retarded, the more it moved the torque peak up the rev range.
Might depend on lobe centres

Road engines I've always run at stock timing.

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