Camshaft change, how about the distributor?

[Fidalgo911S]

I'm currently rebuilding my 1974 911S motor. Just about everything is back from the machinist. He didn't like the wear on my camshafts and recommended I get them sent out for a regrind. I've e-mailed John Dougherty based on the many recommendations on this board. I asked John about some options to "broaden" the powerband and he recommended a re-grind to the SC profile.

If I do that change, do I need to get my distributor re-curved or will it work just fine?

(Note: with the exceptions of the case machining, SSI's and M&K muffler, the rest of the motor will mostly be unchanged from stock. Yes, I'm keeping the CIS.)

Thanks.

[304065]

Nate,

Here's a thread in which I asked basically the same question. The Guru of Portland, may he be blessed with health and prosperity in the New Year, opined that the 2,4 curve (the purple one) was more appropriate given the reformulated Panther Pee that is sold to unsuspecting motorists under the name "Gasoline." Now, I would caveat that by saying that I'm using DC Supercup on 102, which is a different lobe profile than SC.



Advance curves for Modified Engine

[Fidalgo911S]

John,

Thanks for the light reading. I'm a fairly simple caveman (pull back on the stick=houses get smaller, push forward on the stick=houses get bigger), but I'm fairly convinced I need to get some work done on my Bosch distributor.

This point was very evident when I replaced the 009 dizzy on my 914 with a Mallory Unilite. The difference was dramatic, well... as much as it can be with a 914. With a change in camshafts and, as I read, 30 years of fuel "refinement", It's a smart thing to do.

Since I'm a card-carrying member of the Beaver State, I'll give that gentleman a call and see what his recommendations are. Thanks for the input.

Nate

[Steve@Rennsport]

Originally Posted by Fidalgo911S

John,

Thanks for the light reading. I'm a fairly simple caveman (pull back on the stick=houses get smaller, push forward on the stick=houses get bigger), but I'm fairly convinced I need to get some work done on my Bosch distributor.

This point was very evident when I replaced the 009 dizzy on my 914 with a Mallory Unilite. The difference was dramatic, well... as much as it can be with a 914. With a change in camshafts and, as I read, 30 years of fuel "refinement", It's a smart thing to do.

Since I'm a card-carrying member of the Beaver State, I'll give that gentleman a call and see what his recommendations are. Thanks for the input.

Nate

Hi Nate:

A hearty thanks to "He who must not be named" for the accurate information posted above.

I am a "pull on the stick until the rivets pop and the WSO pukes, kind of person", but your caution about the suitability of today's gas and the advance curves are well placed. Your stock advance curve is well suited for our 92 octane fuels and and any CIS-compatible camshaft profile.

In short, you don't need any re-curving for your new configuration. My only suggestion would be to eliminate the points with a Pertronix for a more accurate timing signal and better idle.

Hope this helps,

[Fidalgo911S]

Originally Posted by Steve @ Rennsport Systems

I am a "pull on the stick until the rivets pop and the WSO pukes, kind of person"

Thanks for the input Steve. That does help, and I'll take your advice and make the change to Petronix. Take care,

Nate