3L to 3.2L, 964 cams, 78 heads & CIS ????

[Pierre911SC]

I will rebuilt my 1982 SC 3L engine & transmission next winter.
While I am there I would like to upgrade the output power.
I am not looking to built a monster machine.

My plan is:
- 3.2 L upgrade (short stroke). = I am getting now.
- Cams grind to a 964 profile. = I will do, when engine apart.
- 3L heads & valves.= On the car now.
- SSI 1-1/2 or 1-5/8 single or dual outlet muffler ???? = I will get.
- 3L CIS = On the car now.

I Think this is a good upgrade, on the other hand, I am told to
get 1978 heads (larger valve ports) and to also get same year CIS
(larger intake manifold).
- What is the price for used 78 heads & 78 CIS ?
- The bottom line is how many horses can I gain with the addition of that setup ?

Need some input.

Thank's
Pierre

Famous quotes:
- If you can't run with the big dogs stay on the porch.
- A second place only means you're the first one to loose.
- Strap a pillow between your knees and hold on.

[fast0911]

I also started with 82SC and did the SS Mod a in 1992.

I kept the stock SC Heads and the power output was just find. However, if you want to go with the 78SC specs you could do a Port/Polish job on the heads to get the same result for about $800. This is cheaper than taking a chance with a set of used heads.
These heads will give you a nice combination which you can also use for other upgrades like carbs and more aggressive cams in future.

You will be happy with the results.

George

[Pierre911SC]

Thank you George,
If I understand you, your are saying to keep and polish my 3L head,
to improve flow.
That was my initial plan, I just might stick to it unless there is major
bennefit in performances.
I am still looking into threads on 78 heads.

Pierre

[fast0911]

Pierre,

Yes, Polish them.... But also have the heads ported to the 78/79 specs... This means you need to increase the intake port from your current size of 34mm to 39mm and the exhaust ports from 35 to 38mm. The ideal thing to do is to have the individual that is doing your heads include this Port/Polish and intake/exhaust work in the price. At the end of the day you will have a better set of heads than if you bought an used set.
This is what I am doing to my heads at this moment since I need to breath a little better now that I am going with a more aggressive cam and a set of 46mm PMOs....

I think I may have sent you an email about the parts I have for sale (Pistons & 964 Cams) in case you are interested they are on the "Sale Post" here on Pelican. I'm trying to help finance a new set of 10.5CR Pistons

Also, if you need someone to do your heads there are a lot of guys here on Pelican that can guide you to some of the best guys to trust your heads to do the Port/Polish trick to them.

George

[OldTee]

Go slow here and get a lot of feedback. Trust me.

[Pierre911SC]

One thing I did not mention was RELIABILITY.

This is my first Porsche I bought 3 years ago.
It got 155,000 miles on the engine and it's very strong
occasional blue puff of smoke on cold start and oil dripping
during storage (winter months that is).
I drive the car as it was meant to be ie:
Quick, shift on the high end of rev....
I am extremely satisfy with the reliability of that vehicle.
NOW:
If i get involved in upgrading power I would expect the same reliability.
I dont want to spend my time off (28 days on 28 off) in a garage
fixing the thing.
I need some input from you gentlemens, which way to go.
Pierre

[juicersr]

Pierre, BEAUCOUP threads on the subject of larger vs smaller heads, 3.2SS mon ami. RECHERCHE s'il vous plait, et se trouver.

Just my opinion, but unless you are making dramatic changes in piston compression, changing to EFI or ITB/ Webers, twin plugging, etc. you will not be able to tell difference between large and small port heads. Save yourself $$$ and just invest in a good set of Mahle P/C's and SSI's and 964 cam, do the bottom end as well, and you will have a fun motor with a little more power than what u have that will go another 150,000 miles or more.