Rebuild a SWB T engine to S : Opinion please !
 

Hello guys,

I currently own a 68 SWB 911 T since a year. It is all matching numbers and in very good condition.
Since a couple of weeks, I have a kind of ugly chain noise at the back... near 3000 rpm. Thus, I was planning a carrera tensionner upgrade. It may be the occasion for a rebuilt...

My question is that if I have the engine rebuilt, should I keep the T componments, or upgrade to S componments, the price of the 2 solutions being almost equivalent...
What are the engine parts I will have to change to get an S engine : Pistons ? Cylinders ? Cams ? Valves ?

Should I simply swap engines ?

And by the way, how do you diagnose that it is time for rebuilt ?

Thank you for your precious answers !
http://club911net.free.fr/membres/Dooop_big.jpg

Dooop SmileWavy

Get a compression test will give you an idea of what condidtion the engine is in.

BTW what is the name of that red?

Are there many early 911's in France?

Gidday Aussie,
Thanks for the advise. From what compression score is it time for a rebuilt ? a difference between cylinders, under 8 ?
BTW, this red is a... Ferrari red ! don't blame me, it is the previous owner's choice, but so nice !
In France, classic 911s are becoming more and more desirable, reaching astonishing prices ! a nice S is now around 35000€ (US$ 40000)

see ya down under !

Doop,
I'd first do a compression check to see if you need a rebuild. Does the car use much oil?

since you have weber Carbs it's easier to have your engine changed to S specs. You would have to change just your cams and pistons and maybe your crankshaft but that's not 100% necasary.

There are also other options on a rebuild like that. I, for example, have S-cams but a largely mechanically stock L engine, otherwise. The thing absolutely screams at high revs. Jluetjen on here has the opposite -- he's got S pistons with T (I guess?) cams. Unfortunately we wanted to dyno the two cars to get a feel for the difference between the two, but didn't get a chance to this year.

Beautiful car! Gotta love those rally lights.

For a street car I would go with E cams. The power comes on earlier in the RPM range. Go with the S pistons for the increase in CR. My opinion of course.

Good luck!
BK

Don't forget the distributor also. I don't think you want to use a "T" advance curve with E or S cams.

Gorgeous car Dooop. I am not a big fan of red Porsches in general, but I really like yours!

Hello everyone, and thank you for these replies !

So you would suggest, after a compression test, the following upgrades :
- cams replacement : S or E cams
- Same pistons if they are in a good shape, S pistons otherwise

About the distribution, does the operation consists on a tune up, or a replacement ?

BTW, what does "increase of CR" means ??? :confused:

:cool: cool if you like the colour, I am getting used to, even if it is a non porsche...
These rally lights came as an option from the first french importator of P-cars : Sonauto.

Other advises very welcome !!!
Dooop

CR is Compression Ratio - "rapport de compression" ? The "S" pistons will result in a significantly higher CR than "T" pistons, which increases power.

The distributors can be recurved/rebuilt to the advance curve you desire.

Considering your replies, I am thinking about an other solution, "money-wise oriented" :
I have the opportunity to get a brand new 2.0 110 hp engine (exactly same as mine) which is a 1970 914-6 flat6.
It has been used ony a few hours, in mechanic lessons (carbs tuning) of a french mechanic school.
The price is fair, and it comes complete except carbs and exhaust system.
I am planning to install this engine in my car (losing the matching numbers advantage) and stock the original engine for further rebuilt (and upgrade).

Does this sounds good to you guys ?

Dooop