Upgrading a '71 T to S specs

[bhensarl]

I'm thinking about upgrading my T to S specs (and most importantly horsepower!). What are my options? How involved, exactly, would that upgrade be? I know that the S engine has higher compression and that the fuel injection is different? I'm no gearhead. What am I looking at?
Thanks.
Brian Hensarling

[GIBSON]

Brian, it certainly can be done. Your's is the last of the carburated T engines so you don't have the mechanical injection you'd need to go to full original S specs. You could

1. Use your engine, upgrade to S pistons and cylinders, heads
with correct valve sizes, S cams and use Weber carbs (40 IDS)
and have a very nice engine. With this conversion you can
use your existing fuel system including the pump.

2. Upgrade your engine to S specs and find an original
S mechanical injection system. You'd have to change your
fuel pump, lines etc. More expensive than above option
but closer to the real S.

3. Find a later original S motor and install it with all the right
pieces already installed.

If your engine is tired and ready for a rebuild, why not go to S specs, the carburated upgrade of your engine is a nice way to go.

[DByers]

As Gibson mentioned it can be done, its just a matter of $. I also believe the crank was different for the S to allow for higher RPM.
You may not need to ditch the Zeniths either if you still have them as there are places that you can still get what you need to rebuild them. Mine still work great.
The other consideration to look at is what will you be using the engine for? Yes the S has more HP but you dont see that until the upper RPM range, which might not be the best for street driving.
The T I think actually had a faster 0-60 time do the torque curve.
Where are you located? You might check around your local area (PCA) and see if other early cars exsist and maybe get a feel for what the differences are. (if you are close to me, my 71 is good for a test drive)
Im sure the trans plant guys will chime in soon. For the cost of what you are looking to do you could spend a little more and do a trans plant if HP is what you are looking for.
I opted to keep my 2.2 when I did a rebuild and dont regret it one bit.

[sammygon1]

What about going to solex cams, wouldn't you have more power on the bottom and top end? How much power do solex cams produce as compared to S cams. One of the recommended engines in Wayne's book is a 2.2 with S heads and solex cams.

[bhensarl]

Wow, so much info and so quick! I love this board!
Really what I was looking for was a bit more punch. I'm not a racer or anything, so daily drivability is my main goal. Just looking for a little more Porsche behind that gas pedal. What are the main differences, performance and mechanical, between the Zeniths and the Webers? I'm only 22, fresh out of college with student loans breathing down my neck, so $$$ are definitely a bit tight. You guys got any ideas on what might be my best choices for bang for my buck? I was thinking the upgrade to S would be the way to go, but if there are better ways to squeeze a bit more quickness out of her, I'm all ears. I really appreciate the quick responses, and as always I humbly bask in the glow of enlightened Porschephiles!

[DByers]

Well just a thought and a route I might take is to have leak down and compression check done (how many mile on the engine?). When was the last time the carbs and valves were adjusted? Have that done also if you cant remember or dont know. A valve, carb adjust and an overall tune up can bring back some lost power. Once you have this info you can judge how much time is left in that 2.2 you have and really be able to think long term.
I know it may not sound right but also your suspension has seen a few miles and may need to be refreshed. You would be suprised how much lighter and better your T will handle with some fresh suspension.
Exhaust is also a place where a few ponys can be had. SSIs with sport exhuast is good for a few HP and $$.
Just thinking out load here, excuse me if I am off base.

[Early_S_Man]

Brian,

You don't say whether or not the 911 is your only daily driver ... but that will place certain constraints on the practicality of an upgrade. Additional hp raises the need for an external front oil cooler, among other things, for long-term reliability!

One option is to bore your existing cylinders to 85.0 mm and get 9.5:1 JE pistons with valve reliefs for radical cams like 'S' or GE-60's, and for low-cost you can retain your carbs and only lose 10 hp or so ... 170 - 175 hp is feasible, and usable with 91 octane gas! A 7000 rpm redline is realistic with your crankshaft. Porting your existing heads is optional ... bottom end and mid-range torque would be better by leaving the ports alone and running the hotter cams. You would only lose 5 -10 hp at the top end. All 2.2 thru 2.7 engines use the same basic head casting and valve sizes -- 46 mm intakes and 40 mm exhaust. A good compromise would be to open your ports to 33 mm - 34 mm, up from existing 30 mm, and a bit under the 'S' and 'RS' ports of 36 mm.

At one time the factory offered rallye engines based on 'T' heads, but with the carburetion and cams of the 'S' engine -- only 10 hp less than the 'S' engine of the day! The bottom-end torque was said to be improved, but I don't have the exact specs.

The first three books you need are Bruce Anderson's Porsche 911 Performance Handbook and Wayne's two books from this website.

[targa911S]

I believe the connecting rods were different in the S motor also. My .02 would be to find an S motor and be done with it. The S motor especially 2.2 is a "peaky" engine and not very friendly cold, at low RPM, and in traffic. They start to breath at about 4200 RPM and rip to 7200. I find myself driving in 3rd and 4th gear a lot. The E cams are a lot more driveable and make their power lower in the band. S cars are crabby SOB's

[MotoSook]

Having been a college grad ..gawd it doesn't seem that long ago!..I say don't do anything yet. Just get the car tuned and enjoy it. Once you start tearing into it, your college loans will be coming, and then you'll be selling the CD's you bought in college to make the loan payments...geez how many CD's did I buy?!...

If you want to really enjoy the car, take it to the track. It will cost less (initially) than an engine. You'll feel like a superstar and on the streets you won't have to have gobs of power to race the Mustangs...'cuse you'll know better than to street race..you'll feel like "Cool Breeze" just going 30 MPH, 'cuse you'll really know what it's like to go fast.

Man I like to preach...just don't be in the car with me when the punks in the hood ride up to me and ask for a race

No, really, join the PCA and got to a few Driver's Educations per year until you are really ready to start dumping money into Porsching.

With DE's you'll discover the limits of your ability and your car while having a great time. You'll meet good people and learn a lot from them. I think that'll be more beneficial to you than a new engine.

[bhensarl]

Okay, let me fill in some blanks...
-The 71 T is a daily driver with 116000 miles on it.
-All original, no rebuilds or mods.
-I'm definitely not looking for "crabby" or "peaky" performance, I just wanted to add a bit of zip to my T if possible without changing the power band or many other lovable characteristics!
My next step is definitely picking up those three books. I really appreciate everyone's suggestions! Thanks for helping out a young Porsche lover!

[Randy Webb]

I would keep carbs on it -- at least for a while.

Don't the T's have different struts? You could put S type struts on it and use the Al S calipers, or just replace the entire suspension with one from a Carrera -- that would save some wt. in the rear. If the Carrera calipers aren't good enough for you, then put the (44T calipers on (see Bill V for more info).

There is also the matter of guages, trim, etc.

For the engine I would not stop at S specs -- I'd go to RS with a 2.7 or even bigger. Why make a T into an S when you can make it into something a lot better -- more powerful and lighter.

[dd74]

I like Souk's idea. Save the bucks; pay off life. Buy stocks, and from all I've experienced, T's spank S's in everything but all-out high RPM driving.

[jim72911t]

umm, what Souk said

-Jim

[Zeke]

hensarl, if you crack open that engine, be prepared to spend gabs of money. Auther Wayne and partner at Pelican says the minimum expenditure is $6000 with you doing the assembly and reinstall of the engine. Many 3.0's go for half of that. And I mean ones that are not tired. A 2.2 S motor is rated at 180 HP. The 3.0 is in that neighborhood with smooth, reliable performance. That leaves you the rest of the money for other improvements to the car. All in all, you'd have more car that way rather than chasing the S mystic. The 2.7 RS advice is good if you have the coin.

[pwd72s]

Originally posted by dd74
I like Souk's idea. Save the bucks; pay off life. Buy stocks, and from all I've experienced, T's spank S's in everything but all-out high RPM driving.

LOL here...I remember driving to the '71 Pea-raid. I was in my '70 911T, pretty new then. A guy from Coos Bay, OR, also in a 1970, pulled to the left to pass...we were rolling about 70 then. He blew by me like I was riding a bike, depite me having my foot to the floor. He was driving a 911S. Bottom line? Stock equipment? Nope...T's don't "spank" S's...and I don't care where you care to put the revs range.

[Randy Webb]

Yes, it's all about coin. Why don't you think about the advantages and disadvantages of immediate (relatively speaking) gratification, then post a $$ figure and what direction you are interested in going (outlaw, concours, daily drinker -- I mean driver, etc.). We are all willing to help you spend your money.

[dd74]

Originally posted by pwd72s
LOL here...I remember driving to the '71 Pea-raid. I was in my '70 911T, pretty new then. A guy from Coos Bay, OR, also in a 1970, pulled to the left to pass...we were rolling about 70 then. He blew by me like I was riding a bike, depite me having my foot to the floor. He was driving a 911S. Bottom line? Stock equipment? Nope...T's don't "spank" S's...and I don't care where you care to put the revs range.

70 in what gear? Were you near the top of the rev range? Didn't I mention something about all-out high RPM driving is where the T won't take an S?

Sounds like you found out first hand what I've already said when this guy waved to you.

[pjv911]

Brian, where are you located ? I may have a deal you cant refuse. Im doing a motor swap in a 1969 T and it has a 2.2 T motor that was (according to the past owner) just fully overhauled and converted to S specs. The engine is still in the car and runs like a scalded dog. Its just as powerful as my 2.7 motor and sounds better as well. I will be selling the motor in about 1 month. It is in the car ready to be test driven. You could see what it would feel like before you buy it. I would likely want your old motor as a partial payment. I will be looking to get somewhere in the neighborhood of $2200.00(or $1600.00 with your old motor) for the engine without carbs , but with recently new 3 into one exhangers and a sweet sounding aftermarket muffler as well as the fan/alt and oil cooler. I could also do the swap for you for around $500.00 if its during the winter months. The motor is clean, burns "NO" oil and does not leak any oil (yet). PM me if interested.

Kurt

[pjv911]

Oh and brian, im also open to all trades.

Kurt Williams

[Zeke]

Jeez, what a deal. I'd be on his doorstep, but I'm on the West Coast. That hurts so bad I have to bite my tongue.

Edit: That is if it really is an S spec engine complete with aluminum cylinders and passes leak down with excellent figures.