How can I upgrade my 3.0 engine
 

What can I do to gain some HP on this non computerized engine. I already did an exhaust but I do not know what else I can do that is relatively easy without doing a rebuild with a cam, etc. Any suggestions?

carbs

This one's easy. Follow the link and don't look back
http://forums.pelicanparts.com/porsche-911-technical-forum/645203-finally-registered-pelican-introduction.html

EFI, Bitz kit or TBI's for more horse power with fuel efficiency and tuning ability.
Add EDIS as well. I'm headed that way this fall.

No cis
 

I just went through all of this. CIS sucks and is too temperamental. Go with aN EFI setup or carbs. Drove a buddies car with webers and a secret cam grind....very nice and responsive.

HP to weight ratio... Put it on a diet. Multiple threads here for getting your car slim and trim. ;)

Throwing carbs on it isn't really an "easy" modification.

Porsche already did the easy stuff, unfortunately. These cars aren't like some american iron, where hp may be found a little easier.

On my SC I had put 964 grind cams, SSI + dansk sport muffler, and increased the advance a little over spec. I also took some weight out of it - not too crazy. You can follow the link in my sig describing the car. Eventually it was too slow and uncomfortable, so I bought a 993. ;)

G

You really need to define what you are looking for. That new screwbaru will give you a run for your money...

SSI's and a good exhaust are good for what, 15 HP increase, EFI is touted at 25 HP increase, same with carbs, so with both you may gain 35 to 40 hp.
That takes you from 185 to 215 HP in a fairly heavy vehicle.
Do both and lighten it up and you'll be rockin....
Or, stick a 3.6 in it and go....

Do cars get smogged in NY, or is that only done in California?

No smog here for now but you never know.

SSI's and a free flowing muffler will really help.

^this

my 83 has carbs, 964 cams and euro compression... none of that gave me a seat of the pants improvement as significant as simply doing the SSI's...

Im a brooklyn native , hope you dont park that beauty on the street :)

another perspective.
I have other cars with huge HP, they are fun but I can't really 'drive' them without breaking multiple laws unless on a track.
My '83 sc makes about 200 hp and I I've lightened it up considerably. It is nimble and I can flog the hell out of it and enjoy it. I can use the cars rpm range and it is much more street fun than some of my other cars with more than twice the HP.
Get a few more HP, lighten it up and drive the hell out of it.

Excellent point and one of many reasons I chose a torsion bar 911 as a fun car.
Now I'm just plain addicted.

Dean

Thanks, and one of the many things that a lot of people do not understand about engines is, until you can get the exhaust out in an effecient fashion, it does not matter what you do with carbs, ignition and so on, the inability to get the exhaust out will always hold you back.

Second thing is that until the suspension and brakes can handle every last horse power you have on tap, then you are going to have a substandard car.

Upgrade your brakes first, they are the main safety item on the car. Then do the suspension, re-doing the bushings, torsion bars, sway bars and so on to make the car really handle with what power you have now, and expect to have in the future. Then and only then focus on the engine and the first thing to do with the engine is upgrade the exhaust!

Joe A

Great Advice.

This is how I'm personaly going about my car. No sense in engine improvement untill suspension and brakes are up to snuff. And yes exhaust is key to realize full potentional of engine mods.

Dean

+2 Brakes were my single greatest upgrade.

Agreed, I have always been in the camp where the thoughts of "cat back" exhaust upgrades were kinda voodoo in that they may add a little hp at the top and little to none and maybe even a loss at the bottom.
Obviously this stuff varies from car to car but in the case of the 3.0 I believe the stock system is less than ideal. I've "upgraded" exhausts on lots of different cars and never had such a drastic change as in my 911.

Vinny,

The newer your car is, the worse the exhaust is in terms of performance. Thats why the SSI's systems are a direct copy of the early Porsche factory exhaust system. It did ONE thing, get the exhaust out of the engine.

Later model exhausts had to deal with smog, noise and last forever, so Porsche changed things and it was not always for the good.

The stock 3.0 SC HE primaries are too short and of unequal lengths, offering very little, if not 0 scavenging effect. The SSI's and early factory HE have primaries of longer and equal length and merge at a location that optimizes scavenging. That's why they make power throughout the rpm range and not just in the upper end.

This trend was finally reversed on the 993, BTW.

G

Not to sidetrack this thread (engine mods), but when you guys speak of brake upgrades, you are talking about getting the stock system up to top shape? That makes sense. What does not make sense is to upgrade to turbo brakes or similar. The stock brake systems on the 911 are very capable and a 200 hp SC with stock brakes will be no problem unless you track the car in a hot climate.

G

Looking at it from a different angle, making sure you engine is running as well as it can will probably net you a few ponies. CIS can have air leaks, distributors bushings and wires get tired. Warmup regulators can control the fuel in a non-optimal way, etc.

I found the most satisfying improvements were fixing the bugs that made it run less than perfect. It's a pretty cool car as-is.

I am pretty sure you can advance the distributor a wee bit for better response but I have not done this. If you search there is info on it.

Yes and no. The above advise is fine if you are going to stick with the 3 liter engine in the car forever.

However if you are looking at doing a 3.2 or 3.6 upgrade or other HP mods, now would be the time to look ahead and do it right one time.

I agree that a 3.6 would warrant a brake upgrade. A 3.2 together with chassis lightning will not need an upgrade. If you like to fiddle with the brakes anyway, then the carrera brakes are a good and cheap upgrade, albeit only thicker rotors with matching thicker calipers.

The turbo brake upgrade is $$$. It was one reason I pulled the plug on my SC - blowing $3k on brakes looked like a good opportunity to sell the SC and put the $3k towards a 993 (which came with big reds ;))

G

I have 930 brakes now. Seemed like a good choice to me after the amount of other modifications I did. Safety and such. But yea, I can't see doing it if you're not chasing a lot of power.

That is great info. I always thought that the SC exhaust was "tuned". Maybe some of those advertisements that say "SC exhaust are as good as headers" had me confused. The ads probably are referencing the high RPM output only.

78 should have big valve heads
 

IMO Remember to save all of the SMOG equipment you remove because THE MAN will be sniffing you tailpipe sooner or later. Kalifornia has it 76 up so 74 back is an E-Ticket here. Also Clean stock early SC cars are climbing in value these days. A 78 should have the big valve heads and that is a good thing for you. Static CR(compression ratio) is decent on a 78 too. IMHO start low buck with an SSI, muffler of your choice, & re-degree the stock SC cams. If the SSI & muffler is out of budget or too much hassle look at the by-pass tube & maybe a muffler. Pelican has the AIR Block Off Plugs. Your CIS is not evil and the 964 cams(and reground rockers) are probably the upper limit to avoid low RPM/idle issues backing up thru the intake valves with CIS. My techo junkie neighbor with the WORKS MINI is always asking if I want to sell the old 911 hot rod with a Euro 3.0 & SSI. Clean looking SC. Make yourself happy:) and enjoy the ride.:cool: