performance upgrades for a 911sc 3.0

[Gunter]

germaniac:
Forget the air filter as a HP-gain.
All these 3.0 liter upgrades have been discussed repeatedly here, do more search.
To gain ~40 HP, are you willing to spend $5000.-?
That's how much it is, parts and labour, to do the 964-cams, new P/C's, SSI's & muffler etc.
Once the engine is opened, all kinds of costs will appear like the heads need to be done and what about the head studs? It's silly to open the engine and not do the heads and studs.

If you budget only a couple thou, you'll get the SSI's & muffler plus the 964-cams and you'll need to do the work yourself.

So, how much do you want to spend?

[low944]

Has anyone heard of the CIS trick to increase fuel mix at lower to mid rpms? I heard that Porsche held back on the fuel until wide open throttle?

[Paulporsche]

JW,

Tell us to what you are referring.

[low944]

I dont know, that is why I am asking! Its some wiring trick to the cis system that starts the power band increase alot sooner than normal. A local porsche shop owner told me that he could do it for an hours labor charge. It sounded like something that someone could do themselves. I may start another thread to see if anyone has heard of it...

[mack6820]

I would pay the guy for an hour just to see what he did? Then share his secret to us!!!!!

[low944]

Originally Posted by mack6820

I would pay the guy for an hour just to see what he did? Then share his secret to us!!!!!

I may just do that!

[911 tweaks]

please post the findings either way on this thread as I am subscribed to this and I don't want to miss what you find if you go and post ~ start a new thread!
Thanks !!
Bob

[autobonrun]

[QUOTE=JR_NYC;3796838]Does this mean SSIs and e.g. an M&K or Monty exhaust will give an SC 17-22 hp more?[/QUOTE

I feel that 17 HP is definitely achievable going with SSI exchangers. I ran a few before and after tests using a G-tech Pro. See the link (it's been a few years) but the results are still valid.

Separately I had my SC dynoed after installing the SSI's. If your engine is in good shape, you will definitely feel the improvement. My car has 211k miles and has never run stronger. It really perked up with the SSI's. The SC benefits from the SSI's balanced headers. Very little else you can do without going into the engine itself.

Performance Test done - SSI vs Stock SC

[t951]

what about msd?

[ingimar]

what size header 1 5/8 ID=41mm engine 3.0 liter

[Dmitry at Pelican Parts]

If anyone is looking for any Performance related upgrades, please take a look at the link below. We're happy to answer any questions about the products.

Performance Brake Pads, Shocks and Springs, Air Filters and Exhausts - Pelican Parts


-Dmitry

[75 911s]

Originally Posted by low944

I dont know, that is why I am asking! Its some wiring trick to the cis system that starts the power band increase alot sooner than normal. A local porsche shop owner told me that he could do it for an hours labor charge. It sounded like something that someone could do themselves. I may start another thread to see if anyone has heard of it...

I remember reading about this. I think some US and Cali cars had a brown wire at the DME you could disconnect - might have been the 3.2. Search brown wire dme

Edit found this:
Those brown wires are for California emissions purposes only; they would be connected, and the DME would use a different map. Unfortunately, that map also reduces power somewhat, so it's best to leave the wires tapes up and unused. If you check out Steve Wong's website (911chips.com) he has a nice explanation about all of this.

[Flojo]

not exactly speaking of performanceupgrades from view of a race car but here's what I did to my 79 SC:

1. the obvious: weight reduction
- cleared the trunk (no carpet, no spare tire, no everything)
- switched to smaller/lighter battery
- deleted all of the AC stuff
- lightweight parcel shelf
- removed rear seat flaps (who needs theese anyway?)
- deleted radio & speakers (we are in the bluetooth / UE-boom age now, if needed)

2. injection:
- full tear down and refurbishment with lotsa cleaning and seals
- new injectors
- polished the inside of the 6 airpipes (smoother airflow)
- carrera fuel pump

3. ignition
- permatune 2.0 version
- rebuilt distributor
- new wires und plugs

4. exhaust
- SSI
- Dansk 952 sport muffler

at end I let the car be corner balanced (as bilstein Nürburgring went in there too) and I let the engine be regulated.

it revs like a champ, and running 220+ kmh is of no worry.

but @all: don't forget the brakes!! they should be better than good already before tuning.
at least attend them simultaneously.

[G450X]

Along with the upgrades previously mentioned, I will add a few more to consider.

You did not mention if your 3.0 is an early U.S. ('78/'79) or euro version. These 3.0's would be a better base engine due to the higher flow CIS & heads. Upgrading the heads and CIS is costly if it is a later U.S. spec 3.0.

I would also suggest (if your budget allows) Max Moritz Mahle P&C's for a slight displacement bump. They are hard to source used (and are costly new), but with the appreciation shown by the air cooled models, I feel they are a reasonable upgrade if a rebuild is due.

I am in the same boat with my '82 SC. My first mods were SSI's and and an M&K muffler, and they added a nice performance gain. I have been collecting parts for several years to offset the pain of my pending rebuild. My plan is to add early high flow CIS and heads, 964 cams, and Max Moritz P&C's (all sourced used) to add more power.

Also, consider removing weight (the Lotus mantra) to add a performance bump.

[kent olsen]

Trust me it's a lot cheaper to remove weight than add horsepower. I removed 150 lbs with a little fiberglass front and rear, lighter seats, lightened door panels, removed one of two batteries, M&K muffler (10 lbs vs 30 lbs) and more. All that compared to $12,000 when it came to the engine. All this on my 72T 3.0L.