SC engine upgrade questions...ones with hotrod SC's please respond...

[82SC]

Let's start an end all post for SC engine modifications

I have a tired SC and want to rebuild, and extract more power.
I know the whole transplant deal and I have taked to everyone under the sun about that so...no posts about transplants please.

I think there is just something very cool about building your own engine and running it in your car...very cool...and if the $$ are similar and the results are similar I would rather rebuild my own and say it is mine

So out with it folks...here are the things I know fo so far

1. add pistons and cylinders bringing displacement to 3.2, similar compression around 8.5-9.0:1 making a, what is refered to as a short stroke 3.2L

2. add 3.2L carrera crank (what are the details?) again making a 3.2L with similar compression as stock which is refered to as a long stroke 3.2L

3. Do both 1 and 2 to make 3.4L engine.

4. Cams depending on induction system can go with RS cams, 964 cams etc...what are the different personalities and outputs. What works with the CIS, MFI/Webers
Note: I want to build a motor that is ready for MFI...I can live with having no the optimal output when the rebuild is done, but once the emissions laws on my car get lifted it is going to MFI so I want it to be optimized for MFI down the road...so I am envisioning pistons with deep pockets but running milder cams till I get the new induction system

5. Induction system CIS vs MFI vs Webers vs ???
I know the CIS is not made for power...and the MFI are heard to be alot of fun....what are your experiences.

6. Porting and polishing...necessary? what are the advantages?

7. Heads
Some have gone to the 3.2 Carrera for the optimized combustion chamber...and ideas? what about the differences in port sizes between older and newer SC's? Can the new head be made to resemble the older model? What is the advantage here with larger ports?

8. Twin-plugging
necessary for higher compression pistons so that they can run on regular gas. But what about the costs of the distributor etc...is it worth the costs? I know someone mentioned a poormans way with switching guts from a 964...

9. Pistons
With any of the above pistons and cyl modifications what about the ability to go for a high compression ratio...does this nessitate twin plugging? what are the advantages. Also some of the newer pistons have the capacity for hotter cams. any thoughts on this?

10. Exhaust
the concensus seems to be early heat exhchangers/SSI and a dual in muffler. what about early sport muffler and aftermarket? I am running a 2 in 2 out dansk...sounds like a V8...people hate noise...I love it...

11. boring out cylinders
is something I have heard about but don't know much about at all.

12. trying to emulate the road going 3.0RS (RSR)
What is involved here? I think the engine case is similar to the 3.0 carrera engine...no? what parts would be involved

Please post your experiences and what you have done...pic are great, where you got parts, who did the rebuild any resources...also if not too personal ball park cost of mods would give readers a good idea about options

anyone who wants to add catagories let me know and I will edit this one.

This should be good for all those who ask this question and search the archives...I started one a while ago, but did into go into major detail about questions...lets try to keep the posting to the people who either have modified SC engines or the guys like Warren and John Walker with experience to keep the thread uncluttered...

Maybe if some one can write out a "money no object" combination, "track ready" combination, "street going" combination, "budget" combination...then things like torquey, highest hp, best middle of the road, personal favorite combination....etc...

Thanks

MJ

PS can you smell the SCWDP....muahahahahaha

EDIT: Well the post below says this is very open ended and I agree. Let's put some constraints:

money wise and parts wise it should be parts that are readily avalible or can be found with some leg work. No 935's!!! or laser welding additional cyl

And for money...that is hard...but something that maybe if you had a nice windfall or saved up money would could see yourself spending...if you want to spurge a little got ahead...

Emissions: there are guys who live in states without control and those who do...so I will leave this up to the responder...I am waiting for my 1982 chassis to be smog exempt in the next 5-8 years...

I would like to hear proven examples and not theoretical combinations...that was we can hear characteristics of the car in terms of torque, hp, torque range, peaky torque curve, etc...

[emcon5]

A related question, what is the most power the stock CIS system can support?
I would like to get higher HP from my car, but at the moment (and for the forseeable future) I am limited by California smog rules. Exhaust is fairly easy to swap out every 2 years, swapping CIS for Webers, not so easy.

Tom

[Bill Verburg]

Unfortunately your question is too open ended. The limiting factors are always at least 2 fold; legal restrictions and monetary restrictions. If there are no restrictions then build a 935 replica engine and be done with it. So, can you rephrase and include some more realistic constraints? Which should include, but not be limited to the above? Other considerations may include intended use, reliability requirements etc..

[Joe Bob]

Unless you keep an extra motor for the test man, you can't do much with the SC living in LA. Unless you are planning on an all track car....

SSI and 964 cams with the CIS is about all you can do......then you have to convince the tester that those nice looking heat exchangers are dual cats, crossing yer fingers that the adjustments you made last night will still pass.....

MY SC, barely passes w/o a smog pump....looks like it will go on to be legal when tested for the extra assurance....

[82SC]

I understand your question exactly. My problem is the answer is a moving target.
I believe that you want to have the satisfaction of rebuilding your own engine.
Good for you, nothing wrong with that. The problem is that it will be an ongoing
project with a completion date within the next 5, 7, 10 years. This is based on
CA antique tags and not having to deal with emissions.
For the foreseeable future you will have to live with CIS and cats.
Forgetting the engine size (3.2 vs 3.4) you mention changing cams. Will the new
cam work with CIS?
Port/polish or go with 3.2 heads. This may enable you to move more air but once
again will the CIS handle it?
Pistons and higher CR-anything over 10.25/10.5 and you should go to twin plugs.
The sad thing is the higher the CR the more power. You may be able to find a
twin plug dist, best guess is 1000-1200. The better solution is probably the
Electromotive style twin plug that will handle EFI, but EFI can only be added
after emissions goes away. Back to the moving target.
What is the target for your project? Is it a street motor, killer street motor,
race motor, all out most hp ever produced motor? Again, that ol' moving target.
Then to really confuse the picture you add in "if the $$'s are similar and the
results are similar" we can stop right there.
The $$'s cannot be similar. You've got too many options, 3.2 vs 3.4, stock CR
pistons vs hi comp pistons, stock cam vs hi po cam, stock heads vs port/polish
heads vs 3.2 heads etc, twin or single plug, the options are unlimited.
From experience, every time you change one thing it ends up making you change
something else. I'm not trying to bust your chops but am trying to point out
some of the problems.
It will be interesting to see what kind of answers you get to your questions.
Good luck with your project.
Don Wohlfarth

Here is an email I got (with a first line change... ) Don knows what I mean...see edit to 1st post...

[911nut]

Tom,
I've been told by people who know more about this stuff than I do that CIS can support up to 250 HP (that is K-Jetronic from '78 to '80 without the lambda sensor). On my own I've scoured the universe to find out if there was a way to enhance the stock K-Jetronic to improve airflow (and hence increase HP) into the engine. No joy. Cylinder displacement and exhaust backpressure appears to be the limiters to power improvement.

'82SC
I too have read Bruce Anderson's book and a lot of discussions of this board about hot rodding the SC motor (I've got an '82 SC also and had the same questions as you). My personal opinion leads me to believe that building a "high-output" SC motor looks like it will be very expensive relative to the horsepower gained. Per various discussions here on this website by people who are actually doing these things, seems like the guys who are dropping a 3.6 L engine into their cars are much better off when looking at $$/hp and emissions issues. However, I think, given the light weight of the SC, you would be happy with the way your car would feel with a 30 HP gain.

[pwd72s]

82SC...you don't have enough tickets yet?

[CamB]

THis is also well discussed on the SC RS and "help choosing a camshaft thread". Actually well discussed means I wrote a whole lot of probably incorrect stuff, but others had useful things to say

Both threads started by "cds72911".

Cam

[pwd72s]

"Both threads started by "cds72911".

Cam" Cam? Hmmmmmmmm Thanks!

[Doug Zielke]

For all the money your laundry list of heads, pistons, cams, etc would cost, there is no contest...You must SUPERCHARGE!

A nice Paxton setup as has been discussed here before is the best bang for the buck.

[RoninLB]

Nothing to post, except I take Bill Verburg's words seriously.

[mjc76]

I am going to be rebuilding my engine very shortly. Right now it is a 79' 3.0. I plan on twin plugging, P/C's to 3.2 with 10.5 compresion, Webber carbs, upgrade all head studs, and headers with 2 in 2 out sport muffler. I am hoping to get 300hp a the crank with this setup. Am I to optimistic.


MikeZ is the 25 year antique car exemption still in affect, and will I qualify in two years for that?



Thanks.

[emcon5]

Iris belongs to Randy Jones, (AKA RLJ) and her 281 HP "measurements" can be found here: http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=4483

As to the 25 year exemption for CA smog, there isn't. As I understand it, the law says 1973 or earlier, with a rolling 30 year exemption. Unless the law changes you won't be exempt from smog checks until 2009. It could be worse, I won't be exempt until 2012.

Tom

[Joe Bob]

30 year smog.....25 year for antique/vintage....different animal.

[emcon5]

Originally posted by mikez
30 year smog.....25 year for antique/vintage....different animal.

Really? What qualifies as "antique/vintage"?

[Yargk]

DITTO, I'll say my car is vintage. How can I do this? 3 more years !?!?!?!?!

[Joe Bob]

The reg says....25 years old and of historical interest...no definition of historical interest...so, whatever you can convince the drone at DMV it is.....I had some BYatch, tell me my 914/6 was not of historical interest...

I asked her to tell me what was....she gave me her best blank state employee stare.....I stared back....I'm better, I told her that unless she showed me a defenition in writng, MY car is of historical interest...because I SAID SO.

She took my money and said, well Sacramento decides anyways....stupid twit. Either way, I've seen them on other 914/6s so there is no problem....kind of a bad secret.

25 bucks for the plate and 2 bucks a year, no smog test and you are limited to driving to club events....kind of like going to AA meeting with a suspended license....there's allways one around someplace...

[speeder]

I, too, would like to get more power from my '82 SC. I plan on resealing it this winter,(rings, valves, etc.), 964 cams and SSI's+ lighten it some,(RUF fg bumpers).

The problem with doing more than that is that it is an absolute "law of no return" dilemna. My car is a pretty nice one, never smashed coupe w/ 110k miles, and I am also sinking $ into stereo, suspension,etc. At some point I could just buy a better, (and faster), 911. If I stick to plan, I should be able to get most if not all investment back if I sell to upgrade. Why do you want to keep that particular car forever? I like my car, but SC's are not that special, (insert flames here).

Sounds like you have Porsche OCD even worse than me, but that's what we Pelicanheads are all about.

[Bill Verburg]

Didn't we go through this all before?

http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=4620

[RoninLB]

250 hp - 300 hp Sounds like fun. At what point does "dowel pinning" and serious crank mods become coffee conversation in the SC??