HELP! What do I do with this 3.0L?

[911Freak]

I have a '81 911SC Euro, that had the original RoW engine replaced with a 930/07 when it was brought into the US in mid '85. Bummer....
Engine# 6402814
Originally came with #6312077 according to CoA

I bought it with 112K on it, compression is very good, needs tensioner upgrade, engine is noisy, NO broker head studs, passes Ca smog very clean. BUT seems low on power, hesitates over 5800 rpm, I added K&N filter, MSD
( ran like crap replaced with CDI) , Pop-Off, B&B muffler. Valves adj. regularly. Weltmeister strut brace, Yokohama AVS 100 ZR tyres, Polished Fuchs. Lite weight aluminum clutch (new).

Trans:915/62 #7310964. LSD?
originally came with: 915/62 #7312290. LSD? CoA

Should I spend the money and rebuil to stock?

I would like to rebuild to 3.2L by way of 98mm Bore X 70.4 stroke, w/965 cams, keep the CSI (can't afford MFI or PMO upgrade (Kid in College)
would have to save $$ for 6-9 months for this.

Should I just do the Carrera Tens upgrade?

I drive in PCA events, and hopefully DE events, haven't B/C worried about the noisy engine! Over 5800 rpm's engine stumbles, clicks and pops when shifting or down shifting, (decreased after valve adj)

So I drive in fear of hurting the engine...Starts smooth, idles smooth, my reputable Porsche mechanic hates the car b/c it's gray market?! Do I keep throwing money at this?

Experts please advise, I love this 911 and want to experience it's true nature worry free...

Thanks very much!!!


simplysmartmoney@yahoo.com

[911Freak]

Come on guys, anyone? What would you do if this was yours?

Any and ALL replies appriciated : )

Budget is aprox. $3500.00 USD

I have rebuilt many engines but this would be my 1st Porsche

Do I just "use it up?" as suggested by my mechanic, OR spend min $ for tensioner upgrade, OR dive in and build a 3.2??????

[Eagledriver]

Your running issues are much more likely to be fuel injection or ignition problems vs internal engine problems. If it doesn't smoke and has good compression drive it like it is and work on the fuel injection system. SC motors will run fine for several hundred thousand miles.

3500 dollars would buy a nice set of carbs or fund an EFI upgrade. Carbs won't pass smog however.

-Andy

[cowfly911]

I am new to the Porsches, but old to engines. If I were on your budget and had good compression, I would spend the money on the Carrera tens, getting the engine running correctly, and driving events. In a few years you have the skills required for the addional HP and the $$$ for the correct upgrade/rebuild.

Just my $0.02 worth...

[911Freak]

Thanks guys! That is my gut feeling too, but seeing all these SWEET rebuilds here I jones for a new engine!!!!

I will get the Tens upgrade, and start troubleshooting my CSI, Any ideas where to start or typical CSI issues to look for? I have all the books by Wayne and others... I guess starting there would be my best bet..

How would I find the alternative EFI upgrade? I see others mentioning a couple of Brands, but where do I get detailed info?

Thanks again!!

[cowfly911]

911Freak- Once again, I am new to the Porsche mark, but I too am considering changing the CIS system to something more modern. I have a couple of non-Porsche buddies using the Electromotive Tec3 systems and are pleased. Several Pelicans use the Bitz Racing Megasquirt system. You maybe more interested in the Bitz system since, at a glance, it seems be cheaper than the Electromotive system and you can use a modified CIS intake (see pic).


Image from www.bitzracing.com

Below are a couple of sites I discovered this week. Enjoy...

http://www.bitzracing.com/products/Complete_kit/index.html

http://www.clewett.com/

[911Freak]

Thanks Cowfly911!

This gets me pointed in the right direction!!

I will investigate both applications and post results and info ASAP

Thanks again guys!!

[fumanchu]

Freak-

Hi. Seeing you're in California you best stick to CIS if you want to drive your car on the street. Unless you have buddies in the smog industry there's no way you'll pass the visual with megasquirt or any major exhaust mods. Sounds like your motor is sound from your description, so why would you rebuild unless you know you have issues.

get in touch with understanding your FI and ignition systems and read alot of threads. Use the
"search" button and ask more questions when they arise. Pelican is a great resource and most are willing to give help.

I drive to Chico on business often, let me know if you need a second pair of eyes.
Good luck

Shawn

[911Freak]

Shawn, thanks... your right. The only reason I'de consider the rebuild is for more power. I know another guy in the North Bay who did the 3.0-3.2 upgrade, keeping his CIS, adding 98mm p/c and stock rod length 70.4mm, with exaust and ignition stuff he's getting 275hp at the rear wheels... Still pass' smog and gets decent gas mi.
So that's what I eventually want to do.

I am just worried about carnage with all the ticking and pops, and stock mech. Tens...

Are you active in the Sac PCA? I am member of the Shasta region but not many events, thinking of changing region b/c Sac is actually closer than Redding, and should have more DE events etc.

Thanks! Let me know next time your up in Chico, I'd take you up on that second set of eyes!

BTW if you are active in Sacramento PCA shoot me an email about who to contact at email add on my signature, that is if you don't mind.

[TimT]

How would I find the alternative EFI upgrade?

There are many EFI options from the basic megasquirt/SDS systems (Bitz uses megasquirt) which offer basic engine control, to other more robust systems...Simple is cheaper (relatively), better control is more expensive...

some EFI names you may want to research in no particular order:

Link
Autronic
Pectel
EFI
Megasquirt
Haltech
Electromotive
Motec
Bosch
DTA
Emerald
AEM
Accel
FAST
Holley
SDS

Its a big list!! MoTec, Bosch,EFI,Pectel = big bucks

Haltech,Electromotive, Autronic,DTA = medium bucks

SDS is a very good entry level system

I havent done a megasquirt yet, but maybe this winter I'll build my own and install on my racecar to see what its all about.

We have hands on experience with Electromotive,MoTec, Bosch, SDS, Link, Haltech and AEM Im sure im forgetting one though

Shameless plug we sell Haltech, like the hardware and software, and have never had any issues with the product

800+ hp, 9000 rpm, Haltech EFI

also the search feature is pretty handy

[911 tweaks]

TimT... I need more 800+hp engine sound clips...I would guess that was a turbo or twin turbo engine by the hisssssssssssssssssssssssssssssssss sound was so addicting! I just listened to the clip 15 times...

[TimT]

There are more videos on our website

Videos

[stevemfr]

Why does your mechanic hate gray market cars? Of all the cars that came into the country in the 80's, the 911 was one of the most easily modified - and kept near stock most closely. You may have an issue with the smog equipment, tho.

Does your car have a catalytic converter or was it brought in under exemption? If you have a cat (and your car was converted properly) you'll also have a pulse valve/ecu/o2 sensor to control the fuel mixture. If this is all add-on, it might not be so easy to solve your probs, but
I'd think first and foremost you need a new mechanic. $3500 will get you a long way towards fixing your probs, and from the sounds of it full stock power will suffice put a big grin on your face at the moment. Any mechanic worth his money should be able to work with what's there. I used to convert cars back then and am familiar with some of the more common fuel control ecu's used on K-Jet conversions - feel free to PM me if this become an issue.

[joetiii]

Do what they said.... tensioner upgrade, fix injection system.

Since you have to deal w/ smog I would rather look at changing out the final drive ratio to a 7.30:1 ratio. (Not sure how much for your trans). Its been said this change alone is similar to a 3.2 upgrade. third and least costly would be to lose weight. nuf said

[911Freak]

Stevemfr:
It did get the complete catalytic conversion, under the pass seat is the "brain", last time I had it in with the mechanic it was running really rough. He diagnosed that the Ox2 sensor was bad, R&R that, replaced the fuse under the seat and it ran way better... The mechanic was wondering why the system looked "different" I told him "hey it's a grey market car" but it's all there!

He's a purist, snobby bastard, but very good at what he does, and I keep going back to him because he did all the work on the car for the PO. Makes for a nice paper trail.

Since my last post here I've replaced the Fuel Injection manifold gaskets, that was where I tracked down a vacuum leak.. Idles very smooth and now only "pops" when downshifting.
I will do the Cam Tensioner update, and run it until if and when something goes bad, meanwhile I'll continue to save for the 3.2/EFI conversion....

I also contacted the PO and he gave me some more info he had found after the purchase: the trans was bebuilt with a 40% lsd diff, 1st/2nd syncros, etc.
So counting the miles I put on it the Trans has only 35K on it..

Joeiii:
best weight loss program for my SC Targa??
Pull out the rear seats, carpet, ?????
Best way to completely remove A/C system? The compressor is already out of the engine area, something in Fender well, condensor? Something under the Front pass footwell (looks like a finned cooler?) Trunk area too?
I already installed RS door panels
Thanks everyone, really!!

[joetiii]

Pull out the rear seats, carpet, .... yup and all the sound deadener underneath the carpets.

Best way to completely remove A/C system? Don't know if theres a best way but all the tubing to the condenser needs to go bye bye.
The compressor is already out of the engine area, something in Fender well, condensor?

The engine oil cooler is in the passenger front wheel well. Better leave that Something under the Front pass footwell (looks like a finned cooler?)

Trunk area too? Not sure if theres much there.

I already installed RS door panels. If no one is going to be using the back seats, you can get some fixed back light weight seats. That is good for a savings of 60+ lbs.

[jlmccauley]

Where do you get the fixed back light weight seats?

[911Freak]

Under the pass. footboard is a finned cooler looking thing, is this an a/c part? I'm talking about inside the car.

I understand the oil cooler in the "fender well" ( yep gonna leave that alone ! ) and I will remove the a/c dryer in the fender well and all hoses too...

I'm just a little curious about that finned cooler inside the pass. foot well.... It's got to be an a/c part, but I've check all my books and can't find a single reference to that part??
I did see that Porsche offered 2 a/c condensers, 1 front and 1 rear...I wonder if this is the case??

If I could only find out how to get my option codes!! No labels in the hood, door jamb area's, and the CofA was NO help, neither was calling PCNA..The said " sorry we can't issue you the cardex for your car, all info is on your CofA, it's not our policy to allow customers to have a copy of the cardex" well... alrighty then!

Anyways thanks Joetiii:
I will yank out the rear seats, heck one of the seat back hinges is broken anyways and being 6'4" no one is ever getting back there anyways!!

Someone told me once for every 4lbs removed you gain 1hp... probably BS but will save and weigh everything to see how much I can trim..

Thanks again!!

[stevemfr]

AC condenser in the car wouldn't make much sense as it would heat the interior... Take a pic.

As far as the fuel control ecu goes, is it OEM (typical silver Bosch ecu w/ a jetronic sticker)? If it is, you set the mixture at the FD just like a US 911. If not, you might want to check if there are potentiometers inside - there'll usually be 2: one foe the cold start mixture and one for the warm mixture. You might be running a little lean - many converted cars did. You'll need a wide-band o2 sensor and mixture guage to play w/this, tho, and a second o2 sensor bung ahead of the cat.

Another thing to check is if the cat is partially plugged. This is quite possible if you've had trouble w/the o2 sensor in the past. You might just want to book a dyno session and see what your rwhp is and if you're in the ballpark.

Good luck and keep us updated.

cheers,
Steve