The ultimate 3.0L SC conversion thread?

[rdane]

I have been searching the forum for several days and have read a half dozen threads including one with a similar title for 2001.

I would like to get some input on rebuilding a streetable hot rod on 3.0L SC case with:

1st no worries about emissions/ no testing required
2nd max durability
3rd as a street/track car
4th the most amount of power you can obtain and still have the above (how about 275/300 hp as the goal)
5th costs must stay under 15K$ so no whiz bang engine management systems
6th no motor swaps to 3.2 or 3.6
But how about a realistic/actual cost for the 3.6 swap (which seems like 15K if I am reading right)

For the poor folk in California/WA and the late SC.....feel free to add what you think will pass emissions.

In short a even prettier Iris

[Vipergrün]

Hmmm, check out the 911 Performance Handbook.

My dream would build one up to SC/RS spec, but I do not recall all of the details. It was 300bhp.

One thing which will most likely come into play is higher compression, so make sure you either have the high octane fuel available, or twin-plug it.

Sounds like a really fun project. Can I borrow 15K

[Vipergrün]

Here are a couple more details on the SC/RS motor.

"In Autumn 1983, Porsche presents the 911 SC/RS for motor racing. The engine of the small series originates from the 911 SC. Improved performance is achieved by the mechanical ball fuel injection, increased compression, the cylinder heads from the 935 and forged pistons."

Sounds expensive!

[Wayne 962]

The only thing is JE Pistons and 964 cams - anything else will throw emissions (or price) out the window...

-Wayne

[emcon5]

Originally posted by rdane
1st no worries on emissions.

This could mean 2 very different things.

Do you mean you don't want to worry about passing emissions every year, so no carbs/hot cams, or do you mean that you have no emission testing where you live, so passing emissions is not something you need to worry about?

Tom

[rdane]

"No worries", as in no testing required.

Wayne are you saying it can't be done for $15,000!!?

I have a quote from Andial, who I thought was the most expensive shop around, starting at 12K$ for a 3.7 conversion up to 23k$ and 290 hp on that same set up with heat exchangers and a sport muffler (muffler alone is $1000 I was thinking "we" could do better.

Here is RLJ's Iris specs.

1983 911 SC (bottom end)
3.2 liter(98x70.4),281 HP and 244 ft/lbs torque @ 6100 RPM's,8000 RPM red line, 10.2:1 J-E pistons, Web Cam grind #120-104, 3.2 Carrera heads with high RPM springs and retainers, dual plug, PMO 46mm carbs on tall manifolds,964 distributor, ARP rod bolts,Elverude aluminuim flywheel with Sach aluminuim pressure plate, Carrera pressure fed tens, twin MSD 6 AL ignition boxes, 930 lower valve covers, SSI heat exchangers.

I have talked to Randy and it sounds like an awesome engine but with a few problems still being ironed out. How about doing a similar project here so that has no problems and the base specs are extremely reliable as well as powerful. So what can be done with the '79 bottom end within the constraints of what I would like to see in the finshed engine? Call it the "ultimate Pelican SC rebuild". Come on guys...Wayne.....there has to be something out there that has been missed that can be a "canned" project. How hard can a 3.7 CIS be? If the owner of Andail decided to run a big bore CIS I suspect there are a lot of us that might opt for that solution than go begging for a used 3.6, if no matter what you do it is +/-15K.

I have read Anderson's and Wayne's new book several times and have talked with half a dozen motor builders. What the builders are saying would seem to out date the published material. That wouldn't be a surprise as it takes a awhile to get things published.

[widebody911]

Forgive me if this sounds pedantic, but if you're looking to drop a solid 5 figures on an engine conversion, why are you so enamoured with the 3.0L as a base?

[rdane]

Good question Thom.

First I see the 3.6 conversions costing 15K at least. Second those engines and any othe swap is still a gamble on a used engine.

$8K for a well done 3.0L rebuild but the labor cost doesn't go up if you add new P&C for a "known" end product.

My impression is the engine swap has been the "easy" thing to do it but not any less expensive or a better engine if rebuilt properly.

I just haven't seen the facts saying the 3.6 swap is less expensive, less of a hassle getting it plumbed correctly or better in the end. Easy enough for me to be wrong in that assumption though.

IIRC remember BBII is running 260hp, right? Jack? Your 3.6 Thom? I a looking for +/- 300. It's only money right?
What did your 3.6 conversion cost when you were done?
If dbl the 8K$ for a 3.L rebuild will get me 300HP I would seriously think about it. I have been told 16K will indeed get you close to 300HP so I am asking questions.

Car pins my wife to the seat now so she is asking the same question, "why more?"

Where is the SCWDP membership when you need them? You guys are going to be doing this some day soon yourselves!

[turbo6bar]

My uneducated vote is for a turbocharger. I think you could do a mild build, prepared for a turbocharger, and be able to stay under $10k, depending on how much you farm out. HP would be great, and torque would be awesome. Basically, build a bulletproof 3.0, add a good exhaust manifold and EFI (Megasquirt, SDS, Haltech, Autronic), and 275HP should be a walk in the park. However, I do like your call for more displacement.

Well, that's my dream for today.

Jurgen

[dd74]

rdane - Thom has a point. For $23K, (yeow!), you can get yourself a 964.

But who wants to do that?

Seriously, a "good" 3.6 conversion and all the anemities, such as a fortified gearbox, exhaust, and maybe even an upgrade in suspension could be had.

Not that I'm a great purveyor of the 3.6 conversion, though it is a nice set up to consider.

As for $23K for a 3.2 setup? Well, 3.7 liters out of a 3.2 sounds real "iffy" to me. Without getting too technical, there is only so much these engines can take and still be manageable/reliable. They're built pretty close to their tolerance levels from the factory.

Also, where on Earth will you use all of it, except on a track. Is this going to be a track car? You'll ruin a "hot set up" engine on city streets. I know from having a couple of them in the past. If you live in L.A., forget about it.

If I were you, I'd stick with 3.4 at the most. You'll still be looking at about $10K, and come out on the low side of the cost of a 3.6 conversion, not to mention the weight penalty involved with a 3.6. In fact, I couldn't see a 3.6 conversion in anything other than a light early 911 - there is a lot of #s with all that additional plumbing.

In addition to the $10K, maybe $3.5K more will net you a nice suspension set up, some good seats, maybe some f/g parts to lighten everything up. An additional 3K will get you a better transmission set up, too.

At that point, you'll have a real fast car. I don't know about its reliability on the street, but anywhere else where the roads are clear, it'll be a rocket.

Here's the math as I see it:
$10K for a 3.4
$3.5K for suspension, seats, f/g parts, et al
$3K for trans work.

That's $16.5.

I'm not including brakes, which you'll need for track work. And the dreaded labor to put it together, which is a whole different ball game unless you're D-ingIY.

By that time, you're at least spending $20K; definite 3.6 territory, though you don't want to talk about such a conversion, right?

Another options could be to sell the 3.0 and start with a 3.2 base. At least you'll save some money on a Carrera crank, and already have the EFI. That's be $3.5-$4K saved there. Of course there are the rods and valve guides to consider with the 3.2, so maybe you can forget a grand or so in the $3.5-4K savings.

Now of course you could sell everything, add it to the $23K, and buy yourself a pristine late-80s, early-90s turbo, and give the 3.6s a run for their money.

Personally, I'd take all the money and put it in Halliburton and Bechtel. They'll be running the Middle East oil supply in about a year...

But what fun is that?

[RANDY P]

Originally posted by rdane
IFor the poor folk in California/WA and the late SC.....feel free to add what you think will pass emissions.

If memory serves me correct you should be coming up on exemption soon. As long as you're not gonna move anytime like to CA soon it shouldn't be an issue.

If all else fails, there's always that PO box in Olympia!

This is going to be a good thread...

rjp

[rdane]

"Thom has a point. For $23K, (yeow!), you can get yourself a 964."

DD that is my point 23K is rediculious for a new engine in these cars.

"Here's the math as I see it:
$10K for a 3.4
$3.5K for suspension, seats, f/g parts, et al
$3K for trans work."

I have already done it all, including brakes. Forget the "add ons" let's talk engines. Seems any old fool (like myself) can figure out and find a guy to do the rest...I did and I am more than happy. But the 911 engine is still the "knowledge held by the spirit walkers".

Come on, a nice engine, better than a simple 3.2 conversion with a cam......for under 15K. Does everyone just give up and drop in a used 3.6?


ps, Randy I have indeed passed my last required emissions test

[CamB]

1st no worries on emissions.
2nd max durability
3rd as a street/track car
4th the most amount of power you can obtain and still have the above (how about 275/300 hp as the goal)
5th costs must stay under 15K$ so no whiz bang engine management systems
6th no motor swaps to 3.2 or 3.6

Is it $15k for parts or including the rebuild? Assuming the latter, and taking your $8k as the "rebuild" figure, leaves $7k for parts. Pistons and cylinders will be up to $3k, leaves $4k. Camshafts - I'm not sure? $600? SSIs and muffler will chew up another $1200 or so. Leaves only $2k, and you haven't addressed fuel delivery...

Fuel delivery constrains #1 above. As I understand your smog laws, the
CIS has to stay? So you are best to spend the rest of the $$$ on finding a 3.2 crank and (if I remember this right) getting the case altered so you can use 100mm p&c rather than 98mm. This will give a 3.5.

My completely uneducated guess is that with CIS friendly cams you will get 17% increase from displacement, plus SSIs and the cam (maybe 20hp together). Taking the high compression SC engine - 204hp x 1.17 + 20 = 260hp (call it 235hp at the wheels). Note this is basically Bruce Andersons maths too, so I guess I plagiarised it!!!! I've got no idea if it is easy or hard to make CIS work with this.

I would disbelieve any higher estimate than this. I've got a similar engine to Randy's Iris, but with slightly less camshaft (I have S cams) but the benefit of fancy EMS. I have ~270hp @6200 (245hp at the wheels).

In summary, unless you rebuild yourself I can't see how 2750-300hp is achieveable, even ignoring the requirement for emission friendliness.

I wonder about reliability. I want 60k miles plus from my engine. 100k miles would make me happy. It is basically a twin plug, high compression S engine.

[rdane]

270hp would be good too :lol:

Leave off the cost figures for the SSI and muffler......most will have those already if they are thinking along the same lines as I am.

Now we are getting some where, "the benefit of fancy EMS", tell me more please?

8K in labor.....3.5K for P&C and cam. So we are at 11.5. Where should the other 3.5K go? Carbs, EMS?

This thread could also easily end up making the definative statement that a 3.6 transpalnt as being the best idea.

Wayne's book says the Andail 3.7 CIS hit something like 300hp.

[CamB]

I haven't read Waynes book! (sorry Wayne, I'm cheap at the moment).

$3.5k is pretty tight for what you need, although it would probably go close with carbs. I guess if you got second hand Webers which didn''t need a rebuild then it would happen. By then, you are more or less replicating the engine Wayne posted about a couple of days ago for his 914/6.

EMS is expensive. You need the throttle bodies, fuel rail, injectors, sensors and computer itself, then dyno time. I've got an older MoTeC with a set of MFI throttle bodies modified for 944 injectors (the injectors cost about $750 alone...).

Looking at my guess for the 3.5 vs what I got from 3.2, the displacement looks like easy money. I have a feeling it is actually pretty costly though...

You need someone to chime in who has been there done that. All I've done is been there, paid for that!! I asked a lot of questions, but didn't make it myself. It cost, um, lots. Its pretty cool though - the engine comes on cam very hard at 5 and bit k revs, with none of the negative of lack of torque at low revs.

(edit) Andial's 300hp? I guess maybe. That's what? - 81hp/litre? And Porsche themselves only managed about 70hp/litre from the Euro SC and 81hp/litre from the '72/'73 911S. Hell, I've got S cams and EMS and heapsa compression and only get 85hp/litre.

Mind you, if you assume a 15% transmission loss (rather than 9%), I have 290hp (free horsepower!!!!!!).

Actually I don't think Andial would BS it, they just might have gone a little further with the CIS?? I dunno...

[Bill Verburg]

I have been searching the forum for several days and have read a half dozen threads including one with a similar title for 2001.

I would like to get some input on rebuilding a streetable hot rod on 3.0L SC case with:

1st no worries about emissions/ no testing required
2nd max durability
3rd as a street/track car
4th the most amount of power you can obtain and still have the above (how about 275/300 hp as the goal)
5th costs must stay under 15K$ so no whiz bang engine management systems
6th no motor swaps to 3.2 or 3.6

I was with you up until item #6, as you were describing a 3.6 transplant perfectly.

I also do not understand the fixation on a heavily modified 3 liter. That will immediately negate item #2

People throw out hp #s as if they were real and comparable to each other, they are not, or at the very least are highly suspect unless all of the parameters which went into their development are known. The only consistant set of #s that I know to be reliable are factory published. So I will stick w/ factory specs

The factory got from 200hp@6000 in a 76 Carrea 3 to 315hp@8000 73 Carrera 3.0RSR from a 3 liter powerplant the former very streetable the later not. The 85 SC/RS was 250hp@7000 base and 270hp@7600 Rally, the former streetable that later somewhat less so.

To get the more elevated hp levels MFI was used w/ very aggressive cams high compression and lots of revs. The more powerfull engines are a ball on the track in a lightened car where revs are constantly kept up(very narrow power bands), good gas is available(for the high compression), and traffic is a non issue(part throttle and idle are rarely if ever a concern). On the street none of those things are true.

You need to honestly sit down and analyze what you want. Unless this is a dedicated track only car, what % of the time will it really see track use and what compromises are you willing to live w/ day in day out for the few track days a year that are actully used. On the street and track outside of a class(where displacement is limited by a rule) there is no substitute for displacement and its consequent torque.

You mention a 3.7 cis possibility, for comparable money you can get a 3.8RS with much better reliability, tractability and torque.

You mention carbs, which can be a nightmare to tune and will never run as seamlessly as Motronic or even CIS. The biggest advantage of carbs is that they do allow the use of wild cams, Again great for the track but not so for the street.

A very nice relatively inexpensive transplant package is a late 92 thru 94 964 or 95 993. rebuild w/ raceware rod bolts, 993ss cams, and a custom chip. All of this should easily be do able for under $14k(~$7000 for engine ~$1000 for cams ~$6000 for rebuild and install), you will have an honest ~300hp w/ gobs of torque and reliability. A stock 3.6 of any ilk is no slouch in a pre 88 car

If a 3.6 is not to your liking, the next best is a 3.2, again staying away from expensive p/c sets a 3.2 w/ 20/21 cams, ssi or better exhaust some head work, and a custom chip should easily be capable of a reliable tractable 240-250 hp.

The least desireable performance platform to my mind is the 3 liter. Here you have to replace the p/c for any realistic gains while you are at it 98mm p/c are the way to go but you just spent ~$3000 and still need to do the cams and rest of the rebuild for the same $4-6000 that the 3.6 rebuild would cost.

PS:I sat down and thought long and hard about all of the above, I put my $ where my mouth is, 3.8 liter 993RS vram IT lives!!

I know that I threw out some hp #s as well, I feel somewhat confidant as they were repeatable and produced at the same time and place as some known factory #s

Here is a nice link to some
3.6/3.8 data

[dd74]

Originally posted by rdane

Come on, a nice engine, better than a simple 3.2 conversion with a cam......for under 15K. Does everyone just give up and drop in a used 3.6?

You got me. If I had 15K I wanted to spend on my car, I can't see why I WOULDN'T look into a 3.6. It's reliability, at least as far as Jack Olsen says - and he races his - seems to match up to what I've heard from guys racing stock or near-stock SCs.

I won't knock modified 3.0s, but you still haven't outlined (or maybe you have, and I can't remember your earlier posts), what you plan to do with the engine.

Cam's engine has always sounded nice to me, but EMS and EFI, or whatever, is a slippery slope of cost.

3.5 to 3.7 sounds so outer-bounds of a 3.0, the 3.6 has got to be a viable solution. After all, anything larger than pistons that increase the displacement to 3.2, I believe, require work on the spigots and all sorts of other "other" stuff.

[mb911]

Rdane,

I have been trying to contact you about those rear seatbelts out of your 79. Please contact me at bimn@genevaonline.com and please include payment prefered and address etc. For some reason I can't email you directly it comes back undeliverable because of some spam software? Sorry everybody else for interupting your thread.

Ben

[rdane]

Ben, just answered you...if not call me at 425 391 3202 during the week.

OK back on subject. I doubt I am the only one who has ever ended up here. I have a decent 3.0L engine with the following up grades in the last year and 190K total miles.

Carrera hydraulic chain tensioners
Air pop off value
Turbo camshaft oil line restrictors
Webcam, performance grind, 20/21 camshaft
Heat sheets
Magnecor wire set
Turbo value covers
SSIs and a dual outlet Danke stainless
Close ratio on a 915 Factory ZF
Sachs Power Clutch
High Performance Aluminum Flywheel

Those were the easy and inexpensive upgrades as I pulled the engine to fix oil leaks from PO's poor maintance and over filling the oil tank by 4+ quarts and to put in the new tranny.

So now I have a "fun" car that I track a couple of times a month and use for DE....plus we use the car for recreational drives and the club tours. It is an occasional toy not a daily driver. My "hot rod", as I suspect many of the cars here are. I want more power and torque ......I have some financial interest in keeping this engine as it took a few bucks to get here.

I want more power. 3.2/3.4 CIS would seem to be an easy up grade. I have heard about the 3.6/3.7 upgrade keeping the CIS. Seems like a easy step up with more of everything and no more money really if you have to buy the P&Cs anyway. But it seems I must have missed something.....the 3.2 crank? How much are they and the machining to use them with a 3.0?

"Here you have to replace the p/c for any realistic gains while you are at it. 98mm p/c are the way to go but you just spent ~$3000 and still need to do the cams and rest of the rebuild for the same $4-6000 "

Thanks for the comments Bill, I know you have already struggled through this as far back as '01. Looks like 7/8K would do a rebuild from where I am at with a 3.4 at least. That sound about right?

"3.5 to 3.7 sounds so outer-bounds of a 3.0, the 3.6 has got to be a viable solution. After all, anything larger than pistons that increase the displacement to 3.2, I believe, require work on the spigots and all sorts of other "other" stuff."

What is the other "stuff" that I am missing that will push the envelope cash wise if I go from the 98x98 P&C 3.4 up to the 3.7?

Obviously I am missing something.

[Bill Verburg]

keep in mind that when purchasing upgrade parts separately the price goes up disproportionately.

98mm p/c ~$2500
cams ~$1000
valve train ~$500?
Headwork ~$500?
hardware ~$600
gaskets/bearing ~$500
L/s crankshaft ~$4000
enginemanagement ~$3000?
labor ~$3000?

Or you get most of the more expensive of the above w/ a 3.6 or 3.2

There are a ton of great threads and links in the archieves, heres a good place to
start

I think that Randys car(Iris) is very well done and would be a great model(except for the carbs part) but it wasn't cheap either.

I guess my main point is the given the street hot rod objective, you have 3 primary starting points

• 3L SC
• 3.2L Carrera
• 3.6L 964/993

Each will need similar work, w/ fewer additional parts necessary for the bigger blocks and better potential results