81 RoW SC rebuild questions

[SpeedracerIndy]

I have an 81 RoW SC with around 100k miles and one broken head stud, and I want to rebuild it myself. Aside from some oil seeping where the broken stud is, it doesn't leak a drop of oil. I just try not to drive it because I don't want to risk damage from the broken stud. I rebuilt the transmission myself and have pulled the engine a few times so I have most of the tools I need already. I'm just wrestling with what to do with the engine and what i can afford as it's been many many years since I looked into this. I have a budget of $10k, but I'd like to keep it around $7.5k if possible.

It's a 9.8:1 euro motor with SSIs so it is already a pretty good runner, but I'd love to throw a few upgrades at it while I'm in there if I can afford it. I had it on a dyno after installing the SSIs and it put down 190hp at the wheels. When I was looking at rebuilding several years ago, a 3.2SS was the way to go and would get me around 230-240 (at the crank?). So that's only 15-20hp for quite a bit of money, or am I analyzing that wrong? Is a 3.2SS still the way to go or are there other options available now?

Any advice from the experts? Thanks!

[SpeedracerIndy]

No feedback? Did I say something wrong, LOL?

It looks like there are places that will over bore the cylinders to 98mm and re-plate them with Nikasil (EBS???). Then I would just need the pistons to match. Should be cheaper than buying all new cylinders. Can the stock CIS handle the change in displacement?

[Flat6pac]

You need to find Carrera cylinders because they don't like opening to the SC head gasket for 98 mm
I didn't comment on the first post because to me it doesn't make sense to throw out 9.8 Mahle for the cost of what you want to do.
You want to do a 3.2, do it with a crank and rods, it will tend to be less costly.
Bruce

[SpeedracerIndy]

Originally Posted by Flat6pac

You need to find Carrera cylinders because they don't like opening to the SC head gasket for 98 mm
I didn't comment on the first post because to me it doesn't make sense to throw out 9.8 Mahle for the cost of what you want to do.
You want to do a 3.2, do it with a crank and rods, it will tend to be less costly.
Bruce

Bummer, didn't know you couldn't bore SC cylinders. That ups the cost considerably.

So a crank and set of rods will be cheaper than a set of P&Cs?

How does a 3.2SS drive compared to a 3.2 regular stroke?

What I want to do is rebuild the motor, and get a modest performance increase out of it without breaking my budget. I'm looking for a very streetable (good torque) engine and will likely not track it. I have always heard that the 3.2SS was a good setup for a street motor. I'd welcome your advice if you think I'm not going down the right path.

Thanks.

[wreckah]

if you open up the engine, you're already going to have quite a few spendings:
- full revision of the heads
- new studs
- new seals/gaskets all around
- maybe clutch maintenance/replacement
- new cam chains/sliders
- pistons rings
- tools (to remove the cams, set cam timing)
and a bunch of other small things which you will find when you are 'in there' (exhaust studs, refurbing the engine tin, etc...)
- maybe it's worthwhile to open up the case to check bearings/crank/rods and replace everything and have the crank polished

if you do everything yourself (apart from the heads which is not really DIY), you'll have some change from your 10K for sure, but not enough for P/C i don't think...

maybe consider EFI conversion? I cannot really see how stock CIS can cope with a properly more powerful engine, or at least one that has more potential than the stock 3.0L.

I think EFI on stock 3.0L will gain you more than say a 3.2 on stock CIS...the throttle response alone is already worth it IMO

good luck,
Jan

[Flat6pac]

Well, the cases are the same 3.0/3.2 internals as are the oil pumps. Get the pump flowed at Henry's supertec.
I have a nice set of 3.2 Mahle s 9.5 cr
Standard 3.0 crank and rods have a nice value. Throw in a few hundred extra for the 3.2 crank and rods. Buy the 3.2 before selling your 3.0 crank. The SC 9.8 have a real nice value so that can be a wash
So, at this point, you have less than $ 1k out and you're at 3.2
Money to spend, buy a set of 3.2 euro at 10.3/1
CIS will do good
Bruce

[SpeedracerIndy]

For some reason a 3.2SS still calls to me. With the option to add EFI at a later date. Talked to EBS and they have 98mm MAHLE cylinders with MAHLE pistons @ 10.0:1 made for CIS single plug for around $3400. Less if I can find a set of used Carrera cylinders to bore and plate.

One reason I'm shying away from a Carrera crank is that I don't think I want to split the case. Plus, aren't Carrera rods (or rod bolts) weaker than the 3.0 setup?

[Flat6pac]

But, you shouldn't put all that new head work, P/Cs, new rings on top of an old bottom end
Bruce

[Catorce]

Just doing a 3.2 SS right now. I used 3.2 carrera cylinders bought used (450), sent the cylinders off to US chrome to bore and plate (1.1K), then used JE 9.5:1 pistons made for this purpose on their site (1K).

That part is easy. I am doing a full bottom end rebuild on the cheap, but you have to keep in mind I get wholesale pricing and I have done this a hundred times (it feels like).

I am into my quick and dirty build about 6-7K, including headwork (new valves, springs, guides) and a 964 cam regrind. Everything else was cleaned up, repaired, and resealed.

It can be done.

[30westrob]

If you are not going to split the case then fix the head stud problem and concentrate on lmproveing top end flow. 964 cams with mild porting of the heads would yield a good performance improvement for reasonable $. You already have one of the best 3.0 L production engines built. Rob

[SpeedracerIndy]

Thank you all for the advice. The more I hear the more a 3.2ss doesn't sound like a wise way to spend my money.

Any advice on who can port the heads while they're being rebuilt? I am planning on sending them somewhere to have them refreshed since I don't have the tools to do it myself.

Hmm, maybe I'll have to look at EFI now. I have a turbocharged Miata that I put a megasquirt 3 on so I have some experience with it.

[30westrob]

I have had very good experience with, Ollies Machine, but there several Porsche machine specialists that frequent this site with outstanding reputations. Rob

[ninesixfour]

Stock class 9.8:1 Euro SC engines built by the top shops in the PCA club racing world make 215 at the wheels. Big port USA engines make about 195. I think their tricks are in the compression, advanced timing, and possibly higher octane fuel.