SWB Head Stud upgrade- worth it??

[Mighty2.0]

I've finally accepted that I must overhaul the engine in my '66.
I've done many searches on head studs. After comparing the notes and prices, I still can't decide which to use.

Here are the (tentative) parameters:

1. Basically stock, w/ mild upgrades, e.g. possibly bore to 81mm, 9.5CR, leaning toward JE custom pistons.

2. Massaged or reworked camshafts to match piston configuration.

3. Stock heads, but ported. I am considering installing larger valves.

Stock Weber carbs (will have redone).

Question 1 (of many): Are Raceware, ARP, or Supertec head studs really worth the extra cost & expense? I'm not doing anything insane here, so up to $800+ seems like overkill to me.

Question 2: The steel studs seem fine. Am I OK using just these, given that I will still have so many other expenses, and I still have to send the carbs out, etc. etc.

On it goes!

[Steve@Rennsport]

I use and recommend the stock steel head studs for these engines. I see no need to spend money on something that isn't better than what you have.

[Will 1967]

Originally Posted by Steve@Rennsport

I use and recommend the stock steel head studs for these engines. I see no need to spend money on something that isn't better than what you have.

Are they OK on early aluminium case even if you use larger Nikasil cylinders (and also pump up compression etc)?

[Fritter]

Subscribed

[304065]

Welcome back to the Forum, it's been a while. I hope your beautiful Polo Red '66 is otherwise well. The good news is, there's a nice trail of bread crumbs here- search for 901/05 for everything I know about rebuilding 2,0 liter engines.

Upon the advice of many, I went with stock steel studs. The old ones were probably fine, but I did it as precautionary measure.

[Steve@Rennsport]

Originally Posted by Will 1967

Are they OK on early aluminium case even if you use larger Nikasil cylinders (and also pump up compression etc)?

No worries, mate,.....

[Walt Fricke]

Studs seem to have two issues: pulling out of the case, or breaking. The pulling seems to be an issue with the magnesium cases, exacerbated when the spigot is bored for larger cylinders so the wall to stud threaded hole metal gets thinner. Not your issue.

The breaking seems to happen with at least some of the dilivar studs Porsche used when playing catch-up with the pulling issue, which only happened after the motor (2.7 especially, aggravated by thermal destructor exhaust smog systems in the US, etc) had a fair number of miles on it. Porsche's 2.0 race motors used stock steel studs, I think, to crank out 210 HP.

Your sand cast case is the case of choice for most hot rod motors under 3.0 liters. I have a 2.7 race motor with this case, and head studs have never been a problem.

What you might want to spend your spare $ on is piston oil squirters. All the mag cases came with them, as did the later die cast aluminum cases. Your case does not have them, but a machine shop can do the drilling and install them.

Another thing I'd consider is a larger oil pump. Maybe one from an SC or 3.2. Late 2.7? A bolt-in, no downside I can see (other than a few more $). Doubtless you are doing the case oiling mod?

When I hot rodded a 66mm crank race motor all I could purchase were stock rod bolts, which weren't up to 8,000 rpm (Steve would have told me that had I known him back then). You might consider aftermarket higher strength bolts, which I think now can be had for the stock 66mm crank rods. Maybe overkill for a street motor, but you will be replacing those bolts anyway.

You have the specs for the '69S motor to guide you, right? Those heads (or their dimensions), S cams. The '66 didn't have the Birals, did it? Relatively easy to have those bored to 81. In the olden days that was popular as a way of reusing worn barrels, and SCCA OK'd it for their purposes. I wonder if that is worth it outside of class racing (unless you are having yours rebored due to wear).

Like you, I am wondering if I can use the pick of my many steel studs on the short stroke 2.8 I am slowly building using an early turbo/carrera 3.0 die cast case. I have a large supply of old studs which buffed out without rust pits or stud puller gouges (plus a bunch in the "maybe I'll find some other use for these" bin). On the other hand, this is to be an 8,000 rpm race motor. So for me the answer may not be quite as clear, and the fine threads on the head end are a nice to have upgrade.

Walt

[Henry Schmidt]

Why not use the best studs available?
Supertec Head Studs. They produce a far more stable platform which means a longer life expectancy.
They are available from our host.

[Walt Fricke]

Cost, of course. A guy could replace the case through bolts from an early engine with the ones from the 3.2s or somewhere, where Porsche went to a finer thread. That's an improvement. But is the cost worth it if you already have the older stock ones in hand?

[Henry Schmidt]

Originally Posted by Walt Fricke

Cost, of course. A guy could replace the case through bolts from an early engine with the ones from the 3.2s or somewhere, where Porsche went to a finer thread. That's an improvement. But is the cost worth it if you already have the older stock ones in hand?

Yes, if your goal is to build a top quality engine.
The head stud that Porsche makes is a compromise that I'm not willing to make.
Choose your compromise as you see fit.
Penny wise and pound foolish comes to mind.

[Mighty2.0]

Hi Everybody, and thanks for your input.

Here is what I'm looking at so far:
Case:
Oil bypass mod.
Case squirters
New through bolts, nuts, washers
I think I'm going to use new original steel head studs and hardware.
New Carrera oil pump, with modified plate.
I wanted to keep the flat plate look, but it looks like the later pump is the way to go.

Heads:
Can I have larger valves installed in my stock heads?
What is downside, other than having to match to pistons and cams?

Pistons:
Leaning toward custom JEs in my reconditioned barrels, similar to yours, John. Those are beautiful!


Cams:
Will use original cams, reworked to match heads
Already installed 930 type non-pressure fed tensioners and spacers in 2007 (will post separate thread & pics of failure, if interested- phew- no damage!)

Carbs:
Will have original Weber carbs reconditioned / overhauled


Exhaust:
Will have the stock, original heat exchangers blasted, and coated with “something”, I haven’t researched this yet.
The “cover” piece on one is a little loose, can this be welded to “good as new” condition?
Surprisingly, it doesn’t rattle (or you can’t hear it anyway), but it is loose to the touch.

Issues:
1. I really don't know what I'm dealing with on this motor, and won't know until I have it apart. I do know the case was split and a cylinder replaced in the early 90s, but this was more of a "get it back on the road" type of repair. Big shout out to the dope who put a humongous strip of JB Weld along my case seam! BLARG!

2. I would like to send my case out to Ollies or Competition Engineering. How do you coordinate different people performing different work on the various parts, without things getting confused or not done to match? Guy who does the heads says, "well, I wouldn't have done X to your cams", etc. Guy who does the case says, "well Bruce messed up your heads!", etc. Should I just send everything to one place?

3. The guy here is in the business over 40 years, but his shop is a mess. It's hard for me to see how he assembles spotlessly clean engines there (as stipulated in Wayne's book). I haven't asked him, because I don't want to insult him or his place. He has helped me a lot and is a good guy, but I have my doubts as to the cleanliness and attention to detail. It's just what I see. I'm worried about folks cutting corners, thinking "this guy won't notice".

At this point, I'm leaning toward sending everything out and assembling it myself -that way I only have myself to blame is something goes wrong, and I've got a brand new garage floor, workbench and remodelled work space to boot.

[Mark Henry]

Originally Posted by Mighty2.0

Heads:
Can I have larger valves installed in my stock heads?
What is downside, other than having to match to pistons and cams?

Pistons:
Leaning toward custom JEs in my reconditioned barrels, similar to yours, John. Those are beautiful!

Shameless plug, but I have a set of "copy" 69S ported and polished heads and 80 birals in the classifieds. It would get you a long way there.

[Flieger]

Assembling an engine yourself is an interesting process, something I have a goal to do someday. If you do not mind being out of use of that engine for a while, it is a great way to go. Give yourself all the time you need- pressure makes sloppy work.

I have seen some great mechanics with many years of experience who have "messy" shops. The mechanics I am thinking of just have a different way of organizing. Their work is top-notch. YMMV

[304065]

I don't see any reason NOT to do it yourself-- and with the forum as a guide, you should be able to avoid a lot of the pitfalls that I had to figure out from experience.

In terms of where to send things, I think you can divide the work up among various contractors with no problems. Some guys do heads REALLY well and can also do the case. For example, I wouldn't hesitate to send the whole package to Steve Weiner. In my own case I sent my case to Ollies for squirters, oil bypass mod, clearance for bigger oil pump, ceramic tumble and then a thorough cleaning including R&R of the oil gallery plugs. Ollies also cleaned and surfaced my cam towers and valve covers-- I sent those later but should have sent it all at once.

For heads I used Bob at Anchor Atlantic, not too expensive. I bought NOS intake valves and used SI valves (thanks Henry Schmidt for the tip about SI) for the exhaust.

You could be looking at BIG dollars to change the valves in your heads, and you would presumably want additional port work as well. If you are doing a 2,0 (80 or 81 x66) or a 2,1 (80 or 81 x 70.4) I don't think I would bother. Sure, you could put bigger seats and valves in and port the heads to 69S specs, and it would all look original from the outside, but then you've got perfect ports with the lousy single-plug 72cc combustion chamber which is prone to detonation. You would be better off to score a cheap set of 70-77 heads which already have bigger (and cheaper) valves and have those ported-- only a purist like me would take points off because you don't have the original casting number on the fins (which is DAMN hard to see around the heat exchangers from under the car!) Anyway if you were to modify the original heads you should probably twin plug while you are there. You don't have to use the second set of holes right away, they can be plugged until you are ready!

On the cams, there are "modern" grinds that are better than the original Solex. Talk to John Dougherty (camgrinder here) about what you want to do with the engine, he'll set you straight. At a minimum I would consider the "mod-solex" grind-- this will get you an improvement over the original and yet isn't so radical.

I assume you are not going to use external oil cooling, that's a dead giveaway that the car is no longer stock. Be sure to have the engine oil cooler ultrasonically cleaned and pressure tested.

Good luck! We're here to help and I have personally been down this EXACT road yourself. It's fun to do it yourself, not that hard, time consuming, but if you don't have confidence that your local wrench can do a clean, perfect job, I wouldn't hesitate to go elsewhere. It's a $10,000 proposition, you want it done RIGHT.

[304065]

ps you don't need to use the Carrera pump with the bowl sump plate-- you can use an SC pump which is the same except for the venturi on the suction end-- and you can use the flat plate. The bowl plate is a dead non-stock giveaway.

[Mighty2.0]

Hi John,
Is the SC pump still available? It isn't listed on this site.

I kinda liked the look of the "vintage" aftermarket pump plate for the Carrera pump that Wayne has listed here.

Here's a quick pic of the car.

[Walt Fricke]

Come on - you tease us with just a picture of part of the back end?

Does the car look as nice in person? Is that original paint?

On oil pumps, just get a used one in decent condition.

The pump size increased around 1976, when the oiling mod came in - the two went together. Those pumps had a pickup that worked well with the flat plate. At some point in the SC range the pickup was changed some (pump stayed same), and there were pickup problems. Then there was a fix for this, which could I think be retrofitted at oil change time, so not a big deal - a better way of sucking the oil out of the sump. Point is, you can get a used pump with the capacity you want and in good, functional condition for rather a lot less than a new pump (assuming there is still some NOS out there for these pumps). Many of those 2.7s which got replaced by 3.0 and later motors ended up as parts. Pump failures were not one of their problems. Short of disasters like running out of oil or engines blowing up, they seem to hold up pretty well - they are, after all, well oiled all the time.

Walt

[304065]

Walt,

You can now buy a repro venturi that goes with the flat plate sump cover-- allowing you to use an SC pump with the updated venturi. While this probably isn't as good as the deep SC venturi with the bowl plate, my guess is it's better than just the pipe sticking through the sump screen?

[Mighty2.0]

Hi Walt,
Sorry, I haven't gotten around to taking many pics of the car. I do have some pics of some of the work I've done. I can post these on the tech forum.

Yes, the car looks good in person, about as nice as you would want on the street IMHO.
No, unfortunately the paint is not original. The car was painted sometime in the early 90s.

Thanks for the info, still more questions:

1. Is the SC pump available new?

2. How can you tell if a used pump is still "good"?

I'm reluctant to spend all this money on a rebuild, only to install a used pump. I've been burned on used parts before- too many times, the parts I received weren't any better than what I had.

3. Is the installation of a new Carrera pump w/ the modified plate an unpardonable sin?

4. Wouldn't twin plugging the engine be a "dead giveaway" the car is non-stock also?

I couldn't post a pic, but it's called the "Vintage sump plate", sold by our host.

[Walt Fricke]

Well, you are as well (or poorly) placed to look for new pumps, SC, 3.2, or late 2.7. Since both PP and a source I sometimes use only show the 3.2 pump available, that's probably the case. No reason for Porsche to keep making old parts when it has a better one which will fit. As of at least 1995, Porsche said the earlier pumps were no longer available.

Because of my belief that most pumps last a long time, the only new pumps I have purchased have been a 930 and a GT3, both for race motors. You don't need that much pumping power, they are pretty expensive (though the cost of a new 3.2 pump is not insignificant), and you have to modify some of the case internals (not a big deal, but has to be done).

Wayne's engine rebuilding book, and Bruce Anderson's 911 book, both have nice pictures of the various pumps. Anderson shows the one John Cramer just posted here, which is the factory design to solve the issue early 3.0s had. The dimple is for the drain plug, so you can use the flat plate with plug, and no one will be the wiser if you get a used '76-82 pump and that sump screen/venturi piece. (I bet late '83 3.0s got the 3.2 pump/screen, because they also got the new case without a separate sump plate when Porsche ran out of the earlier cases and the dies for them wore out).

You'd think that there would be some sort of oil pump testing rig, where an electric motor would spin the pump, and it would put out X gallons per minute or Y PSI through controlled orfice Z. But there isn't. I've poured oil in one side and spun it by hand, but that's pretty crude and was more for cleaning after some engine disaster, and I should have just disassembled it for that purpose.

Instead, one inspects the pump. You can see through the openings if the pump gear teeth are badly worn on their faces, and if the edges of the gears, which need a close clearance from the case, are all beat up or still have nice machining marks on them. If more concerned, you can disassemble the pump, which is not hard, and do a closer inspection for the same visual stuff, and look for scoring on the pump body ID. There is the end clearance someone came up with, which can be checked and even adjusted if it has gotten too large.

I am fortunate, in that there are at least two Porsche dismantlers within easy driving reach. I could dismantle/inspect a used pump there, or bring it back if further inspection shows it is bad. You may not be so lucky, though. I've had good luck with pig in a poke parts purchases, but haven't made many. Easy to see how a seller (who might simply not know what is good and what isn't) can deliver worn out stuff.

I'm the wrong guy to ask about the value of originality. My '77S has 3.0 flares and motor and transmission, and an '85 front clip through and including the dash board due to a racing incident. Hood pins, front center oil cooler and valance with brake ducting, IROC tail. Race seats, Wink mirror, full roll cage.

No way you can hide twin plugging if you are using it. If you aren't, but want it available in the future without tearing the top end off, you just put spark plugs in the 6 lower holes, and put the stock exhaust valve cover over them and leave things alone. Just don't claim a stock engine for the SCCA national autocross championship event. I favor 12mm plugs for the lowers if you do this - fewer clearance issues with the head stud fasteners, and no downside I can think of - having two types of plugs in your personal inventory is hardly an issue. With your high domed pistons, twin plugging (and using it) is the way to boost the squeeze some and still run pump gas through carburetors. You can, of course, always cut costs by cutting performance expectations - just how much power will you really use on the street?

Walt Fricke
who marvels that he can install in a '66 case the pump used in current GT3 racing motors, with only some modifications you can make with hand tools for clearance - the bolt spacing and port spacing is the same.