Surprise Xmas present from my 3.2 - broken head stud ... options for rebuild/upgrade?

[Maxhouse97]

Yep on my first valve adjust heard something heavy drop into the oil pan after removing the valve cover. Went through the several mental states (denial, shock, anger, determination and now upgrade potential). After reading engine rebuild threads for a while, I have some basic questions on the path to a rebuild. Am at early stages so please excuse ignorance. Trying to manage budget/personal time/upgrade.

Basics of the engine - 1987 US 3.2, 132k miles, full top end done at 88k with new valve guides and webcam 20/21. SW 93 chip. Motor runs amazingly and does not burn noticeable oil. Plugs were clean. Engine was out (shop) 3 years ago for trans work and external WYIT were fixed. OH 93 octane plentiful.

Current state - one broken Dilavar exhaust side head stud middle of the engine.

Current desires - keep spend under $8-10k if possible (this may eliminate all of the upgrade questions below). Don’t want to split the case (I’ve heard 3.2. bottom ends can go 200k, will take me 20 years to get there with the amount I drive). Want to do easy work myself, but with little kids have very little free time. Do have a four post lift.

Current plan (could be a pipe dream but that’s why I’m here) - remove the engine myself to save on labor, and send to a shop for a rebuild. Replace all exhaust head studs with steel. Fix anything else (seals, oil leaks, fuel lines, etc.). New oil lines for future SSIs (once the mythical Dansk larger ones come out).

Best upgrade path (as its hard for me to pay this much money and end up with the same engine I had) - Euro 3.2 pistons or 3.4. Heavily leaning towards Euro 3.2 for plug and play.

Questions:

- I’ve heard rod bearings can be replace without splitting the case, can they be inspected without disturbing? I’d like not to touch them. IMS bearing supposedly wears, can this be inspected as well? Again I’m hoping to avoid going in there, but want to eliminate a weak spot if possible.
- Euro pistons ... I’m fairly confident my P&Cs will be ok, what do you think about selling them as a set to defray the cost of buying a Euro set used? Or just selling the pistons and buying used Euro? Besides the cost of the pistons, how much added cost/work is this? I’ve read about rechecking clearances and C/R but not sure. SW said the only difference is 6 hp, but stock RoW had 231 hp and my car 217?
- I’ve read that JE 3.4 pistons are not much more than Euro, but I want to stick to stock Motronic and don’t need the extra headache (knock risk, extra head work for twin plug, etc.). Max Moritz JE 98mm pistons on single plug look enticing though.
- Or could I get the extra compression I’m looking for by using a thinner (head?) gasket or milling the bead itself? Read that as well.
- I do not know if I have KS or Mahle stock cylinders, does that change the above?
- In order to drop the engine myself on my four post I need to remove the exhaust (it won’t fit between the ramps). But I’m doing this I’m almost sure I’ll break a exhaust stud. If the cylinders are coming off anyways is this not a bid deal to fix?

Opinions welcome, thanks. Subject at hand...

[Nux]

Count the cooling fins on your cylinders: 10 = KS, 11 = Mahle. The latter is reusable.

The Euro 10.3:1 upgrade is very nice and will go nicely with your 20/21. Much cheaper than 3.4. The HP difference is noticeable but more so is the added torque. Do a valve job on your heads and off you go again.

If you do the rebuild your self - and nothing else need to be done - you should be well below 6k

[Maxhouse97]

Ok great just counted 11 fins 😊

Thanks, your description on the Euro 3.2 is exactly what I am looking for. I also like that it is a OEM configuration.

[tmaull]

Are you doing the rebuild yourself?

[Maxhouse97]

No I’m thinking of taking the engine out myself and then turning over to a shop as a long block.

[sugarwood]

At 88k, engine has been out for top end already
Engine out 3 years ago for WYIT stuff.
You yourself said bottom end can go 200k.
You don't drive the car much.
Seems like budget is a thing.

Why not go against the grain and just get the exhaust studs fixed ?
And avoid going down the rabbit hole entirely.
Especially if you're dropping the engine yourself.

[Maxhouse97]

Sorry it’s a head stud that’s broken, hence needing to at least take off that cyclinder to repair. And I would at a minimum want to replace all 12 lower Dilavar studs to prevent this happening again.

[Flat6pac]

You’ll want to check the guides with a valve job as there was some soft guides several years ago and you are removing the heads.
Bruce

[simmersonwheels]

Just in the same position with an 86 3.2, no broken studs but a pitted cam and oil consumption.
66 thousand miles, i did split the cases to check the bearings, and because I wanted new endless cam chains. The intermediate shaft brgs showed wear, I ended up replacing the mains, rod brgs, intermediate etc, carillos, supertec studs etc.
In retrospect I wish I had just done cams and heads, replaced the dilavar with steel, and buttoned it up.
"While you're in there" is a bottomless adventure sometimes.

[Maxhouse97]

Thanks guys, appreciate the feedback. The only thing in the bottom end that is really making think twice are the 9mm rod bolts.

[gtc]

Unpopular option: drive it for a while longer as-is.

[Trackrash]

Decisions, decisions. If you can drop the motor yourself, why not get Wayne's book and just fix the head studs. It gets done all the time. Pull the heads/ cam housings as a unit, pull the pistons and cylinders as a unit (don't remove the pistons from the cylinders), replace the bottom studs and put it back together.

I know it can be a slippery slope. Once off to a shop, it will be easy to be convinced to do an entire rebuild. From what I read probably not what you really need to do.

If you have good oil pressure and are not using oil, why not just fix it? Of course, once in there, if you find a problem, then it is a no brainer to do the repair. and BTW, yes, you can pull the rods without splitting the case.

Have you read this thread? The inside of an engine ....$20k top end valve job

[Maxhouse97]

Yep crazy thread, I saw the video.

I’d love to do it myself, just worried about my free time at this point in my life. But to your point, why couldn’t a shop do what you said for reasonable money? I understand they may try to upsell but I can make that decision, right? Guess that’s why picking the right shop will be important - someone that has a reputation for being competent and fair.

The only downside to that plan would not being able to install Euro pistons. I want to do rod bolts but folks say you can’t properly torque ARP bolts without splitting the case. Maybe I get the rods machines to accept 10mm 3.0 bolts?

Anyone recommend a shop within 2-300 miles of Cincinnati?

[Maxhouse97]

Just found this thread on rod bolts and replacing without splitting the case, mentions ARP but does not discuss the stretch gauge issue. I would not want to put 9mm stock bolts back in.

change rod bolts without splitting the case?

[Walt Fricke]

Max - I think you'll have problems trying to run 10.3:1 compression on 93 octane gasoline. Nux lives in Europe, and they have (or had in the 1980s when these engines were built) higher octane gasoline readily available. This engine doesn't have a knock sensor, and can't detune itself after sensing knock when you put the pedal to the metal.

If you aren't driving the car on the track, don't worry about the stock rod bolts. Yes, if you do replace the rod bearings it makes sense to use ARP or some other stronger bolts. But you don't hear of a rash of stock street motors having rod bolt failures. You don't need to run over 6,000 rpm, and typically in normal driving you don't get above 4,000.

If you change rod bearings without splitting the case you can't use the stretch method. But torqueing to ARP specifications works, as does using the factory torque and angle method. You just have to do it right.

I'd go with just stud replacement.

[Maxhouse97]

Thanks Walt. Good to hear on the ARP torquing method.

My apologies but I forgot to mention that it is a DE car, may be moving away from that direction now and looking to track something else but would still like the flexibility. I’d like to rev to redline consistently without worry (hence my thoughts on ARP bolts).

Also interesting on the Euro pistons, I have consistent access to 93 here in Ohio, did not think that would be an issue. I’ll do some research on that.

Maybe I’m odd here but I figure I’ll be spending at least a couple grand even if I just replace the head studs, really hard for me to swallow that and not get at least some performance improvement. Hence my thoughts on Euro pistons and ARP bolts - seems so easy with plug and play.

[cmcfaul]

10.3/1 compression is about the limit of pump gas. Your heads have been rebuilt and milled on the top which increases compression a tiny bit more (depending on how much they took off of the cylinders). Would be a nice performance improvement though. Maybe do something to keep temps down to lessen possible detonation (knock) as an offset. Colder plugs would be a recommendation as well.

Would not mess with the bottom end at all. Would do new chains if they were not replaced during valve job.

Just something to keep in mind.

Chris

89 G50 Carrera

[darrin]

why not get your cylinders bored to 98mm and build out a singleplug "max moritz" style engine with wedge pistons. Can run at a bit lower compression than the eurospec pistons and still get a nice performance boost for not much additional $$$

[Maxhouse97]

So I spoke with three separate engine builders yesterday, here's what they said (names withheld):

Builder #1 (<$80/hr labor rate) - need to split the case and essentially take everything apart (~$2k difference between splitting the case and not). Must use ARP head studs and rod bolts. Use JE pistons instead of used Mahles if Euro compression desired (also better ring package). Looking at $7.5-11k total depending upon condition.

Builder #2 (<$100/hr labor rate) - do nothing but replace lower head studs w/ OEM steel, not worth investing in new/different pistons (might as well do a full rebuild at that point), more fear disturbing rod bolts by trying to replace in situ than worth it. Engine seems to be running strong (I mentioned that it dyno'ed at 220 whp a couple thousand miles ago). Just fix what's broken ... basically what Trackrash suggested. $2k total depending on condition and assuming head studs main issue.

Builder #3 (<$90/hr labor rate) - full rebuild, $10k-15k depending on condition.

I was surprised by the variety, and how the builders basically driving the conversation by dictating what they were comfortable with vs what I wanted. I understand this because they have to back up the end result, was just different than what I am used to.

I am leaning towards #2, although I may try to convince him to at least replace the rob bolts. He mentioned that even though there is a lot of internet hype about the 9mm 3.2 rod bolts failing, you don't see them that much. That being said he also talked about only reving his 3.2 to 6k RPM, and I want to have piece of mind reving to the 6500 redline consistently. Both Steve W and John Walker say you can properly torque ARP rod bolts without splitting the case. But if he holds firm I will defer and take what seems like the practical approach of only addressing the problem and fixing the studs.

[smokintr6]

Did you by any chance happen to talk to the North End Wrench in Columbus, Ohio? That's definitely who I would be looking to in this part of the US. I would definitely be leaning towards #2 also. Is he pulling the engine out as part of the $2k? I would also not be a fan of doing the rods in situ. I would want to pull all the rods out, resize them for the ARP hardware and reinstall. I can't imagine getting the stretch gauge in there while the case halves are in place, but you never know. It might only add $1500 to your bill to have #2 split the case and recondition the rods. That would give you peace of mind, and at least have eyes on all the bearings and assess the general condition. Sometimes thrust washers and intermediate shaft bearings look surprisingly used up on these things.