Budget 3.2 head stud replacement project

[fred cook]

Cleanliness IS next to godliness! I am in the process of building an engine right now and so far, about 1/2 of the time spent (5 weeks since engine drop) has been used cleaning parts. On the engine block halves, I would clean on them until I thought they were done, go back the next day and see places that needed more work. This went on until I could not find any more spots of grunge that would come off with any of the several brushes that I used nor would be affected by any of the cleaners. I don't have access to a soda or dry ice blaster which would have done a more perfect job, but with enough effort and attention to detail a good job can still be done without them.






[QUOTE=Henry Schmidt;7483152]Cleanliness is next to godliness. I like everything as clean as possible. And demand it of my product.}

[Henry Schmidt]

Originally Posted by Mr Project

Thanks for the tips on how to keep the gunk from the inside of the case. Of course I have my own sandblaster as well, so that work still on my list.



Fair enough. I'm a pretty astonishing guy, really, when I think about it.

I thought the same thing when I got down to the block. I actually know better than this, I essentially followed the steps you mention on the last couple of Subaru head gasket jobs I did. I just got excited about teardown in this case and was more nervous, not knowing the motor intimately, about where I'd get pressurized water and not know it when I wasn't planning to split the case.



Henry, I have great respect for your experience and expertise. I'm trying to balance the realities of likely failures on this future 99.98% street car vs. the likelihood that I will be in for another $5-8k because when I split the case, recon the rods, do bearings, etc., how could I justify not doing rings, P&C, rebuilt heads, etc? Right now the scales are tipping in the 'leave it alone' direction for me.

These price are just estimates, not an offer to perform the work

Rebuild rods $200
Rod bearings $180
ARP rod bolts $280
Case gasket set $80
Reuse mains $0
Reuse chains $0
Reuse oil pump $0
Intermediate bearings $80
Check crank $ 60 If crank has issue you dodged a bullet by finding it now.
case labor ? I don't know what your time is worth
Dry film lubricant on new and used bearings $90

There's nothing else in there, where is the the $5000?
Oil consumption from worn rings or valve guides you can live with, a magic window from a thrown rod, not so much.

Originally Posted by Mr Project

If I throw a rod in a couple years I'll eat my crow and take my lumps for it.

I've seen three of these types of projects lose a connecting rod within 250 miles.

I bought an engine with a good history (known) from a totaled car, did a valve job and rings, drove it a while only to find a rod knock.
My assumption was that no one drives a car with a rod knocking. Later we found out the throttle stuck on impact.
The gamble is really in the history....How well do you know the history?

Good luck

[keynsham1]

It is interesting having read this and other threads that the opinion of specialists particularly is that you should pull everything apart and fully rebuild the engine if it is out. I have my engine out to replace head studs and that is all I am doing. If the bottom end fails afterwards, then I was going to anyway even if I hadn't taken the engine out! I have a little more faith than a lot of people on these threads that these engines are not actually complete rubbish, and have some chance of staying together. I keep being told what great engineering goes into them after all. I have partially rebuilt many different engines n the past without problems. I don't expect, provided correct procedures are adhered to, that this one will be any different! Maybe I am wrong and Porsche engine engineering is actually rubbish after all??

[Henry Schmidt]

Fred, your project is looking great. Keep it up.

[Lapkritis]

Originally Posted by Henry Schmidt

Oil consumption from worn rings or valve guides you can live with, a magic window from a thrown rod, not so much.

To be fair, nothing to say you won't miss a shift with your new full engine rebuild and over rev on the test drive either. There is a time and place for a full rebuild and case split. That time may be always if advising other people how to spend their money for the maximum assurance. Reasonable assurance is another thing entirely. We all pack our own chutes but we trust the seamstress.

[Henry Schmidt]

Originally Posted by keynsham1

It is interesting having read this and other threads that the opinion of specialists particularly is that you should pull everything apart and fully rebuild the engine if it is out. I have my engine out to replace head studs and that is all I am doing. If the bottom end fails afterwards, then I was going to anyway even if I hadn't taken the engine out! I have a little more faith than a lot of people on these threads that these engines are not actually complete rubbish, and have some chance of staying together. I keep being told what great engineering goes into them after all. I have partially rebuilt many different engines n the past without problems. I don't expect, provided correct procedures are adhered to, that this one will be any different! Maybe I am wrong and Porsche engine engineering is actually rubbish after all??

In fact, when it came to the engineering involved in the 3.2-3.6 connecting rod, it was complete rubbish. The weight of the piston vs the 9mm rod bolt cross section is indeed a bad design. That combined with bad rod angularity (worse as the engine got larger) and an incredibly arcane oil delivery schematic, makes the rods susceptible to failure. I've seen rod nuts finger tight upon disassembly of good running engines.
If you don't believe me, try to buy a good used crank for a 3.2 or 3.3.

On a side note: Porsche never used the 9mm rod bolt on any 911 based race engine.
Why is that?

[Henry Schmidt]

Originally Posted by Lapkritis

To be fair, nothing to say you won't miss a shift with your new full engine rebuild and over rev on the test drive either. There is a time and place for a full rebuild and case split. That time may be always if advising other people how to spend their money for the maximum assurance. Reasonable assurance is another thing entirely. We all pack our own chutes but we trust the seamstress.

The truth is, with a properly assembled engine, you can survive a miss shift or 10 because you would have replaced the suspect rod bolts with a stronger (ARP or Raceware) bolt.
But that's not the point.
If you are that far into a 3.2-3.6 engine it really doesn't cost that much as I illustrated earlier so that is the "time and place". If your rod does fail, you could/will be looking at a huge bill.
Of course as a professional I do it right as often as budgets permit but some "while you're in there'" things are warranted not just a luxury.
As a poker player I understand risk vs reward and I would rarely risk thousands on unknown rods/ bolts in a 3.2.

[Lapkritis]

Henry, you're pretty focused this early in the morning so you must be enjoying your second cup o'joe. Rod bolts won't save you from valve float. You can very well reason your way into anything with these engines. This guy titled this thread as budget so let's help him with that in mind. Your experience is finger tight rod bolts? I'd recommend an LS1 swap to escape the nightmare of inferior design. Otherwise, maybe he should just confirm torque on those instead of spending a grand minimum on a case split? Food for thought and fuel for the fires this morning.

[Henry Schmidt]

I live on a farm, so I've been up since 4:00. It's never too early to offer accurate, well established information (facts) to assist people in determining their best course of action.
Accurate information is never a bad thing when you're in the process of navigating a project, budget or not.

[Lapkritis]

Originally Posted by Henry Schmidt

I live on a farm, so I've been up since 4:00.

Me too. Cows, chickens (meat and laying), pigs, and turkeys year round. 3 dogs keep watch. Sometimes foxes and coyotes but they're "dispatched with prejudice".

Truth is sometimes the very best doesn't fit. Might be why giving advice to DIY folks when you're a professional where things must be perfect is such a task. Some of these are $10k toy cars so an additional $1k engine work on something that's working perfectly fine on a street car is hard to justify. It's a different measure than someone like you building vintage race engines that are punished and warrantied. Different methods will certainly apply.

[Henry Schmidt]

This whole thing is getting crazy again.
We're not talking about vintage race engines and what ifs. This is a specific engine.
A 3.2 with unknown history "newly acquired" that is disassembled to the case.
The weak link in this engine and all 911 engines that use 3.2 rod with 9mm bolts (not all Porsche 911 engines) is the rod design and oiling to #2 and # 5 rods.
History shows unexpected catastrophic rod failures in these engines with severe financial consequences are common.
As long as you [editorial you] have all the information before making your decision, you can take the risk intelligently. I'm not telling anyone to do anything because I don't have their personal information (budget, skill set, time frame, etc). What I do have are the real facts [about how these engine work, how & why they fail] and that is what I share.

[Lapkritis]

Do you case split each one of these that doesn't have ARP rod hardware? If rod failures were that bad then there should be a class action suit to get in on.

[Henry Schmidt]

Originally Posted by Lapkritis

Do you case split each one of these that doesn't have ARP rod hardware? If rod failures were that bad then there should be a class action suit to get in on.

All 3.2-3.6 Porsche engines with unknown history need to have the rod bolts replaced. IMPO
If this was a 78-83 911SC engine, I would most likely say "run it".
Asking me (Supertec) what we do is irrelevant because we have a specific service. We only do complete overhauls, product development and machine work on 911 based engines.
We don't do R&R, we don't tune or repair engines and we don't service cars unless they belong to me.

[safe]

I agree with Henry, its so little extra to split the case if everything is alright and if it's not you are lucky to have caught it! Its mostly time and that is "free".
I recently split my 3.6 (valve guides) and everything except the ims bearings checked out, but I didn't know that before hand. I chose to put in ARP rod bolts as well, $250 on ebay I think.

[dtw]

This wouldn't hit Henry's radar as he is in the business of going down to the crank - but some DIYers also get good results with pulling the rods without splitting the case. This DIYer probably wouldn't ever do it - but it is a perfectly valid approach. Me, if I'm going to that much effort, I'm just going to split the case and, at a minimum, renew the intermediate shaft sprockets, timing chains, intermediate shaft bearings, snout bearing o-ring, etc. Measure the crank and mains, probably re-use the mains (especially considering the cost and crap quality of current bearing sets), inspect oil pump gears, DFL all bearings. Splitting the case doesn't have to be a super-costly exercise and peace of mind is priceless. On the engines I've built, they get taken to redline every time they're driven without a second thought.

Henry's point remains valid, whichever technique you use to renew the rods - specifically on a 3.2, they are a strongly recommended 'while you are in there' for an otherwise unknown engine. I have absolutely no idea why some are trying to bring valve float into the discussion when we're just trying to address a specific, known weakness in the 3.2 engine that can be mitigated while the engine is down this far. Not every thread has to be a dick measuring contest.

[Henry Schmidt]

I addressed the issue of replacing rods bolts and bearings without splitting the case in post # 18 but suggested that was rarely a good idea.
Rod bearing fit with respect to engine life is critical. When you measure the rod journals it is not uncommon for the journal to be egg shaped. If so, installing a new bearing on that journal is questionable. Measuring each journal through the whole and getting accurate numbers is difficult if not impossible.

[dtw]

Originally Posted by Henry Schmidt

I addressed the issue of replacing rods bolts and bearings without splitting the case in post # 18 but suggested that was rarely a good idea.
Rod bearing fit with respect to engine life is critical. When you measure the rod journals it is not uncommon for the journal to be egg shaped. If so, installing a new bearing on that journal is questionable. Measuring each journal through the whole and getting accurate numbers is difficult if not impossible.

Missed that - thanks for the heads-up. Great info.

The OP has been armed with options and info at this point - may he use his budget and best judgment to arrive at a plan he (and his 3.2) can live with.

[Lapkritis]

Originally Posted by dtw

... I have absolutely no idea why some are trying to bring valve float into the discussion when we're just trying to address a specific, known weakness in the 3.2 engine that can be mitigated while the engine is down this far. Not every thread has to be a dick measuring contest.

Dick measuring.... then why bring the Big Johnson and demand a full smorgasbord case split and dollar burning party on a guy that wanted to only replace head studs? He's been advised of the notoriety of the hardware within his physical reach. Another $1000 and a couple weeks worth of evenings may or may not be in his plans.

[dtw]

Nobody's demanding anything. Back off.

Quote de dtw

... I have absolutely no idea why some are trying to bring valve float into the discussion when we're just trying to address a specific, known weakness in the 3.2 engine that can be mitigated while the engine is down this far. Not every thread has to be a dick measuring contest.

Dick measuring.... then why bring the Big Johnson and demand a full smorgasbord case split and dollar burning party on a guy that wanted to only replace head studs? He's been advised of the notoriety of the hardware within his physical reach. Another $1000 and a couple weeks worth of evenings may or may not be in his plans.

[whiz05403]

Where can I find these fuel replacement lines from Len?