The tensioner upgrade has become rather expensive in the last years. Black, you are literally the first person (other than a local air cooled VW/912 shop) who has not insisted shuffle pinning.

CIS cams were the at the top of this list until I pulled off the CIS and realized how clean the motor would be with carburetors. To be honest, I'd be very surprised if the CIS doesn't need a complete rebuild ~ it was hit hardest during the PO's storage over the last few decades.

We'll see more about the case when I get a better look at it. It's fairly covered in road grease and grime.

The 3.0 I suspect is in need of an overhaul too. It'll be replace with this motor and rebuilt at that time for the next project it goes into.

If I remember correct, Bruce Anderson said shuffle pin it and I did.
People in high places have advocated doing this to Mag cases..Not AL cases.
I have no regrets doing mine, or the tensioners.
Peace of mind in the end.
Do it the way you want .
With the cam oil restrictors and oil mod this will be the 1st time in your life the oil tank level reading will be correct.
A nice benefit.

As I understand it, shuffle-pinning a 2.7 isn't necessary unless you are planning on trying for 250+ horsepower. Most of the performance books rate all their top 2.7s for the street at under that, I think.

I have the bad habit "whilst there" ..might as well.

I may go shuffling away just for the peace of mind.

Accurate reading of oil gauge is a convenience I am looking forward to.

IF anyone poos poos the oil restrictors go back in time here.
They have been discussed at leanth.
Its is all good, not just my opinion but the top dawgs too.

3.17.16 Updates and ?'s
 

Yesterday I had received my P202 & P203 ahead of schedule and so therefor rushed to the shop to get the cam nuts off. After 45 minutes of putting what was way too much torque through the motor using a 3' extension added to my breaker bar the left side was not going to budge and I was at risk of snapping the motor off the stand.

I went home.

This morning I returned and cut up some steel to hold the crankshaft:

http://forums.pelicanparts.com/uploa...1458271458.jpg

Then I threw on the 1 13/16" socket, heated up the nut for a minute and blasted it off with the air impact.

http://forums.pelicanparts.com/uploa...1458271614.jpg

The right side came apart with the specialty tools just fine after that. Moved on to removing the chain housings.

http://forums.pelicanparts.com/uploa...1458271825.jpg

?: Do the housings utilize a location dowel (or pin) from the factory, or is that case work someone else modified?

Not that it's relevant... but here are the plugs I pulled.

http://forums.pelicanparts.com/uploa...1458272162.jpg

After removing the cam housings... I found this on the 1st cylinder:

http://forums.pelicanparts.com/uploa...1458271925.jpg

Things looked okay, albeit grimy, everywhere else.

http://forums.pelicanparts.com/uploa...1458272057.jpg

http://forums.pelicanparts.com/uploa...1458272134.jpg

Last thing..
 

I pulled off cylinder #6 before leaving. Here's what it looked like:

http://forums.pelicanparts.com/uploa...1458272325.jpg

And at the case:

http://forums.pelicanparts.com/uploa...1458272365.jpg

I have not ever been fond of the crows foot either

Anyone..
Comments on chain housing locating dowels in case and cylinder 1 damage?

Got the rest of the cylinders and pistons out prior to travels. Time to start getting quotes for machining.

Got an answer to the housing dowel question from a knowledgable machinist; locating dowels are factory on the chain covers. The current plan is that some time next week I'll have everything prepared for the journey to the machine shop. I figured I'd save myself a couple hundred dollars and remove the exhaust and head studs myself. Snap-On doesn't have stock on the necessary collets with the remover tool, so I picked up a full used set on eBay.

http://forums.pelicanparts.com/uploa...1459218340.jpg

It's nice that the older Snap-On stuff came in metal boxes. I guess everything is plastic these days..

I like their ratchets and specialty tools but the rest of the current Strap-On stuff is not equal to what they once offered.

http://forums.pelicanparts.com/uploa...1459824768.jpg

http://forums.pelicanparts.com/uploa...1459824794.jpg

With the head studs removed and all of the case bolts & nuts off, it's time to head to the machine shop tomorrow to have an in-depth discussion regarding case and head work, p&c's, and 964 cam grinds.

http://forums.pelicanparts.com/uploa...1459825636.jpg

How much does rebuilding tensioners and updating idler arms cost these days ?

I vote yes on shuffle pinning any mag case bigger than 2.4, and I think the expense of the pressure fed tensioners is not worth it. Use 930 tensioners with proper spacers and new ramps, use 60W oil in the tensioners and pre-bleed.
Every bit as reliable as the pressure fed. I've been running them for 20 years on my 2.7.
Upgrade the oil pump, do the pressure bypass upgrade but not the cam line restrictors.
Do you want to increase the power or just go back to stock?

2.7
 

Boy that brings back memories. I have a 2.7 in my 69 T. 206.5 hp at 6250 on the JWE dyno. Super fun car. But I took the motor down to the crank 4 times to get it to stop leaking. My thoughts:

1) spend money on the cases. Have every stud time certed. Align bore it, shuffle pin it. Have the through bolt holes countersunk. I had Ollies do it. Taking it back apart for a pulled stud (say the oil cooler stud ) sucks. I went to 2.9 Andial P/Cs so they bored the cases to fit them too.

2) Use through bolts from the 3.0. The threads are finer and they torque up better. Use viton o-rings. Put silicon paste on the o-rings, and hold the washer with a vice grip and the bolt head with a wrench as you torque the through bolt nut so the washer and bolt don't spin. If they spin the o-ring(s) will twist into the case--especially as the mag cases work and the through bolt holes ovalize if not shuffle pinned. Pushing the o-ring in will result in a big leak. I pulled the through bolts out one by one and carefully installed the o-rings after I had torqued everything down once to get the case sealer properly set.

3) Use ARP or Henry's barrel studs. You'll be glad you did.

Have fun !!

I definitely have done. Here's a list of what's happening at the shop:

Timesert case, machining cylinder mounting surface, spot face through bolts, align bore, center two mains dowel pin, valve & valve guides, surface heads & exhaust flange, wrist pin bush, oil by-pass for late-style pump.

This is really useful information. I hadn't heard of utilizing the 3.0 through bolts.

ARP barrel studs is on this list already ;)

This is truly good to hear. I'm likely to save the cash and not splurge on all new timing covers.

I think the 964 cam grind and rebuilding the CIS is about all that's going to happen on this particular engine. I don't want to get too carried away from the stock motor so I can get a feeling for what the car was like from the factory.

http://forums.pelicanparts.com/uploa...1459983326.jpg


http://forums.pelicanparts.com/uploa...1459983354.jpg

I can say a few things with experience
The SC cams gave my 2.7 165lb TQ and 165 HP @ the rear wheels .
The difference beteen the stock engine and rebuilt was night and day!
There was more left as I had not yet hooked up the double plugs and it was running REALLY fat.
Now for the argument, I did eyebrow the jugs and boat tail the mains and did my own version of Port and polish .
If I had bumped the CR one point that would have made an another big difference but it was left stock.
So thats my advice, OR go wit the 964 Cams as they are even better !
If you can, bump it one point.
Pay atn to your squish margin

I'm interested in knowing more about this build as i'd like to do the same on my 1974.

Everything is at the machine shop, but I'm looking forward to the documenting I get to do when I go to pick it back up.

I've been indulging in the book that my machinist lent me when I dropped the 2.7 off:

http://forums.pelicanparts.com/uploa...1460942954.jpg

Typed this up for a friend who was curious, so here are a few *estimates*

Here are some *rough* numbers on the rebuild:

Machine work on magnesium case: $2,000.00
~ time-certs, machine cylinder mounting surface, spot face through bolts, oil bypass modification, check align bore, recondition connecting rods, clean & polish crankshaft, dowel pin center mains.

This would've been more expensive if we would've had to do more machining on the cylinders. I'm able to reuse all my Ps & Cs except one cylinder that was damaged, most likely from excessive head-slap from the case studs pulling. I was also given a replacement cylinder from a friend of my machinist. I also did all of the breakdown myself and will be doing the rebuilding myself ~ I was recommended a local hobby-ist who could give an extra hand during the more rigorous case-sealing and cam timing.

Parts for the rebuild: $6,000.00 ~ pretty much everything you can think of including all hardware, gaskets, nuts/bolts, late-style oil pump, turbo valve covers, updated idler arms, etc. etc.

Distributor re-bush/re-curve: $500.00, Cam regrinds: $400.00

I'll end up having the transmission gone through while swapping the motors, so that will be an additional chunk of change.

Just picked up on this thread with interest. My 2.7 has just been rebuilt but it is some way off going back in the car, as the shell is under restoration.

I have done all the mods mentioned, shuffle pinning, twin plug, higher compression etc. but with one exception, my oil pump has been left standard. It was checked thoroughly by a specialist, so my question is, should I be concerned? what advantages are there to be gained by fitting a different oil pump, read that some people are fitting a GT3 pump and is a good standard pump still up to the job?

I did not do the work on my 2.7 engine but the oil pump was upgraded to a 930 oil pump at $895 + shipping back in 2003.

So you did have the oil bypass modification performed by the machine shop, or not?

As per Bruce Anderson: "the oil bypass is a good idea even if you don't change the pump, because reducing the effort required of the scavenge pump keeps the oil level lower in the crankcase and reduces wasted horsepower."

I have no idea about performance of an early pump on a twin plug motor, but it sounds as though you are building a performance motor which may put additional stress on an oil pump designed for a motor with lower overall output/stress.

hey guys, i have a question. What would be the correct head studs for this engine? I know originally they were made so expansion of Nicasil will pull them out of the magnesium case...

i see couple discussions going here http://rennlist.com/forums/911-forum/1911-aps-vs-raceware.html and http://forums.pelicanparts.com/911-engine-rebuilding-forum/916428-2-7-hot-rod-rebuild-advice.html

Thank you in advance.

I used Supertec studs, but on a 2.7 many use stock steel studs.
On the mag cases the case itself is the weak point.

Reuse steel studs if in good condition, with time-certs of course.

http://forums.pelicanparts.com/uploa...1469497885.jpg

http://forums.pelicanparts.com/uploa...1469497927.jpg

Made a bit of forward progress finally. The garage has been 100-degrees plus, but I bit the bullet today and headed in for getting the rods on.

A few days later... still cleaning.
 

I did my due diligence and JB welded all of the factory plugs Wayne recommends covering.. I hate JB weld by the way, but I suppose in this instance it's recommended? Reminds me of an ex's nair products.. :o

http://forums.pelicanparts.com/uploa...1469919805.jpg

http://forums.pelicanparts.com/uploa...1469919996.jpg

Still trying to get to a point where I feel like the case mating surfaces are clean enough:

http://forums.pelicanparts.com/uploa...1469919323.jpg

I feel like I'm close.

I didn't want to hit it with anything more aggressive than the plastic scraper or plastic sponge, and the ultra-sonic cleaner did 90% of the heavy lifting. Still, there are impressions of the old gaskets and I'm comparing these surfaces to the mirror-like edges in the book. Maybe this is good enough..

Looks good!

This thread needs a bump... what's happened to the rebuild?

^ What he said! I know the case is back together... Update update! :-D

If only...
 

If only I hadn't bought another 911, and then reluctantly sent it away.
If only there wasn't a SWB 912 after that.
If only I wasn't in the midst of surgery on that 912.

http://forums.pelicanparts.com/uploa...1491509333.jpg

http://forums.pelicanparts.com/uploa...1491509333.jpg

If only I hadn't gone to Italy and Mexico.
If only I was further along with this build!

But, yes indeed the case is together.

http://forums.pelicanparts.com/uploa...1491509392.jpg

http://forums.pelicanparts.com/uploa...1491509392.jpg

http://forums.pelicanparts.com/uploa...1491509392.jpg

http://forums.pelicanparts.com/uploa...1491509522.jpg

Installed head bolts after wire brushing and clear coating w/ hi-temp paint.

http://forums.pelicanparts.com/uploa...1491509671.jpg

http://forums.pelicanparts.com/uploa...1491509538.jpg

And thank goodness for the continued use of the Snap-On collet stud tool.

Bumpage

http://forums.pelicanparts.com/uploa...1499045792.jpg

I wish I had more to report, but we just purchased a property where I'll be moving my shop so mostly this project is on hiatus. Although, I did finalize the last few items I required for the remaining top end, etc.

Hopefully wrenching again towards the end of July.

Happy 4th everyone!