The 2.7 arrives, build advice.

[cnwayland]

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:

[cnwayland]

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.

[rgruppey]

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?

[zedsn]

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.

[cnwayland]

Originally Posted by rgruppey

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?

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.

[1-ev.com]

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 2.7 Hot Rod rebuild advice.

Thank you in advance.

[Mark Henry]

Originally Posted by 1-ev.com

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 APS vs. Raceware - Rennlist Discussion Forums and 2.7 Hot Rod rebuild advice.

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.

[cnwayland]

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

[cnwayland]

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.

[cnwayland]

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..





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



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..

[cnwayland]

[Evan K.]

Looks good!

[mikedsilva]

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

[75 911s]

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

[cnwayland]

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.





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.









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





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

[75 911s]

Bumpage

[cnwayland]

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!