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Building the 8000 rpm 3.2 for my race car:


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Had a busy day in the gaage. with no engine parts in sight I turned to the oil system and removed and cleaned the cooler and the huge dry sump tank.
Car was very dirty when they were removed, but everything good now.

It was with some trepidation I split the dry sump tank to see what was in the bottom after 5 years use. Swarf, bits of steel, shards of aluminium?

Nope, clean as a whistle, so chuffed.
This was a very good engine!

Dirty:

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Dry sump apart:

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Together again:

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Cooler, cleaned and back in. So much dirt trapped in the cooling fins!

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  • 2 weeks later...
finally, a bit of garage action.

Got my heads back from The Head Shop in Warrington who have machined them for twin plugs.
Great to deal with, promised 3 weeks and a good price, ready by 3 weeks at the same price, no surprises, price quoted inc VAT, what a refreshing change.

Bought a nice new valve lapping stick with supple rubber cups so grip these huge valves, and after clearing the carbon from the exhaust ports and re-fitting some studs (removed to access the area for machining) finally ground the valves on one head, set the small temporary springs to hold the valves tight and all fitted to the heads with shim-less assembly but the titanium top caps to measure the height for the racing springs.
This method works a treat, no fancy £110 tools, just 2 simple springs, £2.00 each. :)

With the tension on the two valves, 2 plugs in tight, inverted the head and filled the combustion chamber with white spirit to wait for leaks. One drop came free after 35 mins when a fellwe DDK'r arrived!

Drained the spirit off and measured the distance from the underside of the top cup and the lower spring seat.

For the springs I need close to 36mm on both valves, so by adding the right number of shims managed to get to 35.8 and 36.2mm. Can't get closer as the shims are in 0.5mm thickness only.

Springs in tomorrow and that will be one head done, 5 to go.

My main crank bearings and chains cleared Customs today, so they will be with me end of next week.
Another long wait then for the pistons and rods.

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Woke up this morning to a day to myself due to weather keeping us indoors ( :) )

Set about doing all 6 heads all ready to go on the engine, so once the smells have dispersed they will migrate to the 3rd bedroom... :bom:

Methodically did the following
Lap the valves, fit the temporary springs to both valves, fill combustion chamber to the top with white spirit, pause a few mins and check for leaks (none!)
Drain, measure the distance to fit springs with digital Vernier, calculate the shims needed to get close as possible to 36mm. Managed this exactly twice.

Strip, oil valve stem and insert, fit guide seal nice and snug using the tube sleeve provided to prevent lip seal damage, remove sleeve.

Fit springs and titanium top hats. The collets were a test, but the last of the 12 I did flew together :lol:
Using my motorcycle valve spring compressor is a darling, so light and easy, highly recommended.

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Had the great fortune to attend the Midland Hill climb Championship Awards bash last night with about 140 others, all dressed-up in posh rags, barely recognised anyone!

We started doing the Championship in 1992 maybe '93, in my old 911, the one I still have.

So many trophies were handed out to winners and people who support this Championship and hillclimbing in general, some needed a lorry to take their stash home.

Some classes have a dedicated award with history behind them and another to keep, the boxes pile up fast.

We have had a great season. The car has been perfect, even the driver operated it well on a few occasions, and seeing as I never won the class once we managed to lift the Class Win for the 4th time in 29 years, all wins with the lovely Lola-Porsche.We have had all these years with great class mates, some I've known for 30 years and all add so much richness to the weekends.
We have done 9 meetings and the fabulous PCGB Porsche day at Prescott.

Seeing as we always turned up the few points we won gathered pace and as several (all) the class registered runners only did a few of the meetings, we won through.

So, Class win #4.

Never 29 years ago did I dream this would happen.
Hard work and a touch of perseverance and a totally supportive wife sure reaps rewards.

I should add another DDK member took home an awful lot of awards, he might tell his story.

I hope you will forgive a few moments of Bragging Rights. :drunken:

And a few pictures from the year:

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Thank you all for your comments.

It is a fabulous little club racing car and the 908 was the inspiration when I found the engine just after finding the car.

It nearly got a Rover V8 and very nearly a simple Pinto engine, but so pleased to bag this top fan 911 flat six.

 

getting these class wins makes all the difference to motivation and money/time spend, this though will be the last iteration of the car in my hands, hence the investment for a Grand Finale!

Hope the Pistons and rods arrive before Xmas, the engine must be fully running by mid March.

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On 07/12/2021 at 13:40, 911hillclimber said:

getting these class wins makes all the difference to motivation and money/time spend, this though will be the last iteration of the car in my hands, hence the investment for a Grand Finale!

Graham, I posted my congratulations to you on Uphillracers, but congratulations again. Will try and introduce myself in 2022.

The other Nige

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Please do!

Rare to meet people off the internet at venues.

My rods are in the country, but having to prise them out of the supplier's UK facility (!)

If I can get them soon I can build the short block while waiting for the pistons which seem to be never arriving.

Soon, i will be up against it on time for the season 2022.

 

Gearbox back from Greatworth Classics, Done in 4 days and cheaper than quoted as the job was quicker on my particular box.

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  • 2 weeks later...
Time to get going on this little engine.

The debate about how to measure to 1 thou the stretch of the con rod bolts is resolved, I will use my digital verniers.
They give easy access and (in my hands) a repeatable result, despite my nerves.

I did 'make' a dti gauge like those sold all over the USA and used by the professionals, but I find them clumsy.

I've washed the crank, poked and washed the oilways with proper oil way brushes and carb/brake cleaner rattle can.
Dowsed the thing in WD40 after mounting it on the old flywheel.

The rod bolts need a 1/2" 12 point socket and I only have metric, too loose @ 13mm. A mate is bringing a selection of 1/2" for me to try later this week (ex Snap-On dealer).

The lower crank case has been cleaned 5 times using brake cleaner, oil drillings brushes and a scriber. All old sealant is off and all flushed out.

Black bin bags all cover the parts ready for an assembly. I expect to do the rods/crank Thursday and lay the crank/inter shaft and chains in the new mains after Xmas.

As to bonding the cases, that will be between Xmas and NY when I have the day clear in the garage.

The garage is getting as messy as Rob's!

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Time to crack on a bit with this engine.

Have all the bits, the tools and with my head clear, time for the rod installation.
Never done this before, so a bit new, but quite straightforward save for a few things...
The Carrillo bolts are pre-assembled to the rods, so they all needed cracking loose and one by one removed. I weighed the rods.
They are all within 0.5 gram of each other.

Mounted the crank on an old flywheel horizontal in the vice. I think this was a good move.

Cleaned the first rod journal, the rod faces and he new shell faces, assembled the lot with a nice smear of assy lube and snugged the freshly greased bolts to 12 lbft.
Rods slipped round the crank a treat.

With my home modified DTI, set the gauge to Zero and the limit markers to Zero and 0.170mm, the amount the bolt has to be stretched to.

One bolt at a time applied the torque (wrench set at 75 lbft) with a fresh 1/2" 12 point socket. The torque level to reach this stretch is considerable.

In 3 steps got to 0.17mm stretch. Quite hard work!
Second bolt on the same rod, again a fight to get 0.17mm, only 10 more to go!

Eventually got all on the crank and all at 0.16/0.17 mm finally resorting to a LONG breaker bar and judgement.

Watched a video the other day and the tech said make sure you are strong enough to do the job. Now I know what he meant.

Job done and all rods slip round the crank.
Used up 3 sockets in this, the new Sealey one lasted 3 bolts, 2 others a further 3, and my old Britool 1/2 finished the rest off with ease. It is of course British made and 50 years old.

Have to say, pleased that is over with.

Case assembly next.

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Big step today, the build of the short block, 4th time for me, still makes me nervous.

Preparation and cleaning the order of the day, and all Boy Scout stuff, "Be Prepared".

Tools laid out and cleaned, all the bits required from the gasket set (which has an excess of some O rings), fresh sealants, cleaner, sockets sets and cleaner.

Lots of work then The Moment and the clocks starts ticking, 40 mins to get it all up tight.

Went well, not much drama (that came later) and even felt I was a near expert, but far closer to dangerous with a little knowledge. Dempsey Handbook always there, great book to follow.

All fasteners tight and checked 3 times to torque, fiddly chain ramps in place and time to stand back and admire the architecture of the air cooled flat six, an engineers dream. :drunken:
With everything tight, time to turn the crank, hopefully more than 720 degrees.

Fat chance as the crank came to a very hard stop after 45 degrees. What a horror, first thought was the one con rod was hitting the oil pump (you can get that scenario if you change to a bigger pump).

Found #3 rod solid. Backed off the crank and the rod was free. Stared at it (no swearing oddly) and thought I would hold #3 in it's correct position, ie about the centre line of the bore as if with it's piston.

Crank moved freely, 5 revs and all is well and SO VERY SMOOTH.

Decided to suspend the rods with elastic bands as noted on an engine rebuild at Greatworth Classics at the Autojumble. All rods now 'on centre' and the crank is beautiful.
Flywheel on with ARP bolts and all the right potions for assembly to 70 LbFt.

So, the end of a day, great to get this one done too.
Just need some pistons for the fun to continue.

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Good work Graham,  yes,  keep the thread going.

I can’t believe how many parts and what a faff building a 911 engine is,  it’s just and engine with crankshaft, Conrad’s and pistons at the end of day,  “Shirley”.  😁

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Had a pass-out for this afternoon, so decided to check the squish 'height', crown height, and the rest of the ring gaps.

To the first, mounted the piston to the rod with #1 barrel and an old copper base gasket, then added 3 pea sized pellets of BlueTac on the sides of the piston dome and the very top with a smnall piece of cling film over the top so when crushed the bluTac would not stick to the piston.
Advanced the crank well over TDC.
Added the #1 head and torqued the lot to final spec, 26 lbft.
Rotated the crank until you feel the blutac being squashed and then over tdc for about 30 degrees.

Remove the head and measure the crushed BluTac with verniers.
Repeat for the RH side.

Results were 1.72mm and 1.76mm (doubt you can call the last digit accurate) Squish. So, about 70 thou. and the top was about 3mm!
I'm happy with that.

Thirdly, placed the top ring in all the other barrels and all need opening up from a gap of 12 thou to 15 thou, none larger.
JE spec is 17 thou min, the second ring is 4 to 8 thou wider.

Awaiting Peter's gap grinder before I can get serious.

Next step is to build up both sides dry and set the cam timing. (what joy) and then advance the inlet 80 thou via the rocker screw and rotate so carefully the crank 720 degrees to feel for interference.

If clear, drop the inlet back and do the same with the exhausts but to 100 thou and keep my fingers crossed....

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Managed some hours getting the engine to a dry build, ready for cam timing and valve interference test.
This too k ages, partly due to my stupidity.

I ordered the cams and forgot to tell them to delete the rear drive pots on the back of the cams as James had warned me. Forgot.

So, spent some time sawing the stubs off and levelling the back, bit nerve wracking on a pair of £1300 cam shafts, but all done. Cast iron is nice to cut!
Checked the fit of the woodruff key in the cams and found them too tight so out with the needle files and some carful thinning of the keys and all was well.

Built the cylinders up missing out #2 and #5 as not needed for this task.
Assembled each side with the engine on it's side so gravity was always keeping the chains in place and slowly got it all together, just the rockers in #1 and #4 heads to fit and I'm ready for endless fun with the DTI gauge.

However, for a bit of relaxation, helping a fellow DDK'r take his engine out of his 911 tomorrow. :)

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Spent several hours on the dry assembly to conclude it.

Got the cam timing of the GE60 to 5mm (range is 4.8 to 5.2) on both sides.
The LHS came on 5mm first setting! :shock:
The RHS came on 4.7mm and took several iterations to get to 5mm.

So far, so good, then the evil bit, checking the valve to piston gaps...

Started with the LHS inlet and clearance is 2.5mm (min is 1.5mm allowed) and thus lots of room.
RHS inlet was 2.35mm
LHS Exhaust was 3.25mm (2mm minimum allowed)
RHS Exhaust was 3.25mm

Phew, all ok and room to spare.

Will check it all over gain tomorrow and then tear the lot down.

Have the loan of a DDK ring gap grinder, so gapping all 12 rings next which will be a joy. :wink:

Just one pic covers 3 hours.

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