Bean Bandits Levin 'Globetrotter'

[Bean]

oldeskewltoy Wrote:

DETAILS -
static CR?
Valve reliefs for stock valves?

Is this a custom piston, or to your specifications? Got a piston job # to share so we can order similar pistons??

to my specifications...
CR=11.43; Piston Volume 3.5cc; valve reliefs: for stock diameter but more lift; compression height 30mm (instead of 30.5)
which in my case results in a DCR between 8.5 and 9ish depending on headgasket and block shaving

Price: 720$ incl. pins, rings, locks, coated skirts and shipping (within the US) through BC (strange enough directly from JE for the same exact pistons would have been 1k+)

I have to look at the paperwork that was supplied with it, as BC said they wont provide any partnumber to recreate it but think JE did

oh and bore is 81.5mm

I have to say they look very well - as I was a bit scared ordering them through BC (acting as a middle man) but am pleasently surprised about the outcome. The dome is nice and flat compared to say Wiseco, no sharp edges and I can't see any imperfections on the one piston I checked so far.

The only slight odd thing is the skirt on the exhaust side is narrower than the intake side. This design will make them clear the oilsquirters and make notching the squirt redundant. You might remember my worries there. Will they last? only time will tell but for the price I payed I can't complain so far.

EDIT: communication with BC was good and they realized that the skirts weren't coated when first shipped to them so sent them back. Unfortunately the resulting delay caused a slight inconvenience on my part as all the parts needed sending on to me. Therefor I wasn't able to get my crank balanced by my friend (works in aviation and their tolerances blow your mind, last crank was 3μg (yup MICRO) @9000rpm, his machine doesn't run any lower ) and have to find someone local now. That's not their fault though and I'm glad all the parts arrived in time for me to take them back here.

Thanks again mate - couldn't have done it without you (will send you a treat early August, once I'm back at work)!

[oldeskewltoy]

If I may.........

using painters tape... tape up the skirts, and the ring areas 1/2 way up between the pistons edge, and the first ring land. Then take either a firm knitted nylon scrubber, or similar "roughing tool" (I'd use Dremel puffs... the softest[dark blue/dark grey]) and gently work the pistons crowns. Anywhere there is a machined edge... just "knock it down".

[Bean]

oldeskewltoy Wrote:If I may.........

using painters tape... tape up the skirts, and the ring areas 1/2 way up between the pistons edge, and the first ring land. Then take either a firm knitted nylon scrubber, or similar "roughing tool" (I'd use Dremel puffs... the softest[dark blue/dark grey]) and gently work the pistons crowns. Anywhere there is a machined edge... just "knock it down".

Good call, fortunately JE did that already :wink: - hard to see in the pic as I was in a hurry when I took them.

[Bean]

oldeskewltoy Wrote:Got a piston job # to share so we can order similar pistons??

found the paperwork and will scan it once I'm back at work. The numbers and all are on there not sure if they would allow anyone to get a copy though. Also as mentioned before, for some strange reason it's cheaper to order the JE piston set through BrianCrower than direct.

[Bean]

here you go:


as mentioned depending on how much the block has been shaved, headgasket thickness and head cc the CR can be anywhere from 11-12:1

in my case with a deckheight of 0.5, head cc of 36.75cc I can alter CR from 10.5-11.43 with the corresponding headgasket of 0.5-1.2mm

I need this range due to my current lack of high grade fuel so I can keep my DCR in check with the current cams (dynamic stroke of 61.9mm)
I might opt for a wilder cam in the future (dynamic stroke of 58.8mm) and then I can safely go for a thiner (0.5) HG to push DCR back up to 9:1

[Apolan]

Bean Bandit Wrote:and here a better side by side picture of the water bypass (old->new)

Funny how seeing a tiny part like this has such strong memories bounded to me old memmories of working on the 86.. god i miss her

[Bean]

slow progress: started measuring the valve clearance



exhaust side is done once, will do the intake next week and then both again to be sure

[Bean]

after quite a long brake on working on cars in general I forgot how much of a pita some of the jobs are...
small advice on measuring clearances, make sure the assembly is seated well (i.e. turn the cam a couple of times).

I have measured the exhaust side twice now and found different measurements on cylinder 1 and 4 so will continue tomorrow with the intake side. Then come back to the exhaust side once more.
Only when I measured both sides twice to the same results (after turning the cams a few rounds) I will be satisfied and order the correct lifters.

As the old proverb says 'measure twice cut once'

PS: so far the range on the lifters is from 5.4 to 5.64 (5.68 is the thickest available) - phew on that.
If I'd could go back in time I would have gone the extra mile and supplied the machine-shop, who did the 3-angle job, with all necessary parts to equalize lengths. That way shimming would have been a breeze as then all lifters would have been the same.
We live and learn.

[Bean]

So after more than a thousand days since I started this thread... it's far from being finished

I finally found a local machine shop, took about half a year give or take some months. They have some decent enough machinery to complete the job to my minimum standards, as long as I watch/supervise/check every step they do BUT and that's a big one - they lack precise enough measurement tools to adjust those machines

I get the feeling some higher power is against me to complete this engine any time soon.

So at the moment I'm doing research where I can buy/borrow the necessary tools. I found some options in the buying category but those micrometers aren't exactly cheap, especially those accurate to 1/1000 of a mm
Found a calliper made by Sylvac which is better priced but not exactly the right tool for the job, so will keep looking and go on a weekend trip out of this hole before I make a decision.

[Bean]

Some good new for a change

my crank just landed back in Switzerland and is off to a mate of mine to be properly balanced on his over the top machine (aviation company) and will be back just before X-mas.

The block will get it's machining done within the next 4 weeks too.

Still need to order in a few bits like bearings, the final lifters, new brake pads, injectors and so forth but the biggest wall has been teared down

Bearing sizing will be done in a two step process, meaning I'll order the smallest available, measure with PL-X and then order the right ones (same process as with the lifters). The redundant bearings will be scrap but still way cheaper than a set of micrometer (with 0.001mm accuracy).

So if nothing else comes up again, I should have it all together in January

Then the headaches of tuning will start, as there is no such thing as a dyno anywhere close.

PS: oh and making an airbox and stacks but that's just a matter of me getting my arse in gear.