A race bmw 316, m10, s14, m20, turbo, na, its been the lot!

[Tristan]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

I thought that it was the butterfly angling the airflow in the direction of the valve?

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

it can be.

anyway made a bit more progress, took bloody hours thou, i shimmed up the top end, i really wanted to go group a top hat shims as opposed to shim in bucket, but with costs going out of control its really not an option, the inlet cam is the max you can use without going top hat and the exhaust is one milder so fingers crossed so in theory it would of been overkill but a good safety margin



i chucked the retainers up and turned 1mm of the base to give clearance to the stem seals, it was only needed on the inlet but i did them all anyway, saved 1 gram of weight too


first off just a quick check to see the valves all protruded the same give or take a few thou


dropped in the inlet cam only to find it wouldnt turn as the lobes fouled the cam carrier so a little more grinding was required



rooting through my spares i found a complete set of buckets and shims from a 24v e36 evo, they make a good drop in replacement for e30 ones, the bucket itself is lighter and uses a much thinner shim, giving 26 grams or 33% weight saving.


having meassured up all 24 e36 shims i found there were only 3 sizes, even the thinnest was to thick so i used the thinnest ones and shortened the valves a tad to get the clearances right, my valve facing machine cant shorten valves but a grind stone in the lathe does a good job, the beauty of starting with thin shims was that if i got it wrong and took a fraction too much off i always had a thicker shim to fall back on

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

i've moved onto valve springs now, lots of people use the schrick cams i have with std springs, obviously shrick recomend you use theres, e30 evo3 springs are recomended by quite a few people, i have neither evo nor schrick springs, but what i did have was a huge load of used std s14 springs,




so i decided to use what i have and select the best 16springs, without a spring tester the mill and a set of bathroom scales had to suffice, basically i set a stop so the springs were compressed to near coil bound and the scales read, the bigger outer springs varied from 60kgs to 66 and the inners 24 or 25 with a couple of really strong ones with 28kgs.
i went round all the springs several times to make sure i used the strongest





especially with the lighter e36 buckets and shims i recon i wont have any issues with springs as i'll have around 190lb nose pressure

[david_white]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

Great ingenuity there, I was gonna ask you if you had a proper spring poundage tester as I think we have used the corner weight gauge before. Looks like the results you got were useful and better still, repeatable, which is all you need. Looks like you have some spares still too

Pity stuff like the timing chain blades are so expensive as you look like you are flying through the build now..

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

i had a productive afternoon too

i got teh block back the other day after having it decked,

started out gapping the rings, with not many rings i kept the gaps down towards the bottom end of the tolerance specified by wossner



i get a bit of a surprise when i fitted the first piston assembly, turning the crank the engine locked up! i was confused for a bit, the crank and bearings were fine, nothing fouled, but still it would lock up, a strange lock up though it didn't have the solid sort of stop that you normally get when something hits it felt more like a seizure, the crank and pistons had previously been in the block without any problem, in the end i sussed it, the only difference between now and previous times is ive now fitted the rings, the added friction meaning the very short skirt on the pistons rock in the bores and top edge of the crown locks against the bore, its prob not helped by the rod stroke ratio being less than ideal 91 stroke/ 144mm rod, but i never had issues all the time i ran 87stroke/ 134 rod which is a worse ratio, so i was pretty sure its just piston design, i stood there thinking this things going to be a right bastard to start if its going to stop dead every half revolution, some oil down the bores helped,i carried on turning it over with a long screwdriver between a couple of flywheel bolts watching the pistons rock, then i discovered something, it only does it if you turn it over slowly, turn it faster ( well as fast as you can with a screwdriver in the flywheel bolts) and it spins over ok



now i decided to tackle the issue i had with regards as to the effect the piston dome had on the CR, i knew roughly the effect the piston should have having worked backwards from wossners catalog last time i tried to work out the effect i kept getting different results, not just different results but they didnt tally with the theory based on the catalog,

im pretty sure the issue was just i couldnt seal the piston well enough, with rings fitted it was time to have another go, not wanting to put water or degreaser into the bores (i didnt want to take the pistons out again) so i opted to use ATF in the bureette, a good move ATF is very easy to see and thick enough not to leak away, and as its oil no problem with any of it getting left behind finally i got the answer that i expected, the pistons neutral compression wise, the valve cutouts offsetting the intruder


put the valves in next, the springs retainers and valves etc all got a wash in some very expensive cleaning fluid ( old race fuel)
the head went in a domestic appliance! dont tell karen though or she'll never eat or drink here again lol!



having put the valves in time to do another bit of bureetting, i'd already done it but the head has been skimmed since, suprsingly considering its over the years had quiet a bit taken off it its only 1cc bigger than std, i guess valve seat cutting has dropped the valves back and offset things.



so now i can finally know what the CR will actually be, with the thin gasket i'll have 12.3:1, i could easily get some more, but as previously said i'd prefer not to skim more than nec off anything, in anycase i am only using 292 degree cam so 12.3 is prob plenty

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

more bits arrived not sure they are £420's worth thou

[stephen bahr]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

i had a productive afternoon too
the head went in a domestic appliance! dont tell karen though or she'll never eat or drink here again lol!

well fat and grease etc clog the dishwasher, so having a nice clean run probably helped it
and you can't put parts on your nice table, that's what the pool table was for

[M11rf]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

£420 Are they made from gold?

[caprimentle]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

christ almighty, £420 quid for them! i'm in the wrong line of business

nice idea on the springs, is thier any way to make them stronger by the process of heating then quenching in oil, then heating and cooling constantly to try and get out as much oil as possible, as far as i know thats the way they make leaf springs so they are flexible yet tough. i seem to remember being told how they make leaf springs but i was only 15 at the time

[team_zi]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

I still love reading this thread. I can keep up with most of the technical stuff, but you take engine building to another level, Graham, its almost an art form.
And you keep this thread fully updated. I don't know how you find the time.

[team_zi]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

£420 Are they made from gold?

It think its because they're mounted on a giant piece of oak.

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

It think its because they're mounted on a giant piece of oak.

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

I still love reading this thread. I can keep up with most of the technical stuff, but you take engine building to another level, Graham, its almost an art form.
And you keep this thread fully updated. I don't know how you find the time.

from you sir thats a big compliment ! i only wish i had the time and more so the patients to make everything as nice as you do

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

came home to find this had arrived



i just love the service you get from mike at ferriday, custom gasket sized to suit my particular engine from phone call to drawing board and delivered in a couple of days

i could of stuck with a std bmw gasket but i know the chances of this failing are very slim, also keeping the std gasket would of meant loosing over a ratio and half off the compression or skimming another 0.040 off the block

so unless i've forgotten something thats everything i need to assemble the engine this weekend

[Graham]

Re: A race bmw 316, 240bhp Atmo M10 now going s14 power!

latest ebay purchase, cost me all of about £3

its a demister for an e30 convertable i think they actually had two but this will do for now, its got its own built in heating element which has a built in bymetalic strip switch so it cant get too hot, the motor doesnt have a huge amount of puff but the heat output seems very reasonable for the units size