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

[dangerousdave]

Re: A racing bmw 316, 240bhp Atmo M10

Could you not turn up a spacer that goes in between the prop and the diff flange and has the groove in to run the alternator belt? I have a pic of the audi one somewhere, its mounted inside the car above the diff tunnel

[Graham]

Re: A racing bmw 316, 240bhp Atmo M10

wish i could but the prop/diff flange sits inside a tunnel that passes through the rear x member,

so i shall just do similar between the diff flange and driveshaft, i figure as long as i have a 1:3 or higher ratio between the drive shaft flange speed and the alternator it will charge above pitlane / paddock speeds, to be honest im not really concerned as to how well it charges i just want to comply with the regulations!

we have proved ( by accident) on the rolling road you can run the battery down to the point where it wont start the engine and yet the mixture and power remains uneffected, obviously the volt drop correction map must be spot on

[Graham]

Re: A racing bmw 316, 240bhp Atmo M10

the pulley on the alternator is actually two pieces, it contains a cush drive just like a bikes rear sprocket assembly, so i threw one half away and turned down an alternator pulley to fit in its place

[david_white]

Re: A racing bmw 316, 240bhp Atmo M10

That looks good graham, wouldn't mind a bike alternator for mine and more so for Andys escort.

I do have quite a bit of room under my car and running the alternator under there would certainly make the engine bay tidier, especially as I'd like to go with an electric water pump like yours.
Only trouble is I do have a habit of ripping things off of the bottom of the car so it depends if the rules state that you also need to finish the race with an alternator

[Graham]

Re: A racing bmw 316, 240bhp Atmo M10

its blue book regulations, the just say car must be fitted with a working generator

[Pushrod King]

Re: A racing bmw 316, 240bhp Atmo M10

its blue book regulations, the just say car must be fitted with a working generator

Up until last week end the only DNF that I'd had was due to having an alternator which is why I took mine off and bought/fitted a power grip kit

[dangerousdave]

Re: A racing bmw 316, 240bhp Atmo M10

Can you not just fit a small petrol generator in the boot?

[stephen bahr]

Re: A racing bmw 316, 240bhp Atmo M10

small petrol generator would require combustion to work, not ideal when sat next to 50 ltrs of fuel

[dangerousdave]

Re: A racing bmw 316, 240bhp Atmo M10

The rules dont say it needs to be working when racing, just that it must be fitted with one that works.....it does work if you put petrol in and start it?

[Graham]

Re: A racing bmw 316, 240bhp Atmo M10

so onto snett,

the lead up to it didnt go well, my daughter got swine flu, so for some strange rreason she got all the attension and the car none,

which mean my prep for sundays trip to snett didnt start until saturday afternoon and all i really wanted t do was sleep,

no good, especially as the main reason for going to snett was to try out a lower diff ratio, the diff still sitting on the bench with the old ratio in it, fortunatly i had remembered to order some new crown wheel bolts

so it was a quick strip of diff, and swap the cwp, when disater struck, stupidly i put the insert down on a dirty part of the bench and when i picked it up again there was swarf all over one of the diff bearings , ok no big deal, a quick wash in the parts washer, that didnt go to plan either, with the swarf and lubricant washed off all the rollers feel out the bearing , much faffing around later with my sons help i had managed to get all the rollers back ther cage and back on the diff and it was all put together, and an hour later it was all back in the car

then i remebered the cut out switch had thrown a wobbly at silverstone and needed replacing, thankfully i have spares,

a quick check over at the front end showed a front wheel bearing was dying, panic statitions now, its 7.30 pm saturady night, not a cat in hells chance of getting a new one, then i remebered something, i had replaced the bearings, somewhere i had the old bearing which the car came with on an old strut, fortunatly the old bearing came off the strut in once piece (which is rare) and it went back on the car.

just to recap i was going to snett to see how the car liked a lower diff ratio, basically i just wanted to know the revs it would pull down the straight, i ws hoping a lower diff would allow it to pull a few more mph, noticable at the two fast circuits i've done this year is that it doesnt feel happy to really rev out in 4th or 5th, i know barn door areo dynamics are a major factor here but it just feels to be struggling. so lap times werent important but would of been interesting, my best non turbo lap of snett was in the old bmw 2002 with 1.22sec, that car was lighter but with less power, but done on a warm day, it was quite a cold morning which wouldnt go well for my tyres.

practice, off i went, exiting the pit lane the car felt good, it certainly pulled harder, down the back straight it certainly reved out much easier in 4th and was pulling to about 7k in 5th, of more concern though was everytime i entered the esses at the end of revitt straight my classes steamed up and i couldnt see where i was going, pulling them off and stuffing them between my legs didnt really help, my eyes need a little while to adjust to not wearing them plus the soon dissappeared into the footwell, pulling into the pits a got a marshall to retreve them only he couldnt see them so i went out again for another few laps.

back in the paddock stephen found my glasses in the footwel and i had a quick look over the engine, in particular there appeared to be fuel on the fuel rail and around teh bulkhead behind no4 intake trumpet, it was fuel, fortunatly it was a cold morning so it haddnt evapourated, we assumed it was a leak, but running the pumps showed no leaks



then it hit me, it wasnt a fuel leak but at the top end the air rushing through the engine bay was dragging some of the fuel back, probably slightly starving the front cylinder of fuel and possibly over fuelling the middle ones and leaving the rear one about right, time to go raiding dustbinS



here we go a wind deflecter made from a bit of old halfords sign,

id qualified with a 1min 23 something, which was ok, bearing in mind the temeperature and my vision issues, i was just ahead of john chasey (caterham 7) and just behind pete reeve (yb powered tvr) who i both had good races against at lydden, i knew i could get the better of the caterham but the tvr was going to be hard work as i was going to have difficultly staying with turbo yb power down the straight.

off the start in race one i pretty much held my own and could just hang on to the tail of the tvr down the straight, the car feeling stronger at the top end following the addition of the halfords wind deflector exiting russle chicane for te second time hard on the tvrs tail i grabbed 3rd and found a box full of neutrals still i could take comfort from teh fact things were moving in teh right direction and a 1.25 lap on only my second lap on cold tyres wasnt to be sniffed at

it turns out the gearlinkage remote stabalizer/support had snapped, a fatigue failure, a pukka race part i had bought some years ago, the bit that broke was a male thread cut (not rolled) into an aluminium shaft


after some head scratching i bodged something up so i could make race 2, we were last race of the day due out at 5pm, but the meeting was running late, it was getting preety dark as we hit the track, and the tempurature was now quite cool, too cool for my tyres to work properly,and i was at the back of the grid but it was a race and i had to go for it, with a very hit or miss 3rd gear selection i struggled for a few laps on i was back to having my glasses steam up and the tyres really didnt want to know and i elected to just bring bring the car home in one piece, well i did untill john chasey spun his caterham and i passed him, i then had a race again, through teh high speed corners i had no answer, but as i found it didnt matter, even if he was infornt of me at teh chicane before the finish linbe i could out accerate hiim and retake the position before the line, having raced against john before i now know just to what effect the ratio change has had on acceration, i always had a quicker car in a straight liine but not to that extent.

so another finsh, again not a great lap time another 1min 23 but in the conditions it was a good one and faster than a lot of the field, the ratio change worked well, i seemed of gained about 4-5 mph top end and a much faster accerating car,

i've had my first mechanical dnf of the year, not bad after 19races, 10 practise sessions and a test day.

im next off to brands in two weeks, preying for a warm dry sunny day as i have a mathametical chance of a 2nd in class in DMN championship

[david_white]

Re: A racing bmw 316, 240bhp Atmo M10

Good write up Graham, sounds like you had a busy day, to say the least.

Will the box be good again for Brands? If so I think the other class C cars will have a real fight on their hands now that you have a better diff ratio

With your injectors, how would they work if fitted into a cold air box? Surely the ram air effect would also disturb the spray pattern sending fuel away from cyl 1

[Graham]

Re: A racing bmw 316, 240bhp Atmo M10

the box will be fine, i just need to modify the linkage.

I think the other class C cars will have a real fight on their hands now that you have a better diff ratio

maybe, my tyres are pretty much on ther last legs now and the weather and temp are going to have a major effect, if its warm and dry i think i stand a chance,


i dont think an air box would hurt because it has a back to it there wouldnt be a 120m
mph wind being able to blow straight across and away from the open intakes.

the old 2002 was fine in that respect the only difference betwen this and that was the 02 had a pipercross filter like yours and teh injectors stuck through it

[mervhill]

Re: A racing bmw 316, 240bhp Atmo M10

Crikey Graham, you don't do things by 'alves do you?

Hope it goes well at Brands. One consolation of tyres being nearly buggered is a new set for next year I guess!

[Pushrod King]

Re: A racing bmw 316, 240bhp Atmo M10

Forecast for sat: http://www.metcheck.com/V40/UK/FREE/...h=10&year=2009 and sunday http://www.metcheck.com/V40/UK/FREE/...h=11&year=2009.

Hope it changes

[david_white]

Re: A racing bmw 316, 240bhp Atmo M10

How comes you had trouble with your glasses Graham?

Oh and forgot to say hope your daughter is better now, there is a lot of that shit going round at the moment