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Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 10:18 am
by vlad01
iirc the v6 crank one is 7.25" or something like that. So yours is probably all good then.
The stock V6 setup at 5600rpm redline just touches on the max alternator allowed rpm, so its perfectly matched from factory. Any higher rpm and technically you're over driving the alternator in this case.
Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 1:06 pm
by immortality
How often would a regular car see max RPM though? I honestly don't think it would be a problem and alternators need to be geared to suit around town idling conditions. You have the same issue with the idler pulley roller bearings, the smaller ones would exceed the maximum recommended speed of the bearing with the engine at red line. The odd rev isn't going to kill things, sustained rpm would be a different story.
Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 1:30 pm
by Holden202T
yeah thats it, might be more of an issue for a circuit track car, less of one for a drag car, as even when you do hit high rpms its only for a few seconds.
Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 2:30 pm
by vlad01
Not really a time thing, for all you know the fan might explode in the first ms of over revving or it might be a couple of min, you don't know when but every time you exceed it, it might let go.
I know of 2 people this has happen to on normal hotted up street cars and seen countless other ones including cooling fans on the net and not to mention all the clutch explosions when using weak OEM clutches on high rpm engines.
You have to remember its a g force thing, that means its squared with rpm. quick online calc says for 120mm wide fan at max rpm of 18k is 22,000 G, add 25% to the rpm and you get 35,000 G. That is almost 60% more Gs
Btw, I confirmed the balancer is 7" on the V6, so with 6" on the 202 you are pretty safe with the stock VR alternator.
Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 6:29 pm
by immortality
I've never personally seen one go.
Clutches are much bigger diameter and much more mass.
Re: FX Holden Race Car Project
Posted: Wed Dec 23, 2020 7:25 pm
by Gareth
I have raced in speedway most of my life.
I personally have experienced both a clutch explosion and an alternator fan explosion, neither are any good...

Re: FX Holden Race Car Project
Posted: Thu Dec 24, 2020 6:28 am
by Holden202T
So while the car was on its side i thought it might be the perfect opportunity to fit the fuel lines and rivet them to the chassis, certainly much easier doing it this way than lying on the ground!
Last night got a few muscles over to help put it back on its right side, we then proceeded to fit the diff.
All business under here!!
We also chucked the fuel system in the boot.
I now need to wash and paint the front control arms so they can go on, then theres a few small welding and grinding jobs i need to do on the front end of the car, so i'll probably try and sort them over the christmas break, also start fitting things like the shifter so i can drill the hole in the tunnel before the box goes in but shes slowly starting to come together!!

Re: FX Holden Race Car Project
Posted: Thu Dec 24, 2020 7:40 am
by Gampy
Looking pretty sweet ...
I just noticed you have a perimeter tube, that makes it hard to drop the cage through the base to weld the tops ... Unless done prior to install of perimeter tube.
However that also makes me question the andra rules or the interpretation of them on the use of base plates.
If you weld the cage directly to the perimeter tube you should not be required to use base plates, at least that's the way it is here ...
In the end, all that matters is if the driver is satisfied it's structurally sound and the andra technical inspector that inspects it, is satisfied.
Re: FX Holden Race Car Project
Posted: Thu Dec 24, 2020 10:01 am
by vlad01
Nice reference scale for the size of that fuel tank.
Re: FX Holden Race Car Project
Posted: Thu Dec 24, 2020 11:08 am
by Holden202T
Gampy wrote:Looking pretty sweet ...
I just noticed you have a perimeter tube, that makes it hard to drop the cage through the base to weld the tops ... Unless done prior to install of perimeter tube.
However that also makes me question the andra rules or the interpretation of them on the use of base plates.
If you weld the cage directly to the perimeter tube you should not be required to use base plates, at least that's the way it is here ...
In the end, all that matters is if the driver is satisfied it's structurally sound and the andra technical inspector that inspects it, is satisfied.
so when i started this car, the welded roll cage rules didnt allow it (or didnt specify) that it could be welded to the chassis, but recently they updated it to allow it, now the issue here is that the chassis member needs to be of the same thickness as the roll cage or thicker, which mine isn't, as its 2mm, and was only put there to replace very fucked out inner sills and also add some more strength..
had i have known back then that i could weld directly to the chassis i would have made them 4mm like the inner chassis rails and 4 link frame! i also would have welded the cage in then laid the floor around it, which would have also allowed me to drop it down to weld the tops ....
vlad01 wrote:Nice reference scale for the size of that fuel tank.
i knew i had to put reference in a picture or i'd be shot! ... i was going to put it in every pic somewhere strategic, but it was 9:45pm and i was over climbing under the car so just did the one
