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Re: Fake - F7R Motorsport Daily

Posted: 29 Jan 2012 08:45 pm
by Evoman
I did beleive that the weigth distribution is 50/50 or this only true for 340s? I cant imagine the springs have shrunk in width by 1mm. They could shrink becuase of the vertical loads (possions ratio etc) but 1mm would be a huge strain!

So the aim is to get the frequecys equal? or perhaps alittle higher at the back :P

Re: Fake - F7R Motorsport Daily

Posted: 29 Jan 2012 09:00 pm
by jtbo
Evoman wrote:I did beleive that the weigth distribution is 50/50 or this only true for 340s? I cant imagine the springs have shrunk in width by 1mm. They could shrink becuase of the vertical loads (possions ratio etc) but 1mm would be a huge strain!

So the aim is to get the frequecys equal? or perhaps alittle higher at the back :P
Equal or bit less at back as your driving wheels are rear and if you have equal then it starts to break rear out unprovoked already, if differential is locked it generally adds to understeer, but with power that can became oversteer quite quickly and then little lower spring rate at rear makes it bit easier to live with and trust so you can better use that potential in car.

Then one thing to consider is also level of grip when pulling out, braking etc. generally lower is more grip and higher is more control, so it is not quite as simple as getting 50/50 ratio.

I think that B200 models can't be quite 50/50, they have quite heavy lump at front after all, but until I find enough cheap scales (weight measurement devices, not fish kind of), I really don't know how it is with my 360.

Oh and 1mm measurement error would be surprisingly little for me, just so that you know how much to trust my measurements = very little :lol:

Re: Fake - F7R Motorsport Daily

Posted: 29 Jan 2012 09:05 pm
by Evoman
heheh, but its all very interesting :P If i was to high the NF of the front how could i do it? i have stiffer springs

Re: Fake - F7R Motorsport Daily

Posted: 29 Jan 2012 09:10 pm
by jtbo
Evoman wrote:heheh, but its all very interesting :P If i was to high the NF of the front how could i do it? i have stiffer springs
Stiffer rear springs or less stiff front springs, in your case I would consider adding another leaf to rear springs, something that is not as thick or not quite as wide, however attaching different width spring is bit of challenge as one should not drill the springs.

Re: Fake - F7R Motorsport Daily

Posted: 29 Jan 2012 09:19 pm
by jtbo
Evoman, take a look at this also, some background and good info there, imo:
http://www.timskelton.com/lightning/rac ... prings.htm

Re: Fake - F7R Motorsport Daily

Posted: 31 Jan 2012 01:33 pm
by foggyjames
I suspect the 50/50 figure relates only to the B14. The B172 isn't a lightweight. Lighter than a redblock, but not by very much. I reckon an F7P/R is around the same weight as an 8v redblock....just a hunch.

cheers

James

Re: Fake - F7R Motorsport Daily

Posted: 01 Feb 2012 07:22 am
by jtbo
In my memory there is 140-150kg for redblock's weight, but I have no idea if that is even near there. Actually I would need exact figures of that too, just don't have engine lift and big sea fish weighting equipment :lol:

I think that I did read tiny bit over 56% front weight percentage for redblock fuel injection model, but it was with rollcage and interior removed, race car that is. Earlier I had heard something around 53%, so there I have estimated it to be between 56 and 53% of front weight.

Some scale which would weight 300kg is something I could use, also engine lift too.

There is big wooden support beams in my garage, but I don't know if I could use such as mounting point for not so expensive winch (well, chain winch, what you call them?) with such I might be able to get estimate as I recondition my motor mounts, but I would still need scale and there is margin of error because clutch bellhousing and torque tube.

If I find two cheap 150kg scales I will buy them today, might get something worked out about this weight stuff then when weather eases up a bit, -28C is not temperature that I can work with (no heating in garage).

Re: Fake - F7R Motorsport Daily

Posted: 01 Feb 2012 10:24 am
by Chris_C
jtbo wrote:There is big wooden support beams in my garage, but I don't know if I could use such as mounting point for not so expensive winch (well, chain winch, what you call them?) with such I might be able to get estimate as I recondition my motor mounts, but I would still need scale and there is margin of error because clutch bellhousing and torque tube.
I'd have a guess at chain hoist (uk), chain winch (us).

Foggy, I really don't think the F7 16V is redblock weight, me and Dave can happily carry it around without struggling with manifolds/alternator still on. Redblocks you really need to think about.

Re: Fake - F7R Motorsport Daily

Posted: 01 Feb 2012 03:34 pm
by jtbo
Isn't F7 alloy block? Or was it still cast iron like redblock?

I have misplaced my user's manual, there was weights of each model and many other stuff. I think that it might be in a room that I sealed off for winter time, I open that when heating season ends so might find weights then.

I remember that 360GL was 1075kg, 1.7 might have been something like 1045kg ? 1.4 was surely under a 1000kg, early models were really light compared to later ones, but can't remember exact figures.

Re: Fake - F7R Motorsport Daily

Posted: 01 Feb 2012 09:29 pm
by jon-ovlov
Just seeing you guys talking about weight, mine with the F7R weighed in at 890KG when I took some stuff to the scrappy. (don't know how accurate the weighing scales at the scrappy are mind you). But now with the rear seats and stuff removed I reckon it'll be around 870ish kg.

But like Chris said, me and a mate can easily shift the F7R around with everything still attached. Would be good to know how much the engine weighs though.

Re: Fake - F7R Motorsport Daily

Posted: 02 Feb 2012 12:51 am
by Hell Driver
Every big drive on weigh bridge I've come across is accurate to the nearest 20kg, but a smaller scrapyard bridge might be to 10kg, there's a smaller bridge at my local scrapyard as well as a full size but can't remember if its 10 or 20kg.

Re: Fake - F7R Motorsport Daily

Posted: 18 Feb 2012 06:50 pm
by Chris_C
8k VDO rev counter part 1 completed.

That is all.

Re: Fake - F7R Motorsport Daily

Posted: 18 Feb 2012 07:18 pm
by macplaxton
VDO? :?

Re: Fake - F7R Motorsport Daily

Posted: 19 Feb 2012 06:43 am
by volvosneverdie
You reshelled with Foggys?

Re: Fake - F7R Motorsport Daily

Posted: 19 Feb 2012 01:56 pm
by Chris_C
Nope, just bored of projects that soley exist to keep the car running.

I wanted a fun project.

Interesting side note, first rev counter out the stack under read by 600rpm. That worries me with what I do on the F7R...