DW's (new?) Sierra 3dr YB race car

[Graham]

Re: DW's (new?) Sierra N/A PINTO race car

Go for the alloy block.
Would be a nice touch in getting the car lighter and beneficial for the weight distribution.
Also you could choose a higher block if needed.
Not so budget friendly tough. But hey you only live once....

that would certainly go a long way to keeping the weight down to n/a pinto weight but its a hell of a cost,
dave might have to sell the car just to pay for one!!!!!!!!!!!

[markb]

Re: DW's (new?) Sierra N/A PINTO race car

Not too worried at the minute Mark as the system is 3" all the way through and should be plenty big enough for the power we need. The rear box will ultimately get replaced with a re-packable silencer anyway but at least we will already have all of the bends etc in place.
As for noise my more revvy NA engine on TBs ended up with a single box and was ok, so with lower revs and a turbo I should be fine.

Repackable silencer sounds like a good plan mate.
Just hope it's quiet enough! Then again, having heard some of the cars in the series I guess it should be.

[david_white]

Re: DW's (new?) Sierra N/A PINTO race car

Should be ok for noise, certainly isn't a concern yet. We'll find out when its running, prior to racing it.

As for the alloy block I'm not convinced on many levels. It may not be legal in some series, is it strong enough in the long run? and without walking the 30 miles to work and living on rice where would the extra £5k come from for the build? I think I'd be more inclined to go that route if I was buildng a no expense spared N/A lump, but for that money I could get 550bhp with a T4 and neither of those options suit what I have in mind.
I want a strong, reliable engine that makes the car both competitive in its class and fun to drive much in the way the pinto was with not worrying about it grenading itself all the time.

[Roadsport]

Re: DW's (new?) Sierra N/A PINTO race car

All those things said about the alloy block are pretty much true. Would make for a one different YB though.

[robt100]

Re: DW's (new?) Sierra N/A PINTO race car

On the weight side of things, I guess its a balance on costs, is it going to be cheaper to replace materials etc to make it lighter with lower power and be stuck with the balance. Or to maybe add a few bhp and create some moveable ballast to help setup the balance of the car? Depending on the current weight adding balast might not make much of a diffrence, I guess its down to what you can afford on the engine/tyres side of things.

[Graham]

Re: DW's (new?) Sierra N/A PINTO race car

at the stage daves car is at it there are no big weight savings to be had, sure an alloy block would save weight but at huge cost, likewise a set of split rims would save weight but again its no cheap exercise, inn terms of spending money with the switch to turbo yb power it is probably better to spend ££ on the engine or a set of dog cogs for the gearbox, and save weight by removing surplace brackets and mounting stuff directly to the shell cutting down wiper linkages etc etc.

to go with the bigger restricter dave will probably have to bolt 50KGS of ballast in the car which is a lot, if you factor daves weight into the car in power to weight terms the bigger restricter size would have to give 10% more power to shift a car which is 10% heavier, 10% more weight though is a fair chunk less corner speed

[david_white]

Re: DW's (new?) Sierra N/A PINTO race car

My only fear is that we go for the smaller restrictor only to weigh the finished car and it comes in over 1050kg, which is a lot of weight to lose. Cutting off the brackets that I know of will be lucky to see a 5kg weight saving.
The advantages of the bigger restrictor that I can see are that the engine / turbo set up might be easier to spec and give decent power plus if 50kg have to be added they can be put where ever we want.

I need a set of scales for the car really

Good news is that SFS are gonna sort out some big wings and a new baffle kit for the sump along with a take off for the breather tank return pipe

[mervhill]

Re: DW's (new?) Sierra N/A PINTO race car

Good news is that SFS are gonna sort out some big wings and a new baffle kit for the sump along with a take off for the breather tank return pipe

Mine is with Doug now mate

[Graham]

Re: DW's (new?) Sierra N/A PINTO race car

im just glad i wont be deciding which restricter size we use

[robt100]

Re: DW's (new?) Sierra N/A PINTO race car

I can understand the more weight=slower corner idea, but a bit more power cant hurt surely and with the extra gubbins for the YB the balance of the car will shift slightly forward, that 50kg ballast might come in handy!
Also, just a point, #(costs again) cheaper to add 50kg and if it doesnt work to take it out and then start interchanging parts, rather than spend the money then need to put 80+ kg back into the car.

[Roadsport]

Re: DW's (new?) Sierra N/A PINTO race car

So basically 34mm restrictor means 100kg's lighter car. How much does the Sierra weight now? I'd be very tempted to go for the 100kg's lighter car!
Are all the allowed body panels fibreglass allready? Could you use 205 block instead of 200 block? Can you rebuild the rear subframe from lighter tubing.
Maybe locate 2nd hand split rims? Are there alloy wheel hubs available for the Sierra? Can you loose some weight from the brakes?

Surely we all know loosing weight is hard but I think the outcome would be better with the lighter car. If the only advatage from 50kg would be 36mm restrictor How much of a power difference can there be?

[Roadsport]

Re: DW's (new?) Sierra N/A PINTO race car

if you factor daves weight into the car in power to weight terms the bigger restricter size would have to give 10% more power to shift a car which is 10% heavier, 10% more weight though is a fair chunk less corner speed

I would say if the the power to weight ratios are the same the lighter concept would bring home the price.
But then again if the regulations do not allow major modification and changin body panel materials it would be a lot easier to wisely place the ballast where it is "needed".

[david_white]

Re: DW's (new?) Sierra N/A PINTO race car

Firstly thanks for the replies / thoughts chaps, it is a bit of a brain teaser.

Where we stand with the car weight wise is that when I first took it to brands last year it was bang on 1000kg, after which I tried to remove a few more bits of weight from brackets, cutting out the bumpers etc. Probably didn't go down a lot though.
I have a single skin fibreglass bonnet and tailgate, the windows are perpex, the doors are cut out a lot and the front bumper is carbon kevlar wih the rear being a origional with all of the internals cut out.
Whaletail is fibreglass and half the weight of the origional.
'Bolt on' weight loss would come from fibreglass front wings, doors and a perspex screen, but I doubt the doors and wings are that much lighter and I'm not a massive fan of plastic screens due to scratching etc. I guess if I fit a new screen every year it might be ok, and I could also lose a wiper and most of the mechanism but again the std setup works really nice and bad vision has never been an issue.

I have large brakes on the front but am not removing them for smaller ones at any cost, out braking is one of the cars strengths, besides they are billet anyway. The rears are std so work well but could be replaced with something a bit lighter but again at a cost. A nice small billet rear caliper would be nice though.

Don't know how much the wheels weigh compared to splits but they aren't the heaviest I've seen. Splits would be £1k+ too.

[david_white]

Re: DW's (new?) Sierra N/A PINTO race car

Where we stand with the car weight wise is that when I first took it to brands last year it was bang on 1000kg, after which I tried to remove a few more bits of weight from brackets, cutting out the bumpers etc. Probably didn't go down a lot though.

Obviously that 1000kg was with the pinto and type 9. A cossie lump, turbo, intercooler and T5 add weight but the dry sump set up has gone now which gets me a bit back..

[Roadsport]

Re: DW's (new?) Sierra N/A PINTO race car

I had the Compomotive ML wheels and lost 10kg when changed them to split ML's. What kind of front discs do you have?