My 200mph budget build

Status
Not open for further replies.
Associate
OP
Joined
29 Dec 2005
Posts
1,194
its going reasonably well, there should hopefully be an update in the morning if some parts arrive, if not ill be updating it on monday.

start saving my friend, they are worth it, but if you ever go buy one check the compression of the engine and also if its on the original engine.

once they reach a certain age the water seals go brittle and break(normally around 70k miles)

to be fair its not really how many miles its done, its how many times its been brought up to temperature.

If the car was daily driver that had to be driven 150miles in one go every day then 70k isnt nothing to be worried about, but if the car only gets driven say 5miles a day then thats a lot of heat circuits the rubber water seals has been through to which cause brittleness and then you need to rebuild.

If you get to the point where you have £3k give me a shout and ill help you look for the right one.

£10k for 200mph/700bhp.....not that bad when you think about it, theres no way to go faster for less!! :)
 
Soldato
Joined
13 Jul 2004
Posts
20,081
Location
Stanley Hotel, Colorado
r888s are great BUT they wont help your top speed at all mate you get a lot more rolling friction from sticky tyres than normal tyres



Rolling resistance isnt the problem compared to air resistance which is exponential and at these speeds it'll be like pushing a brick wall or another car in front, sideways :p http://www.youtube.com/watch?v=jF6EiLn8bto


Whats the cd factor, frontal area, air resistance estimated for 200mph ?


Good idea on not doing standing starts but ultimately its this bit of maths which will determine success or not I think

http://en.wikipedia.org/wiki/Drag_(physics)#Drag_at_high_velocity

I think thats the right equation & fluid density is a constant . Im sure this must have been mentioned by someone or can be quite easily worked out now.
I'd be interested to know just how much power will be required anyhow, I didnt spot it on the thread


Will your car have a roll cage for this and might be best to wear proper head support also http://en.wikipedia.org/wiki/HANS_device




In case no one else mentions it, polish your car well before you do your attempt.
If you intend to go as fast as an aircraft then surface drag will count towards the power required just a bit I think, worth doing considering it only costs elbow grease :)
And take off the number plates also I think or tape up the front even, not sure, one for the boffins that but it does matter, probably more then tyre rolling resistances




image005269174101std318.png


http://www.kilowatt-house.com/kilowatt-car
 
Last edited:
Associate
OP
Joined
29 Dec 2005
Posts
1,194
Rolling resistance isnt the problem compared to air resistance which is exponential and at these speeds it'll be like pushing a brick wall or another car in front, sideways :p http://www.youtube.com/watch?v=jF6EiLn8bto


Whats the cd factor, frontal area, air resistance estimated for 200mph ?


Good idea on not doing standing starts but ultimately its this bit of maths which will determine success or not I think

http://en.wikipedia.org/wiki/Drag_(physics)#Drag_at_high_velocity

I think thats the right equation & fluid density is a constant . Im sure this must have been mentioned by someone or can be quite easily worked out now.
I'd be interested to know just how much power will be required anyhow, I didnt spot it on the thread


Will your car have a roll cage for this and might be best to wear proper head support also http://en.wikipedia.org/wiki/HANS_device




In case no one else mentions it, polish your car well before you do your attempt.
If you intend to go as fast as an aircraft then surface drag will count towards the power required just a bit I think, worth doing considering it only costs elbow grease :)
And take off the number plates also I think or tape up the front even, not sure, one for the boffins that but it does matter, probably more then tyre rolling resistances




image005269174101std318.png


http://www.kilowatt-house.com/kilowatt-car


Exactly, to do 200mph within the distance of the airfield will take about 650bhp to achieve, my aim for the car is 700bhp to give me a bit of lee-way so that i dont have to do loads of runs to hit my target figure.

A 4 door new shape toyota corolla that was running a 650bhp engine with 4x4, now that car will have a much larger frontal area that mine and have larger drivetrain losses so will be putting down less power to the wheels, hence why i think i should be pretty comfortable with my power figures

The drag co-efficient of my car is 0.31 and the total front area is 1.79m2 if that helps with your figures, but i dont know what the air resistance will be so if anyone wants to chip in with that im happy to hear it

The only thing with that is that this is a bit more of a sprint race because of the short distance, if i had unlimited distance then i think it could be achieve with around 550bhp(assuming gearing is spot on etc) but thats just a guess.

The car wont have a rollcage, i may wear a helmet if someone will lend me one, but due to the large amount of land i have to play with unless someone shoots me with a missle launcher(dons tin foil hat) then i should be fine.

In terms of extra 'slippyness' i do have some proven data from america to help with that.

Removing the door mirrors gained 2mph at 190mph+ Taping up all the seams agained another 1mph so they will be done on the day, also a good polish will be put on as even if it gains me 0.1mph then thats worth it.

I remember reading along time ago that the difference between a clean polished mini(old style) and a dirty one was 2mph topend.....cant remember where i read that and might be complete rubbish though.
 
Associate
Joined
8 Jan 2007
Posts
1,975
Location
Barcelona
Just a thought, but wouldnt it be easier for you to buy a second hand front bumper and fiber glass over all the cooling ducts/smooth the edges off, then just use the standard intercooler covered in ice for the duration of the run? The charge temps will easily be cool enough if you arent doing back to back runs and it will make a big difference to your aerodynamics.
 
Associate
OP
Joined
29 Dec 2005
Posts
1,194
Little update, my quickshift arrived today, yes it wont have any benefits for top speed but just fancied one.

p20031013390001.jpg
p20031013430001.jpg
p20031013390001.jpg


simple design

p20031013430001.jpg


Its actually a B&M replica but its actually better than the real thing because the real ones are made out of aluminum, yes thats great for weight but there is a flaw in that the material isnt strong enough in my opinion, infact i snapped one in half at the drag strip so i know it isnt.

The replicas are made all steel so while they are heavier, they are also stronger.

ok time to install!!

stock
p20031014130001.jpg


remove gearknob, just unscrews
p20031014140001.jpg


remove covering
p20031014150001.jpg


remove rubber sound deadening/wind resistance thingy
p20031014270001.jpg


remove stick and bolts hold in, hit with hammer to break seal, becareful of gear oil going everywhere
p20031014410001.jpg


pull plastic boot off original and fit to new quick shift
p20031014410002.jpg


bolt new quickshift down with supplied washers and bolts
p20031014520001.jpg
p20031014520001.jpg


replace rubber covers, replace big plastic cover, reconnect switches, good as new:D:D
p20031015120001.jpg


Well first impressions, my god!! Its so short and feels like im using a completely different box, gonna take some practice on the gear changes as it is very notchy, reminds me of a HKS dog box in a GTR that i once drove, it should settle down as i break it in but feels pretty made at the moment!
p20031013430001.jpg
 
Soldato
Joined
19 Oct 2002
Posts
16,896
Location
Shakespeare’s County
In case no one else mentions it, polish your car well before you do your attempt.
If you intend to go as fast as an aircraft then surface drag will count towards the power required just a bit I think, worth doing considering it only costs elbow grease :)

In all honesty that would make next to no difference. Its not a solar racer where you can't even put stickers on them incase you breakup the laminar airflow over it.

The airflow over the car will be turblent with a significant boundary layer between the moving air and paint surface therefore the actual finish of the paint wont really make a difference.
 
Associate
OP
Joined
29 Dec 2005
Posts
1,194
Just a thought, but wouldnt it be easier for you to buy a second hand front bumper and fiber glass over all the cooling ducts/smooth the edges off, then just use the standard intercooler covered in ice for the duration of the run? The charge temps will easily be cool enough if you arent doing back to back runs and it will make a big difference to your aerodynamics.

Not a chance mate, putting 100lbs of air through a standard cooler wont be cool enough by a long way, being covered in ice wont make a difference enough to off set that kind of heat.

Also it will be a size restriction in the system, its like putting a resister in the circuit.

the option you may be thinking of is the bonnieville rx7 from racing beat that did the same thing with the front end by making it all one piece.

The difference is that they ran a compund charged triple rotor engine that made 900bhp, this was compound charged and also running a chargecooler setup so it could afford to have its front end closed off.

Rotarys run very hot so its not advisable to cover the cooling ducts for the oil coolers that the rotary engine heavierly relys upon(more than a piston engine) then staying at full throttle for 30secs+

In all honesty that would make next to no difference. Its not a solar racer where you can't even put stickers on them incase you breakup the laminar airflow over it.

The airflow over the car will be turblent with a significant boundary layer between the moving air and paint surface therefore the actual finish of the paint wont really make a difference.

Your probably right to be fair, but since the car is going to be in the magazine ill give it a wash and a polish anyway so cant really hurt it
 
Associate
OP
Joined
29 Dec 2005
Posts
1,194
that may be useful, i have a co2 extinguisher in the house but depends whether im gonna use it, i dont think its really needed, maybe blast the intercooler for a few seconds before the run, it may help a tiny bit with accelaration before 120mph but doubt it will help a lot after

Ill be using a pre turbo water injection system which will spray pure water into the turbocharger to cool the air coming out of it before it enters the intercooler, that should help keep my temperatures where i want it.

also because it will be about 800cc/min of water, a lot of that water will pass through the intercooler and enter the engine to act to resist det.

Im not expecting the intercooler to do all the work even if it is massive

So overall it should be pretty effiecient
 
Soldato
Joined
19 Oct 2002
Posts
9,964
Location
Jupiter
Just read the whole thread, very impressive :)

I saw Stormster ID'd you as having the white R5, presumably the one with the HUGE intercooler on the front? Used to chat to you years back at Festival Park, i had a white R5 Turbo replica :)
 
Associate
OP
Joined
29 Dec 2005
Posts
1,194
god yeh thats going back a bit, yep, loved that massive cooler, 35psi of boost and 30c inlet temps was nice, i actually think i remember you from back then, though it is a little hazy.

What you driving around in now?
 
Associate
OP
Joined
29 Dec 2005
Posts
1,194
its a place called bruntingthorpe, its an old RAF base, basically you get to use the 2mile runway to do whatever you like.

http://www.bruntingthorpe.com/index.html

because normally you go if your car is gonna appear in a magazine they pay for it, because of safety team there should the worse go wrong i think they charge £50 an hour to hire the place out.

Sounds a lot but only real place you can legally go for a top speed around here.

You dont have to have a mag to let you go, if you get a load of people you could hire it out for the day.

Say 7hrs is £450, split that between 10 of you and its worth it
 
Status
Not open for further replies.
Back
Top Bottom