My S1 Elige S Build...hopefully 480bhp/ton.....assembly mode

General Owners Cars
1

Well since im getting close to do more of the major parts of the car I decided its time to put a build thread up on here, hopefully to share my ideas and have people give me tips who know more about exige chassis and rover k series than ill ever know.

So to give you an idea of what im doing and my eventual aims.

Build my ultimate track day and then time attack car.

I want to have the car finished by the end of the year, with the hope to enter time attack in the club class next year.

The vehicle is being done on a budget and everything will be done by myself so I can control costs(learnt my lesson the hard way)

Ok here is the spec, first list is what is done already and second list is what im due to do…at any point please pitch in with ideas and comments.


Bought s1 111s
Turbotecnics supercharger conversion inc pistons/rods(full kit weighs 18kg)
Piper 270 cam kit(vvc delete kit)
Emerald m3kd
remote thermostat
ITG cone filter
janspeed 4-2-1 manifold, sports cat and exhaust
Large hofmans oil cooler kit in drivers side rear arch
Nitron NTR 1 ways Randy spec 450/650 with eibach helpers
pilbeam adjustable ARB
eliseparts ali bell discs
braided lines all around
removal of stereo, speakers and wires
lightweight golf cart battery(5kg)
battery cut off
Harness bar and 3" Luke harnesses
eliseparts quickshift
eliseparts 50mm hub adapter, ebay snap off extender and 280mm wheel
padding removed from stock drivers seat and rotated to lower head height(im 6ft3 hence this and the wheel)
stock 111s wheels
75mm extended diffuser and 1mm ali undertray with no naca ducts
Carbon interior panels and doorcards.
92/102 ride height(did this by mistake, took 15mm off the coilovers and lowered it 23mm for some reason)

I think thats about it, car currently weighs around 730kg with an empty tank, my aim is 680kg which I think is achievable.

Stuff to do.

Equinox Fibreglass Products full Exige body including roof made to my specifications with a diolen/fibreglass mix with black gelcoat(is being made at the moment and due for me to pick up next weekend, expecting a 20kg+ weight saving)
Removal of rear glass for a bonded in carbon panel(already have it in the garage)
Full splitter with 4inch extension all around, mounted to chassis, crash structure and tow eye.
large rear wing the width of the rear clam(my aim is a total of 300kg+ of downforce at 100mph, will adjust the rear wing to balance the front splitter.
Ethos wheels from Sector 111 in 16x7 and 17x9 with 205 front and 245 rear(may go to 255 if theres room but dont think ill have enough power for a while to justify the extra rotational weight)
Innovate wideband connected to my emerald
Piper 285 cams
DVA big port head and valves
increase size of restrictive pipe between throttle body and supercharger
modified exhaust system to have a straight pipe from manifold to out of clam.
swap TT top inlet manifold for a stock VVC one, replace injectors with 4 x bosch green ones
Then im up in the air on whether to put a proalloy chargercooler(keep my pump, lines and rad from the TT Kit) or an intercooler with air provided by roof and extra ducts(would be lighter and less to go wrong)
Phoenix motorsport toelink kit, brace and then lighten my hubs(says can save 1kg per hub!)
My mate works for a carbon fibre manufacture so is making me a set of seats, expecting to save 10kg+ for this.
going to try a 300mm wheel as I cant see any of the dials properly

As mentioned my aim is not big power(around 250bhp) but to gain by colin chapmans philosophy of being as light as possible.

Here are a few pictures, dont really have many up to yet as ive prefered to work on it than taking pics.

What it looked like when I got it

seat adjusted, snap off kit and extender added

picture from recent pistonheads meet

front clam setup

roof, but ill also be modifying it for more air if I go for an intercooler, also the roof will be removable without havign to take the clam off

diffuser added, I think from what people said when the exige body on its going to not stick out anymore, I might make an even longer one to help with downforce in the future

engine, still need to sort out a catch tank instead of running a simple breather.

new ITG filter fitted and intake tube, had the inlet the same as the throttle body(old stock setup had a small pipework

chargercooler pump died so had to take the clam off

clam put aside, no point putting it back on with my exige clam coming, after ive stripped it im going to weigh it(got 25kg fishing scales)

Thats it for the moment, will take pics when i go fetch my clams and will weigh each part so people have got some more information for anyone else after a set.

Any questions or comments on my ideas please feel free to let me know

Lee

2

:sunglasses: Excellent another build thread, good luck I will follow closely.

3

Yeah, looking good!!! Does the ace you got the body from have a website? I don’t think I have heard of those guys before.

4

thanks, ive followed yours all the way through, your engine looks brill, cant wait till to see what it goes like on track, im hoping next time all the guys are at oulton park/donnington someone will let me know and ill pop up to see, I wont be able to play with the audi guys, but im hoping to be able to play with the s2 boys

Here you go, discovered him from ebay actually, then maidstone told me he does all there exige bodies for there race cars, I did want to go with TTexige but he lost his moulds and only has the the wide body ones he made from you, I just never thought i would have enough power to justify them.

http://www.equinoxproducts.co.uk/shop/viewcategory.php?groupid=16

he can make them any thickness you require, his standard is 1200g/m which is the same weight as stock clams, mine will be 700g/m with the outer layer being diolen to give me impact resistant against stone chips, he will cut you a good deal if you buy a full kit from him, Wayne mentioned it was a good price and said he would like to have a look around my car when its done as hes thinking of getting a new body, plus a few people on midland forums have mentioned they will want a front exige clam when they get to look at mine

I was hoping to get your input on my build actually as you seem to have pretty much done everything with s1 exiges, any comments on where I can improve and if im wasting my money anywhere.

Do you have any info on your current setup as I have only seen the odd picture but not much info

5

:wink: Sounds good

6

Well got a new chargecooler water pump fitted today, had to wait till my mate came over with a soldering iron so havent had the chance to see what sort of inlet temps im getting as it was getting dark and having no headlights might be a issue :laughing:

But good news was while it was light i nipped down and weighed it, came out at 709kg without clam and 5kg of fuel, when I got home I weighed the clam(which had lights in) and that was 17.7kg so total weight of 721.7kg with an empty tank, taking away the 18kg of supercharger and 5kg for oil cooler to compare to a standard car puts me down to 698kg which isnt bad.

so doing these mods should put me at

proalloy tank -4kg
carbon seats - 10kg
replace rear glass with carbon -1kg
smaller straight exhaust with sport cat removal-5kg
phoenix motorsport to lighten my hubs -4kg
removal of chargecooler for intercooler -5kg
boot replaced with exige one -2kg
front clam -5kg
rear clam -15kg

Total: 670kg, again interesting that if it wasnt supercharged or had the big oil cooler then it would be under 650kg.

After that it would be lightened flywheel, but thats when I get a slippy clutch, not bothered about taking the box out with good reason.

Dont think theres anything else I can remove without making it a bit to hardcore to enjoy driving on the road, so i dont want to go to strip the doors.


One question I wanted to ask was, when I come to fit my front clam, is there any recommendations on how to fit it so thats it much faster to remove as it takes a while to do it on your own, my mate mentioned dzus fasteners but I cant see how you would get them to work on the body, he did say use some carbon angle, bolt that into the body(the 2 at the bottom rear of the front clam) then fit dzus fasteners to that, that was removing both rear sides takes a couple of seconds, but then theres all the other bolts I need to look at.

has anyone modified the s1 elise/exige front or rear clams to make them quick realise?

7

Well a quick run tonight to test inlet temps. Confirmed that im running 10psi of boost, with a 5c ambient temps with a run from 2nd all the way up to top end of 4th and it peaked at 33c, so a 28c temperature differential, this is fine during the cold months but during the summer when temps get up to 20c, runnign 48c in my opinion is a little to high.

So im not sure if a larger chargecooler barrel will help or not, I would have thought it would allow more transfer of heat into the cooling system, so closer air to water temps, but would need to put a temp probe in the water to see the difference.

Also looked again at seans intercooler testing and even with 2 x 4" pipes blowing into the intercooler hes 25c above ambient, since I wont be able to provide that much air on an s1 it looks like an intercooler is out as all I would end up doing during the summer is pulling timing out as temps rise costing me power

I would like to get the intake temps to be 15c above ambient so im either going to buy a chargecooler off proalloy or get one of the barrel types from the US

8

That’s a shame, surely you can get the extra air from somewhere?

9

I dont think so, one thing the mr2 turbo boys do is put the intercooler in the boot and have a big duct from underneath bring the air through, that would work in theory but you have an exhaust in the way and I would rather that air be channelled to the diffuser to help with downforce than cooling.

Bit of good news and bad news yesterday, took my car to the local dyno yesterday so see what we are starting with, turns out its running lean under boost as the secondary injectors arnt working, like 16afr from 5000rpm onwards!!

Still managed to do 203bhp and 186ftlb before running out of fuel which is a good sign and shows theres more in the supercharger once I stick the rover tomcat injectors in, I think it should at least do me for this year while im still developing the car, also the 28c difference in inlet temps was still true, on the last run of the day, it peaked at 42c in a 14c room.

What ive decided to do is instead of buying a bigger supercharger, making brackets and general messing around is not going to be most cost effective or the best for power, so Ive decided to go turbo, using the rover 75 turbo manifold, t2871, 200sx downpipe and then run a bigger barrel chargecooler sitting above the head, this should get me into the low 300s without big expense as I would have thought my janspeed manifold, tt supercharger and chargecooler must be a worth a little bit.

Also managed to strip my front clam completely and it weighs 11kg, the lights, hinge and electric 2.5kg and the bonnet weighs 3.3kg, so im hoping the front clam comes to me at 6kg for this to work out.

Finding accurate weights of clams does seem to not be easy to find so though I would put this on here if anyone needs that info in the future

10

mini update, weighed the GRP 111S rear boot, with latch but without the metal spacer plates - 4.5kg

Also removed most of the bolts out of the rear clam so that will be coming of at the weekend so i can weigh that.

Has anyone run just standard brake calipers on a race car before? Im hoping the drop in weight will offset the extra power im producing so overall they wont be to bad.

I think I read running pagid rs14 is the right compound on stock calipers, is that correct?

11

mini-update

Removed the rear clam, took drivers side wheelarch liner after this picture

19row oil cooler, removed fan and over from it as it wasnt working and dont need it, you can also see how small the chargercooler is, definite need for improvement

you can see how small the intake pipe between the supercharger and throttlebody is, that needs to be enlarged

this needs sorting out, theres no way I need this much wiring and pipework, have started to strip the wiring loom down and remove the excess and simplify the coolant system, also unbolted the rear hinge for the engine cover as wont need that.

There has to be a simplier way of getting the gases out than this, lots of pipework and weight, probably take it off and use it as a template for a straight none cat setup

This will also mean I can make a new exhaust that can be bolted to the carbon panel that will bolt between the longrons where they meet the subframe, I also have another carbon panel to replace the rear window.

Also had an email from the clam maker, the front clam weighs 7kg, so saving me 4kg over the stock elise one, Im hoping the rear is where I make most of the weight saving.

One thing I did think of was removing the small oil cooler that sits in the front crash structure and bolt the larger 19row in there, I would be suprised if the engine needs a 19row and a 10row to keep the oil temps in check, that would mean I could use both side intakes with 4" inlets took feed an intercooler as per seans s2 exige which would mean I can dump the chargecooler and rad(which would allow more air to the engine rad and save weight) then the air filter vertically upwards and have the roof scoop feed it.

My only big concern is that the longer run of pipework will cause a pressure loss which will cost me power over the short run on the current setup, its not like I can just turn the boost up as the supercharger is already at its limits, but then if I do turbocharge it in the future then that wont be an issue at all.

12

Lots of potential and carbon… You’ll be needing some gold as well :smiley:

13

My mate uses the runners gold wrap that you have run a marathon, can get it for pennys, and use glue to stick it to parts, seems to work almost aswell as the self adhesive gold you can buy, I would love to use it but I would need to take the engine out to do it properly and for the moment I would rather leave it in.

Bit of an update, copied from SELOC.

been working on the wiring to take what we dont need out of it(old vvc stuff) and also tidy it up…what a complete mess it is, whoever was at it before clearly didnt have a clue what they were doing, im just starting to rewrap it now its all sorted.

Next job was to make something to hold my exhaust and provide me somewhere to put a bag of tools, jack and other bits and bobs ill need to take with me on track days.

So i cut to shape a foam core carbon panel, bolted it to the car,

then drilled the holes for the exhaust to bolt to, its lightweight and stiff so should do the job

Here you can see most of the wiring is now wrapped, just this last bit, also had a think about where im doing to put my emerald and that black box at the bottom of the picture.

i dont want it getting wet or dirty from grime so we raided the cupboards and found a lockable plastic tupawhere box that will just about fit both in, so Ill be fitting that tomorrow, also means now we can drive it about without the rear clam on to do some final checks before bolting the new body on.

Well yesterday i went and fetched my new exige bodywork, left at 8am in the morning, got home at 7pm, so along time on the road, met Dave at Equinox products and I have to say, really nice chap and would happily recommend him.
After getting home I finished the wiring off and managed to get it running making sure all the sensors work as they should

so we can officially say its moving from elise to elige as such.


Didnt really know what I was letting myself in for as ive never done bodywork before and was hoping it would be a case of drilling holes and bolting on, looks like im in for a bit more work than that!

Gave the panels a quick wash off just to see what we are starting with, my advice would be to paint these, but if its a racecar then it will be fine as it is, I think ill do a couple of seasons of time attack then maybe get it painted to match the doors.

Front clam(very light)

Rear clam(pretty heavy, but still 10kg lighter than stock)

what we are starting with, funny looks turning it around in my street, plus a few of the local kids thought it was a big gocart

tried the roof on, seems to drop in nicely and gives me an impression on what needs to be done to fit it.

You can see how much my seat it adjusted to keep me as low as possible, im 6ft3, I put my helmet on, doesnt touch the rollbar and I have 1inch clearance between the helmet and my the roof, would like more so hopefully the carbon seats will get my even lower.

Here you can see the gap between the window and the roof, need to sort out some window seals, I have seen you can use s2 exige ones on a s1 so might try that.

Dave had not fully trimmed the front clam so that we can adjust it to suit it better, so we made a start, theres still a bit more that needs doing to it, but at least now we could bolt it on roughly

Starting to look a bit like an exige now

Plenty more work to do, hopefully will able to get the front clam including chin and splitter completed by the end of the week, then next week make a start on the rear.

Was thinking once Ive got it all bolted on take it up to my mate who runs a body shop and get him to run over it for a couple of hours and get all the panels aligned correctly as they wont be perfect doing them myself.

14

Also mini-update tonight, trial fitted the arch extensions, only thing I need to work out is how to attach the bottom part of it, not sure if they get pop rivetted or bonded on factory exiges

you can see how wide the front arches are compared to the elise ones

Put the front splitter up to see what the fitment is like, seems fine, so tomorrow i will hopefully ill drill and bolt them together tomorrow

Well had a good few hours on the car today.

My rubber rivnuts turned up today, they are brilliant, £2 for 10 and do the job perfectly.

they take m5 bolts, you just need to make a 9.5mm hole, push it in with your fingers and thats it.

So i used one to repair the one in my front sill that was knackered and then put them on my sill extensions

When you tighten up the bolt it will push the metal insert upwards which pushes the rubber sider making a seal.

I then drilled out the lower bit of the clam and also the chin lip, just waiting for my stainless bolts to arrive this week to bolt them together

Once that was done I designed my splitter out of a 9mm ply with a 4inch extension, decided where to mount it, measured everything up and will be cutting it out on monday.

This is what ive come up with, the grey represents the chin spoiler, orange shows the splitter

I did try to trial fit the rear clam but after 30mins I realised i need 2 people to be able to fit it so thats a job for when I can rope a friend in.


Also went to see olly at phoenix motorsport, what an awesome bloke, told him what im planning on doing and also asked for his advice, hes come up with some amazing ideas of taking weight out of it that I had never even thought of, also ways of running lower without having to spend £2000 on uprights.

With all this, my plan was 680kg, but looks like we will actually get closer to 665kg!

I got the piece of 9mm home tonight, spoke to my mate and hes said he might make a carbon foam core version of it once we have trialled the ply version.

You can see how far it will stick out from the clam, but my god its heavy so I cant imagine ill be able to live with ply for very long.

The brackets you have coming down on the rx7 are similar to the setup the lotus has from factory at the bottom of the crash structure, the issue will be the frontal section and how the ends will be kept from bending, that will be tied into the crash structure again but with tie bars.

Also contacted the supplier of the backbox im getting, hes had it on the scales at 4.13kg, now adding the small bit of flexy where it meets the manifold and a small elbow out of the box pointing down should get that up to just under 5kg, so thats a 8.7kg saving and hopefully a extra horsepower or two from lack of 3 bends the old system had.

this is the old janspeed setup with a represent over the top showing the new setup.

The only bend will be at the end pointing down at the track to help with driveby tests, ill put it on with a slip fit so I can adjust it away from the sensors depending on which track it will be.

The box should be arriving by friday and ill get it welded over the weekend

Well mini update again,

From watching and looking at my datalogs from emerald you could see that the inlet temp sensor was struggling a little with heatsoak from head.

So I decided to remove it from the lower inlet manifold and put it in the upper inlet manifold, so out came my drill and M10 Tap.

I used an old IAT sensor and ground it down top and bottom to remove all the sensor part, making sure that nothing protruded into the inlet stream so that each runner was getting the same amount of air.

This way ill know a more accurate idea of what the temperature is coming out of the chargecooler at all times.


Also my new backbox turned up, looks nice and I think this will be one of the most cost effective ways of reducing weight, whether its quiet enough remains to be seen.

You can see thats pretty free flowing!

On thing I did notice with the janspeed system is the internal diameter of the pipe work is smaller than 2.25" so hopefully it might realise a pony or 2

Dropping it all of with my friend in the morning, hopefully he will all get it welded up over the week

pics of carbon brackets, went from 400g to 51g

We are using one direction carbon box section, strong as steel yet doesnt weigh anything, for example, 2m long 1"x1" box section weighs 300g!

Need to replace as many steel things I can with either ali or carbon, hopefully olly will be able to throw a few ideas at me.

Ok next I moved onto the rear of the vehicle, looks like more trimming to do.

At least I can see the light at the end of the tunnel now, plus its a nice feeling looking at it, makes me think its going to be worth the effort.

One thing I realised as once its fitted I really need to take it to the paint shop and have a proper body shop go over it from top to bottom and tidy everything up, luckily Ive got a friend who runs one and ive already ran it past him.

So ive placed everything where I want it, need to start at the front of the clam and work my way back.

One thing I noticed is how far the rear wheels are in stuck in the arches, they look a bit a bit lost!




So also made a post on here about what im going to do for tyres, ive done some measurements and these will be the ones ill be running


Rota GRID V

15x7 ET20 with 25mm hub spacers on 225/50/15 this will sit out 38mm than my stock wheels(ive checked and have the room
16x8 ET20 with 25mm hub spacers on 245/45/16 this will sit out 21mm than my stock wheels

Should look something like this when its finished

mini update, tomorrow we will have put the final couple of pieces on to finish mounting the rear clam, least then on monday I can drop it off at my mates garage to do my new exhaust.

this is how we are going to mount it, the light grey is the longeron and the bit sticking out that we are bolting it to is the fog light housing.

we are using some spare carbon angle that will be bolted in 2 places to the longerons and then the end of that will be bolted onto a 90* which is bonded to another 90* piece which is bolted to the clam, it seems like the simplist and lightest way to do it.

Next I tackled the problem of the rear wheelarch not bolting to the sill, the exige workshop manual doesnt seem to show that there is a bracket between them so im guessing the exige sill is wider than the elise.

Because its quite a struggle to do this with the rear wheels on(needed to so I could jack up the rear of the clam) I decided to make them out of 1mm ali, since they are very light ill try it out to see if theres any flex, good thing is now i have a template to make them out of carbon angle later ive saved ready.




Ill hopefully be finishing off cutting the engine cover up this week aswell so that the front section follows the contors of the roof, ive done the passenger side already, just need to do the drivers, you can see on this picture how much it currently sticks up




Again since it was sunny today I took a picture to give me a little inspiration that there is light at the end of the tunnel

Currently sitting at 92mm/110mm ride height, will be interesting to see if I can get it off my drive tomorrow!!

Another mini update

We have finished bolting the rear clam on so at least now tomorrow I can take it to have the exhaust made.

we used carbon angle that is bonded and bolted together, the good thing about this, once the bolt holes are lined up we know the rear is in the correct position, I might change over to quick release fittings in the future but for the moment it does a pretty good job, its only 2 bolts which takes a minute


Here it is made, didnt take long but it sure does blunt drill bits making the holes, being 3mm thick it will take a massive chunk of weight

Holds the entire back end rigid in place and only says 200g for the pair!

Here you can see how its bolted, ive put some weight onto it and seems fine, cant put to much weight on it as the clam is only thin and you risk spider cracks.

You can also see the diolen we have used to give the clams more flexability and impact resistance, this means we can go lighter and less chance of cracking.
The only bit he didnt do in diolen was the rear where the lights etc go, but alot of this will be cut out eventually so wont matter to much,


Looks pretty evil from the front, actually like how it looks without lights/indicators but dont fancy getting a daytime MOT for it incase i get caught coming back from a track day and it goes dark, if it was a race car I would put come blacked out headlight covers and be done with it.

Running so low the most challenging thing has been to work out how to get it off my drive!! but worked that out this afternoon, involved many different pieces of wood, still the lower the vehicle the better aslong as i can counter act the bump steer and wishbone angles.

marking out where the exhaust will go, thank god I went for the shorter one with the bigger diameter, I will be cutting all the exhaust section of the clam away to save weight but even so i dont think i would have much space for much more

Cant get it any closer else the box hits the subframe and im trying to avoid tight bends for better flow, the old system had the equivalent of 6 90* bends

Put roughly where we want it, i will then use a slip on 90* bend which ill be able to turn away from the direction of the sound recorders on trackdays

15

coming along well :smiley:

16

That was a really great read, well done, so far so good. Keep it up :thumbup:

17

Well im trying to keep my car 150kg lighter than a porky s2, but your making it harder for me by making your car so light, have you any idea what your is down to now?

Ill be popping onto the weighbridge on the way home which I think will put me at about 710kg, which i have already calculated 37kg of weight to come out of this through wheels/hubs/brakes/seats/fuel tank/carbon roof/engine mount/knee pads

I think after that im running out of ideas as I dont want to compromise the car that its uncomfy on long journeys, so I wont be gutting the doors/running perspex windows/removing heater matrix(if i did then it would get me down to about 650kg

One last thing is what Olly suggested is we go from front to rear and replace every bolt and washer for aluminum ones where its not carrying the weight of the car, thinks it will save around 3kg, but then we need to think about how much it will cost.

18

Fascinating. A good read. Well done.

19

I have my lardy SC S2 down to about 890kg with 1/2 a tank of fuel, I reckon Mr fox will be best part of 100kg lighter than me given the diet his car has been on.
My S1 sport190 was very light at 670kg and I really do miss how nimble it was as there was no weight to chuck around

20

For those extra 3Kilos , you’ll find senna is your friend.