SEAT Ibiza - rwd turbo
Discussion
I'd almost forgotten about this car!!! 
I remember it from SCN when I used to pop over during my dub days. You've certainly been building this for a long long time, and it will be epic when it's fully driveable.
Now, just Dogwood to finish his Hillclimb Polo now, yes Nick finish it FFS!!!
2014 is gonna be a mental year for some crazy car creations! 
I remember it from SCN when I used to pop over during my dub days. You've certainly been building this for a long long time, and it will be epic when it's fully driveable.Now, just Dogwood to finish his Hillclimb Polo now, yes Nick finish it FFS!!!
2014 is gonna be a mental year for some crazy car creations! Max_Torque said:
The main aim was to make one of these:
...This lead to a cheap, but time consuming process of doing my own Kevlar arches and panels!
Likewise, the F2 roll cage simply didn't work with my car, due to the positioning of things like the transmission tunnel, suspension turrets and engine orientation. As such, the cage in my car uses the genuine Safety Devices main cage "hoops" from the F2 cage, but all other tubes are custom to suit...
...This meant a simple Strut and wishbone style system at each corner was a good compromise, giving decent control of wheel paths without excessive complexity. It did mean that a high dynamic roll stiffness would be required however, as with struts, bodyroll is very nearly 1:1 with tyre camber change. As such, tuning the initial camber setting and the front rear ARB stiffness would be critical. At the time, there were a lot of people chopping in GrpA cars for the first of the hand-me-down WRC cars,
Amazing stuff. Few questions if I may......This lead to a cheap, but time consuming process of doing my own Kevlar arches and panels!
Likewise, the F2 roll cage simply didn't work with my car, due to the positioning of things like the transmission tunnel, suspension turrets and engine orientation. As such, the cage in my car uses the genuine Safety Devices main cage "hoops" from the F2 cage, but all other tubes are custom to suit...
...This meant a simple Strut and wishbone style system at each corner was a good compromise, giving decent control of wheel paths without excessive complexity. It did mean that a high dynamic roll stiffness would be required however, as with struts, bodyroll is very nearly 1:1 with tyre camber change. As such, tuning the initial camber setting and the front rear ARB stiffness would be critical. At the time, there were a lot of people chopping in GrpA cars for the first of the hand-me-down WRC cars,
Edited by Max_Torque on Sunday 29th September 13:20
The process of making the kevlar panels, how complex was this? Did you have to make your own moulds and tooling? Very impressive!
With the cage, surely a butchered/hybrid cage will no longer be MSA/FIA approved? How do you get around this?
Finally with the suspension... How do you control the camber change with a single strut and wishbone pivot type? Is the camber just described by the radius of the wishbone travel about the pivot and you are stuck with that? Do current WRC cars still use single strut and wishbones front and rear?
So, with plans sorted (ish) the butchery started!
The car was stripped back to a bare shell, and all the original mechanicals / suspension etc disposed of, then the roof panel was removed to help with the cage install (had to come off anyway as unfortunately the original had a sunroof hole in it).
(apologies for the poor photo quality, the early pics are scanned in from film!)
Checking clearance between steering column/pedal box and engine, especially the intake system. Due to the unavailability of high ratio RHD steering racks (WRC cars are LHD!), it was obvious the car would have to be LHD, not a problem as my daily at the time was an Integrale Evo ;-)
Left over volvo strut used temporarily to place a front wheel in place, allowing estimation of track width and wheel clearance to shell hard points. Also, the rollcage hoops have been trial fitted:
Originally i experimented with a Cosworth cast ally front subframe, seen in the this pic, but it proved to be unworkable and resultant suspension geo would have been poor at low ride heights. Also shown are the "banded" front turrets, used to lift the suspension top mounts up further into the shell to supply some much needed extra travel. Luckily, the front wheel houses are quite generous and little modification was required to the inner steelwork.
The ex volvo spec engine was dropped into the hole to see how far back and down it could be mounted. Unfortunately the F7 engines are long stroke and hence quite tall, so it was immediately obvious that a very low profile dry sump system would be required to get the engine low enough:
It became clear that a low mounted engine, tilted to the right (passenger side) would allow for the lighter intake system (later very light as it was re-made from carbon fibre!) to be lifted up above the pedal box and steering column, and the heavy turbo and exhaust manifold to be dropped downwards, allowing for a decent length exhaust primaries, and a nice straight exit run for a big bore exhaust system down the transtunnel.
Accurate measurements where taken from shell hard points for subframe mountings, and lots of measurements and head scratching occurred for things like bulkhead cutting and rear floor mods to accept the differential / gearbox etc.
The car was stripped back to a bare shell, and all the original mechanicals / suspension etc disposed of, then the roof panel was removed to help with the cage install (had to come off anyway as unfortunately the original had a sunroof hole in it).
(apologies for the poor photo quality, the early pics are scanned in from film!)
Checking clearance between steering column/pedal box and engine, especially the intake system. Due to the unavailability of high ratio RHD steering racks (WRC cars are LHD!), it was obvious the car would have to be LHD, not a problem as my daily at the time was an Integrale Evo ;-)
Left over volvo strut used temporarily to place a front wheel in place, allowing estimation of track width and wheel clearance to shell hard points. Also, the rollcage hoops have been trial fitted:
Originally i experimented with a Cosworth cast ally front subframe, seen in the this pic, but it proved to be unworkable and resultant suspension geo would have been poor at low ride heights. Also shown are the "banded" front turrets, used to lift the suspension top mounts up further into the shell to supply some much needed extra travel. Luckily, the front wheel houses are quite generous and little modification was required to the inner steelwork.
The ex volvo spec engine was dropped into the hole to see how far back and down it could be mounted. Unfortunately the F7 engines are long stroke and hence quite tall, so it was immediately obvious that a very low profile dry sump system would be required to get the engine low enough:
It became clear that a low mounted engine, tilted to the right (passenger side) would allow for the lighter intake system (later very light as it was re-made from carbon fibre!) to be lifted up above the pedal box and steering column, and the heavy turbo and exhaust manifold to be dropped downwards, allowing for a decent length exhaust primaries, and a nice straight exit run for a big bore exhaust system down the transtunnel.
Accurate measurements where taken from shell hard points for subframe mountings, and lots of measurements and head scratching occurred for things like bulkhead cutting and rear floor mods to accept the differential / gearbox etc.
Next steps was lots of CAD work, unfortunately in only 2d, as back then, 3d packages were the preserve of richer people than I.......
Initial schemes soon showed that anything using road based uprights was simply not going to work at low ride heights, and was unlikely to provide enough strength and stiffness in a competition environment:
That pretty much forced an (expensive) move to pukka rally parts, in this case, FORD escort WRC uprights:
FRONT:
REAR:
With Proflex supplying their low friction 4way adjustable remote resevoir struts, the geometry of the subframes and support components could now be optimised:
By this time i had already lost count as to the number of custom CNC'd parts required to optimise this design, and i was really only just starting!
First trial run fabricated parts were made to check fit and establish there suitability, and as usual lead to immediate changes and modifications. Originally i planned to use a Ford based rear differential, and the first rear subframe was designed to incorporate that:
As parts arrived, they were fitted and checked, here the front struts and uprights:
It became clear very quickly that a wider bodykit was going to be needed!
NEXT - Transmission and Torque tube forces major floorpan mods!
Initial schemes soon showed that anything using road based uprights was simply not going to work at low ride heights, and was unlikely to provide enough strength and stiffness in a competition environment:
That pretty much forced an (expensive) move to pukka rally parts, in this case, FORD escort WRC uprights:
FRONT:
REAR:
With Proflex supplying their low friction 4way adjustable remote resevoir struts, the geometry of the subframes and support components could now be optimised:
By this time i had already lost count as to the number of custom CNC'd parts required to optimise this design, and i was really only just starting!
First trial run fabricated parts were made to check fit and establish there suitability, and as usual lead to immediate changes and modifications. Originally i planned to use a Ford based rear differential, and the first rear subframe was designed to incorporate that:
As parts arrived, they were fitted and checked, here the front struts and uprights:
It became clear very quickly that a wider bodykit was going to be needed!
NEXT - Transmission and Torque tube forces major floorpan mods!
Trtj said:
The process of making the kevlar panels, how complex was this? Did you have to make your own moulds and tooling? Very impressive!
Unfortunately i haven't got many pics of this bit, as sticky, smelly, resins and cameras doesn't really go together! But basically, i reworked the metal work by welding in sections, and then used fibreglass cloth, body filler, expanding foam, and even chicken wire to form plugs of the shape of the wings, in place on the car. Then i took from this a female fibreglass mold. From those molds i made the actual parts from kevlar cloth. It's not difficult, but it is time consuming, and getting a good finish and good surfacing takes time. If i did it again now i'd go straight to 3d CAD and foam milling to make the plugs! (quicker, and much more repeatable)Trtj said:
With the cage, surely a butchered/hybrid cage will no longer be MSA/FIA approved? How do you get around this?
The cage was approved by SD after inspection. As the main hoops are original, and only the "straight" bars changed the MSA had no issues with the mods. if you were to modify the bent components it would be much more difficult to claim the original homologation still stood.Trtj said:
Finally with the suspension... How do you control the camber change with a single strut and wishbone pivot type? Is the camber just described by the radius of the wishbone travel about the pivot and you are stuck with that? Do current WRC cars still use single strut and wishbones front and rear?
Pretty much, you don't! Some tricks are availible, like using lots of castor to help with camber gain at high steering angles, but generally speaking you can't do a lot about it. For a circuit car, that experiences high lateral G, it would not be optimium, but for a much lower loaded rally car, the other virtues (strength, simplicity etc) win through. Pretty much all the WRC cars use struts at both ends for those reasons.Little video taster:
Start-Rev-ALS
Sorry, not much, will get some proper footage soon!
(CAUTION: contains gratuitous Antilag Action........ ;-)
Start-Rev-ALS
Sorry, not much, will get some proper footage soon!
(CAUTION: contains gratuitous Antilag Action........ ;-)
Max_Torque said:
Little video taster:
Start-Rev-ALS
Sorry, not much, will get some proper footage soon!
(CAUTION: contains gratuitous Antilag Action........ ;-)
I'm liking the Aston Martin brake calipers... Start-Rev-ALS
Sorry, not much, will get some proper footage soon!
(CAUTION: contains gratuitous Antilag Action........ ;-)
PS: get Mr Harris to do a video with it when it's really a runner.
Edited by AER on Wednesday 2nd October 03:01
Looks & sounds amazing 
seeing the video shows the amount of skill & engineering put into the build can't wait to see this finished & read further build details.
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