My Cordoba Coupe Trackday Car Project

[goble]

right not been funny at all but iv'e just read all of this thread and seen some of the images.
i would like to ask a couple of question's
1 what sort of power are you looking for?
2 what are you expecting it to rev to?
3 how reliable does it have to be? ie racecar trackday car or trackday and normal road car?
4 dont you think that your going to get flow problms with that 'air intake' ?
5 do you know what happens if you use longer or shorter trumpets?

 

[goble]

 

[m0rk]

You mean he should have an exhaust in the airbox

 

[goble]

dont even think that would help the way its going to flow. evn if you got the flow problems sorted out you are still forcing the air into the engine and unless you get it mapped to each use then it's going to be running lean as hell then it WILL go bang

 

[F2 Stu]

Ermmm - its by no means a finished item

Its not mapped yet and I'm working on pointing the trumpets down etc etc

 

[Feel]

Air doesn't get pushed into the engine, though, it gets sucked in.

Goble's diagram (which CFD package did you use ) indicates a point of pressurised air right where you want it...

 

[goble]

Air doesn't get pushed into the engine, though, it gets sucked in.

Goble's diagram (which CFD package did you use ) indicates a point of pressurised air right where you want it...

correct it doesnt it gets sucked in as you say but if the air is going to be directly flowed into the tb trumpets then the faster to go the more air will be forced in then will run lean, but if the intake was at the side it would suck.
the f2 car sucked air it was not forced through

 

[F2 Stu]

Thing is I can restrict the intake if needs be and theres quite alot of volume in the box too circa 5-6 litres I reckon...

Also trumpets breath in air behind themselves and its better to have this effect

 

[ibizacupra]

on the Elise, QED made a carbon airbox for its DTh bodies on K-Series.... and made it bigger and bigger and bigger until they ran out of physical room... and everytime it was bigger it made power/torque everywhere.
Rule of thumb a local bike tuner told me many years back (ok bikes not cars) but his advise was to make an airbox no less than x5 the engine cc.

Wideband gauge Stu.. make sure you have on in eyes view when running. dyno airflow will be different to on the road, so you will be able to make map adjustments based on actual roadspeed/airspeed when its done.

 

[RobT]

race teams spend no doubt tens if not hundreds of thousands of pounds making air boxes that enable positive pressure through forward motion - IT IS possible to force air into an atmospheric engine, its called ram air and virtually every superbike made uses it. But yes also needs proper mapping for - air temp sensor may go towards doing this but also a pressure sensor may also be required - not going to be possible to have maps adjusted for forward motion as the ecu wont know if its stationary or moving (at least not the ecu's that we use at this level). Like bill says, just check it with lambda once mapped stationary and make sure it isn't going lean when moving - it will be fine

as for "the F2 car sucked air, it was not forced through" dont think so, the airbox on the F2 car was a fantastic piece of design that I have no doubt created positive pressure

 

[F2 Stu]

Been looking at wideband guages - so many to choose from

Thanks for the advice people, its appriciated

 

[RobT]

innovate motorsports in US good for price

 

[F2 Stu]

http://www.innovatemotorsports.com/products/g2_gauge.php

Liking the look of that one, will fit in with the oil temp,oil pressure guages & pod Im looking at too

 

[ibizacupra]

VEMS also looks nice... (but cos its got integral egt too for turbo installs)

 

[F2 Stu]

on the Elise, QED made a carbon airbox for its DTh bodies on K-Series.... and made it bigger and bigger and bigger until they ran out of physical room... and everytime it was bigger it made power/torque everywhere.
Rule of thumb a local bike tuner told me many years back (ok bikes not cars) but his advise was to make an airbox no less than x5 the engine cc.

Apparently the bulkhead for the 'boot' has to be altered to get that in!

 

[F2 Stu]

Bit more work from today.

Trial fitted the box to check clearences around the grill

Takes up quite a bit of engine bay space! There's a bit more clearence I can exploit between the lid and the underside of the bonnet, will be making another lid to give more room around the trumpets.

Thats the metal work complete, only need to drill a hole for the air temp sensor.

 

[m0rk]

Just thinking..... engine movement's been considered?

 

[F2 Stu]

Yep, theres plenty of flex in the backplate and will be fixing sponge rubber 'buffers' in places.

Theres allways solid mounts if that fails lol

 

[ArosaRacer]

good work stu now im looking forward to your magic hands being worked on the other project

 

[F2 Stu]

Got convinced into making the lid out of GRP (fibreglass) and adding abit more room above the trumpets

First real attempt of doing any thing out of GRP and its suprising easy to get good results, put 3 layers on (~3mm thk) which gives a bit of margine to fettle/smooth out the rough bits.