High speed rear downforce

[Gulfstream]

Looking for a little less lift over the rear of my LCR. Would this be an improvement?

http://www.dcp-shop.co.uk/2309S-Seat-Leon-WRC-rear-spoiler?osCsid=1314189056f616285ef2998a9bf3f5ee

 

[ReDBull]

Have you thought about a flat floor and diffuser?
It's something I'm thinking about here's a thread for inspiration
http://www.clubgti.com/showthread.php?126104-Niges-2nd-MK2-Track-car-With-Aero-Megasquirt-and-ITB-s
Check out his home brew rear spoiler.

 

[Gulfstream]

Making a new floor is too much work for me. Im old and lazy.

 

[ReDBull]

Looking at that spoiler in the link I don't think it goes high enough up into the airflow. Have you thought about adding a wing onto the standard spoiler and or a gurny flap?
Are you running any front end down force at the moment?

 

[BigJase88]

Are you running a rear arb!?

With a neuspeed 28mm lift off oversteer is almost zero as the back end grips where as before it used to let go!

Cornering speed is up a good 20/30mph depending on corner

 

[285cupra-matty]

+1 on the RARB i can hardly get lift off now even when trying and i still have one more adjustment to go.

just googled the gurney flap as well worth a go is you can fabricate one up. Or buy one dont know if thats possible or not.

 

[Gulfstream]

I do have a 28mm rear arb and it made zero difference on my setup. High speed corners felt identical before / after. Might be related to my coilovers being very stiff... idk

Front I have upgraded arb and S3 strut brace.

Will look into APR universal canards to bolt on the front bumper sides but from previous trackdays I felt the rear starting to tip toe at high speed so I feel rear downforce is more urgent than front.

Also I run slick up front this season.

 

[Gulfstream]

APR front canards:

http://aprperformance.com/index.php?option=com_content&task=view&id=85&Itemid=44

Gurney flap might be easiest way to go...

 

[285cupra-matty]

could be that your running sticky tyre's on the front and not on the back? have you run it with 4 slicks on ?

 

[BigJase88]

I do have a 28mm rear arb and it made zero difference on my setup. High speed corners felt identical before / after. Might be related to my coilovers being very stiff... idk

Front I have upgraded arb and S3 strut brace.

Will look into APR universal canards to bolt on the front bumper sides but from previous trackdays I felt the rear starting to tip toe at high speed so I feel rear downforce is more urgent than front.

Also I run slick up front this season.

Thats strange

My neuspeed made one hell of a difference, im on kw coilovers too so not rubbish coilovers either??

The issue might be your uprated front arb. If you revert back to standard the rear grip will increase

 

[Gulfstream]

could be that your running sticky tyre's on the front and not on the back? have you run it with 4 slicks on ?

Last season I ran with 4 semislicks. Major understeer

This time Ill do streetires rear and slick up front. The need to increase rear downforce is felt 100mph + corners. (Nurburgring)

Yes I know slicks all around would make it more stable but need to combat understeer in medium / lowspeed corners.

 

[ReDBull]

APR front canards:

http://aprperformance.com/index.php?option=com_content&task=view&id=85&Itemid=44

Gurney flap might be easiest way to go...

Canards don't generate that much down force. Think of them more as vortex generators that help the air flow around the front wheel arches and down the side of the car. An air dam, flat floor and diffuser are the way to go with your car.
Down force front and back needs to be balanced and it's much easier to generate front end down force. You'll get more benefits from a flat floor and diffuser than 'just' more down force. Think also less drag. You can't be that much older than me and I plan to spend a bit of time this summer on my back with some big bits of cardboard.
If you haven't have a look through that thread I posted a link to, it's impressive stuff!

 

[Chris4877]

Are you running a rear arb!?

With a neuspeed 28mm lift off oversteer is almost zero as the back end grips where as before it used to let go!

Cornering speed is up a good 20/30mph depending on corner

+ a million on that comment, mines been on 4 days, it's an epic mod

 

[ReDBull]

+ a million on that comment, mines been on 4 days, it's an epic mod

Have you checked out Gulfstream's car on YouTube? It's epic.

 

[Chris4877]

No, what's it called

 

[Gulfstream]

Canards don't generate that much down force. Think of them more as vortex generators that help the air flow around the front wheel arches and down the side of the car. An air dam, flat floor and diffuser are the way to go with your car.
Down force front and back needs to be balanced and it's much easier to generate front end down force. You'll get more benefits from a flat floor and diffuser than 'just' more down force. Think also less drag. You can't be that much older than me and I plan to spend a bit of time this summer on my back with some big bits of cardboard.
If you haven't have a look through that thread I posted a link to, it's impressive stuff!

Yes I did look tnx.... It certainly would help doing all that but I think Ill go with the gorney flaps on the rear spoiler to push the rear down a bit rather than trying to create a vacuum underneath the car. Also this takes a few hrs and not a few months

 

[Gulfstream]

No, what's it called

http://www.youtube.com/user/oistein74/videos?view=0

not epic yet, but if I get below 8mins at the ring this year I'll agree

 

[Chris4877]

Haha

 

[hyphon12]

First thing I'd do is tweak your rear damper stiffness. I help a mate of mine with his rally car and we soften the rear stiffness when his back end gets lively and every small adjustment (usually softening) we do seems to improve the rear end grip, basically allowing the rear axle to stay flat for longer in hard cornering.

 

[Gulfstream]

First thing I'd do is tweak your rear damper stiffness. I help a mate of mine with his rally car and we soften the rear stiffness when his back end gets lively and every small adjustment (usually softening) we do seems to improve the rear end grip, basically allowing the rear axle to stay flat for longer in hard cornering.

My understanding is if you soften up the rear you'll induce more understeer. The biggest problem I have is a light footprint at the rear at high speed. I'm afraid this is an aerodynamic issue...

I have plenty understeer in medium/low speed corners already so.. don't need more of that