FWD lack of front grip

Hi all. I race a Honda Integra DC5 in the UK and I'm struggling with what I believe to be front grip issues due to excessive tyre temperature however I'd welcome other opinions or any suggestions on how to manage the situation!

Details on the car:

- 1260kg with driver post race

- 177whp (dyno is notoriously unreliable so take with a pinch of salt!)

- 245/40/17 front and 225/45/17 Toyo R888R tyres (series mandated)

- 6 degrees caster, 4 degrees camber, and 10 minutes toe out at the front

- 2 degrees camber and 0 toe at the rear

- 8kg front and 16kg rear springs with Yellowspeed dampers

- Aiming for 30psi hot tyre pressures

At the start of the season the car felt fantastic to drive, mid-corner grip was great and I found I could place the car where I wanted and carry a good amount of apex speed. I would scrub the speed off early then use a low percentage of throttle to drive through the corner, increasing power as it went.

As the season has progressed I've struggled more and more to be able to get anywhere near the throttle during the corner as the front tyres would break traction and I would understeer. To help try and get some of the pace back I've tried a variety of different rear setups to get the rear to rotate more and give that sense of "balance" back, however I think this is probably the wrong avenue to follow? By doing this I'm not fixing the underlying issue of a lack of front end grip, I'm just making the rear looser to rotate more? Setups I've tried:

- Raising the rear ride height by 30mm

- Toe out at the rear

- 50+ psi rear pressures

Individually neither seemed to make a big difference, combined they made the car incredibly sketchy to drive and slightly beyond my skill level to manage.

This brings me back to my thought that I'm trying to fix the wrong problem, I need to understand why the front seems to have dropped off rather than manage it by making the rear rotate. I've made no changes to the front geo and the issue has been across multiple sets of tyres and wheels so I don't believe it's anything there.

The one thing that stands out to me is track / tyre temps. At the beginning of the year the track temp was low, I don't have the actual track temp values but the air temp at the first race was approx 7 degrees C. At my last race the air temp was approx 24 degrees C and the tyres were hopeless. Similarly I've noticed that morning sessions feel better than afternoon sessions.

My thought is that the increased track temp causes the tyres to go beyond their operating window. Other cars in the series don't seem to struggle as much as me however I'm one of the heaviest cars on the grid which is probably exacerbating the problem?

Does that sound like I'm on the right track? I'm going to buy a tyre pyrometer so I can start to record temps in more detail but in leiu of that data I was hoping someone could provide any guidance!

Does anyone have a suggestion on how to manage the tyre temps? I'm going to fit some brake ducting to try and vent the brakes better in the hope that'll help but I'm unsure of other another way to cool them down.

Thanks!

How are you tracking tyre pressure vs. temp? When the car is loosing grip, can you stop, measure the tyre pressures and if necessary drop them to your target hot pressures? Then go back out and see if that makes a difference. If so, then let the tyres cool on their own, and make that your new target cold pressure for the morning.

This problem is worse if using air from a compressor (particularly anywhere with humidity). Use dry-nitrogen to minimize the pressure rise with temp.

Lastly, check your suspension carefully -- a failing bushing or loose wheel bearings can slowly loose performance if the geometry in the corners is not what it was when the parts were fresh at the start of the season.

As David said, the bushing may be worn - not forgetting the ARB(s) - or there may be structural deformation/cracking/weakness developing..

What LSD are you using, could it be worn?

Try running the rears down to the minimum recommended by the tyre manufacturer, usually around 24 PSI, to increase the slip angle.

You may need to alter your driving style a little, to reduce the heat you're putting into the front tyres?

Thanks for the responses.

I'm not directly tracking tyre temp at the moment, only pressure. I've bought a tyre pyrometer to help me record temps as well as pressure to try and build up a bigger data set. The tyres gain approximately 9psi cold to hot and I check mid-session and adjust back to the target hot pressure if required.

I've thought about using nitrogen as an alternative to compressor air that I currently use, I may look more in to that.

I'll check the bushings although they were replaced at the start of the year so I'm hoping they should be ok!

LSD is a Kaz unit I believe.

I'll try reducing the rear pressures down. With previous experiements I've actually put them particularly high with the idea to reduce the contact patch of the tyre and thus reduce the rear grip but I haven't tried the other way, will do that.

Driving style is something I can work on. I think I'm pushing the car a little harder in to the corners to try and compensate for what feels like a lack of front grip, but perhaps that's just overdriving it now. I've tried to get the rear to rotate more on corner entry to try and ease the load on the front axle and help manage the tyres better.