Jump to content
SAU Community

Recommended Posts

Just starting to do a few track days.  My track has 3 long straights followed by hairpins so i dont' wanna be diff locking all time.

With the heel and toe technique -  Ive got a r33 gts-t with evo brembo front and rear.  The brakes are so good, it only takes a light touch at the top to get it to stop.  My accelerator pedal is much lower down than the brake so im having big problems with heel and toe to downchange gears (im not even getting it close)

I was going to put a layer or two on the accelerator pedal to try and the get the same sort of height, but even with this the brakes are heaps sensitive.

Any suggestions ?

thanks

Link to comment
https://www.sau.com.au/forums/topic/473788-pedals-heel-and-toe/
Share on other sites

Provided you could still stroke the brake master cylinder to the stop, is there any adjustment left on the clevis and pedal stop to lower the brake pedal a bit?

You have to adjust the pushrod and stop (Probably the brake light switch) at the same time. If you just adjust the stop you wont uncover the fluid passages in the top of the cylinder that go to the reservoirs. Basically the piston in the master cylinder has to be right at the top of its stroke when your foot is of.

I only put that bit in as a lot of folks don't know about it and it is important to get right.

2 hours ago, R377 said:

Just starting to do a few track days.  My track has 3 long straights followed by hairpins so i dont' wanna be diff locking all time.

With the heel and toe technique -  Ive got a r33 gts-t with evo brembo front and rear.  The brakes are so good, it only takes a light touch at the top to get it to stop.  My accelerator pedal is much lower down than the brake so im having big problems with heel and toe to downchange gears (im not even getting it close)

I was going to put a layer or two on the accelerator pedal to try and the get the same sort of height, but even with this the brakes are heaps sensitive.

Any suggestions ?

thanks

If you only need a light touch on the brakes to stop you are not going fast enough or braking too early!

  • Like 1
If you only need a light touch on the brakes to stop you are not going fast enough or braking too early!
Or youve removed ABS and your brakes aren't balanced properly and lock up exceptionally easy
  • Like 1

Are your pedals standard?

Do you wear proper shoes when on the track rather than your normal Doc Martins or whatever people wear nowadays.  They make a huge difference.

Try practicing with no shoes on.

If you are consistently locking rears the chances are your bias is out. If you brake hard without the car in gear does it lock up the back end?  If the answer is yes it may well be the case.  Quickest fix is then to get some rear pads with a lower coefficient of friction.

Edited by djr81
  • Like 1

Thanks for the replies guys.  I have a series 2 r33 gts-t which i thought were all ABS ?  Actually just googling not all have ABS like i thought....  Mine does not have ABS.  I haven't touched it but maybe somebody else did.  The front right does lockup before both front lock up.  I have played around the ride height abit but not tracked it or driven it in anger yet...

I wear normal sneakers that are worn on the soles.  I also had a play around in the garage wearing crocs as same as the sneaker - not much grip but a thinner sole.

I have standard pedals.  I have just installed the evo brembo front and rear kit 350mm f and r

I would put up a different perspective (Especially if you are not generally locking them up)

Firstly, what they have posted above, shoes. Race boots are not all that costly, buy some if you can afford to. They really do make a difference, apart from anything else the heels will be rounded where many shoes have a much more square heel and it makes things easier, as well as the softer soles helping with feel. The disadvantage is that the thin and soft soles wear out a lot faster than a pair of runners.

Second is more of a comment. I found the Skylines brakes with good pads (HR31 with R33 GT-R Brembo fronts and GTS-T rears) to have far too much initial bite which made them easy to lock up, particularly in the wet, you literally had to be on your toes. I went to a 27mm (I think) master cylinder from a Navara and adjustable bias valve to increase the pedal effort but I still did not like them much. I am in the process of fitting a full pedal box to mine to get rid of the booster completely. I was using Project Mu RC09 pads as one track the car is run at is seriously hard on the stoppers and anything less tended to run out of pad fade wise by the end of a three hot lap sprint and consumes the pads at a silly rate. That is on the RAAF base at Sale and having driven both it is as hard on the brakes as Mallala.

13 hours ago, R377 said:

Thanks for the replies guys.  I have a series 2 r33 gts-t which i thought were all ABS ?  Actually just googling not all have ABS like i thought....  Mine does not have ABS.  I haven't touched it but maybe somebody else did.  The front right does lockup before both front lock up.  I have played around the ride height abit but not tracked it or driven it in anger yet...

I wear normal sneakers that are worn on the soles.  I also had a play around in the garage wearing crocs as same as the sneaker - not much grip but a thinner sole.

I have standard pedals.  I have just installed the evo brembo front and rear kit 350mm f and r

If you are consistently locking one side and not the other your corner weighting is probably out.  If you are locking one axle and not the other your bias is out.

If you have too much bite then change pads.  Ferodo DS2500's aren't known for being bitey.  What brand pads do you have?

Find some non fire proof racing shoes shouldn't cost you much more than $100 or so.  Fancy ones start at twice that.

For casual type driving shoes, I have been a big fan of the Puma 'Cat' series (speed cat/drift cat etc). Had at least 5 pairs (and still have 2 in circulation) over the last 5+ years. They must be nearly due another new release soon (I hope).

Of course might not be suitable depending on what kind of events you are doing.

Kart shoes are another option.

I'm not familiar with the accel setup, but it is possible to adjust it up instead of the brakes down?

  • Like 1

If your front right is locking up on its own then you need to fix the brakes before worrying about heeling and toe-ing.  If it locks up on the street it will probably throw you off the track at speed.

19 hours ago, R377 said:

...

I have standard pedals.  I have just installed the evo brembo front and rear kit 350mm f and r

Ok so 350mm front and rear but I'm guessing you're using a smaller caliper in the rear yes? I'd imagine using the large 4-pot front calipers in the rear that would cause all kinds of funky brake bias issues with standard MBC/ABS/lines...

The fact that you have one side locking up first doesn't sound great, I would get the system checked by a brake specialist.

With the pedals, what I did with my old Monaro was to buy a second hand accelerator pedal and bend that out so it was more level with the brake pedal. That helped a bit but the stock pedal positioning in the R34 is still better. I wouldn't go modding the brake pedal under any circumstances, and obviously avoid anything that can come loose or catch your footwear.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • @Haggerty you still haven't answered my question.  Many things you are saying do not make sense for someone who can tune, yet I would not expect someone who cannot tune to be playing with the things in the ECU that you are.  This process would be a lot quicker to figure out if we can remove user error from the equation. 
    • If as it's stalling, the fuel pressure rises, it's saying there's less vacuum in the intake manifold. This is pretty typical of an engine that is slowing down.   While typically is agree it sounds fuel related, it really sounds fuel/air mixture related. Since the whole system has been refurbished, including injectors, pump, etc, it's likely we've altered how well the system is delivering fuel. If someone before you has messed with the IACV because it needed fiddling with as the fuel system was dieing out, we need to readjust it back. Getting things back to factory spec everywhere, is what's going to help the entire system. So if it idles at 400rpm with no IACV, that needs raising. Getting factory air flow back to normal will help us get everything back in spec, and likely help chase down any other issues. Back on IACV, if the base idle (no IACV plugged in) is too far out, it's a lot harder for the ECU to control idle. The IACV duty cycle causes non linear variations in reality. When I've tuned the idle valves in the past, you need to keep it in a relatively narrow window on aftermarket ecus to stop them doing wild dances. It also means if your base idle is too low, the valve needs to open too much, and then the smallest % change ends up being a huge variation.
    • I guess one thing that might be wrong is the manifold pressure.  It is a constant -5.9 and never moves even under 100% throttle and load.  I would expect it to atleast go to 0 correct?  It's doing this with the OEM MAP as well as the ECU vacuum sensor. When trying to tune the base map under load the crosshairs only climb vertically with RPM, but always in the -5.9 column.
    • AHHHH gotchaa, I'll do that once I am home again. I tried doing the harness with the multimeter but it seems the car needed a jump, there was no power when it was in the "ON" position. Not sure if I should use car battery jump starter or if its because the stuff that has been disconnect the car just does send power.
    • As far as I can tell I have everything properly set in the Haltech software for engine size, injector data, all sensors seem to be reporting proper numbers.  If I change any injector details it doesnt run right.    Changing the base map is having the biggest change in response, im not sure how people are saying it doesnt really matter.  I'm guessing under normal conditions the ECU is able to self adjust and keep everything smooth.   Right now my best performance is happening by lowering the base map just enough to where the ECU us doing short term cut of about 45% to reach the target Lambda of 14.7.  That way when I start putting load on it still has high enough fuel map to not be so lean.  After 2500 rpm I raised the base map to what would be really rich at no load, but still helps with the lean spots on load.  I figure I don't have much reason to be above 2500rpm with no load.  When watching other videos it seems their target is reached much faster than mine.  Mine takes forever to adjust and reach the target. My next few days will be spent making sure timing is good, it was running fine before doing the ECU and DBW swap, but want to verify.  I'll also probably swap in the new injectors I bought as well as a walbro 255 pump.  
×
×
  • Create New...