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-   -   hpde inspectors/instructors anyone?? I got some questions?? (https://www.rx7club.com/race-car-tech-103/hpde-inspectors-instructors-anyone-i-got-some-questions-347868/)

obviousboy 09-13-04 11:03 AM

hpde inspectors/instructors anyone?? I got some questions??
 
I have my first HPDE on Nov 8th at limerock in CT and I had a couple questions about my car and passing inspection.

When I first bought the car I hoped to keep it stock but everything in it was having an issue or issues.... heres what I did to it :(

The two major things I can think of interms of doing an HPDE

The ABS has been removed (replaced with brake balancer)
The power steering has been removed (line looped)

ABS was acting entirely to wierd after my car sat for 5 months in my driveway, when I drove it for the last time before pulling the engine out, it was kicking in way to early (a bump was setting it off). I did some reading and that wasnt normal behavior and since I had larger problems (a blown engine was up on the list) I decided to remove it and install the Brake Balancer..I made all my own lines (correctly) nothing leaks and everything checks out fine, I am currently am still trying to get the balancer to be setup correctly.

The PS was removed due to the tensioner bolt hole being broken on the back side (missing about 1/3 of the hole) this wouldnt let the pulley tighten down all the way and inturn was shredding belts...


Now thats the major things, heres the other 2

No working speedometer
No door lactching hinge for the gas tank (door swings open, held shut with tape)

I must have wacked or busted the VSS when I was working on my tranny over the winter. I just removed the entire console and all those lines checked out so im slowly working and checking everything back to the VSS.

Thanks guys

rynberg 09-13-04 11:57 AM

Fix the gas lid. Some groups will not let you run with a gas lid taped closed.

None of your other issues have anything to do with track safety, so they shouldn't be a problem.

obviousboy 09-13-04 12:13 PM

ok good to hear..thanks man

macdaddy 09-13-04 12:25 PM

1) Brakes. I presume you're talking about a brake proportioning valve. Most racing organizations don't allow ABS anyway, so not having it isn't a problem, as long as your brakes are solid. Some time spent before you get to the track to get the bias right would be well spent - use the tires you'll have on track, get them and the brakes warm, then do some threshold stops someplace safe. If you can have someone outside the car (ideally one person on each side) help you figure out which tires are locking up first, this will go a lot quicker.
2) Taking off the PS is definately OK.
3) You should be using your tach, not your speedometer, on track, anyway. Again, most race cars don't have speedometers.
4) You definately don't want your fuel filler lid flapping in the breeze. Fixing it is best, but if you can't get the part(s) in time, you could just remove the door. What is important in tech is that the fuel filler cap itself is secure.

obviousboy 09-13-04 12:30 PM

Thanks macdaddy,

Yeah Im still trying to dial in the best feel with it, I was also told to have the rears lockup just before the front, is that correct (sorry to go off topic)

I just read in some other threads on other forums that some inspectors dont like seeing any modifications to the brakes (ie large brake kits etc) so I was a little worried about having that mod in there

macdaddy 09-13-04 01:51 PM

Ideally, you would like to set the bias so that all 4 tires lock up simultaneously. In reality, however, you can't "set it and forget it" across the range of conditions where you are threshold braking - uphill, downhill, off-camber, varying track temperature, different track surfaces, varying tire grip, etc. all influence what the bias should be - which is why many race cars have the proportioning valve in the cockpit so the driver can make adjustments during the race. However, as a starting point, you generally want the front tires to lock up just a hair before the rear - this is safer and more predictable.

The organization holding the HPDE should either have written technical requirements, or reference an external standard (like SCCA's GCR). Get the specs, and quit guessing. Different organizations do have different requirements.

Note that passing tech for an HPDE may be somewhat divorced from what your in-car instructor may say - and ultimately, s/he has the final say about whether they get in the car with you or not. Some of this has to do with the car, and a lot has to do with your attitude.

In general, most instructors feel that a student new to the track should learn how to drive their car the way it came from the factory before putting lots of mods and $$$ into it. In general, though, as long as you haven't significantly increased the power on your car without improving safety, suspension, or brakes, most instructors will accept some changes to the stock setup.

obviousboy 09-13-04 03:20 PM


Originally Posted by macdaddy
In general, most instructors feel that a student new to the track should learn how to drive their car the way it came from the factory before putting lots of mods and $$$ into it. In general, though, as long as you haven't significantly increased the power on your car without improving safety, suspension, or brakes, most instructors will accept some changes to the stock setup.


Thats why I have yet to do any form (other then the abs removal) of suspension or brake upgrade/mod...Besides not being able to take advantage of it, I really wanted to learn how the car felt.....

I did do the bolton mods, but still dont even bring most of them into play, my boost is still dialed in at 7psi :) ....

rpv 09-13-04 10:05 PM

hi
the pca and bmw hpde schools here require you to bring the car to a shop that is on their approved list to get checked out before a school. so you may want to check. the on;y part i don't like is the brakes bias, it can be a pain to set right.

my 2 cents

good luck let us know how it goes
rob

alberto_mg 09-13-04 10:17 PM

hey dude. running w/o abs is fine, but do you need a brake bias valve? won't the brakes be biased by themselves w/o abs? i guess you removed the whole unit...

regarding bias, you definitely do not want the rears to lock up first. think of it this way - on track much of your breaking is threshold breaking going into a turn. the last thing you want is more bias to the rear. it will spin you faster than you can imagine.

furthermore i think break bias and lockup might be dependent upon weight transfer and load. breaking in a straight line all the load is on the front wheels. breaking ina corner will shift the weight to different corners of the car and affect which wheels will lockup first. you'll have to play with it.

i'd recommend playing with it with hard stops on the street on a dark unused road and set it up with a slight bias to the front. then try hard breaking in some kind of sweeper to see how it feels as well.

i was able to fix my gas filler door by playing with the striker. give it a shot. i don't think the filler door will be much of an issue though. send nasa an email and a pic just to make sure though. the last thing you wanna do is go there needing to work on your car.

i miss lime rock...


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