S4 - First track day, some questions
 

Finally got a chance to take my 87 GX out to an auto-x event yesterday. I had a blast but I am wondering a few things:

1) During slaloms occasionally the oil level warning light would come on. The oil level is presently right at the full line. Should I be over-filling it slightly when I go to auto-x events? I rode in another rx-7 and his light came on way more frequently that mine, but that doesn't make me feel much better.

2) How do you fit in this thing with a helmet on?! I had to lean the seat back so far I could barely reach the wheel with both hands. I am only 5'11" and have a relatively small helmet. I may need to lower the seat somehow, or add a spacer to the steering wheel.

3) What sway bars do you guys recommend? I presently have Tokico blue's with racing beat springs and I was getting a lot of roll in the corners. If it matters at all I am running Sumitomo HTR-200's in stock size (185/70R14) for tires.

1- if it's just the level light and not the pressure light, I would ignore it.

2- Depends on if you need an adjustable seat, and how much headroom you need. In the race car we bolt an alluminium seat to the floor

3- Springs have a bigger effect on the Auto-x course than sway bars, due to the constant transitions. If it is a daily driver how stiff do you want to go on the springs.

Not a daily driver at all, I have a newer car with many more creature comforts to drive every day (that gets way better mileage), the rx-7 was bought specifically for auto-x and lapping days, although I do have to drive it to/from the track when I am using it so I can't lower it any more than I have already.

I am not looking to change the springs again since I think if I go any stiffer the tokico blue's will just give up and so I'd have to change shocks and springs at which point I'd probably be looking at coilovers which will completely blow my budget. Would sway bars just be a big waste of money then?

As for the seat, I suppose I don't need an adjustable seat, but the factory seat already mounts pretty low to the floor, how much lower can I go?

Your sun roof is killing the headroom.

I had the same problem of fitting in my fc with a helmet on, and using stock seats. I ended up buying a race bucket, i went from zero to 1.5" of headroom with a helmet on. The stock seats seem low, but they arent actually low to the floor.

You can pickup a used race seat that mounts really low for fairly cheap.

I think I will end up replacing the seat with a racing seat. Mine is split all over and stained and otherwise completely worn out so I have no opposition to replacing it other than cost. It would be nice to have a reclining seat but if the seat is comfortable that is not a necessity. It would also be nice to be able to use the sliders, or at least some sliders, since I have a bit of a tough time getting my legs under the wheel when getting in/out and I really don't like falling on my face. Considering this, what would you recommend for seats? Am I asking for the impossible here?

As for the sunroof I suspect that is making a difference. I took a ride in another rx-7 without a sunroof and had about 1" of headroom to spare, then again his seats may have been adjusted differently and I didn't have to adjust my seat to reach the wheel so that could play a factor as well.

I have checked the rules regarding the class I am currently in and what modifications are allowed, and if I go to a coilover setup (the only way I see to go up very far in spring rates from where I currently am) it would change my class, however changing both front and rear sway bars are allowed. Considering this as well, would it be worth throwing a set of bigger sway bars on the car?


One last thing I think played a big factor in how the car handled, I just got new tires on it, Sumitomo HTR-200's, in 185/70R14 and I was running them at 32psi, but reviewing the pics from my runs they seem to be tucking under the wheels pretty far and I was running past the corners of the tread. Now, I know some of that is unavoidable since they are 70 profile tires, but do you think bumping the pressure up to 35 or 38psi might be beneficial here?

Thanks for all the advice so far, and thanks for putting up with an auto-x noob's questions :)

1) In my race car, I run 1.5L over full. Make sure you have a good crank case vent system if you do this.

2) You can't. I'm 6'4" and i can't fit into an FC with a helmet on with a stock seat. Take the seat out and put in a kirkey Road course seat with decent bolsters. Unfortunately, they do not recline but you will net a huge amount of headroom. Baring that, you can get the knock-off "racing" seats off ebay or the like. Not as good but they do recline and fit aftermarket sliders.

3) Watch your choice of swaybars. I suggest changing springs as someone has already noted because you don't want to lift the inside tire. You loose whatever grip that tire provided when on the pavement.

Your choice of tire will impede your performance on the track, either auto-x or lapping day. With street tires, you need to have a high pressure to make them work. More often then not, they need to be over-inflated to stop them from floundering under the rim. Also, if you plan on using them for lapping day, I suggest you get a minimum of 'V' Speed rating. Some tracks may verify your tires and may not let you race unless you have a 10% fluff zone on your speed rating. No-one wants a blow out on the track!

I have run this exact course before on lapping days in a higher powered similarly weighted car and never exceeded 185km/hr. My tires are H rated so I should have some breathing room on their speed (rated to 210km/hr, I expect ~175km/hr). Thanks for the tip there :)

Can anybody recommend a particular racing seat and slider set that would be significantly lower than the stock seat? It is really tough to judge over the internet and in pictures what might fit :(

Nobody can recommend a reclinable seat and slider set that will sit lower than the stock seat?

any of the purchasable reclining seats with sliders and mounting brackets dont knock much height off vs the stock setup if any at all.

I am 6'4" and i have to recline a street seat pretty far in a sunroofed FC to fit in with a helmet.

Your realistic options are, fixed seat with race style side brackets or ditch the sunroof and have the roof welded shut...(thus have to source a non-sunroof headliner...)

I am not willing to sacrifice the sunroof for 2 reasons:
1) I like it, this car is for auto-x only and I want to be able to enjoy it later if i keep it, or be able to sell it if I don't
2) it would change the class I am racing in and that would make me less competitive.


If I have to go fixed seat that is a much more acceptable compromise (providing I can keep sliders at least). Does anybody have any recommendations for a fixed seat that would give me about 2 inches more headroom than the stock seat? (and also allow me to keep the stock seatbelt)

taking your sunroof out changes your race class?! Interesting...

Im just giving you the options i know of....im not aware of any slider mounts that will drop the seat significantly...

Any race bucket will work, sparco makes good floor brackets for the 86-91 rx7, but if you want maximum head room, be prepared to bend, and/or weld a little.

The sparco brackets are a great base to modify if you want the sidemounts as close to the floor as possible.

If you run sliders, you are losing 1" of head room...keep that in mind.

Agreed.

Your quest for headroom is going to be a tough one if you want sliders.

How would changing the roof panel change your class? RX7's came without sunroofs in a number of years so a non-sunroof RX7 is still considered stock. The panel could be changed completely, like I did on my car to save weight or just pullout the motors and tracks and clamp it in place. That leaves the panel in place for when and if you want it to work again and yet gives you an additional 1" or so of headroom.

I have a very long torso and have tried everything to get a comfortable seating position in my car with a helmet on. I ended up reclining the seat to the point that I am almost in a reclining position (like a formula car) and cutting in to the transmission tunnel to allow me to sit closer to the centerline of the car. I also shifted the steering column and extended it to fit the new position.

Finally, I have an RX7 racecar that I fit into. You may need to think outside the box a bit as well to fit into your car properly.

Eric

in SCCA solo if you're going to remove the sunroof I think in order to be legal you'd have to replace the whole roof skin and install a sunroof-less roof liner.I ended up reclining the seat to the point that I am almost in a reclining position (like a formula car) and cutting in to the transmission tunnel to allow me to sit closer to the

I assume this isn't the case with the OP car, but I know in my car it wasn't even offered without a sunroof (S5 TII) so in some classes I wouldn't be able to remove it at all...

as far as body roll I'd slap on the big ST front sway bar and keep the stock rear and add some spherical end-links to replace the plastic stock ones. that should be a big improvement. after that you're going to have to increase spring rate, maybe get some ground controls with some nice universal springs.

also, what tire pressures are you running? with those wheels/tires you're probably going to have to run really high to stay off the sidewalls. like 50+psi

Take your stock seat apart and see if you can shave off some of the lower padding. I am 6' and have just a bit of rub on the sunroof of my GXL. I sit as upright as possible too. You must have a long torso.

i got a used buddyclub P1 with the super low down mounts for $300 im now sitting 1.5 inches lower than the stock seat

1. the oil level plunger will move around with high G forces, especially on left turns.
3. i don't know what class you're in but even in stock class the front bar is free, so you should do that. also it sounds like you might have a 4 lug/base model car, and in that case the upper model s4 and all the s5's have bigger stock swaybars, so that might be an option too.

3a. you also want to try to get as much negative camber in the front suspension as you can

yeah it helps to go sit in a bunch of seats. personally i have found if you buy a good seat, they are comfortable and you don't need to recline them. i think most of the side mount seats will mount at about the same height, because the bottom of a seat is pretty much the bottom of a seat

The reason the oil level goes off is due the the position of the oil filler tube.

I am sure your buzzer only goes off on right turn only right?

In left hand turn the oil hits a wall and the bottom of the block. Your fine.
ON right turns the oil will fly up the oil filler tube making the buzzer go off and possibly sucking up air. You should consider a baffled pan or a baffle plate for the stocker.

Sorry I forgot about this thread for a little bit there

Thanks for all the input guys! :)
To answer some of the questions/guesses in here:
Yes it is a base-ish 4-lug car. It is a GX model, which if I understand correctly is a canadian only thing. It has A/C, sunroof, power steering, but 4-lug wheels, manual windows and no LSD. I am considering doing a 5-lug swap and going to slightly bigger wheels (15") with much better tires next year but to keep my class the same I'll need to swap the diff and associated bits as well as possibly install power windows, I'll worry about it once I get better at driving.

I have had the pleasure of doing a second event in this car and now have a bit more experience to talk about and more questions to ask.
Regarding the tire pressure, I ran my first event at 32psi, then for the second event I pumped them up to 45psi and did 4 runs (of 7), feeling that traction was better than last event and not having an air pump with me at the track I decided to let some air out to see if I had gone past the sweet spot or not so I dropped them down to 40psi for the final 3 runs (cold pressure, there was 2 1/2 hours between sets), traction was noticeably worse at 40psi. Based on this, 50psi sounds like it might be the right way to go as I am still rolling off the corners and onto the sides of the tread at 40psi (I didn't chalk them at 45psi to check so I don't know for sure there). The tires are rated to 51psi so I'll give 50 a shot for the next event.

The oil level light comes on during hard right hand turns, and on turns in both directions during a slalom, but the oil pressure warning never goes off and the oil pressure gauge doesn't drop even on longer turns. I'm going to try bringing the oil level up a bit for the next event as the issue is definitely getting worse (my first event it was ~0.25L over full, my second event it was exactly on the full line). I'll try 0.25L over-full again and bring it up a touch more if necessary at the track. I hadn't considered baffling the pan, but it is something I will consider going forward, any baffles in particular that you would recommend?

Deleting the sunroof would require me to do a swap to another trim level which did not have a sunroof. I can't find good details on what trim levels those would be and likely that swap would end in me buying parts that would cost more than just swapping the seat. Since the stock seat is ripped in many places already I am not against getting rid of it, but I am having trouble locating a good replacement locally without knowing exactly what will fit or help the problem.

I think I am going to adjust the alignment on my car to try to get a bit better traction in the corners. I have no idea how the alignment is set right now, except that it appears to have 0 toe and a small amount of negative camber front and back. I'm running another event July 17 and doubt I'll have time to check the alignment before then, but with any luck I'll verify and adjust it the week after that. After doing a lot of reading I am going to adjust the alignment to the factory limit for toe-out, and as much negative camber and caster as I can get while remaining even on both sides.

Regarding sway bars I definitely feel like I need a stiffer bar, at least in the front. I am racing in CSP so I am free on both front and rear bars. I have racing beat springs on all 4 corners and I was considering getting their front and rear bars (on the assumption that they would design them to play well with their springs). I also am free on suspension bushing material so I was considering a poly kit for the front and back since my rear front control arm bushings are showing signs of age. The poly kits usually come with sway bar end links as well, would it be a big difference going from these to spherical bushings there?

I am going to hit up a couple of local racing shops and see what they have for seats that I can hop in. What brands of seat rails will mount to the stock holes? (if any?) I don't think anybody local sells Buddy Club seats but I'm going to check.

Thanks again for all the advice :)

racing beat offers the baffle plate.