fast drag cars

[badassbowtie]

I have a question for all the gusy running 11.00 or faster at the drag strip. Has NHRA required you to make any safety modifications to the independent rear suspension? I have read the rule book but dont know if it applies to Z-car rear suspension. I wanted to get real world input from tech inspectors.

[dr_hunt]

IMHO it depends on the track and the tech guy(s) there. Here at my hometown track Alb. National which is and NHRA the tech guy knows me, but he pretty much goes over the car and every year asks me what changes I've made to the car since the last tech. IRS cars include most corvettes and we have our share of bad a$$ bowtie vette's running 10.00's. Some tracks are probably more picky, or clueless, or just don't really check much until they have a bad accident. At the SEZ that I went to tech was basically non-existant due to my current Alb. National NHRA tech inspection sticker on the rollbar next to the driver seat.

 

IMHO and from experience most any car in the 9's is running a solid rear axel. Fundamentally it's probably a good idea although not completely necessary.

[badassbowtie]

Is the tech at different tracks that inconsistant? I had no idea. I dont think my car will be faster that 10.00 but dont want to get turned away for not having some safety issue. Thanks for the input.

[SilentNight1647]

Tech is very inconsistent between different tracks, up north they know me and the cars I bring up there pretty well and don't really go over the car with a fine toothed comb. Down south the ZX doesn't even get looked at but the Nova is up in the air making sure all the pieces are there and it's not rusted out. So it really depends on the track.

[jnjdragracing]

I agree it all depends on the track, We have been to bought NHRA and IHRA. To me NHRA tracks are more concerned with the car.

 

The most vigorous tech we had to go through was at Bristol TN when we entered Pinks all Out. They are all concerned with Safety which is a must.

 

We met with a NHRA tech guy yesterday Saturday to get our New 10 point cage certified to a 8.50 and it passed, what he was concerned with the most was the thickness of the tubing, he just glanced at the welding and the 6x6 plates. He did offer us some good info after looking at the hole car.

 

1) the seat belt harness, how to properly mount it especially the crouch belt ( needs to be anchored right under your butt, not in front). The rest need to be mounted with buckle facing the belt. If you drill and bolt thought the back tubing you need to insert and weld a tube through it.

2) he looked at our IRS suspension and said we needed to shield the plastic fuel cell, on the back side and sides in case we through a shaft no debrie would crack the plastic cell.

3) We have a flywheel shield, but he said we also need a trans housing shield. ( we have it just not on yet ).

4) long rear wheel studs. We had one that was short and it needed to be long.

5) Window net need to be secured inside the roll bar, not outside like most people do it. Need to have welded loop bar fasteners that the window net bar slides through.

6) Sealed battery boxes even if you are running optima batt. In case of explosion it will contain itself.

7) Fuel cell bulk head to cover the opening of the fuel cell, Needs to be separated from the inside of the car. If it was a trunk car then it was not needed. We already had that, and also the plastic fuel cell needs to be grounded with a ground strap.

8) and of course they do not like any rubber fuel line ( we have all braid and alum. fuel line ).

 

You will need a fire jacket, an approved helmet is a must. We opted to get it all Jacket, pants, neck collar, gloves.

 

Hope this info helps you out.

 

If you have a roll bar I would not worry to much at most tracks, but the above in mind.

 

John

[dr_hunt]

It's sad that tracks can be that different, the onus is on the owner, be safe! From what I've seen, when a track has an accident, whatever seemed to have caused the accident becomes paramount in the tech inspection.

[badassbowtie]

Thanks for the info, I have raced before so I know most of the other rules. I have never raced an independent rear suspension car. Do you have a pic of you fuel cell set up jnjdragracing? I am just getting done with putting a plastic fuel cell in where the spare tire used to be. Did they specify how thick of a shield for the fuel cell?

[jnjdragracing]

I don't have one right off. Our tank is in the spare tire hole. Right now it sits flush with the top of the spare tire hole, meaning the opening where you pour fuel is even / flush. We plan on raising it up some to help with the flow of fuel. No he did not say, we will probably use 22 gauge steel to make it.

 

Jerry is suppose to do that and we have to relocate our 2 batteries due to the new rollbar. I will take photos as we progress on it.

 

John

 

Thanks for the info, I have raced before so I know most of the other rules. I have never raced an independent rear suspension car. Do you have a pic of you fuel cell set up jnjdragracing? I am just getting done with putting a plastic fuel cell in where the spare tire used to be. Did they specify how thick of a shield for the fuel cell?

[jnjdragracing]

Thanks for the info, I have raced before so I know most of the other rules. I have never raced an independent rear suspension car. Do you have a pic of you fuel cell set up jnjdragracing? I am just getting done with putting a plastic fuel cell in where the spare tire used to be. Did they specify how thick of a shield for the fuel cell?

If you go to the members photo gallery there is a picture of the rearend and fuel cell. A friend of mine has made loops for the rear cv/haftshaft containment I will check with him and see if I can post a picture of how he made them (Get his permission), His NHRA Tech said the loops would pass NHRA guide lines. Jerry

[Pyro]

not all IRS setups are the same. for example. If an old vette breaks a 1/2 shaft, it will lose rear wheel control. If a Z breaks a 1/2 shaft or even an axle, the wheel will stay attached to the A-frame. Just makes a bunch of noise from the 1/2 shaft knocking around.

[Z-Gad]

I haven't had any tech issues in the 3 tracks I have run on regarding the IRS...

[Michael]

Rumor is that to most track safety inspectors, all IRS systems are the same. They do not distinguish between C4/Jag setup, Chapman struts (S30Z) or double-wishbone. Some may require safety loops around the halfshafts.

 

The fuel cell issue is another one for the rumor mill. Some inspectors may require building a firewall separating the hatch area from the cabin. In my car the fuel cell is bolted to tabs welded to the spare tire recess; it is literally sitting in the hatch area, with the stock floor untouched. That takes care of the underbody debris problem and isolation from the exhaust. Between the rear strut towers there’s a sheet metal firewall, against which the fuel cell is pushed. But I still need to build a wall going all the way up to the hatch lid hinge area - and if nitpicky, to also build partitions outboard of the strut towers, going to the quarter panels. But that is bordering on silly. If I do build the aforementioned wall, I will remove the hatch itself, and will try to build a cover for the fuel cell - a sort of Pantera hatch.

[badassbowtie]

So I guess the consensus is that I find out what I need to change when I go race.

[660Z]

Well my timing sucks!!! When I tore apart my car for the cage and frontend metal work, it was 11.99 and quicker needed a cage. Then they changed it to 11.45 and quicker. I could have played longer!

 

NOW, everybody is passing tech with IRS rears. I could have been ready last year if I didn`t decide to switch to solid. I switched because at the time everyone was saying IRS won`t pass tech and at the time even the Corvette IRS was time limited.

 

Do you know how much money and time I could have saved if I didn`t want to be hassled by tech. Strange 33 spline axles, full spool and C-clip eliminators aren`t cheap you know!!

 

You guys suck with your pushing the rules attitude and daring the tech guys to say something so you can start an argument mentality.......

 

I`m just giving you guys a hard time. Though my timing does suck and could have saved me time and money.

 

Reading the posts it does seem the southern tracks are more relaxed on the rules then the northern tracks. Here at Cecil County I`ve noticed rules are really being enforced lately compared to the last couple of years. Helmet and seat belt date/cerification on test & tune to name a few.

[Six_Shooter]

660Z; Do you have any information (like pics) of your solid axle swap? I'm pretty sure I know how I'm going to do my swap (basically a back-half), but would like to see what others have done or are going to do.

[660Z]

I don`t have any pics of the rear setup yet. The rear has to come back out for gears and bracket reinforcement. At the time I rushed it after getting the rear setup so I can move it and move onto other things to stay interested. I`ll take pics then when things look better.

 

What I did that`s a little different then others. Is instead of cutting the rear down I compensated with wheel backspace. Side note: having an uncut rear also makes it easier ordering axles, just tell them the year and make it came out of. They have all the mesurments for it.

 

The Nova rear is 60" and with a backspace of 7.5 on 10" rims, which put me back to the factory track width. Of course having fender flares helps also.

 

The suspension, i just followed MikeKz`s lead using the Jegsters S/S bars and S&W coil over shocks, but instead of using the shocks in your typical spot behind the rear, I installed them on top and used the strut towers.

 

Mark

[badjuju]

I think PIR (formerly SIR) up here in Washington makes you have a helmet under 12, a cageroll bar under 11, or 13/12 if you have t tops or something... Past that I've heard they don't really care

[badassbowtie]

I live in Oregon but have not raced here. Thats interesting that the west coast seems to be really lax on the tech inspections.

[Guest Gr8White]

I've found that not only the tracks are inconsistent in how they treat IRS cars, but the tech inspectors themselves are inconsistent. If you have multiple tech inspectors alternating track duties, what gets their attention seems to vary, unfortunately.

 

I have noticed that having marginal or minimal safety equipment for the times the car is capable of seems to be where the officials begin "digging". If you have the harness (still in date), proper rollbar or cage, fire jacket, extinguisher, etc.- they tend to investigate the car less. Have everything ready to inspect, no junk lying around inside the car and don't make it hard for the tech official to do his job. If you come to tech unorganized "Uh, I dunno, I think I have my fire jacket with me, lemme look"...they get annoyed and start looking for reasons to boot you.

 

I know this may sound like a common sense thing, but if it's a track you plan on running at more than once, don't be stupid with the car. If it gets out of the groove and gets squirrely, get out of it and try again. If you break, get over to the side ASAP and don't oil down the track! They are a lot less likely to boot you for breaking the IRS or whatever elseif you consider others when breaking and don't look like a dip$hit.. If the officials tell you not to run an 11.99, don't push it with the one warning for the 11.96 and then loow 12's the rest of the night......These guys do remember cars and will make a mental note of somebody playing games or continually bending/breaking the rules....JMHO....

[badassbowtie]

That makes sense, gr8white, where do you race at? I wont be racing this summer, I will be happy to drive the car and start getting the kinks out. I am just trying to plan ahead and build the car to be legal. Has anyone done any top speed racing? How tight is the tech there? I would imagine it would be much more strict. I have visited the site for the salt flat racing, and found the rules very general. I didn't see any cage certifications.