1 (edited by Evil Genius 2010-06-19 12:52 PM)

Topic: Common Tech Failures. UPDATED W/PIX

I figured I'd post some of the most common tech failures we've seen, nationwide.  Please read the below information and look at your car, let's get through tech quickly....

1.  360 degree welds on the cage.   Often on the main hoop to halo or down bars and the door bars to the main hoop, two very difficult places to get a complete weld.  One car at Phoenix had only tack welds on the door bars.   We've also seen some really poor welds: cold, lumpy and weak.  You have to be a good welder to build a cage correctly.  A cage built with a 110 V flux core welder is likely to fail.     

1a. Please read the roll cage rules- We are seeing a bunch of cars without backstays and main hoop diagonals.  At Pointless there was quite a few teams struggling to get their cages fixed before the race started.  Also, two of the recent rollovers were cages that were found lacking  and were fixed the night before the race.  Re-read the cage rules and get it right.  Your backstays should be as close as possible to 45 degrees and have NO BENDS..   

1b.  Mandrel Bends. Some of the cages we've seen have crush bends. Not acceptable!  If your cage is bent on an exhaust bender it is going to fail..  No question.   

2.  Poorly installed harnesses.    Mostly the belts aren't wrapped correctly, look at a diagram, when finished the loose end of the belt should be pointed away from the driver and only one bar of the 3 bar clip should be visible, again,  look at a diagram online or the one that comes with your harness set.   On clip-in belts, you need to install a locking cotter-pin or safety wire.  All bolts/eyebolts must have strong mounting points, either the stock,welded in and reinforced seatbelt mounts  or backed up with washers as per the rules.   Lap belts must be at the right angle to restrain the driver, we've seen quite a few belts that were mounted too far forward to do any good, the belts must lay on the drivers hip-bones and pull both down and back to be effective.   Same with sub-belts, the belt must pull down and back, we will fail a sub-belt that runs over the front of the bottom seat cushion and back to the lap belts.    All parts of the harness should be away from sharp protrusions that will fray the belt and cannot be mounted so that the webbing of the harness is clamped between the metal of the car and the belt bracket, that will also cause fraying.    If you have HANS-specific belts then everybody on your team MUST use a HANS, these belts are not safe without the use of a HANS.  The BEST way to install shoulder harnesses it to wrap them around a harness bar at the right height. You want to sail through tech?  Have wrapped shoulder harnesses at the right height with the belts threaded through the clip correctly. Just do it, or we are likely to make you fix it at the track.     

3. Poorly installed seats. Loose, sloppy seats will fail tech.   The seat must not be able to fail in a rear-end impact.  That means that there has to be something structural within 6" of the back of the seat, that includes your shortest driver.  A back brace is highly recommended.  This rule also includes in-date FIA seats, there is no difference in the rules by type of seat, all must not be able to fail rearward.

4.  Disconnect Switch.  The switch must cut off all power to the engine, that usually means that the alternator circuit has to be cut as well as battery power.  The switch also has to be reachable and marked.

5. Electrical clean up.  Most of you have managed to cover the + terminal on your battery, but not on the back of your disconnect switch or elsewhere there is 12 volt power.   If I see an uncovered terminal or bare wire, I will make you cover it.   

6.  Loose stuff.  Zip-ties are you friends, get everything tied down.  This falls under the de-scuzzification part of the rules.   

7.  Fire extinguisher, geez, you'd think that the rules are written in Sanskrit.   Metal brackets that are through-bolted, done.  Why do we still see so many plastic brackets held on with one screw?   

8. Windshields:  We've seen a bunch of totally spider-webbed broken windshields lately. We failed them and the teams had to scramble for a windshield Friday night.  A few small cracks/ chips are ok, beyond that, get it fixed. 

9.  Oil leaks- we cannot let the track get oiled down and a car that leaves a trail of oil through tech is going to be told to fix it.

10. roll cage padding.  There must be padding any where the driver can contact the cage while strapped into the seat. Add padding!

11.   Fuel cells.  If the cell is not an FIA certified rubber bladder cell (Fuel Safe or ATL) then it must have a sealed metal barrier between it and the driver, even if it is in a metal can.  NO EXCEPTIONS!      This means most cells from Jazz, RCI, Summit, Etc.   They all need a metal bulk head between the cell and the driver.   A fuel cell install is always judged by its quality of install and is looked at by the race manager, The bar is high, do a good job.     

These are what I've seen most often: there are, of course, many others, read the rules and ask questions.

-John

Here's are some photos of some of the common failures we see--in no particular order:

http://farm5.static.flickr.com/4075/4742503921_0898a48874_b.jpg
http://farm5.static.flickr.com/4121/4743141264_de85630772_b.jpg
http://farm5.static.flickr.com/4076/4742503285_54821efc4d_b.jpg
Scary-looking cage spreader plates are REALLY common. Make sure they are appropriately sized, attached with good welds, and affixed to a part of the car that is structurally sound. Air space, missing or crappy welds, and undersized plates will ALWAYS catch the eye of the tech inspector.



http://farm5.static.flickr.com/4143/4742502215_12de2b8f10_b.jpgBent rear stays are really common--they significantly compromise cage integrity and result in an essentially automatic tech failure. Make sure your cage builder knows to run them in a straight line.



http://farm5.static.flickr.com/4121/4742504875_0bc79c32e4_b.jpg
The rear stays of can't terminate in the strut bar, as they do here. They need to extend to appropriate spreader plates in the floor or frame.



http://farm5.static.flickr.com/4117/4742852841_0f0967765b_b.jpgThe diagonal does not continue across the entire plane of the main hoop--it is required to.



http://farm5.static.flickr.com/4116/4743488328_75329f1661_b.jpgCage positioned too low in car--you don't want your head poking up over the top of it.



http://farm5.static.flickr.com/4081/4742502991_b2cec33b8f_b.jpghttp://farm5.static.flickr.com/4101/4743139966_bfdda9a3dd_b.jpgCrimped bends are a no-no. Basically, if you can see any deformation in the bend, that won't fly.



http://farm5.static.flickr.com/4101/4742504099_d695bab202_b.jpgThe rear stays should be as close to 45 degrees as possible--too steep or too shallow (seen here) puts you at risk of failure.



http://farm5.static.flickr.com/4095/4743142966_f788d92841_b.jpg
This one is actually in somewhat of a gray area--what the cage builder SHOULD have done here is run the rear stays to the shock towers with the appropriate mounting plates. Running the rear stays toward the center is a much less sturdy layout--and puts you at risk of failing tech.



http://farm5.static.flickr.com/4135/4743142488_cb28d7ef8b_b.jpg
http://farm5.static.flickr.com/4096/4742504497_104dc2b089_b.jpg
We get a lot of questions about what constitutes an unacceptable windshield crack--it's hard to say, but if you have to ask, you're probably screwed. These two didn't fly.



http://farm5.static.flickr.com/4101/4743142134_8bde7feb99_b.jpg
FIA-certified fuel cells can be used without a metal firewall between it and the cockpit. That means we'll be looking for the FIA stamp--this cell didn't have one, so it needs a firewall.



http://farm5.static.flickr.com/4081/4743140938_d4d5924315_b.jpgSeat belts must be mounted between zero degrees and 15 degrees below the seat entry point. Anything that comes downward like these do will fail.



http://farm5.static.flickr.com/4079/4742502805_37f71f80a4_b.jpg

http://farm5.static.flickr.com/4078/4742502603_9fc3f1cdc2_b.jpgIncorrect lap/sub belt placement--the anchor points need to pull back and downward on the driver's waist--so the lap/sub belts must be anchored in spots that pull the driver TOWARD the seatback.



http://farm5.static.flickr.com/4095/4743143202_056a94ce6e_b.jpg
Anti-submarine belt coming over the top of the seat squab is pretty much an automatic failure. The anti-sub belt should be anchored at a point behind the center of the driver.



http://farm5.static.flickr.com/4095/4742502447_7078cc36db_b.jpgHooptie-ass fire extinguisher mount. The rules specify a bolted-in metal quick-release mount--this ain't it.

Gosh, my business card says 'Tech Tyrant'

Re: Common Tech Failures. UPDATED W/PIX

And let me add one item:

Shoulder belts attaching to the cross brace at the wrong height...


When you get your cage built make sure that the angle to the belts is correct.  0 to 15 degrees, or you will have to have emergency welding done.

El Capitan de los Bastardos De Lemons
1993 Linco Mark Ate
1957 Renault Dauphine
Driver with LemonSpeed's V6 Mustang

Re: Common Tech Failures. UPDATED W/PIX

Also shoulder belts secured really far behind the driver like on the rear self, they should be closer to the back of the seat, the harness bar should be within 6" of the seat back. belts are stong but in a hard hit they will stretch if there is extra unneeded length.

4 (edited by caseypeeps 2010-01-31 09:26 PM)

Re: Common Tech Failures. UPDATED W/PIX

Submarine belts, we had cut a hole in our seat at tech to make the angle meet their requirment. They also told us they want the shoulder belts at a 15 degree angle from where they attach to the cage up to the seat. very good advice from evil genius, you don't want to rush to fix anything that has to due with saftey.

Team E=MCHAMMERD

Re: Common Tech Failures. UPDATED W/PIX

for those racing at "Sears Pointless"....its a GREAT idea to pre-tech BEFORE the race.....sure you think its just fine and dandy...but have the tech inspectors who are the same guys who tech during the race take a look at your car....plus its an excuse to hang out, drink beer and eat greasy BBQ before the race!!!

Richard Doty
1984 Porsche 928 "Estate"
Porsche- "there is A substitute" Racing
Dirt Poorsche Racing #2

Re: Common Tech Failures. UPDATED W/PIX

Evil Genius wrote:

4.  Disconnect Switch.  The switch must cut off all power to the engine, that usually means that the alternator circuit has to be cut as well as battery power.  The switch also has to be reachable and marked.

Might want to clarify "reachable." I assume that you mean reachable by safety workers? Seems like the driver will often not be able to reach the switch in its required/recommended hood or cowl location.

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.

Re: Common Tech Failures. UPDATED W/PIX

Mulry wrote:
Evil Genius wrote:

4.  Disconnect Switch.  The switch must cut off all power to the engine, that usually means that the alternator circuit has to be cut as well as battery power.  The switch also has to be reachable and marked.

Might want to clarify "reachable." I assume that you mean reachable by safety workers? Seems like the driver will often not be able to reach the switch in its required/recommended hood or cowl location.

I did not mention anything about this before either.

While our switch is reachable from outside and from the driver's seat, I do not recall it being "required" to me accessible to the driver.

Many cars have their kill switches mounted on the cowl.

I prefer it to be within reach of the driver.  It's safer and it puts the safety workers within arms reach as well.

Troy

#35 LRE
1973 Datsun 240Z

Re: Common Tech Failures. UPDATED W/PIX

Mulry wrote:
Evil Genius wrote:

4.  Disconnect Switch.  The switch must cut off all power to the engine, that usually means that the alternator circuit has to be cut as well as battery power.  The switch also has to be reachable and marked.

Might want to clarify "reachable." I assume that you mean reachable by safety workers? Seems like the driver will often not be able to reach the switch in its required/recommended hood or cowl location.

That is correct, the safety workers have to be able to get to it....  Maybe we should have put the switch for the V8olvo through the floor.......

Gosh, my business card says 'Tech Tyrant'

Re: Common Tech Failures. UPDATED W/PIX

can someone clarify the anti sub belt mounting?

Team Lost in the Dark
Winner " I got screwed" and "Jay's dream car"
2012 Gulf region champs

Re: Common Tech Failures. UPDATED W/PIX

Baron wrote:

can someone clarify the anti sub belt mounting?

The crotch belt has to hold the lap and shoulder belts in place and prevent the driver from going under them.  To do that, it needs to be tight when the rest of the belts are tightened.  The only way to do this is to have it come up through the bottom of the seat near, well..., your crotch and not up the front of the seat.  If it comes up the front - it will allow the driver to sink ~1' before catching them.  In the process breaking thier lower back.

--Rob Leone Schumacher Taxi Service
We won the IOE at Southern Discomfort.
We got screwed at The Real Hoopties of New Jersey  and we took cars down with us.
We got the curse at Capitol Offense but they wouldn't let us destroy the car.

Re: Common Tech Failures. UPDATED W/PIX

We had an odd breakdown at the Thunderhill race.  One of our members hit the brakes hard at the corners.  They were smoking when he came in.  The master cylinder gave out shortly after that.  That put the car in the pits for 4.5 hours.  Turns out it is an odd master and we had to rob one from a wrecking yard. 

We also had the Master electric shut off switch short out.   This cut the alternator off and the battery died. 

I could list a multitude of other issues but they moslty have to do with picking the wrong car to start with.   Keep it simple! 


Dudes

Re: Common Tech Failures. UPDATED W/PIX

Is there a special tech inspection for Toyota Gas pedal assemblies?

William
Team SOB

Re: Common Tech Failures. UPDATED W/PIX

zigm wrote:

Is there a special tech inspection for Toyota Gas pedal assemblies?

zing!

it's odd that excessive acceleration is Toyota's big problem now, when acceleration isn't exactly something they were known for before.

mike - Schumacher Taxi Service
12+-time loser
"Winner" - We Got Screwed, NJMP '11

Re: Common Tech Failures. UPDATED W/PIX

Toyota with an Audi 5000 theme???

Official photographer/Team Police Brutality|Speedycop & the Gang
Lackey-mechanic-whatever/NSF Racing
Sycophant/Judge Phil, Jay Lamm, Kim Harmon
Galaxie Driver/not Parnelli Jones

Re: Common Tech Failures. UPDATED W/PIX

heheheh... a new penalty for over-aggressive driving.

The Toyota Recall

Remove your gas pedal assembly for the Judges to inspect for defects.  Additional washers may be required to reinstall.

William
Team SOB

Re: Common Tech Failures. UPDATED W/PIX

Buzz Killington wrote:
zigm wrote:

Is there a special tech inspection for Toyota Gas pedal assemblies?

zing!

it's odd that excessive acceleration is Toyota's big problem now, when acceleration isn't exactly something they were known for before.

Maybe that's our problem: we need to install factory floor mats!

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.

Re: Common Tech Failures. UPDATED W/PIX

zigm wrote:

heheheh... a new penalty for over-aggressive driving.

The Toyota Recall

Remove your gas pedal assembly for the Judges to inspect for defects.  Additional washers may be required to reinstall.

I endorse this penalty and look forward to its implementation.

Aaron

1999 Astro (Green the Daily Driver) - 2WD, 4.3L, 3.23, 200k+ miles, FE2 steering
1997 Astro (Grumpy the $250 Rally Van) - AWD, 4.3L, 3.42, 330k+ miles on the orig eng and trans, $30 eBay fuel pump

Re: Common Tech Failures. UPDATED W/PIX

RobL wrote:

The crotch belt has to hold the lap and shoulder belts in place and prevent the driver from going under them.

Yeah they kind of misnamed the "sub belt".  It's real purpose is to keep the lap belts in the correct position over the hips.  Disconnect the sub belt and pull the shoulder straps tight and you'll see what I mean.  The lap belts will end up over the spleen instead of over the hips.

Captain
Team Super Westerfield Bros.
'93 Acura Integra - No VTEC Yo!

Re: Common Tech Failures. UPDATED W/PIX

How do the tech people judge welds?  I have seen some welds that looked like crap but passed tech, because they still had good penetration.

Namco Racing #48 Miata

Re: Common Tech Failures. UPDATED W/PIX

zigm wrote:

heheheh... a new penalty for over-aggressive driving.

The Toyota Recall

Remove your gas pedal assembly for the Judges to inspect for defects.  Additional washers may be required to reinstall.

That happened to us, although unintentionally. The gas pedal became disconnected from the linkage and we had to get towed in!

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.

Re: Common Tech Failures. UPDATED W/PIX

rharris19 wrote:

How do the tech people judge welds?  I have seen some welds that looked like crap but passed tech, because they still had good penetration.

A crappy-looking weld is not necessarily a bad weld, but a pretty weld is almost always a good weld, since obviously the guy doing the welding knew what he was doing.  So, a pretty weld is more likely to pass tech, I would think.

If it ain't broken, fix it 'til it is.

Re: Common Tech Failures. UPDATED W/PIX

I've been asked to bump this to make it easier to see....

Gosh, my business card says 'Tech Tyrant'

Re: Common Tech Failures. UPDATED W/PIX

Don't forget the tow hooks are required now for 2010

24 (edited by Tajracing45 2010-02-13 04:59 AM)

Re: Common Tech Failures. UPDATED W/PIX

5. Electrical clean up.  Most of you have managed to cover the + terminal on your battery, but not on the back of your disconnect switch or elsewhere there is 12 volt power.   If I see an uncovered terminal or bare wire, I will make you cover it.   

Interesting....  never been popped for having the exposed + behind the disconnect.  With the four terminal switch, the area behind our switch is pretty tight.  How does everybody cover their + terminals?  Electrical tape?  Zip tie a cap from a majic marker or something similiar to it?  I like to be legal you know...   wink

We are the people your parents warned you about.

Re: Common Tech Failures. UPDATED W/PIX

I used electrical tape. But now I'm thinking using a paint spray can lid if it's the right diameter, to cover the bottom. Cut some holes on the sides for the wires to pass and zip-tie it to the switch.