Racing Harnesses

[buzzboy3002]

Me and my dad are looking to install racing harnesses in our stock 1973 240z. We do not want to have to drill any holes or install any roll cages. Is this possible?? It looks like the cargo tie downs in the back could be used but I have no idea. Thanks in advance.

[Ron Carter]

Good question.

The lap belts won't be a problem as the factory bolt that holds the OEM belts can be used. The real problem, or challenge, is the shoulder belts as they need to be installed higher than the cargo tie downs. In a hard accident the belts will try to collapes down and can break your back or slip off your shoulders rendering them useless. I would suggest that you mount to the top of the rear strut tower and use a belt that will work effectively mounting to that single location.

A roll bar mount is a much better solution, but if you are not going to install a roll bar then this is your best bet.

Are you using the factory seats?

[buzzboy3002]

We are leaning more towards the factory seats, but we are considering racing seats. The problem is would need a seat that fits both of us. Can you recommend any seats and any good belts for our situation?

[Walter Moore]

Several years ago I bought a set of "DAD" brand racing seats on Ebay and they came with harnesses. On this particular set, the upper belts mount to the shoulder belt mounting bolt in the back. On a 240Z the shoulder belt mounting bolt is back by the hatch. My harness has a single webbed main strap that connects to two separate shoulder straps that then go through openings in the seat.

There are a several issues with using a racing harness in a street car.

1. Without the racing seats the belts would have to wrap around the sides of the stock seats, which would tend to cause them to slip off of your shoulders. A standard shoulder belt avoids this because it crosses across your entire body to the latch on the other side.

2. I have been told (on this site in fact...) that without a roll cage in the car they could actually increase the danger to the occupants because they will hold you upright in a roll-over while the roof collapses on you. (I am somewhat dubious of the concern since if the roof crushes that far you would be in serious trouble in any event, but thought I should pass it along.)

3. They are a royal pain to deal with if more than one person intendeds to drive or ride in the car. It takes several minutes to adjust them when someone different uses the seat. I suspect that this is the underlying reason that governments never required four point harnesses in the first place. They really are more comfortable than a three point seat belt when properly adjusted, but it is a time consuming process to get them setup.

To be honest, I am strongly considering replacing them with the three point seat belt that Motorsport Auto is selling, just because I am tired of having to adjust the passenger side harness every time that certain family members ride with me in the car. Apparently in my immediate family only males are capable of adjusting belts.....

(No offense intended to any female who is not related to me!)

[Ron Carter]

What do you intend to do with your car and what differences are we talking about in size for both drivers?

Seats, racing seats come in many different styles and shapes. There are seats that have good support and true racing seats.

Help me help you.

R

[buzzboy3002]

My dad and I are similar builds, both tall and lanky, I am 6'2, he is officially 6' 3", but probably stands around 6' 1", we both weigh around 160, I am not sure how close our shoulders and hips are in measurements, but I can find out if necessary. My dad would also like to be able to return the car to stock conditions and would like it close to stock conditions (i.e. no bolt on engine upgrades but we have discussed seats and belts but neither of us know very much about them.)

I like to be held in the seat very tight, and to not slide around at all, while my dad likes to be held a little looser, if not completely loose. The car is mostly for fun and will be driven sportily and used for me to touch up my manual shifting and heel- technique. There is a very good chance we will take it to autocrosses, and there is a slight chance for a track day here and there.

[doradox]

Another thing to consider is if you do it make sure you use a 5 pt system. With just 4 pts. the shoulder straps will pull the lap belt up on your body during a crash unless you have really cinched down on the lap belt (uncomfortably so). This puts the lap belt across the soft stomach area instead of across the hard structure of the hips. Of course with the stock seats the 5th belt can't be mounted to work properly unless you cut a hole in the seat.

Steve

[Ron Carter]

Okay, now we are getting somewhere.

I think you are going to have to compromise with your desires and your Dads as you both have different requirments for comfort and support. For your requirements the seatbelts will hold you really firmly, look to that instead of your seat bolster to hold you in place. You will need to look at seats that fall into the catagory of a sporty seat that is comfortable for both of you. You will want a seat that has a low, thin bottom cushion with a mild side bolster as you are both tall and many GT style seats are pretty thick on the bottom cushion.

In my street 240 I had design 2000 seats (made by Recaro) that fit the bill. A good cofortable seat, it used the stock mounting locations and because it had an adjustable head rest, the 4 point harnesses worked well. The shoulder belts that I had were 2 straps that were sewn into one and attached as I mentioned above the lap belts were attached to the factory locations.

This solution gave great support for spirited daily driving, like auto x and running around on the street. It is not a solution for a serious racing application. However at that point you are going to need to modify your car beyond a point where it can easily be put back to stock.

I agree that a anti submarine belt is a good idea in a full race application, but it would require drilling a hole in the floor of your car and for daily use it would be quickly abandon.

I would suggest that a 4 point latch-link or cam lock system is the way to go. A moderate racing seat that you both find comfortable with a location for shoulder belts and you will be all set. This will fit the bill for auto-x and an occasional track day.

If you decide to get more involved, and put together a dedicated car for track and autocross, there are other safety related suggestions I would make.

[IBZINYA]

I purchased two 5 point harnesses from Safe-Racer made by G-Force. They have cam locks and bolt in hardware. They are 3 inch thick through there entire length and I secured them to the original seat belt mounting points, using the original mount bolts. Check the pics and see that I mounted the shoulder belts to the rear strut mounts, again using the original nuts and washers. I then trimed the tower covers just enough to clear the buckles and snaped them back on.

Hope it helps.

[buzzboy3002]

Would more agressive seats w/ holes in them for harnesses work better than the design 2000 seats? Or would they be too tight of a fit for my dad, or do you have to install different rails to mount them?

[buzzboy3002]

Wow, I think that would work perfectly. Do those belts come in 2 inches? and do they have 4 pt. versions of the same thing?

p.s. Thanks for the pics, they are very helpful.

[buzzboy3002]

I purchased two 5 point harnesses from Safe-Racer made by G-Force. They have cam locks and bolt in hardware. They are 3 inch thick through there entire length and I secured them to the original seat belt mounting points, using the original mount bolts. Check the pics and see that I mounted the shoulder belts to the rear strut mounts, again using the original nuts and washers. I then trimed the tower covers just enough to clear the buckles and snaped them back on.

Hope it helps.

What do the bottom two belts attach to? I couldn't see in the picture or find a place in the car.