7 replies to this topic

[Foleyracing3]

Hello all,


I was running an omp rspt seat but being 6’3 I couldn’t get the seat back far enough to be comfortable. So I purchased a Kirkey 71 series seat wich seems to be much better.. I will be mounting the seat to the floor and had a question regarding the sub belts being pinched under the seat. Is this something to be worried about ? Or a normal factor for floor mounted seats .




Thank you for your time !

[EMatoy]

I put the belts on the top side of the seat (I sit on them) and bolt down thru the seat and thru the floor. None of the holes in the seats made for a belt to pass thru are far enough back in the seat to be useful for me.

[tjohn67]

I have lap belts that are designed to hook to the same anchors as the lap belts and then you sit on them.  Works really well 

[callumhay]

Going from memory ....mounting a Kirkey seat and having the same concern with the sub belts. What I did was purchase belts with eyelets for bolts in the sub belts, not snap on. As you probably know, snap on requires a ring mount and there might not be enough room under the seat for that. The eyelets take a bolt directly and are slightly less than 1/2 as high as a ring mount. This gave enough clearance so that the belts or eyelets did not bind under the seat. I used Jim Drago's seat mounts which are perfect for dialing in fine adjustments of the seat. Also I found playing with the layback of the seat to about 20 degrees helped by tilting the front of the seat up, thereby giving more clearance.
Couple of other tips... I mounted a flat aluminum plate to the floor to allow a nice flush surface to work on...also was great for planning holes by using a sharpie. If you are tall you may have already used the tall driver floor pan so that may be flat enough. I did have to cut the mounting brackets at the rear I think to allow clearance for the lap belts. The belts I used were Safecraft and they give you the option of buying the sub belts with eyelets. Use the FIA diagram online to determine the proper placement both front to back and side to side and it is well worth it doing a good job with that.

Good luck with it

Cal

[Bench Racer]

This SCCA SMCS rule was added a couple years ago for larger drivers.

 

7. Driver/Passenger Compartment - Trunk
a. The driver’s seat shall be replaced with a one-piece bucket-type race seat. All seat mountings shall
be reinforced. Factory seat tracks/brackets may be modified, reinforced, and/or removed to facilitate replacement mountings provided they perform no other function. The passenger seat must
be removed. The transmission tunnel may be modified for the purpose of installing a competition
driver seat. The driver’s side floor pan may be modified to accommodate larger/taller drivers. All
modifications shall be contained between the transmission tunnel, driver’s side rocker, rear bulkhead and no more than 24” forward of the rear bulkhead. The modification shall not extend below
the factory floor stiffener/frame rail. The steel used in the modification shall be no thinner than
.058”. All modifications shall be welded in place. This modification shall serve no other purpose
other than seating position.

[Foleyracing3]

This SCCA SMCS rule was added a couple years ago for larger drivers.
 
7. Driver/Passenger Compartment - Trunk
a. The driver’s seat shall be replaced with a one-piece bucket-type race seat. All seat mountings shall
be reinforced. Factory seat tracks/brackets may be modified, reinforced, and/or removed to facilitate replacement mountings provided they perform no other function. The passenger seat must
be removed. The transmission tunnel may be modified for the purpose of installing a competition
driver seat. The driver’s side floor pan may be modified to accommodate larger/taller drivers. All
modifications shall be contained between the transmission tunnel, driver’s side rocker, rear bulkhead and no more than 24” forward of the rear bulkhead. The modification shall not extend below
the factory floor stiffener/frame rail. The steel used in the modification shall be no thinner than
.058”. All modifications shall be welded in place. This modification shall serve no other purpose
other than seating position.

I already have a drop floor installed and it’s great ! I have the sub belts mounted behind the seat to eyelets . My main concern is the webbing being pinched underneath the seat when installed

[Steve Scheifler]

Doesn’t sound like the typical recommended mounting location, though I’m not sure it’s critical. Similar to Cal’s description, the seat bottom already slopes up from thr floor forward, and that combined with a little extra tilt-back we prefer makes it possible to bolt the sub-belt eye to the floor at the recommended distance behind the hole in the seat. We have sometimes drilled an extra hole in the seat bottom so the head of the belt mount bolt can come through it and be essentially flush with seat bottom.

[callumhay]

I already have a drop floor installed and it’s great ! I have the sub belts mounted behind the seat to eyelets . My main concern is the webbing being pinched underneath the seat when installed

If you are going to use this method, I think you will find enough clearance with the seat mounts (for sure the East Street ones). I think you will only need 1/4 inch or less.

 

My first car came with this method of mounting the Sub Belts. As Steve says, it may not be the best way to mount them. It wasn't until I built my own car and looked at the FIA mounting recommendations that I found out that mounting the sub belt attachment behind the driver is not recommended. The recommended way is beneath the driver, just behind the slot opening. They have recommendations as to the angle of attachment side to side and front to back. This presumably is to maximise the restraining effect of stopping the driver from slipping down or "submarining" . I am not an engineer and do not know if there are any negatives to the mounting points for the subs behind the seats. I do know that when it comes to safety equipment that any deviation away from recommendations incurs risk. I know this is not the question from the OP but it does bear some thinking about for anyone who is mounting belts in their car and what the recommended procedure is.