jonD6B 0 Posted January 31, 2006 I am in the process of fitting a 4 point harness. I have fitted one eye bolt by the drivers door into the exsisting seat belt hole. I have fitted one eye bolt centrally behind the drivers seat into an exsisting hole to which I have attached both rear harness restraints. I plan to weld an O.M.P. reinforcing plate to the top of the transmition tunnel inside the car to take the final eyebolt for the side harness. Is this how most people do it or am I going in completely the wrong direction? Share this post Link to post Share on other sites
hengti 2 Posted January 31, 2006 The OMP plate sounds like a good idea Like yours, my 3 point is attached using the existing bolt holes for the rail down by the door bottom and the rear seat belt anchorage in the seat base I've had to attach the left side lap belt eye bolt to the buckle mounting point which is actually on the seat frame - not the best, as, if the seat breaks during a smash, I've had it. 'tis the standard fixture point though I'd feel happier using the plate you've found How are you getting both latches on the rear belts onto the one eye bolt in the back though? I originally bought a 4point, but the clips wouldn't go on safely - they need to be free and shouldn't be 'wedged against each other' Share this post Link to post Share on other sites
DrSeuss 0 Posted January 31, 2006 you want as shallow an angle possible with the rear belts. Any more then about 15 degree's and you risk being crushed by the harness during an accident. You should also never use harnesses without a roll cage. Share this post Link to post Share on other sites
jonD6B 0 Posted January 31, 2006 The OMP plate sounds like a good idea Like yours, my 3 point is attached using the existing bolt holes for the rail down by the door bottom and the rear seat belt anchorage in the seat base I've had to attach the left side lap belt eye bolt to the buckle mounting point which is actually on the seat frame - not the best, as, if the seat breaks during a smash, I've had it. 'tis the standard fixture point though I'd feel happier using the plate you've found How are you getting both latches on the rear belts onto the one eye bolt in the back though? I originally bought a 4point, but the clips wouldn't go on safely - they need to be free and shouldn't be 'wedged against each other' The eyebolt plate is about £2 from Demon Tweeks and is FIA approved. I've got a Cobra Imola2 seat fiited so haven't got the subframe mount. My harness is a Cobra/TRS Pro superlight so has thin latches which provide enough space for both to fit with movement. I wasn't sure if the transmission tunnel was going to be thick enough to weld properly and give enough strength though. you want as shallow an angle possible with the rear belts. Any more then about 15 degree's and you risk being crushed by the harness during an accident. You should also never use harnesses without a roll cage. When you say the angle on the 'rear' belts, which angle exactly do you mean? (I'm a bit slow!) Why should you never use a harness without a rollcage? Share this post Link to post Share on other sites
hengti 2 Posted January 31, 2006 The eyebolt plate is about £2 from Demon Tweeks and is FIA approved. I've got a Cobra Imola2 seat fiited so haven't got the subframe mount. My harness is a Cobra/TRS Pro superlight so has thin latches which provide enough space for both to fit with movement. I wasn't sure if the transmission tunnel was going to be thick enough to weld properly and give enough strength though.When you say the angle on the 'rear' belts, which angle exactly do you mean? (I'm a bit slow!) Why should you never use a harness without a rollcage? I'd have thought it'd be OK - it's only spreading the load. You could seam weld a bigger plate to the underside to toughen things up if it still looks dodgey the angle DrSeuss is talking about is the angle of the rear straps from the horizontal - it's prolly about 45deg in your set up (depends how far forward your seat is). It might not be ideal, but it's the only option you've got unless you've got a rollcage to anchor it to The argument about using harnesses w/out cages is age old - there are plenty of stories of people who've rolled uncaged cars *just* after having reverted from harnesses to normal road belts (why are there some many people who do this?!!!) - apparently, if they'd have been wearing their harness, they'd have been killed, but, as it turns out, they weren't - so they were able to get out of the way of the roof as it was crushed around them ... I don't use mine on the road - only for tracks - helps keeps you in the seat I'll take my chances ... Share this post Link to post Share on other sites
DrSeuss 0 Posted January 31, 2006 As Hengti says, its the angle with the horizontal. As your thrown forwards the harness acts to crush your spine. This crushing effect is directly proportional to the angle the belts are mounted at. Harness's prevent you ducking as the roof caves in when you roll. Which can do bad things like snap your neck or again, crush your spine. Share this post Link to post Share on other sites
gti_al 1 Posted January 31, 2006 I mounted mine the other day, and i was pretty unhappy with the angle using the rear seat belt mounting hole. Here is the topic i started http://forum.205gtidrivers.com/index.php?showtopic=53613&hl= It is a much better arrangement, and it lessens the load on the top of the seat significantly. It is also really easy to do, although it does require a couple of holes to be drilled. Share this post Link to post Share on other sites
markrnorton 0 Posted February 2, 2006 This may help Share this post Link to post Share on other sites
jonD6B 0 Posted February 2, 2006 This may help Are the angles shown in the diagram a tolerance or a reference? i.e. Can the rear harnesses be between horizontal and 45 degrees or are they expected to be at 22.5 degrees? Thanks for the link. In it people have mentioned fastening the harnesses to the rear beam mounts. How exactly and where exactly is this done? When I fit a cage at a later date will I need to reposition the mounting points again? Share this post Link to post Share on other sites
Jonmurgie 2 Posted February 2, 2006 They are supposed to be anywhere between 0 and 45 degrees... I have to admit that mine aren't, though I will be sorting that out soon... I've also used the captive nut on a plate things from Merlin Motorsport (http://www.merlinmotorsport.co.uk) though I don't feel you HAVE to weld them to the car, just drill a hole through the transmission tunnel and bolt the eyelet into the plate through the bodywork... Share this post Link to post Share on other sites
