|HBZ Front Bumper - Installation / Observations|
NB. With a Threshold billet bulkhead installed you may unfortunately find that the HBZ bumper may not fit (pic A) or will be so tight as to potentially cause other issues such as a higher risk of binding in a head on impact, where metal against metal is used.
In such a situation damage could also occur to the finely machined billet bulkhead 'sleeves' that retain the bumper arms. Reason enough for using the stock BH, in this combination, allowing metal to slide against plastic.
The Threshold part is CNC machined, the HBZ bumper is not and hence variances in fit will be inevitable.
So to install the HBZ bumper, the Threshold bulkhead had to be removed and replaced with the stock part.
NB. Ordinarily, (HBZ bumper use excluded) the Threshold would be my first choice of bulkhead.
The front section of the baja was stripped down just enough to get the stock bulkhead back in. It was pretty straightforward from then onwards apart from the sway bar situation.
No sway bar, probably no problem. Bearing in mind that these HBZ bumpers will inevitably vary one to the other – this is just one installation experience.
The captive lock nut in the top sway bar clamp prevented the flat cross brace in the HBZ bumper from interlocking with the underguard (skidplate) screw postions. See pic.B
Probably important as these two screws which fit into the skid plate ‘plugs’ are the main fixing for the front of the bumper. The rear 'arms' of the bumper being retained through the bulkhead with plastic c-clips.
nuts were ground down (pic C) to allow the cross brace / bumper to fit
flush immediately above the clamps. This allowed the screw plugs to now
slot into the HBZ holes.
Just as a side note, the Lunatik bumper is more of a rigid type being anchored top and screwed bottom. The HBZ one is only fixed at the top with two screws into the top of the skidplate of the stock bumper set.
From initial observations it would seem that this would have a bit more flex in a head-on hit, for the above fixing reasons. Probably a good thing.
That is to say, the stock skidplate / front bumper assembly - (#85420/3) is designed to have some flex in it. Admittedly not enough to save the chassis from a bad crash, but some nonetheless. The arms of 85420/1 which thread through the upright part of the bulkhead, and are restrained by the c-clips (85420/8 ) will also have some horizontal movement.
There are a few good bumper options out there and certainly room for more.
I think a comprehensive bumper design with some sort of spring steel plate / crumple zone behind or integrated with the skidplate would not be a bad thing (in conjunction with Diegos bottom plate / TRs top plate) – My only other comments are re the layout of the perforated mesh – IMO should have been symmetrically laid, horizontally or vertically, rather than random.Also watch out for any rear side sharp edges on the mesh, may want to file them down carefully.
|Original forum thread and comments detailed at http://www.hpibajaforum.com/forum/showthread.php?t=30411|