Dave McDonald Posted November 7, 2020 Report Share Posted November 7, 2020 Following several comments about the advisability of incorporating a firewall behind the rear trim panel, principally from Mick Richards and Stuart, I've made one for my TR5 currently being restored. I've used aluminium sheet approx 1.5mm thick. The main central section was easy, the two ends a bit more awkward but I'm please with end result. It will be fitted with intumescent sealing around it before the trim panel is fitted over it. Dave McD Quote Link to post Share on other sites
Motorsport Mickey Posted November 7, 2020 Report Share Posted November 7, 2020 Looking goooood Dave AND safer. Mick Richards Quote Link to post Share on other sites
Waldi Posted November 8, 2020 Report Share Posted November 8, 2020 Hi Dave, I have done the same, struggled to find a temperature resistant sealant that also remained flexible, so ended up with a silicone sealant rated to 100 degrees Celsius (only), I hope it will hold a bit longer for short term exposure. Fitted rivets on short distance for increased strength as this sheet probably will stiffen the body (torsionally), so stresses / load on the rivets may be higher than expected. Cheers, Waldi Quote Link to post Share on other sites
elclem1 Posted November 19, 2020 Report Share Posted November 19, 2020 Looks good Dave but why does the seatbelt go into the boot? Doesn’t this compromise the idea of a firewall like wise the wiring loom? I fitted one similar to my hillclimb car but the seat belts are fixed within the drivers compartment and the wiring loom passes under the rear swab and into the boot through one of the many holes left by the injection system when I changed to carbs. Thus maintaining the integrity of the firewall. Am I missing something, I usually do.! Clem Quote Link to post Share on other sites
Dave McDonald Posted November 19, 2020 Author Report Share Posted November 19, 2020 Hi Andy, Hope you're well in France. The seat belt retractable reels will be mounted in the boot on top of the inner wheel arches to give a better angle for the belts to run through the belt tidy brackets on the Mazda MX5 seats that I will be fitting. It's a detail that I cribbed from one of Stuarts built cars that I saw at the Stratford Triumph weekend last year. It stops them falling off your shoulders and stops them chaffing on the belt tidy brackets if anchored in the usual position. You're right, the necessary slot does compromise the total integrity of the Firewall, but they will be finished with an MGF belt trim in the rear trim which is quite narrow (yes, I know, sheer heresy fitting MG parts to a TR!!) so I've taken the view that the vast majority of the area being covered is better than nothing. Believe you me, I have no intention of hanging around for long in the car in the event of a fire and the firewall, even with this minor perforation, should give me a few extra precious seconds to evacuate. I'm more relaxed about the wiring loom opening as the loom pretty much fills the rubber grommet so again only a minimal reduction in overall improved safety. Dave Quote Link to post Share on other sites
PodOne Posted November 19, 2020 Report Share Posted November 19, 2020 Hi Dave I've some MX5 seat to fit at some point any chance of a picture of where the reels are fitted in the boot? Thanks Andy Quote Link to post Share on other sites
Bfg Posted November 20, 2020 Report Share Posted November 20, 2020 (edited) For whatever it's worth .. a couple of photos I have saved into the same file happened be next to each other. Although they're of a TR3A and an E-type ..and so very different in their structure / body construction, fuel tanks and suspension, I found the similarities in this behind-the-seats space interesting . . . It's quite clear which is the safer as well and very much stiffer construction. Pete. Edited November 20, 2020 by Bfg Quote Link to post Share on other sites
stuart Posted November 20, 2020 Report Share Posted November 20, 2020 7 minutes ago, Bfg said: For whatever it's worth .. a couple of photos I have saved into the same file happened be next to each other. Although they're of a TR3A and an E-type ..and so very different in their structure / body construction, fuel tanks and suspension, I found the similarities in this behind-the-seats space interesting . . . It's quite clear which is the safer as well and very much stiffer construction. Pete. Not really a fair comparison when you see the size difference, The Etype has the tank in the side of the spare wheel well so nowhere near behind the back seat area. Stuart. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted November 21, 2020 Report Share Posted November 21, 2020 (edited) Now I have always thought the design of the TR fuel cap gave little protection from fuel leakage if the car was inverted. The early fuel cap with the external release being easily unclipped if the car is sliding upside down through a hedge. The other issue would be venting systems. TR2-early 4 have a proper vent pipe system that will not allow fuel escape even when the car is inverted. Later TR4-6 have a vent hole through the cap seal. That relies on the fuel cap seal being good, which they are not on the fibre sealed TR2/3 caps. Do RAC scrutineers not require the side clip of the fuel cap to be sticky taped in a fixed closed position or am I dreaming? I have ignored the magnetic NAS TR250/6 fuel cap that will probably undo on a bumpy road. Cheers Peter W TR2-5 Better TR6 European Best the optional locking cap pt no 571086 Edited November 21, 2020 by BlueTR3A-5EKT Quote Link to post Share on other sites
Hamish Posted November 21, 2020 Report Share Posted November 21, 2020 (edited) 3 hours ago, BlueTR3A-5EKT said: Do RAC scrutineers not require the side clip of the fuel cap to be sticky taped in a fixed closed position or am I dreaming? Cheers Peter W TR2-5 Peter I have only had 1 scrutineer ask me to tape up this type of filler cap. Edited November 21, 2020 by Hamish Quote Link to post Share on other sites
BlueTR3A-5EKT Posted November 21, 2020 Report Share Posted November 21, 2020 8 minutes ago, Hamish said: Peter I have only had 1 scrutineer ask me to tape up this type of filler cap. Interesting. 'Taping up' was one of my tasks when brother hill climbed and sprinted his TR2, and I recall the filler cap and all lamps were on the scrutineer check lists. Peter W Quote Link to post Share on other sites
Motorsport Mickey Posted November 21, 2020 Report Share Posted November 21, 2020 10 years of racing and 5 years sprinting...my caps were ALWAYS taped, I never need a good excuse not to kill myself. Shock impact can easily snap the cap back and forth causing the over clip to flip open, I've even accidentally impacted the side of the cap myself and "sprung" it open. I always thought I had a larger investment in my safety than a scrutineer. Mick Richards Quote Link to post Share on other sites
Dave McDonald Posted November 21, 2020 Author Report Share Posted November 21, 2020 8 hours ago, Hamish said: Peter I have only had 1 scrutineer ask me to tape up this type of filler cap. This isn't an issue with my race TR6 as I have a bespoke foam filled aluminium tank in the boot with a screw cap. The hole in the rear deck where the original fuel cap would have been located is currently occupied by the mounting for the mandatory rear rain light. Dave Mcd Quote Link to post Share on other sites
Harbottle Posted November 22, 2020 Report Share Posted November 22, 2020 12 hours ago, Dave McDonald said: the mandatory rear rain light. Rain, what rain? Quote Link to post Share on other sites
roy53 Posted November 22, 2020 Report Share Posted November 22, 2020 9 minutes ago, Harbottle said: Rain, what rain? you should have been with us at Castle Combe Quote Link to post Share on other sites
DaveN Posted November 27, 2020 Report Share Posted November 27, 2020 Just replaced my thin alloy firewall with a sheet of stainless . It was an absolute mare to work with as it was considerably thicker! I fitted it behind the rear deck lip so it wouldn’t be visible with the trim panels screwed in. I fitted a new alloy tank at the same time. Hopefully a nice stiff sheet of stainless will stop any movement at the back and negate the chance of any of the tank lugs failing, which I believe has happened in the past! Quote Link to post Share on other sites
john.r.davies Posted November 28, 2020 Report Share Posted November 28, 2020 DaveN, Stainless is hard work! Dave McDonald, I have a similar alloy firewall, and to run the seat belts at the correct angle, I mounted a stout tubular bar across behind it, drilled through the wall and into the bar to mount threaded eye bolts. They are sealed with intumescent where they go through. You have retractable reels, but they could be mounted on a plate, similarly mounted on a cross bar behind the fire wall, and bolted through. This would remove any need for slots in the wall. The cross bar is between the rear wheel arches, and by being bolted to the fire wall, in combination they provide significant stiffening the the rear body, that DaveN hoped for. JOhn Quote Link to post Share on other sites
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