DHC front bumper weights

[troydeon]

I did a search and found one post that indicated that removing the weights didn't seem to affect shaking...
Anyone out there remove the weights and what is your opinion of the result?

Troy
1980 TR7 DHC

[DNK]

Seems that with all the other new technologies ...ie... better bushings and stuff the weights don't make a difference if removed
IIRC

Don
Stick a Wedge In It
80 TR7 V8 Kick in the pants

[supercass]

I find it difficult to believe that the designers would mess around attaching large heavy and no doubt expensive weights to the front of bumpers to reduce body shake if in fact there were no discernible benefits. supercass

[Orange Rag]

I removed the weights, centre pin and rubber spacers.
Not only do I not notice a difference the bumper now fits tight to the body like on the coupe.
There's pictures posted resently under "Bumper swap FHC to DHC"
Again I can't tell the difference other than better looks!

[Hasbeen]

Yep, I could detect no difference on the road.

However with that hefty bumper bolted solidly to the front chassis like rails, the thing does feel more solid in it's structure.

Hasbeen

[trickyx12000]

hi, if the engineers/ bean counters at triumph/ British Leyland could have saved just a 1 penny on a cheaper front bumper set up would you not think they would have..
example... why does the cambelt on a car always fail if not changed.. because they are made to a price.. about 10,000 miles over the recommended..

from my understanding of it, the idea goes back to cars in the 1920's or something... you have a ridged piece of steel mounted to the car frame on rubber blocks.. ( the weights must be there for added mass) when you hit a bump or the like the body on a car twists and shakes... these twisting/ shaking actions are dampened down by being a bolted to something ridged.. the rubber lets it shake a bit, to soften the ride...reducing the flexing but not making it too ridged.

bit like the buildings with the ball in the middle of them to help stop the structure failing during a earthquake.
here have a link..
http://en.wikipedia.org/wiki/Tuned_mass_damper

so doses any one really think that mucking about in their garage at home and driving it once a week they can find out more about a car, than the guys going out over the same road/ track day after day with test equipment wired to everything.

perhaps we could start a topic on spot welds failing ready for the later enquires..

I notice the rubber mounting blocks are getting hard to come by, so i'm up for anyone's..... no longer required.

[Hasbeen]

Well I don't know trickyx12000, but when I did suspension work on the original 327 Bathurst Monaro at lang Lang, [GM test facility in Victoria], I managed to knock 4 seconds off the times the companies design engineers, & test drivers had managed to do, with changes to spring & shock rates, roll bars & settings.

If they had called us in earlier it could have been another 2 seconds, but some things were already set in stone, & couldn't be changed so close to production. That was in 2 days, not the 3 months they had been working with prototypes.

Boffins are great, but as we can see with the global warming tomfoolery, they can get it dramatically wrong when groupthink takes over. The next time a whole country goes down a blind alley will be the millionth time or there about. Just think wind power generation. The fact that a small company like Triumph could go on a wild goose chase is not very surprising. Neither is the fact that the practice did not become common.

It made no difference to mine, in the way I & my son use it, although as I don't drive it on corrugated gravel roads, I can't guarantee it won't for some. The theory is great, & perhaps a strain gauge could find a result, but none detectable to a mere human.

However I think the extra stiffness of the front end of a solidly mounted bumper is more than enough compensation.

Hasbeen

[trickyx12000]

hi,
can we not agree a racing car is a completely different beast to a production car..
if you were preparing a car for racing would you not be at least seam welding parts of the car..? and want to remove any unneeded weight?
the average driver of a tr... when it was built... 5' 6'' accountant !! if we believe the ad's would not be interested if he could knock 5 seconds off his trip to the office.. but if his filling fell out!
I have tried to explain what I was told for the reason its there.....every one can make their own mind up... personally in this matter i'll keep mine standard...


I have already swapped one set of the rubber blocks not on my current tr... but the one I had in 1987.. the guy who pointed out to me that the rubbers were knackered and told me the reason behind them.. was one of the, not design engineers but one of the engineers that built the small batch of TR8s and 7s pre production cars at longbridge..

has for global warming... there's been a lot of piffle talked about that too...

[Hasbeen]

The 500 was stock standard production cars in those days.

Holden sold 1400 of the 327.

Hasbeen

[FI Spyder]

I think we might be arguing how many angels can dance on the head of a pin here (a lengthy discussion of ecumenical councils during the middle ages). Take off, leave them on, what ever, won't make much difference in that most will experience what they expect to when they do. I took mine off only because I had my bumper off to check condition of front end and I wanted to see the effect. Can't say I can see any. If I have reason to have it off again I may put them on to compare again. I got much more things to do that come ahead off it though, house renovations, yellow, TR7, work to be done on Integra and Tercel, two Spitfires waiting in the wings for example. Don't need any more make work projects.[:p]

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[Orange Rag]

I know why they are there and how they work but the manufacture must build the car to meet all customers needs. I drive on smooth paved roads while the designers had to build for cars to be driven on all sorts of surfaces, if I was driving on broken or colbstone roads I'd leave them on.

[HDRider]

It is not an uncommom practice. All 60's convertible American cars have sand fill steel canisters at all four corners of the car to help eliminate scuttle shack. I think thta thye use this approach as all of the cars in question were designed as coupes so these are fixes to help the requiered chassis modifications.

That said I did remove the steel weights from my TR8 with no adverse effects so far. I have been hesitant to do it on the 7's as the motor is not as smooth running being a 4 cylinder.

Edward Hamer
Petaluma CA

[nick]

The front end on both of my cars shake at the same speed even though they have been completely reconditioned. New bushes, ball joints and shocks. I removed the weights from the DHC and there was no change. I do drive solely on paved surfaces so what the effect would be on a rough road is beyond the scope of my testing.

[img][IMG]http://i615.photobucket.com/albums/tt234/nickmi/TR7%201975/Yellow.jpg[/img]
nick
'79 TR7 DHC
'76 TR7 FHC

[Beans]

Trickyx12000 does get my support here.
Probably on smooth roads removal of the balancing weights won't have much influence.
But sadly we're not living in a perfect world.

<center>
<font color="blue"><i>1980 TR7 DHC (my first car, now restored and back on the road)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
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[trickyx12000]

hi,
<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">The fact that a small company like Triumph could go on a wild goose chase is not very surprising. Neither is the fact that the practice did not become common.

<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"> from the link I posted<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Almost all cars will have one mass damper, some may have 10 or more.<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

let us not forget the TR7 was never designed to be a convertible..