Modifiying Strut towers

[thedooga]

Hi there, Ive had a read thru the hobby car manual and can't seem to find any info,

I have a 1958 Ford Anglia, that im currently fitting a 1UZ to, and have removed the old steering box system, and replacing it with Toyota Ke70 Corolla suspension and steering etc. But what im wanting to know, proving its done correctly, am i allowed to cut the top off the strut towers, to change the mounting pattern, and lower the height?

I have done a mock up of what im doing, and can easily be changed to suit certain requirements.

At the moment it is constructed of 3mm mild steel. Also to make life alot easier, i would prefer to tube front like the sample photo, but retain the factory rails, and not fit a roll cage, what is involved with this? Thanks for your help.

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[Todd]

Sounds like an interesting conversion.

Your first option shouldn't be an issue, assuming you're building enough strength into the setup, which your example looks like you are. So I'd suggest that's the better way to go.

The second (tube) option is a touch harder, as you're then sending the load from that area through a small area, rather than the monocoque setup. It could be done, however, you'd need to work out how to attach the tubework to the body of the vehicle in such a way that it's spreading the loads as to not create stress fractures.

Good luck with it.

[thedooga]

Thank you for your reply Todd, I would prefer to do the tube front end so will have to workout some stuff and submit it for approval.

Second thing, I spoke to a local certifier, and pretty much had no luck with getting advice on a way i can do this, but my questions is, the car is a monocoque fame setup, with very light chassis due to being such a small car, and originally having very little power,

I have read the hobby car manual and it states that you need to keep no less than 60% of the original chassis to keep it as a non scratch built car. I am wanting to tub the rear end and make new chassis rails to suit the 4 link rear end, as i cant keep the factory items as they are to wide apart for the wheels I will be running. the factory rails stop at about that 60% mark. But what am I able to do as to strengthen up the original parts to allow for this? I really don't want to step into the scratch built category if I can avoid it, here a few pics as to what ive got and what I would like to do. Sorry for the big novel.

[thedooga]

this is what im thinking for the rear end


I would like to do something like this also, keeping with the same design as factory, but replacing the folded up chassis with 75x50x3 SHS as per hobby car manual. And making a new floor, as there is rust in certain places and would be alot easier to just start again with all new stuff. These photos are from a mate that has just done a Datsun 1200. Cheers again for your help, much appreciated

[Todd]

If you're replacing the floor anyway, then running complete new rails front to rear would be the sensible option.

With the mods you're doing, there's really no down sides to it being registered as a scratch-built, and the upside of three year WOF's as it's treated like a brand new vehicle.

You could mess around with keeping the factory rails in there somehow, running new rails as chassis-connectors, but it'd be a whole lot more work, and only to create a vehicle that's not as well-engineered/strong as the easier option.

Often people try to avoid the scratch-built definition, as it requires lap and diagonal seatbelts, however being a 1958, it already requires these, so there's no downside to it at all.

**edit -The other thing that a scratch built will need is two speed wipers and burst-proof door locks. I'm unsure if your car had those from factory or not. 

[thedooga]

Awesome thanks for the info Todd, ill have to retro fit new door locks, but that ain't that hard. So full new chassis it is then, ill have to have a read of the hobby manual, but im guessing i need to draw up a design and submit it for approval? As in my earlier post, it should make it easier to incorporate the tube front end and spread the load accordingly. (im a welder/fabricator my trade so its all easy work for me) Well this is going to fun wee project now!!

[Todd]

Good to hear.

The front suspension setup, assuming you're creating your own arms/custom geometry will require TAC Design Approval, however, since it's the same cost to you to have TAC inspect this element, as it is to offer engineering feedback on the whole project, the more information you can include on the application, the more it will benefit you.

You'll find more info about the Design Approval process in the Car Construction Manual, or here: www.lvvta.org.nz/approvals.html#design

Good luck.