Power Upgrade, Supporting Mods?

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TVRS3
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Power Upgrade, Supporting Mods?

Post by TVRS3 » Wed Apr 05, 2017 8:23 am

Hi all, I hope the thread title makes sense.

I am in the early stages of researching an FB based project. Essentially, I would like to go down a restomod route with it and have a FD engine fitted. Obviously this would be a fairly big jump in power, and so other areas of the car would require upgrading to cope.

My first question is regarding the brakes. I would imagine (though I'm prepared to be proved wrong), that the standard brakes would not be up to coping. So what are the options? I have seen people changing to FC brakes, but this seems no require hubs being swapped; is this a significant upgrade to make the work worthwhile? There seem to be no bolt-on big brake kits, so any upgrade appears to be of the home-brewed variety. Would that be a fair assessment?

Also, regarding suspension, it seems that coilovers can be quite a lot of work to fit (especially the rear). Has anyone ever used Techno Toy Tuning, as they seem to offer bolt-on packages? They do seem expensive, so I would probably not go this route anyway but I am interested to here your thoughts.

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gt_james
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Re: Power Upgrade, Supporting Mods?

Post by gt_james » Wed Apr 05, 2017 2:10 pm

Why not T2 swap? Much easier and has been done more often. If you're running stock FD power levels you might get away with keeping the back axle the same, but if you're going for big turbo power then the rear end needs upgrading. In Aussie they use hilux axles, in america they use Ford truck axles.

S3 brakes will be fine for the road, even quick race cars use stock brakes. Unless you've got really wide sticky rubber the stock brakes are capable of locking up most tyres. There are not many options of big brake kits, but turbo 2 brakes can be made to work with brackets and spacers machined giving 4 pot calipers. It will depend on what size wheels and tyres you intend to run. Its worth noting that If you need bigger brakes then the spindles themselves probably need upgrading too.

Coilovers are not much work, see my budget coilover write up. Depends how serious you want to get though, if you want to have better handling and a slight drop in ride height then some lowering springs, Koni AW11 MR2 front dampers drop into stock strut tubes and mustang/E30 dampers will work on the rear. If you want much lower and stiffer springs you need to go to coilovers, and can be done quite easily, but if you seriously want to improve handling you will need to do other work as the geometry goes out the window on these cars when lowered much. The rear roll centre on the watts link is far too high and the upper arms bind and the pinion angle gets messed up. The fronts wont go very low whilst maintaining travel unless you modify the strut tube to work with a very short stroke damper. Most people use a koni 8610 and 2" tubes, like the Techno Toy Tuning set up.

KiwiDave
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Re: Power Upgrade, Supporting Mods?

Post by KiwiDave » Wed Apr 05, 2017 4:14 pm

gt_james wrote:. Koni AW11 MR2 front dampers drop into stock strut tubes .
Correction , it's AW11 MR2 rear dampers that fit into stock strut tubes

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Chud
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Re: Power Upgrade, Supporting Mods?

Post by Chud » Wed Apr 05, 2017 9:36 pm

As James said, fitting a REW lump is a bit trickier in comparison to a S4 or 5 swap but obviously thats not to say its impossible as it has been done. Back to your original question - an option I am currently looking at for braking is a kit made by the PAC guys in Australia - http://www.pacperformance.com.au/catego ... ories.aspx

Coilovers are available from Gaz for decent money or follow James' advice, we are waiting on Acbron coilovers at the moment but less said about that the better at the moment.
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TVRS3
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Re: Power Upgrade, Supporting Mods?

Post by TVRS3 » Thu Apr 06, 2017 8:38 am

Thanks for the feedback chaps. Its all much appreciated.

Regarding engine choice, the FD unit was just an initial idea - expect a thread in the engine section going into all this soon!

Regarding supporting mods, from what you guys have said, I would imagine S3 brakes would be more than sufficient. I might venture out on track occasionally, but this will be primarily a street car so standard brakes in good working order sound fine.

The suspension question sounds a little more complex. I would like to lower the car (mainly as I like the look), but would not lower it to the detriment of handling. Stiffly sprung I'm happy with as long as the pay off is fun round corners! For reference, my current TVR has GazGolds all round and I'm pleased with that setup.

The question of knocking the geo out seems a little more involved. For example, the question of the roll centre being too high looks like it can be solved with spacers. However, my knowledge of suspension is being stretched...! On the Techno Toy website, they have a lot of other suspension parts but I must be honest, I don't know what some of them are for...

Lastly, do you know what kind of power the standard rear diff can take before an upgrade is required? And is there an easy way of getting an LSD in there?

Sorry for all the questions. I very much appreciate your patience in answering me!

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Re: Power Upgrade, Supporting Mods?

Post by Chud » Thu Apr 06, 2017 1:07 pm

Another option you could consider is doing the front subframe swap from an FC so that sorts out your front suspension and braking requirements in one hit. The whole brake debate really depends on how you drive - I give my car a kicking eveytime I'm in it and the stock brakes just aren't up to it but then you might not be as enthusiastic as I am. :D

I'm running a stock LSD which Tool sourced for me - has so far dealt with the power okay but I'm not sure how long for - if you go S3 they're 26 spline and you'll either have to get lucky here or get one from the states.
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ian65
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Re: Power Upgrade, Supporting Mods?

Post by ian65 » Thu Apr 06, 2017 10:20 pm

over 200bhp you really want to upgrade from single pot S3 calipers.
As Chud says, a FC subframe swap will provide most of the upgrades you need inc 4 pot calipers but that swap is a nest of spiders all on its own and throws up more problems than it solves.... plenty of people do get it to work but to what degree of success is hard to quantify.
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TVRS3
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Re: Power Upgrade, Supporting Mods?

Post by TVRS3 » Mon Apr 10, 2017 4:53 pm

Thanks again for the info guys. I would probably not go down the FC subframe route, purely as I think I'd prefer to keep it with the stock basic architecture. That may change though!

Brakes-wise, I guess I'll have to see what the stock ones are like. I ended up upgrading my TVR front brakes to Fiesta ST150 items which required custom spacers being made up, so I'm not totally unfamiliar with getting bits to fit. Though designing custom caliper brackets with good safety tolerances will need a bit of thought.

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Re: Power Upgrade, Supporting Mods?

Post by TOOL » Mon Apr 10, 2017 5:19 pm

Hi, and welcome to the forum.

The 26 spline 7 inch LSD will handle all the NA power you can throw at it. The axles are stronger than earlier cars too.
A turbo motor will kill it if you are hard on it.

Defo upgrade the front brakes. My opinion. Caliper brackets and front hubs, plus FC f pots and standard FC discs. Cheap enough to do. You can buy the parts in Oz.

Slam it for the looks and the improved handling.

TOOL
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TVRS3
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Re: Power Upgrade, Supporting Mods?

Post by TVRS3 » Mon Apr 10, 2017 6:27 pm

TOOL wrote:Hi, and welcome to the forum.

The 26 spline 7 inch LSD will handle all the NA power you can throw at it. The axles are stronger than earlier cars too.
A turbo motor will kill it if you are hard on it.

Defo upgrade the front brakes. My opinion. Caliper brackets and front hubs, plus FC f pots and standard FC discs. Cheap enough to do. You can buy the parts in Oz.

Slam it for the looks and the improved handling.

TOOL
Many thanks!

If I were to go bigger power, do you know what the options would be for a LSD at all? Or maybe a better question, what would the LSD you mention be able to take? 200bhp? 300?

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