Chimaera performance mods. Where do I start?

[matt101]

I have few questions for you on performance mods to a Chimaera 4.0. Im not looking to transform the car into a complete beast but 20-30 BHP extra and a bit more torque would be great.

Here is my list of things that I know are available/possible without going too crazy but im not sure what kind of gains could I expect if I had all of this done?



1. Removal of pre cats

Is it best to replace the manifolds when this is done?(ACT)
Do I need to do anything with the Lambda sensors at this stage?

2. Removal of main Cat

Is this more trouble than its worth? (obviously needs to be put back at MOT time)
Will the car HAVE to be re mapped to do this or will it be OK on the std chip?
Will I notice a big difference with all the cats removed?
Will it spit flames? (most important!)

3. Replacement exhaust (rear)

4. ECU upgrade

Mark adams with rolling road setup or are there alternatives?

5. Have I missed anything else that can be done without major engine work?

6. Would I need to look at upgrading brakes etc at this stage?

7. Insurance

Will they no longer speak to me?


There must be a few out there that have had most of the above done so would love to hear how much difference this made and how you went about doing it.


cheers,

Matt

[mongoose]

spoke to mark adams myself about removing the cats.he told me that only precats are worth removing as main cat does not restrict flow that much and you definately need it come mot time.removing precats improves the bottom end smoothness but you only gain a couple of bhp.surprisingly he said you dont need to remove or alter lambda sensors and a re-chip will improve things further but you dont have to do it.its worth mentioning that we were talking about my griff,which is a 5l hc spec.

[whitechimp500]

Immediate performance gains.
1)Remove the spare wheel and jack and buy 2 cans of tyre weld.
2)Use Shell Optimax.

For the future ?
Remove pre-cats.
Remove Main cat
MA Tornado Chip and R/road.
Brake upgrade.
Sports Exhaust.
Nitrons.
Roll bar.
Harnesses
Carbon Plenum.
Track Days.
Wheel/Tyre upgrades.
Magnecor leads.
Alloy bits for interior.
Financial Ruin.
Total Mental and Physical Breakdown.

[GreenV8S]

It's a question that comes up time and again so a search of the archives might turn up some interesting thoughts. I would say it depends on what level of experience you have as a driver and what sort of thing you want the car for. If you go drag racing, I guess you would start with power mods. If you're a typical enthusiastic driver like the rest of us, I'd suggest you start with driver training, get on track with exper tuition. If you're going on track and find you're cooking the brakes then upgrade them, if you can corner the car on its door handles and want more mechanical grip (at the expense of a slightly more demanding drive) stiffen the suspension, spend money on really good dampers (Nitrons, for example) and get the suspension set up by an expert. You will need to notify your insurers of any change to the car, but I wouldn't expect any premium increase from these changes.

If you think you've really got the skills to exploit the full capabilities of the car and got it handling the way you want, more power is the obvious next step. You probably don't want to hear this (and you may not believe it when you see my profile) but unless you already have a 5 liter car, trading up to one is going to be the cheapest and most reliable power increase you can get. However, if you want to stick with what you've got, there are a couple of guys who really know how to get the most from these engines who are well worth talking to. The first one is Tim Lamont of ACT, he makes and sells state of the art induction systems for the Rover V8. In my experience he is the best sort of enthusiast you could ask for. Bearing in mind he runs ACT, you will be surprised how impartial the advise is and it's very much a soft sell. I would trust Tim not to sell it to you unless it's right for you. The other person to talk to is Mark Adams, he knows the fuel injection system inside and out, and can set it up to provide optimum driveability. When he did mine the car was transformed, and I was surprised to find how small the power gains were. It felt like a lot more because the engine was so much more responsive. The first round of upgrades to the V8S consisted of cam/heads/ACT induction and after a Mark Adams set up it gained nearly 40 bhp against the standard engine, so this sort of gain is entirely feasible, and these guys can advise you how to get it.
They do a lot of work together and between them they have a huge amount of experience and can advise you on realistic costs and power gains. Bear in mind you will also have to declare these mods to your insurers. If you start with brakes and suspension then they should be fairly sympathetic, they let me develop mine quite a long way with just admin charges every time I notified them of a change.

I would still advise you not to jump in to power gains, and to think seriously about trading up to a more powerful car rather than throwing money at the one you've got. But I know these things often aren't decided based on common sense so you may well want to develop the car you've got. In which case, these are the guys you should be talking to.

Here's a handy link to ACT I found at the top of this edit page, hope it works!

www.pistonheads.com/admin/bs/redirect.asp?id=430&way=ban

Cheers,
Peter Humphries (and a green V8S)

[MikeyT]

Thoughtful, detailed response Pete, as expected. Top stuff from someone who has done it.

[shpub]

This is pretty heavily discussed in the Bible 2 with some example dyno graphs. Totally agree with the upgrade path as it is the easiest and most reliable way of upgrading the car. Having said that my Griff 500 runabout has been tweeked and I keep having to say No it's a runabout. Play with the 520!

One word of warning. In my extensive experience double your first estimate of costs and it will be about right! If you want some good examples of what Pete and I have done... www.t-v-r-services.co.uk in their engine upgrades section. If you want to see how to spend the Gross National Product of a small country, the 520 story is interesting reading.

Steve
www.tvrbooks.co.uk

[kevinday]

Steve the T-V-R website only shows the upgrades to the 390, not when you upgraded it to 520. Will they be posting this sometime soon?

[shpub]

Try www.t-v-r-services.co.uk/520_story.htm

The car has been rebuilt, is now TVR purple has a towbar with a trailer carrying a set of slicks and wets. The car now competes in full modified class but is still road legal. I drive to the circuit. Unhitch the trailer, bolt on the slicks/wets and away we go. The towbar unbolts to save weight.

The 520 makes a pretty good tow car. ..

[alex200mph]

The 520 makes a pretty good tow car. ..

Please don't tow a caravan with it though

[Size Nine Elm]

Chimaera performance mods. Where do I start?

When you do start, make sure you already know the answer to 'Where do I stop?'

I've done the following to my Chimaera 400:

Pre-cats removed
MA chip
Front disks grooved/drilled
A few track days/driver training days

I've ordered a roll bar which should (as a side effect) improve the stiffness of the car; my next mod would be shocks - but the cost is starting to show...

[matt101]

Thanks for all your comments. Come to mention it I may well be spending some time on Track soon so this will probably prove that further instruction is required!!!

Size nine

Tell me how your car felt following the chip and de cat! Is there a big difference?????


Cheers,


Matt.