The new acquistion 430 Chimaera

The new acquistion 430 Chimaera

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Discussion

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
Well it is finally happening. A few little hurdles to overcome like how do I get the V5 in my name when am not in the UK? There are a few little niggles to be addressed but the garage that did the pre Purchase inspection will be dealing with those.

Now the issue that concerns me the most is that he says it suffers some low speed shunting which of course is not uncommon and the obvious answer is to upgrade to an MBE or Canams set up ............................................ but that is not in the budget to be able to do so. So emailed Kits and Classics about their remapping service. Joolz says that he cannot guarantee that it will eliminate the shunting but of course the mapping session should help her run as well as she can.

So started reading up on the issue and Mathew's Griffith came up as it still runs the standard system but of course he also has the ACT twin plenum fitted but how much did this help? or was the shunting issue solved before this?

Any advice on the ways to help eliminate this would be appreciated.

Belle427

9,673 posts

239 months

Saturday 26th August 2017
quotequote all
Most of what ive read seems to point more at the camshaft then anything else, so im not really sure what you can do about this unless you budget to change it.

TV8

3,210 posts

181 months

Saturday 26th August 2017
quotequote all
If you read the period road tests of these cars, you don't see to many references to shunting. Expectations of smoothness will be lower back then and I would look at the air intake pipes and the ignition side of things to make sure all is well.

The early cars have a funny colour air in take that looks to have come from a small tumble drier. These can collapse internally. I changed both of mine for the solid pipe work that ACT sell and then make sure the ignition is in good order. You might be pleasantly surprised how smooth they can be!

TR4man

5,312 posts

180 months

Saturday 26th August 2017
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Hallelujah

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
Yes smooth bore induction is going to be done am also enquiring about the larger AFM. Not sure if this will help or not.

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
Belle427 said:
Most of what ive read seems to point more at the camshaft then anything else, so im not really sure what you can do about this unless you budget to change it.
She has good history and fairly low mileage so cam should in theory be OK.


carsy

3,019 posts

171 months

Saturday 26th August 2017
quotequote all
The 4.3's run a Kent 214 cam as standard. This cam will shunt low down on these motors end of. It was originally designed for use with a carb not efi and a plenum. However once spinning its lovely. Do you know if your still on the original cam ?

Richening the low rpm range via Jools will definately help though.

Putting in a milder cam will also sort it.

Or go the dual plane manifold and self learning fitech injection thats recently been spoke about on here.

Belle427

9,673 posts

239 months

Saturday 26th August 2017
quotequote all
Brithunter said:
Belle427 said:
Most of what ive read seems to point more at the camshaft then anything else, so im not really sure what you can do about this unless you budget to change it.
She has good history and fairly low mileage so cam should in theory be OK.
It's more to do with the design of it as above.

QBee

21,371 posts

150 months

Saturday 26th August 2017
quotequote all
I have a smooth bore kit that I had on my car until a few months ago, and a 20AM AFM that is a matter of weeks old.
If you want Jools to try them I can drop them off to him, sale or return. He is only 40 miles from me, and I have a cold start puzzle that could do with his attention and Emerald mapping skills.
The 20 AM was about £120 from memory, the smooth bore kit £180. I would be looking for 50% of anything used.
He would need to modify the wiring for the AFM, it uses a different plug. I do have the plug still.

Final question - geographically where is the car at present?

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
QBee said:
I have a smooth bore kit that I had on my car until a few months ago, and a 20AM AFM that is a matter of weeks old.
If you want Jools to try them I can drop them off to him, sale or return. He is only 40 miles from me, and I have a cold start puzzle that could do with his attention and Emerald mapping skills.
The 20 AM was about £120 from memory, the smooth bore kit £180. I would be looking for 50% of anything used.
He would need to modify the wiring for the AFM, it uses a different plug. I do have the plug still.

Final question - geographically where is the car at present?
Near Preston in Lancashire. And yes the induction and AFM are of interest.


Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
carsy said:
The 4.3's run a Kent 214 cam as standard. This cam will shunt low down on these motors end of. It was originally designed for use with a carb not efi and a plenum. However once spinning its lovely. Do you know if your still on the original cam ?

Richening the low rpm range via Jools will definately help though.

Putting in a milder cam will also sort it.

Or go the dual plane manifold and self learning fitech injection thats recently been spoke about on here.
I think it is still on the original cam. It has not been mentioned that it has been changed.

PhilH42

692 posts

108 months

Saturday 26th August 2017
quotequote all
Well done on finally taking the plunge.

Just my humble opinion, but I'd take up Anthony's offer of the ACT kit as poor breathing can have an effect on shunting, not that mine has ever been that bad but better when I fitted the kit and almost nothing now, mine runs a Kent 218....then take it to Jools! Ain't nothing guaranteed in this life and certainly not on a tvr, but for what he charges for a chip and tune its a no brainer as a first port of call and before considering any really costly changes....its amazing what can be achieved when properly set up and not just talking performance.

QBee

21,371 posts

150 months

Saturday 26th August 2017
quotequote all
Jools is a proper TVR engineer, by the way. He gets a lot of press on here for his ECU skills, but he covers all jobs. Hence my comment about getting him to fit stuff for you.

Preston means X-Works to me - in which case you have made a good choice of inspection engineers.

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
QBee said:
Jools is a proper TVR engineer, by the way. He gets a lot of press on here for his ECU skills, but he covers all jobs. Hence my comment about getting him to fit stuff for you.

Preston means X-Works to me - in which case you have made a good choice of inspection engineers.
Spot on Heath is on the job.

QBee

21,371 posts

150 months

Saturday 26th August 2017
quotequote all
Brithunter said:
QBee said:
Jools is a proper TVR engineer, by the way. He gets a lot of press on here for his ECU skills, but he covers all jobs. Hence my comment about getting him to fit stuff for you.

Preston means X-Works to me - in which case you have made a good choice of inspection engineers.
Spot on Heath is on the job.
I can post the bits to either of them. I know them both so can trust them. One thing about the ACT smooth bore induction kit - it comes too long, and one then cuts it to fit. Therefore mine was cut to fit my car, so may not fit yours. Happy to send it anyway, as that's the only way to find out. Personally, I would be very surprised if it sorted the shunting, unless your car has a badly kinked elephant trunk.

jazzdude

900 posts

158 months

Saturday 26th August 2017
quotequote all
I'm not too sure about the 4.3 but my 400HC is also supposedly prone to shunting compared to a standard 400.

It had had all the ACT smooth bore stuff on it when I bought it including the Decat Ypiece, carbon trumpets and still shunted. I changed all the ignition components and cleaned the Injectors, ditched the plug extenders and changed the sparks to 6s, this improved things but the shunting was still there.

Then I burned a TVR green tune map onto a EPROM chip and changed the tune resistor to 470ohm and the car is now so smooth, practically no shunting and is even quieter and more refined than ever.

I stress that this was not on a rolling road, does not have a custom map on it and cost me about £50.00 but the car is so good that I am now in two minds whether to replace the ECU this winter.

You can throw all sorts at these cars but I have since learnt that with cats and emissions mapping on the standard 14cux, dialing out shunting is very difficult as the ECU is trying to not destroy the cats with fuelling that also compromises the low speed drive ability of these cars.

Going to someone who knows the 14cux and how to improve it is a must before you go mad on the ACT website.

Mark_S_24

405 posts

182 months

Saturday 26th August 2017
quotequote all
Hi,

My 430 was at about 56k miles & one of the lobes on the cam was virtually non-existent.
It shunted like a mofo.
If your cars near that mileage I'd budget for a cam change.

HTH
Mark S

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
Mark_S_24 said:
Hi,

My 430 was at about 56k miles & one of the lobes on the cam was virtually non-existent.
It shunted like a mofo.
If your cars near that mileage I'd budget for a cam change.

HTH
Mark S
Mark it has only 35k on the clock.

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
jazzdude said:
I'm not too sure about the 4.3 but my 400HC is also supposedly prone to shunting compared to a standard 400.

It had had all the ACT smooth bore stuff on it when I bought it including the Decat Ypiece, carbon trumpets and still shunted. I changed all the ignition components and cleaned the Injectors, ditched the plug extenders and changed the sparks to 6s, this improved things but the shunting was still there.

Then I burned a TVR green tune map onto a EPROM chip and changed the tune resistor to 470ohm and the car is now so smooth, practically no shunting and is even quieter and more refined than ever.

I stress that this was not on a rolling road, does not have a custom map on it and cost me about £50.00 but the car is so good that I am now in two minds whether to replace the ECU this winter.

You can throw all sorts at these cars but I have since learnt that with cats and emissions mapping on the standard 14cux, dialing out shunting is very difficult as the ECU is trying to not destroy the cats with fuelling that also compromises the low speed drive ability of these cars.

Going to someone who knows the 14cux and how to improve it is a must before you go mad on the ACT website.
Far from going mad on the ACT website I am following the advice of the resepcted experts. Heath at X Works will be dumping the plug extenders and fitting new leads with socks and replacing the dizzy cap and rotor arm should that be needed. There are a couple of other little jobs he will be doing for me such as giving the engine and tune a once over. QBee is graciously going to send up his smooth bore induction that is no longer wanted and that will be fitted thus resulting in a saving and removing to old original ribbed inlet hoses which she still has at the moment.

We are not sure how sringent the testing is here on emissions and CATs so we will avoid removing or damaging them if at all possible. At least until we learn more! Maybe it will be possible to remove the CATs entirely?

Now I do like a responsive throttle and that is why I bought a TV5 throttle body for the MGF as it makes it much more responsive and that is why have been asking about teh 71mm or 72mm plenums and have even been reading about the twin plenum set up however the responses have been a rather mixed bag of answers so am even more confused that i was at the start!!!

Brithunter

Original Poster:

610 posts

94 months

Saturday 26th August 2017
quotequote all
QBee said:
I can post the bits to either of them. I know them both so can trust them. One thing about the ACT smooth bore induction kit - it comes too long, and one then cuts it to fit. Therefore mine was cut to fit my car, so may not fit yours. Happy to send it anyway, as that's the only way to find out. Personally, I would be very surprised if it sorted the shunting, unless your car has a badly kinked elephant trunk.
QBee if you could post them up to heath it would be most appreciated I am sure he will be able to get them fitted. Beign aware of the age of the original ribbed hoses replacing them with new smooth bores ones will be an improvement over all regardless of the shunting issue. I'll ask him to place the old originals in the boot and store them away once it gets here. Once he let's us know what he has fitted and used we can settle up.