4.3 upgrade - what else at the same time?

[pete]

Hi all,

With over 40k on the clock of my faithful 3.6, and some depressingly suspect compression readings under investigation, I feel that a 4.3 upgrade may feature in my car's immediate future The question is, what else should I consider having done at the same time?

At the moment, the list includes just a new clutch, as my 40k mile-old original will never handle a 4.3's torque. I'd welcome suggestions from the faithful on what's worthwhile doing while the engine is out - manifolds, throttle or intake mods, anything else?

I've already got the later T350-spec chassis and a set of Gaz Golds, so the handling isn't an issue. 'S' spec discs are a possibility, although I've never had any problems with brake feel or fade. Similarly I question whether a lower diff ratio or a CR box would be needed if I had an extra lump of torque?

All suggestions happily received!

Cheers,
Pete

[Mark A S]

Traction control ,,,
Seriously, nothing I would say. As you say, with the extra torque which, IMO is the real gain with the 4.3, your not need to alter the ratio’s etc.
A de cat is something to consider.
New clutch is a good idea, anything else; I would suggest let Power check over your car and advise.
You WILL enjoy it, big time

[s5tvr]

C/R box, lightened flywheel, change of diff 3.73 / 3.91 ?

[ninetynine]

ceramic coating of manifolds will help keep heat down

[pete]

Good suggestions so far - thanks :-)

On the transmission front, I'm not going to change the diff ratio or move to a CR box until I otherwise need those bits rebuilding or refurbishing.

The lightweight flywheel is an idea; might it restore some of the quick revving nature I've grown to love with the 3.6, but will forfeit with the 4.3?

Cheers,
Pete

[Far Eastender]

I had an upgrade to a RR on my 4.0 S6, plus the following:

Lightened flywheel
New Clutch
Uprated gear box (more MPG in 5th gear)
Ceramic exhaust coating
New shocks
Bigger brakes
Upgraded ECU

[Beety]

Anyone had a 4.3 with the lightened flywheel? As its my only real worry about the 4.3, will i miss the revvy nature of the 3.6

[VARLEYHYD]

Beety said:

Anyone had a 4.3 with the lightened flywheel?

Makes a little more BHP but less torque, all in my opinion of course.
4,3 bespoke map takes it to 7,900rpm

Options to consider with rebuild:-
In order of my preference

Full major service and recomissioning of car should include geometry set up(some don't!)and usual brake & fluid changes etc.
AP Racing Clutch TVR Power have the latest type in stock, that seem to last
Replacment clutch slave cylinderRaceproved
Ceramic Coated Manifolds STR8-six do the proper stuff that lasts
Rolling road bespoke mapping
Final drive ratio gear set (only if 3.46:1)
De-cat too noisey really, unless you change the cans to ACT track cans
Quaife automatic torque biasing diff
Lightened flywheel
Powder coated cam cover

and............loads of other stuff!!

G
Hope this helps

Edited by VARLEYHYD on Wednesday 6th January 20:37

[T450t]

VARLEYHYD said:

Beety said:

Anyone had a 4.3 with the lightened flywheel?

Makes a little more BHP but less torque, all in my opinion of course.
4,3 bespoke map takes it to 7,900rpm

Options to consider with rebuild:-
In order of my preference

Full major service and recomissioning of car should include geometry set up(some don't!)and usual brake & fluid changes etc.
AP Racing Clutch TVR Power have the latest type in stock, that seem to last
Replacment clutch slave cylinderRaceproved
Ceramic Coated Manifolds STR8-six do the proper stuff that lasts
Rolling road bespoke mapping
Final drive ratio gear set (only if 3.46:1)
De-cat too noisey really, unless you change the cans to ACT track cans
Quaife automatic torque biasing diff
Lightened flywheel
Powder coated cam cover

and............loads of other stuff!!

G
Hope this helps

Edited by VARLEYHYD on Wednesday 6th January 20:37

Dont get to excited about the Quaife ATB LSD Graham.

[VARLEYHYD]

T450t said:

Dont get to excited about the Quaife ATB LSD Graham.

Have you broken yours?

Mine is way better than the Hydratrak that lets go after a bit of use.

G

[pete]

Thanks Graham - excellent suggestions.

I need to check if I've got a 3.73 or 3.46 final drive at the moment; it definitely revs over 3000rpm at a GPS 80mph so I suspect it's lower than a 3.46.

I was shying away from a decat, but I could go that route and put the original cans back on to get the noise down. My main worry then is track days; at the moment I have the luxury of just swapping from CCC cans to the originals if I want to drop 10dB to meet strict noise limits, plus I can get an MOT without any faffing about refitting the cats.

Ceramic manifolds are now firmly on the list, but not the pretty powder coated cam cover - I have a Tuscan, no-one ever gets to see what the engine looks like other than me and whoever services it

Thanks again,
Pete

[s6boy]

pete said:

..... but not the pretty powder coated cam cover - I have a Tuscan, no-one ever gets to see what the engine looks like other than me and whoever services it

Thanks again,
Pete

Time for a bonnet conversion then while the engine is out.

[yanmar]

reference diffs i think 28 mph = 3.4 / 25 mph = 3.7 both at 1000 rpm so it looks like you have a 3.7.you will not need any lower than a 3.7 with a 4.3 engine . the quaife diff is far better than the hydratrack, on track when the car slides it is much more controlable, so i would go for that, and the ceramic manifold is a good idea.. looks like i will have to go with that shortly . hope this helps and enjoy.

[geordieexpat]

Engine upgrade is it worth the time and effort?

My Sag has been changed to 19" whells, close ratio box and 3.91 diff, all made some diff to the cars handling

I love her as she is only creeping up to 25K on a 05 plate, put about 6k-7k miles on her in 2 years of ownership and been overseas for 18moths of that period so think Ive used her a bit

I am looking at the 4.3 conversion but wanted to get some feedback on what it does to the car

anything you'd care to share Graham


Rgds
Derrick

[TVR_owner]

If it ain't broke, don't fix it.

[Tvr Power]

TVR_owner said:

If it ain't broke, don't fix it.

Thats an old school saying, he who dares wins i say


Dom

[Whitey]

geordieexpat said:

I am looking at the 4.3 conversion but wanted to get some feedback on what it does to the car

Rgds
Derrick

Isn't it supposed to make it go quicker?

I would get a dyno run done at Power or Surrey RR and see how strong your current engine is then find out how much more you would get with the 4.3.

[Don1]

A person on here who knows a bit about these things, suggested that the 3.7 diff would be better with the 4.3... Just an FYI.

[TVR_owner]

Tvr Power said:

TVR_owner said:

If it ain't broke, don't fix it.

Thats an old school saying


Dom

But still every bit as valid today as it was in the olden days

[Mark A S]

geordieexpat said:

Engine upgrade is it worth the time and effort?
I am looking at the 4.3 conversion but wanted to get some feedback on what it does to the car
Rgds
Derrick

5 years unlimited mileage warranty, another 50 bhp or so depending on final spec. Most noticeable difference though, is the torque up 70 to 90 Ibs of the stuff.
This makes a Very nice difference to the car, especially for real world driving.
What it does to the car ?,
rips the st out of the rear tyres,
traction control with your right foot is activated greatly,
overtaking in 4th and 5th now a lot easier
Massive smiles
Lighter wallet
Better MPG !
Makes the horizon come up much quicker
And,,,,,,,,,,,,,,,,,,,,,, peace of mind.