WHICH CAM

[s3c chris]

As a new owner of a 400 Chimaera I'd like to ask for some advice please?
I was aware that the tappets were sounding a little noisy and despite the low 49k miles a camshaft change would be one of the jobs to be done.
But which cam should be used?
I am not interested in upping the power, I just want a smooth engine that produces power similar to the factory quoted 240bhp.
It has been suggested a TVR Power cam kit would be suitable. Will the standard gears be ok and should they be renewed also?
Your thoughts would be appreciated, cam choice seems a minefield!
Regards Chris.

[SILICONEKID345HP]

s3c chris said:

As a new owner of a 400 Chimaera I'd like to ask for some advice please?
I was aware that the tappets were sounding a little noisy and despite the low 49k miles a camshaft change would be one of the jobs to be done.
But which cam should be used?
I am not interested in upping the power, I just want a smooth engine that produces power similar to the factory quoted 240bhp.
It has been suggested a TVR Power cam kit would be suitable. Will the standard gears be ok and should they be renewed also?
Your thoughts would be appreciated, cam choice seems a minefield!
Regards Chris.

Check the exhaust manifolds .

[zed4]

I have the V8D MC1 cam and it's great. It's so smooth and drives very well, no shunting and very easy to drive at slow speeds. I also replaced the trumpets with carbon superflare trumpets and added the smoothbore induction kit. Once it was all fitted my car was running 210hp at the wheels, 240hp at the flywheel. I'm very happy with it.

[phazed]

Meaning that what can sound mechanical can be an exhaust leak.

Check carefully with a length of hose, (with one end in your ear ).

[QBee]

phazed said:

Meaning that what can sound mechanical can be an exhaust leak.

Check carefully with a length of hose, (with one end in your ear ).

What has already been said twice.

Before you look at changing a cam, unless a TVR expert has driven and listened to the car and confirmed you have a cam issue, do as described above. The length of pipe trick in detail is to get a length of rubber hose, say off your gas barbecue, stick one end in your lug hole, and with the engine idling point the other end close to, but not touching, the exhaust manifold, moving it around until you have listened to the whole of both manifolds. If there is a leak the sound will suddenly be a lot louder.

The tappety noise is often actually a leak at the exhaust manifold, either from the gaskets or, more often, from where the 4 pipes go into one. The fix in either case is relatively cheap. The 4>1 leak is a case of removing the manifolds, cutting them open and welding up the fault, then accurately re-welding the manifolds and re-fitting them. Costs £100 to £200. Before you do it, have a discussion about removing the pre-cats, as it is a bloody sight easier to do with the manifolds cut open.

[ChilliWhizz]

s3c chris said:

As a new owner of a 400 Chimaera I'd like to ask for some advice please?
I was aware that the tappets were sounding a little noisy and despite the low 49k miles a camshaft change would be one of the jobs to be done.
But which cam should be used?
I am not interested in upping the power, I just want a smooth engine that produces power similar to the factory quoted 240bhp.
It has been suggested a TVR Power cam kit would be suitable. Will the standard gears be ok and should they be renewed also?
Your thoughts would be appreciated, cam choice seems a minefield!
Regards Chris.

Good advice above about exhaust manifolds...

Regarding cam choice, I'd suggest talking to someone such as Rob at V8 Developments. You'll get solid advice based on your needs... (As I'm sure you will from TVR Power).

V8D are on 01775 750000

Chilli

[blitzracing]

MC1- dogs nuts on the 4 ltr engine.

[Chuffmeister]

I've got a standard 218. It doesn't produce the greatest BHP figures, but gives a relatively smooth drive. I drove a 500 with a stealth recently and it has more umph at the top end of the rev range, but seems to have less mid range. I guess as others have said in the past, it depends whether or not you're looking for a fast road cam or one for the track and how you will most use the power.

[QBee]

Chuffmeister said:

I've got a standard 218. It doesn't produce the greatest BHP figures, but gives a relatively smooth drive. I drove a 500 with a stealth recently and it has more umph at the top end of the rev range, but seems to have less mid range. I guess as others have said in the past, it depends whether or not you're looking for a fast road cam or one for the track and how you will most use the power.

Isn't that weird? My 500 with stealth cam has fantastic torque right across the useable rev range (over 300 torques from 2000 to 5500 RPM), so much so that I am known for being surprisingly quick on track due to the car pulling out of corners so well despite, at a mere 300, having less BHP than some of my willy-waving friends.

[ChilliWhizz]

Stands by and waits eagerly for QBee's willy waving mates to arrive.............

Edited by ChilliWhizz on Tuesday 1st July 14:15

[phazed]

Can someone point me out the willy waving icon, I think the mods have moved it

Right. Just do all the mods to the engine that good money can afford and it'll go faster.

or

Buy my well sorted 4.6 and save yourself a lot of grief!

[QBee]

phazed said:

................and save yourself a lot of grief!

...and you wouldn't want to own a grief on the Chim forums, would you?

[TVR Beaver]

does this work Peter :-



Got to say my Stealth was the same.. nothing until 4500 ish?.... strange why some are good and some not??

Edited by TVR Beaver on Tuesday 1st July 17:11

[phazed]

The cam on my 4.6 is very linear.

It was modelled on the Real Steel Tornado cam, ('cept they couldn't get stock so Kent did me a looky likey).

Of course you have to tie in a good cam with all the other mods to make it really worthwhile.

If yours didn't have much below 4.5k revs then maybe the cam timing was out.

[l6rth]

blitzracing said:

MC1- dogs nuts on the 4 ltr engine.

I have changed trumpets and elbow and small considering mc1 fit in the winter, is there anything else I should add to get the best from the cam?

[Chuffmeister]

QBee said:

Isn't that weird? My 500 with stealth cam has fantastic torque right across the useable rev range (over 300 torques from 2000 to 5500 RPM), so much so that I am known for being surprisingly quick on track due to the car pulling out of corners so well despite, at a mere 300, having less BHP than some of my willy-waving friends.

It just felt different from my own. Definitely more top end. 2nd and 3rd didn't feel as aggressive in the mid-range. Saying that, your engine is a purpose built V8D, so has probably been set-up to make the most of the cam. Also, how much that power etc. is down to the V8D heads and good compression? Not everything is down to the cam!

Edited by Chuffmeister on Tuesday 1st July 18:49

[QBee]

Chuffmeister said:

QBee said:

Isn't that weird? My 500 with stealth cam has fantastic torque right across the useable rev range (over 300 torques from 2000 to 5500 RPM), so much so that I am known for being surprisingly quick on track due to the car pulling out of corners so well despite, at a mere 300, having less BHP than some of my willy-waving friends.

It just felt different from my own. Definitely more top end. 2nd and 3rd didn't feel as aggressive in the mid-range. Saying that, your engine is a purpose built V8D, so has probably been set-up to make the most of the cam. Also, how much that power etc. is down to the V8D heads and good compression? Not everything is down to the cam!

Edited by Chuffmeister on Tuesday 1st July 18:49

Good comments. Mine is a V8D 500, with a lightened flywheel, stage 3 heads, fully ported, improved induction, bigger injectors etc, 10:1 compression and the stealth cam. It does rev well to 6000 rpm, but the torque out of tight corners without changing down to second gear is remarkable. Like Peter's car, the torque number exceeds the bhp number by a nice margin, making it a very driveable car. It was specifically set up to be a track day car and fast road car, but it runs great whatever I am doing, even around town.

[Mr Nordic]

Hi I had the same problem with 73k on the clock of my 400.

I spent ages trying to decide which cam to fit and in the end I replaced mine with the TVR 51 cam with vernier sprocket from Dom at TVR Power and set up as per their advice.

The car drives exactly as they predicted, really nice, smooth, no shunting and is much more responsive than the worn item.

I realised that I wanted yo enjoy the drivability of the v8 and not to compromise this for a few horse power.

It's a very personal choice and this worked for me.

[ChilliWhizz]

Hmmm, the vast majority of RV8's (where RR's are posted - even the TVR figures..) do have higher torque than BHP numbers, in fact my BGT V8 did. I don't think that fact in itself (higher torque figure) makes a car more driveable than one that has a higher bhp figure... after all the max bhp figure is way up the rev range.. And of course It depends on what you mean by driveability (and your particular driving style) which can be/is a very subjective thing... My cam is a tad more 'lairy' than a stealth, and my bhp figure is higher than my torque figure however the car is well set up, has oodles of torque, and pulls cleanly from around 1400 - 1500 rpm in fifth, making good, smooth, and rather rapid progress However, from 4k to 6k rpm its just a wall of power

I'll be exploring the wall more fully when I get some sticky tires in September

[QBee]

Love this forum. We all love our cars, and we get them so they suit our driving style. And we are all different.
When you are back in the country Chilli, give me a buzz and let's book a session at your local track.