Monday 11th March 2002

Trumpet Blowing

New Carbon Fibre Trumpet bases for V8s

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[mark]

The inlet manifold on my 4.3 is definitly modified. Not enlarged just ported and matched.

Carbon stuff looks good though )

[2 Sheds]

Yes true to say that on the 390-450SE's& SEAC's the manifolds are modified at the bottom end, but they are still standard otherwise (38mm port size). On these cars TVR used ported heads, stage 3 in some cases.
Tim Lamont

[IPAddis]

Tim,

Do you do a carbon fibre "twin plenum" as I believe was fitted to the Rover Vitesse? If not, I presume the single carbon plenum is more efficient?

Also, what air-flow meter do you recommend? I think Mark Adams usually goes for a Jag V12?

It's next on the list after some decent brakes.

Regards,

Ian A.

>> Edited by IPAddis on Tuesday 12th March 13:40

[2 Sheds]

Yes we can now produce twin or triple throttle carbon plenums with new wide bases, i recommend the Jag or Rangerover 4.6 air meter for 5.0L engines.
Tim

[2 Sheds]

Yes we can now produce twin or triple throttle carbon plenums with new wide bases, i recommend the Jag or Rangerover 4.6 air meter for 5.0L engines.
Tim

[PetrolTed]

Piccie from Tim

[JMorgan]

I have had my trumpets shortened, have to check by how much. What gain is there on the carbon over shortened originals? Not likley to change after what has been done to mine, just curious.

[manek]

I'd also like to know if it makes much difference to a 4.0 V8 -- last time I enquired, I was told the breathing of this size of engine is pretty much OK as is.

[GreenV8S]

quote:I'd also like to know if it makes much difference to a 4.0 V8 -- last time I enquired, I was told the breathing of this size of engine is pretty much OK as is.

I got an extra 30-35 BHP on my 3.9 from stage III heads, cam and ACT induction with a Mark Adams setup afterwards.

[manek]

Hmmm, you interest me strangely.

Should be a fairly cost-effective upgrade too -- as in cheaper than taking the engine to bits and fitting new camshafts etc...

>> Edited by manek on Saturday 16th March 18:00

[GreenV8S]

quote:
Hmmm, you interest me strangely.

Should be a fairly cost-effective upgrade too -- as in cheaper than taking the engine to bits and fitting new camshafts etc...

>> Edited by manek on Saturday 16th March 18:00

Re-read the list of mods, the mods did include a camshaft change. But the bottom end was left alone.

[kerniki]

How much of a difference can these trumpets realy make, if the final diameter is stilll only 38mm? or does the trumpet effect speed up the air entering, thus more air?

Nik

[manek]

quote:

quote:
Hmmm, you interest me strangely.

Should be a fairly cost-effective upgrade too -- as in cheaper than taking the engine to bits and fitting new camshafts etc...

>> Edited by manek on Saturday 16th March 18:00

Re-read the list of mods, the mods did include a camshaft change. But the bottom end was left alone.

Oops -- missed that little 'cam' word...!

[350matt]

By flaring the trumpet / top of the port and then tapering down to the straight section, you improve the port efficiency / pumping loss and so you will flow more air, this should also effectivly shorten the port length and re-tune the engine to a higher peak power speed.

Matt