Carbon Fibre Plenum

[paulu]

Anyone fitted one? what do you think?

[q405mb]

who makes them?

[david beer]

ACT make them. But i think you need the rest of the bits to see any improvement.

[kerniki]

Just had Plenum / larger throttle bodies fitted, along with Mark Adams chip to suit afore mentioned goodies, definateley smoother and more power, as a rolling road sesion before (230bhp at the wheels) and after (245 at the wheels) has prooved, that equates to approx 20-25 BHP at the flywheel apparently, I personaly don't think that the £ involved is worth the the amount of extra power produced, having said that, the Rover V8 is renowned for being costly to get extra BHP out of, hope this helps, Nik.

PS. Induction sounds great though!

[q405mb]

Kerniki,

Have you compared fuel consumption now to before the plenum/bits conversion?

Harrigan

[kerniki]

quote:
Kerniki,

Have you compared fuel consumption now to before the plenum/bits conversion?

Harrigan

I must admit, no. It's never realy been a priority Harrigan, having said that, the engine is so much smoother it must be running more efficiently and therefore off set the extra air intake / fuel intake, i'm no expert (no doubt someone will guide on this) but it makes sense. Hope this helps.

Nik

[shpub]

Basically....


More power needs more fuel... The efficiency is by and large the same for any correctly setup engine.

Fuel consumption costs pale into insignificance compared to the very large wedge you need for this type of work. Budget £3-4000 pounds and that is based on an alloy plenum. Previous owner did this to my Griff and I've got the bills.

You also need so form of brkae upgrade as well to match the grunt.

[2 Sheds]

quote:

Fuel consumption costs pale into insignificance compared to the very large wedge you need for this type of work. Budget £3-4000 pounds and that is based on an alloy plenum. Previous owner did this to my Griff and I've got the bills.

You also need so form of brkae upgrade as well to match the grunt.

[2 Sheds]

quote:

Fuel consumption costs pale into insignificance compared to the very large wedge you need for this type of work. Budget £3-4000 pounds and that is based on an alloy plenum. Previous owner did this to my Griff and I've got the bills.

You also need so form of brkae upgrade as well to match the grunt.

Steve I don't know what was done to your car to cost the previous owner £3-4,000 it must have been more than just induction, i assume engine rebuilding etc ?
Alloy induction inc chip & rolling road etc (5 litre) circa £1350. Carbon fibre £1750 (including VAT)
sometimes injectors need cleaning (+£200ish)uprated cam +£700 ish, Thats about all you should need unless your engine is "shagged" or there are ECU / ignition faults etc.

[q405mb]

Hmmm, yes, after posting my fuel consumption question, I thought it was a bit of a daft thing to ask... It is a rumbly V8 after all

The relativity of consumption costs to the cost of upgrades is relevant, thanks for pointing that out Steve. If you have the wedge for the car AND the upgrade, who cares about a bit more spent on fuel?

H

[JonRB]

2 Sheds - of course Steve has had more than that done! You wouldn't expect the owner of the 520 wedge to do things by halves, would you?

[shpub]

quote:
Steve I don't know what was done to your car to cost the previous owner £3-4,000 it must have been more than just induction, i assume engine rebuilding etc ?

Yes Tim you're right, it had a slightly hotter cam fitted with lobes instead of circles, V12 Jag air flow meter and a set up session or two and the bill came to around 2700 for the engine bits and work and around another 700 for the chipping RR time and set up etc. I must admit I tend to treat this as a complete package. Some do it for cheaper and some do it for less and includes all the fitting and so on. It also included VAT.

If you add up the prices you quoted then it starts getting into the 3 grand region so I don't think there is that much difference and there is always something extra to take into account.

If you are going to change the induction, no point in spoiling the ship for the sake of all the other goodies... especially the air flow meter!

Given the car a genuine 300 bhp which Mark reckons he can squeeze a little more out of. It was around 260 ish originally. Unless you want to spend really big bucks, the induction/rechip and possibly cam change is the way to go. Maybe the costing alternative is to budget about £100-£150 per extra bhp.

Steve

[shpub]

quote:
2 Sheds - of course Steve has had more than that done! You wouldn't expect the owner of the 520 wedge to do things by halves, would you?

Tim knows all about the 520 and has been most helpful and supportive of the 520. It had the ACT plenum on it to start with. At the time I wanted the next power fix, Tim couldn't supply the triple (he can now and was showing them at Duxford) and the JED one it had now was originally intended to go on the engine so it was the only real choice for me at the time.

Tim and I regularly compare notes as the 520 is really pushing the envelope...

Steve

[JonRB]

quote:Tim and I regularly compare notes as the 520 is really pushing the envelope.

Ooops, sorry - I should have guessed that from Tim's profile really.

[2 Sheds]

Thanks Steve, I think the most Important thing to stress is that Upgrades on a 5L cost more than most people realise, Our comments should help people to "go in " with their eyes open, David was correct, if you just fit a carbon plenum you will actually lose power as the engine will run weaker. (this doesn't apply to all models) you must think in terms of a package,
Start at £1750 inc fitting and VAT (induction only) £2100 with an air flow meter upgrade. but as steve says why stop there ? Its easy to get Sucked in to a never ending project, Power corrupts, be warned !