More Power Query

Drive it in 3rd like the manual says or dare I say it........your lobes might not be very loby

Doo said:

If I wanted a little more BHP from George (2000 V8 4.0) I would be thinking K&N panel filter and some different exhausts. But what about manifolds (or headers for them over the water)?

My question is, who's done what without going mental with cash and how has it panned out.

Fanx

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If they are still manufacturing exhaust systems for LRs then fit a Janspeed cat-back system, and you could be surprised.
I did 6 or 7 years ago and there was a noticeable difference, it must be just because the engine breathes better, on starting the engine straight after fitting the idle revs whent up to 2000 and stayed that for around two minutes or so then dropped back down to normal possibly the EFI ECU thought it better do something about it.

Anyway I'm pleased, mid-range exceleration is quicker once past 30mph, although top speed hasn't changed 110 on the flat 120mph downhill when rev limiter cuts in.

martynv8 said:

As said, a K&N will kill the MAF.
I put a Janspeed cat back system on mine & very marginal instant throttle response. With the centre box taken out it felt less a little less powered but just made lots of noise. Magnecore leads made no difference. Mine has 4.0 pistons to increase compression & a Kent 180 cam which makes it much more powered on LPG. Anything including porting heads / manifold I guess would be lost on the P38 as it's designed for torque, which is abundant in the thor 4.6 (only driven a gems 4.0 so cant compare).

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As a comparison....

The 4.0 GEMS is the one at the bottom of the punch bowl
The 4.6 GEMS is comparable with the 4.0 THOR
The 4.6 THOR Is king of the hill for the P38.

Saint.V8 said:

As a comparison....

The 4.0 GEMS is the one at the bottom of the punch bowl
The 4.6 GEMS is comparable with the 4.0 THOR
The 4.6 THOR Is king of the hill for the P38.

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I'd go with that, but only test driven a 4.0 gems so never compared a 4.0 thor to my 4.6 thor.

Thor is great for torque
As for a 4 litre gems, not worth putting lots of money in to try and match a 4.6 unless you need a new cam and you need a new exhaust. Chipping is crazy money and will make very little difference.
Trouble with more power is it is very moreish like heroin.

they are all slow compared to a l322