View Full Version : P38a to 4 or 4.6 that is the question
Gullible
15th June 2009, 05:53 PM
Well all the love you lot are spreading around about P38a's I'm being drawn in to the idea of getting one.
So, is the 4ltr engine enough for the weight of the vehicle or should I be looking at the 4.6 (it will be gassed so economy is not so much the issue)?
I do not intend to play with the engine just make it reliable and leave it as stock - well thats the intention at the moment:angel:
PaulP38a
15th June 2009, 11:04 PM
Can't say what they're like on gas but there are a few folks here who can. I believe the general response is that they run well on gas... vapour injenction I think is the preferred method.
What I can comment on is 4.0 vs 4.6 in my experience...
I had a rebuilt 4.6 in a 1995 HSE P38A and thought it was great.
I then changed over to a 1999 4.0 P38A and did not notice much of a power loss at all.
I believe the major difference between the two is the engine management system. Pre-99 used the Sagem GEMS system and 99-on used the Bosch Motronic (Thor) system.
I'd like to drive a post-99 4.6 for comparison.
Cheers, Paul.
POD
16th June 2009, 07:35 AM
Old petrolhead's maxim: There is no substitute for cubic inches.
willem
16th June 2009, 08:09 AM
Can't say what they're like on gas but there are a few folks here who can. I believe the general response is that they run well on gas... vapour injenction I think is the preferred method.
What I can comment on is 4.0 vs 4.6 in my experience...
I had a rebuilt 4.6 in a 1995 HSE P38A and thought it was great.
I then changed over to a 1999 4.0 P38A and did not notice much of a power loss at all.
I believe the major difference between the two is the engine management system. Pre-99 used the Sagem GEMS system and 99-on used the Bosch Motronic (Thor) system.
I'd like to drive a post-99 4.6 for comparison.
Cheers, Paul.
I have a 99 Thor 4 litre on a vapour injection LPG system and I reckon its great, but I have not driven a 4.6 Thor to compare it with. I did drive Ron's 4.6 GEMS on vapour gas injection system and the power available from his wasn't that much different from mine.
For me the 4 litre is entirely adequate, but I'm not a hoon who likes to have lots of power. Others prefer more power and will prefer the more cubes to do it with. If you need more power, then there's no substitute for cubes. Or a supercharger. Or re-chipping.... :D:D:D
Willem
Romulus
16th June 2009, 08:23 AM
I run a '96 4.6 with non vapour injected LPG, runs like a dream. Personally I cannot feel the difference between running on LPG or petrol.
I should also mention that my 4.6 was completely rebuilt.
We also own a '96 3.9 V8 Disco also on non injected LPG.
The 3.9, virtually the same as the 4.0 on the Rangie, is a tad 'slower' than the 4.6, but the difference is not that great, I find anyway.
I've not driven a vapour injected LPG so can't comment how big a difference there is between it and the standard (manifold) LPG.
LavisLane
16th June 2009, 05:19 PM
I've driven both and didn't notice a dramatic difference. I opted for the 4.6 as didn't want to be driving along wondering about the difference - silly, i know...
big guy
16th June 2009, 06:04 PM
Hi
Ihad a 3.5, 3.9, 4.0 and a 4.6
The 4.6 was a fresh motor, 9.35:1 compression with Haltech injection and gas.
That motor was a complete stonker. It blew away any standard 4 or 4.6 I pulled up next to.
The motor was built with 3.9L heads and mandrel bend exhaust.
I sold the car to a bloke I just recently spoke to again. He just had different cam and some head work done plus some different fuel system, he lost me there a bit.
Reckons its quicker than his business partners Cayenne 'S'.
We have a freeway here in SA and I use that as a performance guide for myself and it would accelerate up there very strongly right past 150km/h.
I know, I admit it, I broke the law but it sounded great up through the tunnel at full flight.
Go the 4.6 and find a high compression one.
Just my thoughts.
Happy hunting.
Oh, and the motor build cost just under $7k.
Gullible
16th June 2009, 06:22 PM
Thanks for all the input.
I think I'll keep my eye out for a post 99 THOR and not worry too much about it being a 4 or 4.6
Traco
26th June 2009, 04:47 PM
Hi
Ihad a 3.5, 3.9, 4.0 and a 4.6
The 4.6 was a fresh motor, 9.35:1 compression with Haltech injection and gas.
That motor was a complete stonker. It blew away any standard 4 or 4.6 I pulled up next to.
The motor was built with 3.9L heads and mandrel bend exhaust.
I sold the car to a bloke I just recently spoke to again. He just had different cam and some head work done plus some different fuel system, he lost me there a bit.
Reckons its quicker than his business partners Cayenne 'S'.
We have a freeway here in SA and I use that as a performance guide for myself and it would accelerate up there very strongly right past 150km/h.
I know, I admit it, I broke the law but it sounded great up through the tunnel at full flight.
Go the 4.6 and find a high compression one.
Just my thoughts.
Happy hunting.
Oh, and the motor build cost just under $7k.
Was the motor built by Triumph Rover Spares?
I see they are advertising some ex TVR 4.6 long engines currently advertised for around 6k - don't know if they're complete, rebuilt or second hand. TVR actually called the 4.6 a 4.5 although TVR Power are now selling new Coscast 4.6 replacement blocks.
Remy
26th June 2009, 07:57 PM
4.6 HSE motor with supercharger
Range Rover 4WD Heavily Modified, Lifted & Supercharged - eBay, Passenger Vehicles, Cars, Cars, Bikes, Boats. (end time 24-Jul-09 19:03:49 AEST) (http://cgi.ebay.com.au/Range-Rover-4WD-Heavily-Modified-Lifted-Supercharged_W0QQitemZ270415884046QQcmdZViewItemQQ ptZAU_Cars?hash=item3ef60aef0e&_trksid=p3286.c0.m14&_trkparms=65%3A10|66%3A2|39%3A1|240%3A1318|301%3A1 |293%3A1|294%3A50)
YouTube - Heavily Modified Range Rover
I wouldn't mind some of the bits :D:D!!!!!!!!!!!!!!!!!!!!!
big guy
27th June 2009, 11:40 AM
Block and pistons and Haltech system did come from there.
A guy in Mackay QLD build it though and wife hated it and made the pure bloke sell it and get a Statesman instead cause the wind noise was too much.
adm333
27th June 2009, 09:24 PM
Its also not just about the 4.0 or 4.6 engine, its also about the additional fruit that comes with the HSE version.
If you're going to eat cake it may as well have icing !!!!
My 4.6 HSE runs on non injected gas and goes very well.
Dave
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