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bushytas
31st October 2007, 10:44 AM
Hi all ive been looking into cams today after talking to one or two people that said my engine might be better off with a new cam.
My question is has anyone changed their cam for a High torque cam for 4wd and towing applications?
crow cams sell one that has a really nice rev range 1000
3900RPM
Anyway let me know if you have changed yours and if you have changed to a grind thats not standard and what sort of differents its made to your engine
cheers
Brendon

PhilipA
31st October 2007, 12:36 PM
Tell them they are not accurate.
Motor manufacturers spend millions on cam development.
The 4litre cam is specifically designed for that engine.

It is different to a 3.9. It has a more agressive profile.
Ask Crow how much research they have done on a 4litre Rover V8 with GEMS. I will bet it's nix nada nil .

Be careful what it does to vacuum as GEMS is a very advanced ECU, and modern ECUs do not like changed parameters.
Cam makers have profiles usually developed many years ago, and applied to many different engines.
There have been several threads on this forum in the past regarding poor results with aftermarket cams on injected engines.
IMHO, the cam is the last thing you should change after exhaust, inlet, heads, maybe chipping the ECU or piggyback. I suggest that you ask a specialist (EG Graeme Cooper, LRA,) for their opinion. I know Cooper tested many cams with 3.9's before finding one they were happy with.
Regards Philip A

Bulldog
31st October 2007, 08:00 PM
Hi. Mine's a 3.5L. I've just put a Wade camshaft in (i was doing up the engine anyway and thought i'd try it).

Works fine, sounds good, goes good. Haven't been offroad with it yet (will on the weekend). The power range is 2500-6000rpm which i think is a bit high, but i do tend to rev it high :D.

My experience probably doesn't apply to you as much since its a different engine with an ECU... ;)

GuyG
31st October 2007, 11:06 PM
My engines in the process of being rebuilt and is being fitted with a new cam, well new everything actually, what started as a leaking welsch plug. Will let you know how it goes after I get it back and its worn in a bit. Its a long story - will most probably add it to the rants section at some point

bushytas
1st November 2007, 10:35 AM
My engines in the process of being rebuilt and is being fitted with a new cam, well new everything actually, what started as a leaking welsch plug. Will let you know how it goes after I get it back and its worn in a bit. Its a long story - will most probably add it to the rants section at some point

keep us informed and if your doing the build yourself can you post pictures.
also what cam are you fitting got any spec,s for me
ive been looking at a High torque cam for 4wd and towing applications rev range from 1000 too 4000 as i seem to sit around this range when driving and out bush.
the only time its really over 4000 is when im in mud but then its sitting on the rev limiter lol rmmm rmmm rmmm love that sound its going to go rmmm pop one day

bushytas
1st November 2007, 10:39 AM
Tell them they are not accurate.
Motor manufacturers spend millions on cam development.
The 4litre cam is specifically designed for that engine.

It is different to a 3.9. It has a more agressive profile.
Ask Crow how much research they have done on a 4litre Rover V8 with GEMS. I will bet it's nix nada nil .

Be careful what it does to vacuum as GEMS is a very advanced ECU, and modern ECUs do not like changed parameters.
Cam makers have profiles usually developed many years ago, and applied to many different engines.
There have been several threads on this forum in the past regarding poor results with aftermarket cams on injected engines.
IMHO, the cam is the last thing you should change after exhaust, inlet, heads, maybe chipping the ECU or piggyback. I suggest that you ask a specialist (EG Graeme Cooper, LRA,) for their opinion. I know Cooper tested many cams with 3.9's before finding one they were happy with.
Regards Philip A


will keep it in mind thanks
the only reasion im replacing it now is its worn out so i just thought i would go for a High torque cam giving me just that bit more up hills . Living in tasmania as everyone know its full of hills and i find that the rover changes back gears a lot so i just thought it might hold on a bit more with a different cam

GuyG
1st November 2007, 11:53 AM
We started to do it ourselves, but it went very pear shaped, and now the block is being heat treated etc - what started as a head gasket is now a complete rebuild, due to previous owner/s cooking the engine to the extent that most components were warped. So now the shop is doing it - at least that way I have some warranty. Believe a torque cam is being fitted the motor is a 3.9v8 from a 1990 rangie

bushytas
1st November 2007, 09:02 PM
We started to do it ourselves, but it went very pear shaped, and now the block is being heat treated etc - what started as a head gasket is now a complete rebuild, due to previous owner/s cooking the engine to the extent that most components were warped. So now the shop is doing it - at least that way I have some warranty. Believe a torque cam is being fitted the motor is a 3.9v8 from a 1990 rangie
who made the cam do you know ?? also whats the rev range ?

justinc
1st November 2007, 09:33 PM
Hi Brendan.

Unfortunately, the P38a takes a very different cam from the other Rover V8's. The differences are at the front of the cam, and they are not interchangeable. Unless they have made the cam to specifically suit the P38a 4.0 and 4.6 engines, they won't fit. The reason is the Gems etc uses a cam angle sensor too, and this requires a different nose length and sprocket etc to the usual Rover V8 cam. Last time I cammed one, I had to fit a genuine standard cam due to the lack of availability.:mad:

I would definately check with Graeme cooper, LRA or Bruce Davis performance in Sydney as to the availability of performance cams for these etc. as it was a while ago when I did the last one.


JC

p38arover
1st November 2007, 09:48 PM
My 4.6 has a high torque 3.5 cam with the nose cut off and remachined to suit the GEMS engine. Done in-house by Bruce Davis.

Davis can convert your 4.0 to a 4.6

justinc
1st November 2007, 10:31 PM
My 4.6 has a high torque 3.5 cam with the nose cut off and remachined to suit the GEMS engine. Done in-house by Bruce Davis.

Davis can convert your 4.0 to a 4.6

:D:DThanks Ron, You da man! :D:D:D

I know where to look next time!!

JC

bushytas
2nd November 2007, 01:09 AM
:D:DThanks Ron, You da man! :D:D:D

I know where to look next time!!

JC

yeah well keep that inmind justin might be sitting in your workshop just tell me a price

bushytas
2nd November 2007, 01:14 AM
someone sent me this link cant remember who got some cool stuff but
http://www.triumphroverspares.com.au/html/motorsportparts.htm#Valvetrain

Pedro_The_Swift
2nd November 2007, 07:41 AM
If the cam is worn,,
doesnt it follow (!) the rest of the top end gear will need (must be?) replacing??


welcome back Ron!!!:D

bushytas
2nd November 2007, 10:54 AM
good question
my thoughts on it are really well my engines done 280,990 and i wouldnt mind doing the lot but everyone seems to think just do the cam ive been told the 1999 engines were a good build and the only thing that goes wrong is the cam lobes wear lifters and head gaskets need doing around 160,000 +
and apart from factory leaks they should go for ever ?
but i dont know . I myself think a petrol engine thats done over 250,000 must have a large amount of wear even if its not showing it.
mains big ends rings ect must have wear its hard for me to believe anything else.
now if it was diesel i would say its got another 200 300 tho in it but who knows
my grandfathers old HQ holden ute went arond the clock 2 times on the same engine and was still going strong on the day he past away so whos to say how or when its time apart from the big bang theory when its ****ed its ****ed

Pedro_The_Swift
2nd November 2007, 11:27 AM
as usual it comes down to value,,
how long are you gunna keep it?

for any decent length of time it might be worth your while to add new mains and rings,, plus followers.

is it a keeper????

bushytas
2nd November 2007, 11:39 AM
as usual it comes down to value,,
how long are you gunna keep it?

for any decent length of time it might be worth your while to add new mains and rings,, plus followers.

is it a keeper????

well this is right .
and as i love my rangerover and i dont want to get someone elses problems with a newer one i would rather refresh this one
ive done everything else now that goes wrong with the p38 so why sell it

justinc
2nd November 2007, 12:14 PM
Hi Brendan,

280,000km? :eek: I'd be fitting a new short 4.6 block, reco your heads and I can change your fuel map to a 4.6 setting to suit. PM if you want to go further .

JC

BigJon
2nd November 2007, 01:12 PM
for any decent length of time it might be worth your while to add new mains and rings,, plus followers.



If by followers you mean hydraulic lifters, then they MUST be replaced when the cam is done.

bushytas
2nd November 2007, 07:24 PM
Hi Brendan,

280,000km? :eek: I'd be fitting a new short 4.6 block, reco your heads and I can change your fuel map to a 4.6 setting to suit. PM if you want to go further .

JC

i was told a long block was around 6000g maybe an extra 1000 fitted also was told i could use everything i have now as its all the same and the computer would sence the extra fuel if any extra was needed is this not true ?

shaunp
2nd November 2007, 08:05 PM
Hi all ive been looking into cams today after talking to one or two people that said my engine might be better off with a new cam.
My question is has anyone changed their cam for a High torque cam for 4wd and towing applications?
crow cams sell one that has a really nice rev range 1000
3900RPM
Anyway let me know if you have changed yours and if you have changed to a grind thats not standard and what sort of differents its made to your engine
cheers
Brendon
Give Dean Tighe a Call at Tighe Cams he has some Rover grinds that work well. www.tighecams.com.au (http://www.tighecams.com.au)