RV8 - 3.9 cam in a 3.5 - worth doing?

alistair · Post by **alistair** » Fri Dec 04, 2009 1:23 pm

I am attempting to buy a Rover V8 car, more on this if the deal goes through, and a chap I know has a brand new factory 3.9 cam for £cheap. I have read in the past that a 3.9 cam in a 3.5 makes like 15 BHP or somesuch without any loss of drivability.

Is this true? If so I think I'll blag the cam as soon as I have a confirmation on the car.

CastleMGBV8 · Post by **CastleMGBV8** » Fri Dec 04, 2009 6:51 pm

Alistair,

Must have been pub talk, the actual gain is more like 4-6 BHP the 3.9 cam although having slightly better timing still has relatively low lift.

V8 tuner has them for approx £55.00

Kevin.

topcatcustom · Post by **topcatcustom** » Fri Dec 04, 2009 6:56 pm

Considering all the work, new set of lifters and gaskets etc to change the cam, depending on the use you may be better buying a complete 3.9.

kstrutt1 · Post by **kstrutt1** » Fri Dec 04, 2009 7:12 pm

I put one in mine and it made a noticible difference, but then my original cam, was past it's best, If the cam in the engine has done some mileage then it's probably worth changing as they are usually the first thing to go.

FYI I paid just over £100 from Island 4x4 for the cam, oem followers, chain, sprockets and gaskets (inc composite valley).

Pocket rocket · Post by **Pocket rocket** » Fri Dec 04, 2009 7:16 pm

I put one in mine - was told that it might smooth out the otherwise lumpy idle from fitting a 500 Edelbrock. Dunno how troo that was......

mgbv8 · Post by **mgbv8** » Fri Dec 04, 2009 8:12 pm

I didnt notice any difference when I stuck one in my 3500?

Quagmire · Post by **Quagmire** » Sat Dec 05, 2009 2:22 pm

I read on a forum (ORRP i think) that the 3.9 cam pushes the torque more into the middle of the rev range so you have to "drive" it more. Not sure how true that is...

I went for a standard 3.5 EFi cam in mine as i am a lazy driver and like the torque where it should be on a landrover- down low

badger · Post by **badger** » Sat Dec 05, 2009 5:34 pm

3.9 cam is a 3.5 cam advanced by 2 degrees, nothing else!
Anyone that says it produces more power is comparing it to a worn-out 3.5 cam. It moves the max power rpm down by around 200rpm and as a result gives the slightest touch more midrange torque, but that's it.

alistair · Post by **alistair** » Sat Dec 05, 2009 5:57 pm

cheers for the replies.