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kenf
26-02-08, 02:45 PM
Can anyone advise on a suitable fast-road cam for a standard Rover 3.9 EFi - one that will NOT require any further work to the heads or valve guides?

I'm looking for good torque primarily but would also like it to have more power further up the rev range. I want smooth idle and power from idle.

It's also going to run the existing ECU without mods until I can save enough pennies for a Megasquirt conversion.

The Crower 50230 sounds about right (kit from V8tuner is cheaper than RPI's Piper range) - does anyone have any experience of this one or other alternatives? Or is this a waste of time and should I just stick with a standard cam?

Ken :confused:

dingocooke
26-02-08, 02:58 PM
talk to sidecarbod (Pete) on here or V8 developments

tonym
26-02-08, 03:18 PM
Try Real steel web page here (http://www.realsteel.co.uk/) they do several cams for the rover, this one sticks out for the 3.9 engine

DW252 Viper Cyclone Hydraulic Camshaft Price:125.71

Designed for 3.9 Hot-Wire injection engines. OK for most applications, including automatic transmission. Worth an extra 26hp over a
std engine. If the cylinder block and cylinder head faces have not been heavily machined, and the valve guides are fitted to the correct
length, then this cam should bolt straight in. Use 3 degrees extra advance, and a "cone" style free flowing air cleaner. In dyno tests, we
obtained 26bhp extra at 5000rpm, with an extra 27ft lbs of torque at the same rpm.

Sidecarbod
26-02-08, 04:56 PM
talk to sidecarbod (Pete) on here or V8 developments

Blimey, things are getting desperate if you need my advice!

Problem is that the cams that I know about (Typhoon and Piper 285) both need mods to the heads.

I believe that the RS Hurricane does not need mods to the heads and maybe the piper 270 but you'd better check! (The 270 maybe still a bit hot if you want torque).

I don't know why but there is something that worries me about RealSteel, I have no reason to think the following but I just do. Basically I think RS are a bit too much into moving stock and inflating BHP figures more than some other suppliers. (252BHP from a 3.5 with their typhoon and 'some other mods'...yeah right!)
They also look down their noses at RV8's but will still take your money!

They obviously don't actually make the cams that they flog so who does make them? Like I said this is JMHO!

If you are going to the trouble of changing the cam you should consider a few other parts at the same time:-

1. Piper vernier timing gears and chain. (A pain to setup but the standard stuff is not particularly accurate in my experience)

2. New standard lifters, not Rhoads or other crap that claims to perform miracles even though they have no control of the oil pressure. You need to get the Rover lifters from RPI as the market has been flooded with dodgy "genuine" ones from "Bearmach". (They have not been machined properly and loads of them have failed). I think that Crane lifters are OK, well at least they don't claim anything daft!

3. I would not use shims to get the pre-load right, I tried and its impossible to get them all the same. Some people will say that its not important, its your choice!

4. The valve train geometry is not that good even with the standard cam, at max lift the rocker pad is right on the edge of the valve stem, this places side load on the valve and wears out the valve guide. Fitting rocker pedestal shims makes it worse! You need to have the bosses in the heads that the pedestal sit on machined down 1-1.5mm. (You could get the pedestals machined but they must be done all the same and accurately!)

5. The Realsteel adjustable pushrods are the way to get the pre-load right. go for 20 thou, not the 40-60 that some recommend.

6. A cam retaining plate to prevent cam walk. (The cam must have the serpentine machine mod done to it. A lot of cams have this mod)
The block may require drilling and taping to fit the plate. The bolts hit the piper timing gear but RPI will sell you a modified plate and/or bolts.


You should check for play in the rockers and the shaft, if there is any then your wasting your time sticking in a new cam without sorting this out. My under the bench scrapper as about 1.5mm of play between the rockers and the shafts!


I would have recommended V8 Developments two weeks ago, they stage III'd my heads and the work that you could see looked very good. However I have now removed all the valves and the work just behind each valve head was crap! I spent ages grinding the lower edges of the valves seats. I still 'like' V8dev, they will spend time talking to you, I was just a bit piddled off!

RPI seem like good people to deal with as does V8 Tuner. (Don't know what lifters he sells).

All of the above is JMHO and stuff that I've read.

(Des Hammills book is very good!)


Pete

robinj66
26-02-08, 05:29 PM
Speak to Paul (V8 Tuner) - you'll find his prices on these cams are very competitive. For more info look on this site http://http://www.v-8.org.uk/forum/index.php?sid=da560b641df346383ad6940cd82d4578

I've always found Paul to be very fair and not in the habit of selling you things that you don't need.

v8pete
26-02-08, 09:53 PM
When I built the 4.6, I started at first by re-using the Real Steel Hurricane that I'd had in the 3.5. Bottom end was brilliantly torquey, but the motor noticably ran out of puff towards the top end of the rev range. When the motor was rebuilt, I chose a Crane 900571 along with Crane rapid-bleed lifters. No machining required (for the 4.6 at least) - you do need to make sure that the correct valve springs are fitted & that the spring pre-load is OK. I set the lifter pre-load using shims - only a very slight adjustment was required in my case.

Engine pulls right round the clock like a dream, but even with this cam which isn't 'wild' by anyones standards, you still notice a drop off in low end torque. My advice would be to go for the max lift you can tolerate, but don't go too wild on the duration, unless you want to move power up the rev range & have a good set of exhaust headers to boot!

Pete.
BTW - I've always found Real Steel excellent!

chesterak
27-02-08, 11:12 AM
There are a number of suppliers around who will give you good advice on which cam is best for your requirements. One note of caution...I bought a cam and followers from V8Developments (their "special" grind) and it failed after about 1200 miles. After sending the bits back and their agreement that the hardening was at fault and despite promises, many letters, emails, phone calls, the promised refund has never arrived....

Just a word of caution.

oldcobber
27-02-08, 11:37 AM
Hi Ken,

I`d give Paul a ring at V8Tuner. He was very helpful when I rebuolt my engine and has lots of experience, nice bloke, quick service as well.

Bob

Sidecarbod
27-02-08, 12:30 PM
There are a number of suppliers around who will give you good advice on which cam is best for your requirements. One note of caution...I bought a cam and followers from V8Developments (their "special" grind) and it failed after about 1200 miles. After sending the bits back and their agreement that the hardening was at fault and despite promises, many letters, emails, phone calls, the promised refund has never arrived....

Just a word of caution.


I'm suprised that they just didn't say that you did not run the cam in properly!

Pete

kenf
27-02-08, 01:10 PM
Many thanks for the replies guys. Lots of useful information and opinions. I have spoken to Paul at V8 Tuner before, when I was contemplating mods to my Rover 3.5 and I found him to be knowledgable and friendly; I'll get in touch with him and probably go for the Crower 50230 kit (unless he persuades me otherwise!).

Once again, thanks for the advice and info :-D

Ken

chesterak
27-02-08, 01:55 PM
I'm suprised that they just didn't say that you did not run the cam in properly!

Pete

No, to be fair I explained how I went about the break in and their inspection/analysis, in conjunction with their supplier (Kent or Piper), confirmed the cam was at fault.

My beef is that they agreed a refund (not a total refund, by the way) but it never materialised.

There are many others out there in their line of business who will/do pay attention to customer service....

Sidecarbod
27-02-08, 02:35 PM
No, to be fair I explained how I went about the break in and their inspection/analysis, in conjunction with their supplier (Kent or Piper), confirmed the cam was at fault.

My beef is that they agreed a refund (not a total refund, by the way) but it never materialised.

There are many others out there in their line of business who will/do pay attention to customer service....


I guess that it was easy for them to agree it was their fault if they already knew that they are not going to pay up! :(

Pretty stupid of them really when you consider that you have the power of the web and this forum which is basically the loudest 'megaphone' that you'll ever find. :D

Good luck,

Pete

kenf
31-03-08, 10:17 AM
Thanks for all the advice and info.

I went for the Viper Cyclone from Real Steel in the end; rang them up, spoke to a friendly chap who was very knowledgable about the Rover V8 and gave me some good pointers on installing it and running it in. Ordered it over the phone and it arrived next day.

It's now been fitted to my replacement engine and waiting to go in, with the fueling and electrical mods to be done next.

Slowly getting there.

Ken :)

Sidecarbod
31-03-08, 10:58 AM
Thanks for all the advice and info.

I went for the Viper Cyclone from Real Steel in the end; rang them up, spoke to a friendly chap who was very knowledgable about the Rover V8 and gave me some good pointers on installing it and running it in. Ordered it over the phone and it arrived next day.

It's now been fitted to my replacement engine and waiting to go in, with the fueling and electrical mods to be done next.

Slowly getting there.

Ken :)

Good one! :D