The V8 Owners Forum -

And is that sufficient for the cam/lifter combo you are using ?

Are they just singles ?

The thing is that this engine revved to 6k and more with the standard rockers, they were then changed for a set of rollers rockers and now it won't rev.

I considered buying the same set at Stoneleigh, glad ...

Rope method I had heard of actually. Even worse on the back in a Westfield the engine is even lower. Thanks for your help.

Yes, I think you must be right steve. I think it ought to be possible to change springs it situ. Just get each piston in turn at TDC so valves do not drop. Then use an older rocker shaft and use a tool to prise the springs down.

stevieturbo wrote:And is that sufficient for the cam/lifter combo you are using ?

Are they just singles ?

They are singles. I just checked the pipercam site and they recommend VSSV8 springs which say 246rate. I presume this means 246lbs at full lift.

Valve springs have 75lbs seat pressure and 200lbs at a lift of 12.7mm. They were sourced from real steel.

The springs have been in there since September 2009 and I have done a total of 6000 miles about 2000 miles on track, 4000 on road.

Picture from my build diary:
http://www.westfield-build.com ...

Went out tonight to try after the adjusting preload to 20thou.
Cannot find my SD card for the data logging but the tacho is confirming I can only reach 5,700RPM now. A little upset to say the least. Spent hundreds of pounds on this conversion. I am seriously thinking of putting it back to standard.

Hi
They could well be SBC rockers "repurposed" for the rover engine, in which case they very well could be 1.5-1.55:1 ratio.
Best regards
Mike

Noooo, I don't want to be hearing that!

Yes I can adjust the push rod or rocker. I adjusted the rockers tonight. The thread pitch means one turn = 40 ...

I measured the ratio as best as I can whilst installed and I make it 1.55 however just 1mm error means it is 1.45 to 1.59 I think. So I am thinking these are 1.60.

Oh, the valve springs by the way have 75lbs seat pressure and 200lbs at a lift of 12.7mm which if I remember correctly is pretty much on spec to what my cam manufacture says to use with the cam.

I'd drop the pre-load down to 20-25 thou!

If you are using adjustable pushrods just tweak them up so that is no preload AND no play then turn the adjuster 4 'flats' of the nut then lock them off at that.

They are adjustable push rods. I spent an awful long time adjusting them and the rocker arm ...

Thanks for the replies. I did this as an upgrade! :D Anyway I do mean pre-load. Heavier possibly when I think about it, the OEM ones are ali and this are squarer and have adjusters built it so could be. Ironically I thought I would be able to increase RPM as my max power could be around 6200RPM. I ...

So I have installed my roller rockers and increased my RPM limit from 6000 to 6500. However I am a little disappointed.

Previously on the standard rockers I could accelerate right up the 6000 without any sign of let up. Now I accelerate and power seems to be down and starts backing off around 5600 ...

Blown v8 wrote:I do have cut outs, but no pics,as they were installed before camera phones were popular ! lol

Yep thought you would. I will probably leave my solid lifters and cam upgrade until I've put some nice forged pistons in.

ian.stewart wrote:I hope the bolts are necked to allow for oilflow up to the rocker arms ??

They were. Good call though I shall check the dims.

I too dumped the springs and went with spacers, I ground the bolt heads down aswell!
I run solid lifters on mine

More by luck than judgement I bought some titanium bolts and they are only 13mm heads and have plenty of clearance.

Solid lifters. I think eventually I will go this route. Do you ...