Rover k 1.8 safe engine speed

[p.mole1]

I My current 1.4 K series is running with a gas flowed head, DTH throttle bodies and super sport cams with vernier timing wheels.It produces maximum power at 7500 rpm and I have set the rev limit to 7600 rpm.

I am about to acquire a 1.8 K series and will be using the SS cams, head and throttle bodies, will the 1.8 produce it's power lower down in the rev range and will the standard pistons cope with track day use?

[oilyhands]

You should expect the engine to peak around 500RPM lower. Keep your RPM below 7300 or you risk fracturing the piston ring lands

Oily

[Englishmaninwales]

There is a history of standard piston failure associated with regular rpm in excess of 7k. There are some stronger Rover pistons (Trophy 160), but might be best to consider forged pistons.

[Englishmaninwales]

Must type faster!

[p.mole1]

Thanks, I have seen pistons for sale but how do I know if they are genuine VVC 160 articles. I may fit a set of solid piper 285 cams do you think this would require forged pistons as a necessity. 

[oilyhands]

Publish a photo of the tops of the pistons and I will tell you if they are 160. Piper BP285 cams peak at around 7800, so wave goodbye to your pistons. You would require forged pistons, mods to your rods for fully floating, uprated springs that will take the lift, steel caps and mods to your follower bores to clear the taller cam lobes.

Oily

[p.mole1]

Hi Oily thanks, I have found two different pistons,a Mahle part number 710000117 and AE but I cannot see the part numbers, but the valve cutouts seem much shallower. The Mahle pistons are a wallet friendly £139 and £ 159 for the AE, I will try to get the part number.

I am trying to keep to a budget so the 285 cam is out the window.  Would you recommend using new liners or re-honing the originals? also the original SS camshafts were hydraulic tappets and I converted to solid tappets but valve train noise sounds like an old crossflow, was there a different profile SS camshaft to run with solid tappets I am worried that the opening and closing ramps might not be designed for solid tappets.

[oilyhands]

Hello,

Go back to hydraulics or you will damage the lobes.

If the liners dont exhibit ovalisation or taper then they can be glaze busted with a flex hone and reused, don't use a conventional type of honer it will be disastrous.

You could have the SS cams reground to a solid profile if you must go solid.

Check your follower clearances , it may indicate why it is so noisy.

Oily

[p.mole1]

Hi Oily,

Thanks

Some of the clearances had opened up a tad but only by 2 thou,  although No 1 exhaust valves had closed down to 8 thou.

My Janspeed head was used for motorsport and came with Piper solid followers and steel caps so the oilways have been blocked with pins, I don't think there is anyway I could remove them, any ideas ? The head came with camshafts and I was told the were 264 degree duration but it turns out the are 280 degree with 70 degrees of overlap so I can't use them either. 

Do you think it is worth persevering with the head or I should just transfer the the cams, verniers and throttle bodies onto a standard head

[oilyhands]

You could have them reprofiled to a solid version of the 1320 which is a cracking profile.

Without seeing the head I can say of it is worth keeping.

Oily

[p.mole1]

Hi Oily,

Thanks for your advice, I will be in touch next month when I get my hands on the engine and decide what condition it's in and if my wife loves me enough to have another mid life crisis. She thought a Ducati would get out of system in 2010?