RV8 - Installation of Kenne Bell Rollers - Questions

adamnreeves · Post by **adamnreeves** » Thu May 09, 2013 5:05 pm

Hey Guys,

I was lucky enough to find a set of nearly new Kenne Bell Roller Rockers at Stoneleigh. I had to fight the other punters off! I have some questions as I have no instructions. If someone has instructions I wouldn't mind a copy.

1). I have a hydraulic cam and rhoads lifters which require 60thou lash. I think I can just set to zero last and turn the adjuster a further 1.5 turns to achieve this. Don't fancy stripping down to get to the lifters to measure there.

2). Does this now mean I can increase my safe RPM limit. My cam does mean power is available upto 6,500 and I'd like to use it!!

3). Would it be worth while getting a set of those rocker shaft outrigger supports.

ian.stewart · Post by **ian.stewart** » Thu May 09, 2013 9:05 pm

I ran KBs for ages, It might be a worth a call to John Eales. He kept spares for them, RPM limit, I buzzed my rover beyond 8k on cast rockers, never broke any rockers, so believe me 6500 is not a problem, outriggers unlikely to be needed, unless you are running totally stupid springs, but then you are running hydraulics

adamnreeves · Post by **adamnreeves** » Thu May 09, 2013 10:51 pm

Thanks Ian.

Looking back to my build log:

Springs rated at 246lbs, 90lbs of seat pressure. Over the nose at maximum lift is 230lbs.

I've nothing to compare this to it is what was recommended for my cam.

kiwicar · Post by **kiwicar** » Fri May 10, 2013 9:01 am

Hi
1/ basically a sound way of doing it and dead quick, just check that the push rod just stops spinning freely, then turn the adjuster a further 60 thou. .
2/ I don't know what the timming on your cam is but those spring rates and pressures should see you to 6500, probably another 500 revs if the rest of youe valve train is reasonably light and your lifters don't pump up.
3/ As Ian says probably unnecessary.
Best regards
Mike

adamnreeves · Post by **adamnreeves** » Fri May 10, 2013 7:27 pm

Thanks Mike. I'll do this.

I've another question unfortunately. As these rockers were already installed on the shafts I thought I'd take the split pin out and check they've been installed in the correct orientation, i.e. the oil feed hole to face the push rods and it does not however I see with these rockers that the bush is split making an oil channel around the full circumference unlike the rover ones. This should mean it does not matter???

DaviesDJ · Post by **DaviesDJ** » Fri May 10, 2013 9:20 pm

Did you buy these off that bloke at the back of the indoor section, and were they on a pair of red painted heads?? He wanted 150 for those heads!! They were rubbish, so at the end I gave him 35 quid for them for porting practice and he did take it.

sidecar · Post by **sidecar** » Fri May 10, 2013 9:34 pm

They were rubbish! He wanted 300 quid for them with the rockers.

adamnreeves · Post by **adamnreeves** » Fri May 10, 2013 10:19 pm

Yep those were the ones. He wanted £350 for rockers and the heads. I told him I was not interested in the heads (I have Stage III/IV from V8D) and would he split. I offered him £250 for the rockers and he would not budge from £325 saying the heads are only worth £25 anyway. Erm, well I have been after a set of roller rockers for about 5 years so I went for it.

adamnreeves · Post by **adamnreeves** » Sat May 11, 2013 12:31 am

I have the old Rover twin SU carb type rocker covers. Ones with Rover pressed in the middle. Do you think they'll provide sufficient clearance?

Robrover · Post by **Robrover** » Sat May 11, 2013 12:45 am

Don't know about KBs, but I run Yella Terra roller rockers with the old P6 finned rocker covers that I had chromed. I bought a 1/4 inch spacer off ebay from a guy in the UK that was making them especially for this type of application. He said he did'nt sell many for Rover rocker covers as most people wanted to fit covers off American V8s to the Rover engine.

Before that I used two Felpro rocker cover gaskets glued together to get a bit more height under the covers.

Also I broke the end of one of the YT rocker shafts off at high revs and got some outrigger brackets made up to provide support.

DaviesDJ · Post by **DaviesDJ** » Sat May 11, 2013 7:24 am

Ohh roller rockers.... Would love some... Why are thy so dear and rare for rovers:-)

adamnreeves · Post by **adamnreeves** » Sat May 11, 2013 11:48 am

So I have come to adjust the rockers and finding that some are set below the lock nut which would hinder oil flow. why? well I installed chrome moly hollow HD adjustable pushrods when I first built the engine up so that I could adjust with the standard rocker gear. This is going to be a pain, adjusting the pushrods and the rocker gear, doh. Wondering though if I non adjustable HD chrome moly hollow push rods would be better as lighter, i.e. three less nuts per rod gotta be worth it? Infact what about those chevy ones with oil flow thru, erm.

Blown v8 · Post by **Blown v8** » Sat May 11, 2013 4:14 pm

adamnreeves wrote:I have the old Rover twin SU carb type rocker covers. Ones with Rover pressed in the middle. Do you think they'll provide sufficient clearance?

No !
I used to have offenhauser covers,then went to a large DJE cover, this was a far better fit,and as yet has never leaked !
I have heavy duty shafts,steel posts with outriggers with my Kenne Bells,just wished I had Perspex covers so I could see the beauty of it all ! lol

bigaldart · Post by **bigaldart** » Sun May 12, 2013 11:46 am

I notice you mention 60 thou for preload, the lower the preload the better as it allows more rev capability before pump up, with adjustable rocker arms I would aim for 20 thou. It does make a difference, of course depends on how high you want to rev it, we ended up over 7,500 rpm in the lights when we ran the 3.5 motor, Rhoades lifters and 20 thou preload.

Alan

adamnreeves · Post by **adamnreeves** » Sun May 12, 2013 5:01 pm

Not sure why Alan but I do know that Rhoads lifters instructions say set preload to 60 thous. I think I remember standard Hydraulic lifters you set between 20-40 thous. I've ran mine at 60 thous since 2010 done 6000 miles. Also had three dyno sessions. Making close to 300BHP and 300lb-ft.
I have a high lift cam, I think the highest before I need cut-outs in piston. In fact when I build the engine I went to the trouble of putting in light valve springs and using a dial guage I observed 116 thou clearance for exhaust valves and 82 for inlet valves. Minimum suggested valve before worrying is 100 and 80 respectively. Not sure how it all relates...