Developed a bit of an oil leak a few weeks back so decided to investigate when I had some spare time. Was a bit alarmed to find a hole punced in the top of the rocker cover!!To cut a long story short, it looks like if you re-grind the cams massively like mine were and reduce the base circle down a lot then you're going to have to compensate by fitting longer valves or the rocker arms can fall off like 8 of mine did (sure the 9k rpm didn't help) No serious damage fortunately but I could have done without it to say the least!New cams/longer valves on order soon and get it fixed once I move house.Oh, also, iskey datsun 1200 valvesprings apparently work perfectly in the VH45 and give abotu 90ibs on the seat.

Anyone got a spare set of 92 rocker covers?!

what is the stock spring rate in the VH45? Be good to know if they was a common part other than the inner springs from a GTiR.Sorry to hear about your damage mate, and this is the reason I really don't like reducing the base circles of the cams, too many problems with geometry.

Would the problem have been avoided if you made larger rocker covers? Or were the arms just moving so violently that they broke of and hit the cover?

John Dixon wrote:Developed a bit of an oil leak a few weeks back so decided to investigate when I had some spare time. Was a bit alarmed to find a hole punced in the top of the rocker cover!!To cut a long story short, it looks like if you re-grind the cams massively like mine were and reduce the base circle down a lot then you're going to have to compensate by fitting longer valves or the rocker arms can fall off like 8 of mine did (sure the 9k rpm didn't help) No serious damage fortunately but I could have done without it to say the least!New cams/longer valves on order soon and get it fixed once I move house.Oh, also, iskey datsun 1200 valvesprings apparently work perfectly in the VH45 and give abotu 90ibs on the seat.

Anyone got a spare set of 92 rocker covers?!

Sorry to hear about that John! I'm sure you'll get it worked out in due time.

I have two sets of 90-93 style rocker covers I'd be more than happy to send to you. Shoot me an email... superhatch at gmail dot com.

Think the stock rate is 45ibs.The rocker went through the cover because it fell off and got whippeed round by the cam presumably! Thank god it didn't jam and snap the chains! The other ones had just fallen in around the springs and were lying there.

Cheers for the offer, email sent!I will get it fixed as soon as I move house but for now that has to take priority. Got a nice 25'x40' garage at the new place too so that will help.

I'm curious if a rocker stopper could be fabbed up for the VH like the SR uses. The SR spits them at 9k even with proper length valves and new blank cams(proper base circle).

but jared that problem goes away on SRs with solid lifters and properly shimmed valves. Ive seen countless motors with rocker arm stoppers spit them at 8000rpm, the key here is maintaining proper rocker to cam clearance, and the hydraulics will always fail at that kind of rpm.

John you could probably convert all of your lifters to solid the way we do sr20 ones and shim them internally if the clearance isnt too great because of the reduction in base circle that is, much much cheaper then getting new cams and valves and 10X better in the end.

They are converted to solid already.

If the rocker was already out, did you not notice the misfire before the oil leak?

gs14racer wrote:but jared that problem goes away on SRs with solid lifters and properly shimmed valves. Ive seen countless motors with rocker arm stoppers spit them at 8000rpm, the key here is maintaining proper rocker to cam clearance, and the hydraulics will always fail at that kind of rpm.

John you could probably convert all of your lifters to solid the way we do sr20 ones and shim them internally if the clearance isnt too great because of the reduction in base circle that is, much much cheaper then getting new cams and valves and 10X better in the end.

Dave's superstock revs out to 9000rpm on a regular basis and handles it fine on the stock HLAs!

Mettler wrote:Dave's superstock revs out to 9000rpm on a regular basis and handles it fine on the stock HLAs!

That might be an attribute of the HLA profile versus the SLA profile...

XJared wrote:If the rocker was already out, did you not notice the misfire before the oil leak?

No, because at least one inlet on each cyl was opening it ran OK and compression / leakage tests were all perfect. Does explain the low dyno though!!!

Glad to hear there was no extensive damage!

Cheers. Think I'm just going to get a set of cams and long valves off Bryan Hartley at the head shop in NZ. Proven combination then and his specs for the speedway motors fit with the powerband I'm looking for on my engine (peak tq 5.5-6k, peak power 8-8.5k).

whats the ballpark for those?

Aus450zx wrote:whats the ballpark for those?

~2k NZD for the cams and 32 valves. Not too bad really!

All parts on order. Hopefully be back on the road in a few months after I move house and stuff

Mettler wrote:Dave's superstock revs out to 9000rpm on a regular basis and handles it fine on the stock HLAs!

Any more information about this. Does his sell cams.

John Dixon wrote:All parts on order. Hopefully be back on the road in a few months after I move house and stuff

Same for this. I tried searching. I come up with information but nothing to contact. Not in the market right now. But for future reference. Converted to US currency thats about $1500 (then plus shipping and whatnot ) which isnt to bad really. Also do you have to convert over to SLA or stay HLA. Sorry for all the newbish questions.

All my bits have arrived now so once I get them fitted will have some results. You have to go to SLA for the cams I have but he does do milder ones.