Tappet Noise I think

[Chryco Psycho]

if you have a double spring you should be fine Lunati can provide nessisary spring specs if you want to test the springs
 the rockers & pushrods should handle the load ok but a stiffer pushrod wouldn't hurt
 Cloyes or a JP billet timing chain will work for you , the JP unit has 7 keyways to dial the cam in

[dlrogers]

Awesome - thanks

[Chryco Psycho]

go back to CHAT , i AM IN THERE

[moper]

A couple notes here:
The Lunatis require a dual spring assembly. That is NOT a spring with a flat wound spring inside it. If that is what you have you need to replace the springs and more than liekly will need to cut the heads to fit them. This is kind of a moot point because note number two is you cannot expect to get the crap out of the engine with the oil filter. The cam and lifter material is iron and it comes of in all that glitter you saw. If you saw giltter on top of the spring retainers, it has gotten everywhere in the engine. Between the rings and cylinder, the piston skirts, the bearings (all of them), the valve guides, etc. It's like filling the engine with sand. The only way to properly repair this is to pull the eninge, strip it down to bare block (means pulling out the cam bearings and all oil plugs) and start cleaning everything. Hopefully there is no any big damage but I'd replcae rings, the bearings will be imbeded with iron so replace them, new cam bearings, and reassemble. While you're doing that, have teh heads disassemble and the seats and guides cut for dual springs, then put it together with the outer springs only. Break in the enw cam, and then add the inner springs. Sorry but thats how it needs to happen in my opinion.

[dlrogers]

Thanks for the advice moper, I have to say I'm slightly depressed because I've just got the new gear - ready to install actually. I have the cam figures back from an engine shop that builds race engines for the NZ Touring Cars (V8s) circuit. They told me the cam with the wiped lobe was a higher performance cam than the race cars and the Lunati choice so I'm fairly comfortable with the valve spring setup as it is, but I will check that before I reassemble. I was told that it is a bit of a hassle, but not a bad idea to take one spring out for the first few hours of running just to help things settle in so I may do that.

[moper]

As long as you have doubles take the inners out. I'm much more concerned about the iron dust that has been ran thru that engine. Only pressurized oil is filtered. Which means assuming the filter caught it and didnt plug and go into bypass the bearings should be ok. But the thrust bearing, piston skirts, pins, bores, rings, valve guides... not to mention the oil pickup and pump that had to move the pre-filtered oil... those are all splash oiled so they got exposed to the iron dust. If the filter DID go into bypass at all the bearings are all questionable too. realistically a poor roll of the dice at this time will only cost you a little more money and the same time later if there is damage present.

[cwestra]

I'd be curious to know what the spring rate and seat pressure is with the springs you have in there now.  With the "radical" cam that was in it and the excessive wearing you saw as a result of it, you may have a spring with a lot more pressure than you should have, particularly since you're going with a milder cam.  Moper or CP are certainly the authority here, though.  I'd be interested to know what they think.  After all that work, you'd hate to have it happen again due to too much spring force.

[moper]

Is there any way to post the cam card for the cam that was installed? There should be a record of a part number somewhere.

[dlrogers]

I've just got back from the city with the new cam and timing set - I decided to order the matching lifters and spring sets but will have to wait a few weeks for them to ship in from the States. While down there I visited my uncle - he's the one who builds the race engines for various crews. We mapped the new lunati against the old cam for interest's sake and discovered they are very similar- there are only a few thou " difference in lift and the curves on the print out almost sat on top of one another. He was of the opinion that the damage most likely began the moment the engine was fired up at the previous cam instal and that we'd be ok with a clean up and fresh oil etc. Of interest was his comment regarding lunati - he said cam manufacturers didn't like it when motor shops had the technology to measure cams because it can be found out whether the advertised specs are accurate or not - with the lunati I got he was impressed because there was only 4 thou " difference between advertised lift and actual, which he said was pretty good. Anyway, he's shown me how to set timing up with a dial gauge so as soon as I have things as clean as I can get them I'll set it up. Hey CP, I got the JP timing set 

[dlrogers]

Hi CP - I'm taking the sump off and can see I'll need to take the centre link off first. Do I need a separator to separate the joints? It seems to be holding on pretty tight.

[Chryco Psycho]

I just hit it hard with a hammer , the rod ends will usually pop apart

[dlrogers]

Thanks for that

[dlrogers]

I'm gonna have to take the heads off to change the springs etc aren't I?  - is there a recommended head gasket for the 906 heads? I'd kinda like to maximise the compression ratio so I guess not too thick. I suppose I'll get to find TDC a lot easier this way. I'm still waiting for the Lunati springs to arrive but I've been given a scare by someone who is worried that they are not US made - is that true?? I don't want the inferior ones that are not made in the USA.

[Chryco Psycho]

you can change the springs easily with a spring compresser from Mancini racing & either a piece of soft rope fed in through the spark plug hole & the pistion raised to hold th evalves closed or using compressed air to hold them closed

[dlrogers]

Ok, parts finally arrived from your side of the world - I've got new lifters, matching springs, retainers and locks. I'm keeping the orginal rods. Do you think I need to check preload if the lifters are the same height as the previous ones? I'll do a final clean tomorrow morning and then begin putting everything back together again... no doubt I'll have heaps of questions.