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Haha Yeh well that's what I was doing for the last two days, moving the gear backwards and forwards and not getting anywhere :/ all sorted now, time to out it all back together. I somehow don't think my car will be very driveable until I get a tune now though :(

Dont know if I missed something but why are your poncams needing to be dialled in? There drop in.

Dont know if I missed something but why are your poncams needing to be dialled in? There drop in.

Yeh. Turns out they're not as accurate as Tomei say they are.

Keen on results for the SLSS2 results stao, if it does what I hope it will probably end up on my SR.

Martin you have me worried about my own poncams.. while I am 100% certain the cams are at least dialed where they are meant to be, it doesnt mean the lobe centre isnt whack like yours.

Le sigh, more work.

 

Yeh. Turns out they're not as accurate as Tomei say they are.

 

I Checked mine the other day (just lined up with timing marks and marks on gates belts) and its pretty much perfect. The minor amount it is out is probably due to the block looking like it has had a bit taken off it in the past, not enough worth worrying about anyway

Dont know if I missed something but why are your poncams needing to be dialled in? There drop in.

Skimming the head or block or different thickness head gasket also throws it off.

Dont you just set the cams to the stock mark, or are we saying the stock marks aren't accurate?

Its not the stock marks that are the issue, it's that Tomei didn't get the cams quite perfect.

 

 

I Checked mine the other day (just lined up with timing marks and marks on gates belts) and its pretty much perfect. The minor amount it is out is probably due to the block looking like it has had a bit taken off it in the past, not enough worth worrying about anyway

You're not gonna see anything by lining up the stock marks, my timing marks were in the right place too. You need to actually check with a dial indicator that the lobe centreline is in the right spot according to the cam specs that Tomei supply with the cams. The stock timing marks just mean the gear is in the right place, it doesn't mean that Tomei got the cam in the right place.

Yuh, new/reground cams are not often 100% correct. It isn't a problem for most people fitting these drop ins, because they usually end up getting fiddled by the tuner looking for whatever power characteristic is desired (ie max power outright, or earlier spool, whatever), and so they get adjusted to be "right" for that job regardless of how well they align with the stock gears.

Keen on results for the SLSS2 results stao, if it does what I hope it will probably end up on my SR. Martin you have me worried about my own poncams.. while I am 100% certain the cams are at least dialed where they are meant to be, it doesnt mean the lobe centre isnt whack like yours. Le sigh, more work.

Well if you fit the cams and you get the expected gains from it then there probably fine.

 

Its not the stock marks that are the issue, it's that Tomei didn't get the cams quite perfect.

You're not gonna see anything by lining up the stock marks, my timing marks were in the right place too. You need to actually check with a dial indicator that the lobe centreline is in the right spot according to the cam specs that Tomei supply with the cams. The stock timing marks just mean the gear is in the right place, it doesn't mean that Tomei got the cam in the right place.

 

Yeah I meant I lined it all up to the timing marks and then checked and everything was pretty spot on

 

Well if you fit the cams and you get the expected gains from it then there probably fine.

 

In my case it was a fresh motor and I had nothing to compare it to. The tuner reckons its doing what it should but you never know, its possible there is more to be had. Despite the fact they are zerod to factory spec off the gears/chain and there is ZERO vacuum leaks in my setup I still lost a fair bit of idle vacuum going to these cams, and they are only 256s.

Your motor is completely stock right? Never had the head off? If so they might be ok.

They are meant to be a full drop in... I think Trev and Martin have suffered because their motors have been apart in the past, with surfaces skimmed. Like mine also. It doesnt mean Tomei get the lobe centre spot on though... It might still be off, which is why they advertise specs so we can work it out.

Your motor is completely stock right? Never had the head off? If so they might be ok. They are meant to be a full drop in... I think Trev and Martin have suffered because their motors have been apart in the past, with surfaces skimmed. Like mine also. It doesnt mean Tomei get the lobe centre spot on though... It might still be off, which is why they advertise specs so we can work it out.

Yep never been apart! So i can see what you are saying :) carry on.....................

The idea is that because your motor has never been apart the decks are at factory height. Being factory height means that when the belt is installed properly (all markings used, correct position etc) the cams will sit exactly where Nissan intended them to (assuming they are stock).

Once you dismantle the motor things start to change. For myself both the head and block were warped, and I had to have both decked flat. This meant that the cams ended up being closer to the crank, so the non tensioned side of the motor had extra slack which pulled the cams back. Combine the new shorter distance between cams and crank with the new MLS headgasket and the distance was way off what it normally would be.

So my thinking for yourself is that the motor is still within factory parameters and wont experience these problems. HOWEVER, this is only assuming that the cams are spot on. The cam supplier normally advertises the specs so the end user can check and confirm that the cams are at true centre (where the manufacturer intended them to be).

The poncams are intended to be a complete drop in, and according to unigroup they did exactly that in my car... Yet I am still curious as to HOW spot on the grind is compared to what the specs say. I know the front of my cams meet the correct position/markers when the motor is at TDC, so I am just trusting Tomei from there. Which is pretty much the same position you are in.

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