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Why not just loosen the adjusting bolts and turn the crank slightly?

*Edit: Never mind, I forgot about the VCT gear on the inlet.

Edited by White GTS-T

should write up a tutorial

if yours are that far out then others may benefit too

I might do, it's quite simple if you're not afraid of a bit of maths. Just gotta make sure the equipment is setup properly and you don't disturb it after it is!

I just backed timing belt tension off a bit and rotate crank a smidge to slip the pulley off so balancer etc never had to come off for each adjustment. Think I got it in 3 adjustments.

I'd have to look yours up but on non neo standard exh is 117 and poncam is 115 so automatically there is 2 degrees. Maybe yours is a bigger difference. 7.8 degrees on intake is a whole tooth out :/

Are you checking at max lift or picking 2 measurements either side of max lift (ie .5mm before and after max lift and finding the centre mark) ?

Yeh this is probably what I will do, but still makes for tedious work. So does the VCT gear have timing marks on it like an aftermarket gear, or do you need to work it out?

I am picking a reference value on my dial indicator and noting the degree on the wheel. Then I rotate the crank forward one full rotation until the dial indicator gets back to my reference value and I note that degree value on the wheel. Then I add the ATDC value to the BTDC value and divide it by two to get the centre. So yes, how you said.

So for example, one of the equations I can remember last night was checking the final adjustment. At my reference value on the dial indicator, I had 177.5° BTDC. Then one full rotation clockwise, I had 47.5° ATDC. Then because the degree wheel I'm using is only 180 degrees, I made BTDC a negative value. So I did -177.5 + 47.5 = -130. Divide that by two to get my centre point and I get -65. Then to get it back to the other side of the degree wheel you simply add 180 which = 115.0. Spot on!

Edited by Hanaldo

Your way is probably fine. But I noted approx max lift position and zero dial gauge. Rotate around again and at .5mm before max lift record crank degrees then at .5mm after max lift record value and average the 2. Piece of cake.

There are no markings on the back of my VCT gear. I just guessed each adjustment keeping in mind the markings on exh pulley for rough values

Ah, even more tedious then :/ I don't think I'll be worrying about that last half a crank degree on the intake side! Would be nice to get it perfect, but it took several tries with the HKS gear to get right. VCT gear would take all day.

I might do, it's quite simple if you're not afraid of a bit of maths. Just gotta make sure the equipment is setup properly and you don't disturb it after it is!

Since this was your first time doing it, you should have a few tips of where you went wrong or could have done it quicker etc, and what specialty tools were needed, that's the type of info noobs like myself would be keen read.

Haha well hopefully I haven't done anything wrong yet! It is really quite simple once you understand what you're trying to do. The hardest part is actually setting up the dial indicator because of the lifter design. So need to preload the dial indicator otherwise there won't be any measurable change. Also need to make an extension rod and make sure it is parallel with the valve stem to avoid geometric errors, but then because of the tight space it's quite a challenge get to get the extension rod to sit nicely on the lifter without getting caught under the cam lobe. Not really hard, just fiddly and takes some time.

I'll certainly put a write up in my build thread of how I did it once I've finished. Have been taking pictures along the way.

+1 for all the time going into setting up the dial gauge

So your just going to skip the belt a tooth on intake Martin? I would then recheck.

Btw your stock specs are 119 in 115 ex

Edited by t_revz

So only 1 degree off Tomei specs. Doesn't explain why it's so far out.

Is 1 tooth about right? It's 7.8 crank degrees out, so bloody close to 4 cam degrees. Is that about a tooth?

Pretty sure on mine each tooth is 7.5 degrees.

You need to count crank and cam teeth to find out if its the same or search for the answer for Neo's.

I highly doubt its different.

My intake was about 6 out but only 4 degrees of adjustment left. So I skipped a tooth then rotated the opposite way to get it in the right spot. My head had been skimmed numerous times but yours seems odd its so far out. Looking forward to seeing dyno results :)

Yeh, well this coupled with the numerous air leaks being fixed as well as port matching the dump pipe and exhaust manifold, I should pick up a few kw here and there!

Yeh, well this coupled with the numerous air leaks being fixed as well as port matching the dump pipe and exhaust manifold, I should pick up a few kw here and there!

Looking at your previous results, to me it pointed out intake restriction (as in anything in the tract before the engine) with your boost being increased without detonation, but not making anymore power. that inlet cam being that far out looks like what is causing that restriction.

Looks like you will be enjoying the fruit to come.

Yeh quite possibly, I just wish I knew what caused it to be so far out. The intake cam might make sense if it's a tooth out, someone might have thought they would get gains by advancing it a tooth. But the exhaust cam? That can only be the camshaft being so far out of spec Yeh? What else would cause it to go that far out when it's not adjustable?

I'm very surprised that you guys are very surprised that cams can be ground so far off their intended lobe centres.

Anyone who built an engine in the 60s through the 90s would have expected any new or reground cam to be sufficiently far off that they'd need to degree it in properly to get it on spec. We may not be too used to that with the Jap stuff, but the reality is that it is a very common occurrence otherwise.

Yeh I suppose that's true, I guess hardly anyone would ever actually check that their poncams are dialled to what Tomei specify. I had known they can be out, but I thought by maybe a couple of degrees at most

Im basically done, just have to contact Peter from Nistune to tune it, hopefully next few weeks..

see what a G3 type A on a auto/stocky mani/ex gate/water meth does wound all the way up

cheers

darren

2w4mhc0.jpg

Edited by jet_r31
  • Like 1

Im basically done, just have to contact Peter from Nistune to tune it, hopefully next few weeks..

see what a G3 type A on a auto/stocky mani/ex gate/water meth does wound all the way up

cheers

darren

Looks schmick mate :) I like what you've done with it. Very tidy.

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