http://forums.maxima.org/showthread....57#post5442057

Either to avoid the downtime for drilling them or for a VQ30 or VQ30DEK. If the intake cams are drilled to increase overlap (good for NA breathing) this could be an interesting setup in a 3.0. And they will go for cheap. Much cheaper than any aftermarket cams you can get, new or used.

Good luck on the sale. BTW retarding the cam is better for top-end breathing due to the later intake valve closing.

There is more and more maxima being tuned in montreal area.

Try to sell them on the Nissan Performance Club, they might sell faster than you think. http://www.npclub.com/bb/forumdisplay.php?f=37

But retarding the intake cam only will decrease overalp. Thats not good for NA. If you dont touch the exhaust cams, and advance intake cams only, that increases overlap.

http://www.muzzys.com/articles/lobe_centers.html

Advancing the intake and retarding the exhaust (“closing up the centers”) increases overlap and should move the power up in the RPM range, usually at the sacrifice of bottom end power. The result would be lower numerical values on both intake and exhaust lobe centers.

Retarding the intake and advancing the exhaust (“spreading the centers”) decreases overlap and should result in a wider power band at the sacrifice of some top end power.

are they from 3.5 maxima/altima or 350/G35??

if maxima i might be interested depending on price

I have done alot of reading on the subject and the most important valve event by far is the intake valve closing. That is what helps to determine the dynamic compression ratio (when the cylinder actually starts to build pressure). For a given cam grind a later valve closing event is preferred at high RPM because it takes advantage of the inertia of the intake charge that continues to fill the cylinder even as the piston moves up the bore on the compression stroke. The stock A33B and Z33 ECU's among others are in agreement with this since they advance the intake cam in the mid-range and retard it until full retard around 6k. Other VVT systems i've read about operate in the same way.

Nismo is right. You want to retard the intake cam a bit. This can be figured out be looking at the specs in the fsm. I'm going to do my setup to have 6 degree overlap.

If my memory is good...(I recently began to read JClaw's engine swap adventure)... I believe the cams came from a 2002 Altima SE.

Altima/maxima/06 and earlier G35/G35C and 350Z non-revup cams are all the same.

Are they compatible (bolt-on) with VQ30DE-K head hardware?? (cam gears, main bearing caps and shim-on-bucket type of valvetrain). I plan to swap (spring 07) DE-K heads, V-afc2, 300zx MAF, FPR with gauge, DE-K injectors with rail and VI. I already have the basic bolt-ons for the ''breathing'' but for 800$ can on a DE-K with 64,000mi, who wouldn't buy!! If they bolt right in, post your price...

First off, VQ30DE head = DE-K head. They are the same. Secondly, yes you can use these cams in a 3.0 head. All you need to do is either have them drilled to reposition the dowel pin or get adapter/spacers made. And why the 300zx MAF? Do you plan on boosting? If not, the stock MAF is fine.

I thought by ''fooling'' the informations from the ECU to the Maf would get me better fuel trims for increased MAF dimensions and readouts.But if you tell me hat the MAF is only needed for boosted applications I would enlarge the Tb instead (i.e Pathy Tb)

The same as ''the same'' bolt pattern and casting but I read that the DE-K camshafts have higher lift and a bit longer duration because this generation is equipped with the VI that breaths better at high RPM???

Different camshafts doesn't mean different heads. They both have the exact same part numbers for the heads. The DE-K intake camshafts have the same lift but less duration than the DE cams for stronger low-end so they are actually less aggressive. The exhaust cams have the same duration but slightly more lift to help top-end breathing.

Don't forget that the DEK also has better cooling than the DE.

This has nothing to do with what we're talking about.

They are from a 2003 maxima which have the same cams as the 287 HP motor, but different from the 300 HP motor.

All right. But if I only retard the intake cams, I will lose overlap. So if I retard the intake cams by 15 degrees, I need to retard the exhaust cams by at least 15 degrees.

A 15 degree retard would move the peak up about 750 RPMs if I follow the rule of thumb (2 degrees=+100 rpm).

My problem is that since the two current holes are no good, I need to drill the new holes far enough so they dont interfere. That might push the peak power a little too high for the stock engine, so I thought I would put slightly longer runners on the ITBs to bring the peak down somewhat. What do you guys think?

Overlap isn't nearly as important for making good top-end power on a VQ as you think. Late intake valve closing is.

Understood - now two things. First, how far would you go with the retard if you were building the same setup as me? And second, what effect does later intake valve closing with the same cam grind have on static compression?

I would have to know what the cam timing specs for the r-tunes are to make that decision, personally. I'll try to find them.
No affect at all. Static compression is a mechanical constant. What changes is the dynamic compression, which is lowered.

Ok I just recieved the cams today. I can easily tell by eye that the two holes are drilled different. Theres about 3 mm of difference in the location of the holes. Depending on whether its retarded or advanced, I might only need to drill one cam. Would filling the old hole with a welder work?

JClaw keep in mind you are talking about pros/cons of advance/retard on the intake, but that's for a given duration. If you are increasing the intake duration, you are already effectively creating a later intake closing.

I replied to your PM with more...

I havent recieved your message yet but the .org has been acting wierd to me lately.

Anyhow - the duration is going to remain at 262 because I am definately keeping these cams a while. So for my given duration, I have a few months to decide how I am going to drill these for the desired setup.

My dilemma is that I want to maximize top end and push the peak far up top but not TOO far that its out of the range of a stock engine with just ARP rod bolts. So I want it to peak @ 6500-6700 but not much higher. The nismo cams seem to favor a lower peak (ive seen 6200 or so) so I understand that retarding them is the way to go, but not too much.

But we really need to see a nismo cam timing chart to know exactly what we're dealing with.

I will check around for that. If any of you guys find anything, let me know.

First thing I would say we need to consider is the specs of the vq35 cams as specified in the fsm which is:

Overlap = 2 degrees
Intake lobe center line = 125 degrees ATDC
Exhaust lobe center line = 112 degrees BTDC
Lobe Seperation = 118.5 degrees
Advance = 6.5 degrees

Now we know that exhaust will remain the same but we could play with the intake cam. More than likely we would want to retard the cam to get better top end. Below is a simple calculation of determining how much overlap you will get based on a certain degree of retarding.

http://www.rbracing-rsr.com/camshaft.html

Since, there's not too much research on this for the 3.0...I went a little conservative by retarding the intake to -2 to give me a 6 degree overlap. The 6 degree overlap is the exact specs of the 3.0 cams. I'm sure you can retard it even more but like I said no one has done too much research on this and I don't have the time to be pulling the engine and doing trial and error.

Now your intake valve closing is @ 48* ABDC, 1 degree sooner than the 3.0 cam timing. I'd retard a bit more if i were in your shoes. But it's no matter because JClaw has the nismo r-tunes (which is what we're trying to find the timing specs for in the first place) not the stock 3.5's.

Im not sure if I want to retard the intake cams without doing the same to the exhaust cams. If I can fill out the old holes with a welder of course.

For example if I retard the intake cams by 5 degrees (just an example for examples sake) Id want to retard the exhaust cams by like 7 degrees. So I would be moving up the powerband a few hundred RPMs AND increasing overlap slightly.

Does anyone know what kind of metal the cams are made of and if they can take a little heat with a MIG welder?

Due to their brittleness to certain impacts I'd guess they're cast iron or steel. I've no idea really. Its just a guess. I've heard that some manufacturers use billet steel. Not sure how that effects its weldability. That said, I'd take it somewhere and have it filled with a TIG. Actually dude, we could probably do that for you.

Question somewhat relating to this. For a dead nuts OEM timed cam how far would the dowel be drilled from the original? For example: New dowel is 17X degrees in the counterclockwise direction. What would that X be? Then as the intake is retarded would X be increasing or decreasing? You guys are much better at this math than I.

On that subject does anyone have recomendation on any books that explain engine calculations well?

Also, to threadjack. Is retarding the intake cam also a good move from a boosted standpoint? Reducing overlap is desired but is retarding also desired and thus a double whamy?

If the machine shop you talked about in the PM can fill the old holes and drill new ones for a good price Ill ship the cams to you later this winter.

I'm pretty sure they don't have any welding material. You could weld it shut, or I could for that matter and then my buddy could machine it down and drill the new holes.

So, just to confirm. The filling is only for JClaw's new cams? Stock VQ35 cams do not need to be filled, just re-drilled for the VQ30DE-K?

Correct...

Yeah I may get to fill these cams TIG for cheap.

The stock 3.5 sticks are sold to TDotMax, by the way.

great sale JClaw, I have the same cams 4 sale for $250 plus shipping if anyone is interested, PM me.