Still learning about this stuff, I only get the basics. I just know I want to optimize duration of valves being open, and lift for maximum airflow time and area without encountering:
1) too much lift causing valve float or valve-piston contact from excessive lift
2) too much duration causing weird airflow where exhaust/intake flow goes the wrong way possibly

Obviously the most lift I can get away with before I see piston-valve clearance issues at TDC is good. I'm getting like 50/50 information on 272 vs 264 duration depending on who I talk to though. So 264 duration is optimal given the rev range I am looking at (1500-7000RPM)? I wouldn't mind losing some low end if it meant in the future I could just build the bottom end and rev to 8k for some extra power. I'm thinking higher RPM gives opportunity for lower gearing for even more acceleration. This is a "half-***" build I know, so if I decide to finish the bottom half in the future, it would be nice to see more gains from bigger cams.

 

Something new you can learn about is duration at .050. This is important. The JWT C2 behaves more like a tweener cam(264-272) in this spec. I'm going to make your head hurt by the time this thread dies!

 

Called up JWT about cams, told them my application (NA built top-end only, street w/ occassional track/road course/autox 7000rpm). Tech said C8 cam would be fine for that application, and has no valve-piston clearance issues (other manufacturers couldn't guarantee this as they are likely just not as familiar with the VQ engine, so this was a big selling point for me - simplicity & reliability of install). So JWT C8's * springs/shim kit should be in next week sometime, and hopefully I'll get them in the car that weekend or early the next week.

Now I have to email uprev and have them send me a new base tune for the new cams. Also, Ferrea kit for sale in engine classifieds now... $1120.

Just called Ferrea, I can use their valve seals with the OEM valves. Stem diameter is the same size on Ferre valves and OEM, head diameter is the only difference.

Any other parts I should replace besides seals while I'm there?
http://www.courtesyparts.com/350z-pa...5_716_725.html

 

I think you did the right thing going all JWT, I really enjoyed mine, I just wish I had made power at a higher RPM...

 

So, I pick up the heads from the machine shop after they replaced valve seals, installed with JWT spring/shim kit, and resurfaced/cleaned them up. I didn't notice this until I went to drop them off at the mechanic doing my rebuild (he pointed it out to me):



You can see the one line made by whatever machine/cutting tool is a bit deeper, and you can actually feel it/catch your fingernail running across it one direction like a tiny stair step. I don't know how to measure that, but am taking it back to the machine shop to have both sides resurfaced again (to keep compression equal on both sides).

At this point, I'm starting to worry about valve-piston clearance issues cropping up if too much is cut off the bottom of the heads. JWT says there's no valve-piston clearance issues with the C8 cams and OEM pistons, but I don't know how much clearance there is to work with when resurfacing heads. Going to call them tomorrow and ask, then go tell the guy to re-redeck the heads. What you experts out there think?

Anyone know OEM deck height? NVM, found the FSM http://www.nicoclub.com/FSM under EM.pdf

Edit: Shop resurfaced it, apparently a shaving of aluminum caught on the blade and dug a little tiny trench. He didn't think it would cause a problem, but agreed to redeck it anyhow.

Car should be up and running tomorrow if all goes according to plan

 

So... broke a head bolt, HR head bolts are garbage/defective post-2011 production - full story here:
https://my350z.com/forum/maintenance...l#post10222045

New Juke head bolts coming in overnight Saturday Fedex delivery tomorrow lol. So tired of driving this Chevy Cruiz rental lmao...

 

My head gasket blew recently as well. Interesting to read about your experience and the upgrades you're making, which may end up help me through my process. More info you can post/share the better.

 

If you're doing the leg work yourself, or even if you have a shop do it. Make sure they follow the FSM. I have 1 head measuring 9.970 and another at 9.978, so compression will be ever so minimally different, but the 9.970 one is .005 too thin, so I'm slightly worried about piston-valve contact issues. I think I should be in the clear though, it's barely out of spec. Both would have been fine if I didn't get unlucky having to resurface one of the heads twice... apparently his machine takes off .008 each pass. I don't want to have to source a custom thicker head gasket or worse new heads.

Cylinder head valve guide hole diameter 9.975 - 9.996 (0.3927 - 0.3935) 10.175 - 10.196 (0.4006 - 0.4014)

BTW:... "Posts: 1,337,016,506" what the hell lol?

I'll post results with the Juke head bolts. From Juke FSM, these head bolts procedures are:

a. Apply new engine oil to threads and seating surface of mounting
bolts.
b. Tighten all cylinder head bolts. 40.0 N·m (4.1 kg-m, 30 ft-lb)
c. Turn all cylinder head bolts 100 degrees clockwise (angle tightening).
CAUTION:
Check and confirm the tightening angle by using an angle wrench [SST: KV10112100 (BT8653-A)] (A) or protractor. Never judge by visual inspection without the tool.
d. Completely loosen. 0 N·m (0 kg-m, 0 ft-lb)
CAUTION:
In this step, loosen cylinder head bolts in reverse order that indicated in the figure.
e. Tighten all cylinder head bolts. 40.0 N·m (4.1 kg-m, 30 ft-lb)
f. Turn all cylinder head bolts 95 degrees clockwise (angle tightening).
g. Turn all cylinder head bolts 95 degrees clockwise again (angle tightening).

 

So, car was done today. Turned over and started - more smoke yay. Definitely piston rings, and 1 cylinder had low compression with occasional misfires. Let this be a lesson to all. Don't do things out of order, and tear your Z apart assuming 1 issue (head gasket) when it could in-fact be 1 of any 3 issues (piston rings, head gasket or valve seals). At least my mechanic is saving me lots on labor.

Side note: cams sound nice and with low compression (60) in cylinder 2 it seems to still have more power still than my Z before the failed piston rings/head gasket. We'll never have an honest comparison though since I am now forced to shell out money on pistons, rods, rings

Considering ordering this from Z1 tomorrow:
http://www.z1motorsports.com/350_g35...oducts_id=4266

Need to call JWT and see if they have any good deals on a built short blocks on the shelf somewhere lying around. I would go with IPP's short block, but 4 weeks turn-around time just wont work right now. I could get orders in 2 weeks to PCS and move out of the state.

What's a good price to get a short block assembled locally by a good machine shop? Z1 Motorsports wants ~ $4900 for an assembled short block (minus $1200 after core return)... I feel like I can get a better price on the assembly locally... $2k for labor & shipping to build just a short block seems excessive to me. My mechanic only charged me $600 for the head gasket job, and is going to do the removal, long block assembly AND install for $600 now because he's super cool like that. He's built engines before, and I could have him do it - but don't want to put him in an awkward situation where he's warrantying $4,000 worth of parts and **** for only $1,200 worth of labor.

 

my honest opinion, get a junkyard motor, WAY cheaper and you won't see HP gains from forged internals, plus you could have it in your car in a few days, I am so glad I did all the work myself, the money you are shelling out for this is crazy

 

Already paid for the short block build. I don't have time for doing the leg work to a machine shop and all that at this point. I will be moving out of the state any moment on new orders, just hoping to squeeze this build out before I leave.

Forged internals don't give you HP gains no, but they allow you to rev higher, and JWT C8 cams do need that higher power band. Not only that, but 6600RPM on OEM final drive yields such pathetically short gears. 2nd tops out at 66, 3rd at 88, weak.

 

I hope you know that you wont make power to 7000, it will die at 6600ish again. I had the same cams and better supporting mods than you have and i only saw power to 6800 just to give you an idea. I saw your post on the FI forums, if you are planning for boost in the future, maybe that should have been a part of the plans here, thus why I suggested a junk yard replacement. Don't rush into things just because you are PCS'n I built my block on my old 350z pretty much for the same reasons, ring failure on cylinder 6, trust me, it gets really expensive...

 

Hm, that's somewhat disheartening. I thought these cams would see power to at least 7k. Oh well, I'll be fine with a strong running motor at this point. As far as costs, it's all paid now and yeah, it has been expensive

 

With proper headers maybe a better exhaust (I think bases I is 2 1/4? and a really good tuner (I gained 20hp from a better tuner tuning mine) I don't see why you couldn't get 300hp, what I would keep my eye on if I were you is the progress of the LS TB on a 350z, with a modified upper plenum, expect more.

What is sad is that at the end of the day spending the money you are on your engine on a V8 would make so much more power, kinda the reason I sold the Z

 

Ya, exhaust is something like that:
2 1/4" dia. tube in, with resonators and "X" Crossover, dual 4x8 mufflers, 2 1/2" dia. out, 4" tips ...might trade it for something else if it ends up not working/sounding good with the end-setup. Headers should be okay, these are the same headers 1cockyz used and apparently he lost power when going with the PPE long tube headers. I can't say why, those were just his results apparently.

I think all I really will need is a wider throttle body/intake tube/maf tube. All in good time. I'll be done for a while after this rebuild is dyno tuned.

 

Man, sorry to hear you're running into more problems. That's what I'm afraid of finding on mine since I had 155K miles, not to mention years of racing + nitrous. My Z hasn't even been touched ever since I found out that it's spewing white smoke a few weeks ago.

 

So per both the short-block builder's recommendation and my mechanic I am replacing the timing tensioner, tensioner guides, timing chain, water pump, and oil pump.

I have been doing some additional reading, and know that the rev-up oil pump is a direct fit, and common upgrade to the DE pump. I also read the HR oil pump is the same as a Nismo oil pump, just a later version or something, is that true? However, I have also read the HR water pump is a direct fit, and that it is just under-driven because the expected higher RPM.

Going to get a HR water pump (since it's better suited to higher RPM's, and is cheaper).

Was debating between rev-up oil pump and HR oil pump. Decided on HR oil pump, apparently it's almost the same as that $1,200 Nismo oil pump?

Reference:
http://g35driver.com/forums/engine-d...omparison.html

Edit: If you're reading this, disregard getting an HR oil pump, not a good idea. I went with the rev-up version after talking with JWT some more. HR oil pump gears wont withstand the DE/rev-up crankshaft vibrations. HR crankshafts are better, and don't destroy oil pump gears as easily, so the gear metal is softer than the rev-up oil pump gears. I made a thread about it in the maintenance section.

 

I used a rev up oil pump, as for the water pump, I left it alone, I can honestly not remember anyone saying theirs had problems.

I did not replace any of the timing chain tensioners personally, but it is a good idea being as they are plastic.

 

Rev-up oil pump it is, unless I can get a used customized oil-pump with modified gears for a good price! Reasining here:
https://my350z.com/forum/engine-and-...ter-pumps.html

Also, probably going to replace water pump with one from an 09 Maxima, or later. Apparently the impellers are redesigned, but the drive sprocket is the same size, so there shouldn't be issues with timing.

Edit: Late edition Maxima water pump appeared exactly the same as the early DE water pump. Both cost the same. Maybe the angle of the impellars is different, probably will never know or notice any difference....

 

Was supposed to break in the motor today, but didn't have the clutch alignment tool to get the engine back in . It's happening tomorrow though, for sure!

Engine is built and ready!




I should have the first 100 miles of engine break-in done tomorrow, and will post up a first start vid and breaking-in vid