Is it necessary to use JWT valve springs when using the 3.0L JWT cams or are the 3.5L valve springs strong enough?

 

what rpm are you gonna run? If less than 7000rpm, I would not worry. The JWT 3.0 cams are not too much different than the stock 3.5 cams anyway are they?

 

Per this thread: http://forums.maxima.org/showthread.php?t=414267 ....Maxima VQ35 cams have 9.5mm of lift vs. JWT VQ30 cams 10.54mm lift.

However, the Rev-Up model 350Z cams have 10.5mm lift, so I wonder if you could find a set of those springs for cheaper then JWTs.

 

i've been in a 3.5 max revving at 8k, so they should hold up fine.

 

shweet, i'll take a look

 

Just call DAVEB and price them....I have a feeling JWTs might be cheaper though.

 

Alex, do you know what the overlap on the JWT cams are? I called JWT today and Ben said he didn't know what it was. I just want to make %100 sure these are going to be good for my setup

 

What? He doesn't know?

All I know is what they have on their website which is 256-degrees duration and 10.541mm lift. If they gave us intake and exhaust opening/closing we would easily know.

I'd bet you could send them to cam doctors or something to know for sure, but you don't have time.

IMHO, install them. They have the lift increase you want and the 256-duration isn't real aggressive. The VQ35 versions have 260-degrees and they show nice gains. Put it this way....if you don't buy them...send them my way and I'll pay for them.

 

He called me....how's that for service!!!

Good news is that the Rev-Up motor springs are only $95, however you *MIGHT* need shims which would run $50-$60 more, I'm not sure. The problem with JWT including them is that every motors' shim varies, so I don't see how they can offer one size fits all. Also, the non-RevUp springs are 84-95lbs/in vs. the RevUp 110lbs/in..

Bad news is that the retainers are different part numbers on the RevUp and there aren't enough in the US incase you needed to swap those.

Dave is ordering one spring and one retainer to see if the physical dimensions are the same non-Rev vs. Rev. Just need to get StephenMax or someone to get Dave a non-Rev spring/retainer.

 

ha now thats what i'm talking about. I would get the springs and retainers, but i can't wait. We "should" start putting everything back together on Thursday.

 

Speaking of JWT cams, does anyone even have dyno sheets of them on a VIAS or MEVI intake motor ? I really want to put cams into my engine (tensioner is rattling and needs to be repleaced anyways) but I don't trust anyone redrilling the camshafts for proper dowel pin placement unless they use a degree wheel. Thats why I am thinking of the JWT cams, eassy drop in provided I don't have to play the bucket/shim gam to get the right lash.

 

I thought you said you were going with the HKS set coming out that worked in both the VQ30DET and VQ35?

 

Yes I was going to go with HKS or Tomei cams, but the problem is I do not trust someone with 1200 dollar cams drilling them out for me. I reather just drop the cams in and call it a day reather than send cams out and then have issues with it runing or making any significant power gains.

Alex do you know of any DE-K or even MEVI motors with JWT cams ? If they gain bout 20ish WHP on top end and don't sacrifice low end I will buy them. I need to do timing chain guides and tensioners on my VQ anyways soon so camshafts would only require removal of the IM which would only add a lil bit more time to the whole job. I have 150K of HARD miles on my car BTW.

 

In an old post you said the HKS had another hole for the VQ30DET dowl, so drilling wasn't necessary IIRC. Anyways, anything with HKS on it...I can't afford. Just wondering what happened, since I haven't seen them ever released in the US at least.

I've only seen one dyno with the JWT VQ30 cams and the was IronLung which I believe had a MEVI at the time:

http://forums.maxima.org/showthread....t=JWT+cam+dyno

 

Alex,
HKS Japan doesn't have any of those cams avalible at this moment and they dont know when they will have them avalible.

Thanks for the dyno sheet, I'm guessing that it has a USIM as power uptop is getting really flat. Most DE-Ks sing uptop, where this motor has a linear powerband with no surges anywhere- other than the weird spike at about 6100RPM, it looks like power starts to level off around 6K which is un-VIAS like.

 

buy my JWT valve springs. They are NIB sitting on my coffee table.

 

It had a MEVI that opened late, that is what the surge is. The car had cattman headers too. The JWT 3.0 cams are not very impressive. I graphed his dyno on mine and I was not impressed.

 

Do they come with retainers and keepers ? I'm semi- interested- but still awaiting my income tax refund to buy cams and possibly springs also. Got any DE-K heads laying around :P ? Might as well do head work if I am going to be messn around with doing springs. I need to make a few calls bout getting some good head porting done... but I doubt I could afford having my heads done by Dan Paramore Racing.

 

If you are replying to me then yes they come with retainers etc. I however dont have any de-k heads laying around but I do have some DE heads.

 

Yeah after reading more bout it it also said he was having trouble keeping the MEVI open as his surge tank was fubbar or something like that. Regardless of which the #s don't look very impressive, I guess I have to get mine and see. If I can't make 240+WHP I won't even bother posting a dyno. Give me bout 2-3 weeks and I will have my JWT cams. But they wont be in for atleast a month, I need to have my Q45 all dialed in, tunned to perfection before I can put my daily driver Max out of comission for a few days.

 

I just wish people would do before/after dynos with something as critical as cams.

Honestly, I think the JWT cams aren't that great, but then again who knows with one or two after only dynos with JWT or stock timing.

Tomei's would be my choice just from impressions on others, but no dynos.

 

Do you think cams would allow my horsepower curve to not flatten out from 6000->redline?

 

So alex would the nismo cams be a better option for my setup? 262 degree duration w/ 10.8mm lift.

 

I mic'ed two full sets of valve springs for Mardi. One VQ30DE set and one VQ35DE set. They were essentually identicle and the weakest to strongest spring only had a difference of about 6lbs at high lift (2k2 ESM Spec).





Taken from the '06 G35 ESM;

Valve Spring

Items M/T models____________________________________________ _________ A/T models
Free height 45.43 mm (1.7886 in)________________________________________ 47.07 mm (1.8531 in)
Installation height 37.00 mm (1.4567 in)___________________________________ 37.00 mm (1.4567 in)
Installation load 166 - 188 N (16.9 - 19.2 kg, 37 - 42 lb)_____________________ 166 - 188 N (16.9 - 19.2 kg, 37 - 42 lb)
Height during valve open 26.8 mm (1.0551 in)_______________________________ 27.2 mm (1.0709 in)
Load with valve open 434 - 490 N (44.3 - 50.0 kg, 97.6 - 110.2 lb)_____________ 373 - 421 N (38.0 - 42.9 kg, 84 - 95 lb)
squareness 2.0 mm(0.079 in)_____________________________________________ 2.1 mm (0.083 in)



The M/T Models have the rev-up (298hp-7000rev) engine and the A/T models have the older engine (280hp 6600rev)


edit: I just noticed that it lists the same installed height for both springs @ 37mm. Which really means they're direct drop ins and shims aren't to be used. You wouldn't want to shim the springs anyway with high lift cams, because they pretty much max out at 11mm of lift.

 

I have a set of those also, but they are spoken for.

 

SR20DEN,

I'm not sure what you're saying, so put it in layman terms please.

If I understand correctly, the rev-up springs are stiffer and you're saying not to use the JWT included shims?

 

The problem with cams is that while they increase top-end, most of the time they also shift the powerband to the right, ie higher RPMs. Therefore, you might need a raised rev-limiter to see the benefits.

Without more information/dynos, I don't know. However, with your mods and an EU, I'd say the cams are the next mod.

 

What does JWT include shims for? Their own spring sets or their cam sets?

I personally would avoid using shims if you've already upgraded the springs. And at 10.5mm of lift there isn't much left you can shim before the spring starts to bind. I would however revise that statement if I had parts to test so I could personally see that everything specs out without binding the coils.

 

Springs......"Includes 24 springs and shims for use with JWT race cams or JWT street cams with rev. limit raised above 7000 rpm. The included shims replace the stock base shims to obtain the correct installed height (36MM). 43lb@on seat & 136lb@12.5MM lift with coil bi"

http://www.jimwolftechnology.com/cus...asp?PartID=448


JWT VQ35 cams say .428"/10.9mm of lift.

I guess I don't understand how the shims/buckets work on a VQ30/VQ35.

 

Did you end up running the cam on the VQ30 and what was the result?