Just ordered a set of Tomei 268deg cams..

and I am just wondering what the stock valve springs can handle.

I am currently using stock ecu, but after an ecu tune, i am hoping to run 7000rpm (non rev-up), 400rpm up from stock 6600rpm.

has anyone got similar setup here? anybody running tomei 268's with stock valve springs and raised the rev limit?

 

Considering that 268 cams are very mild and 7000 rpm isnt very high in the band, I would be disappointed if our stock valve springs couldnt handle the them. But this is only my opinion.

 

you can read my mind.. that is the exact hope i got right now

it will be easier to do it at once than pulling the engine apart later again just for the springs.. but then again i wonder if it is actually needed or not.. as i will be just spitting my $$ out the window if its not required.

and also hoping to see some feedback from someone who is actually running the same setup out there.. come on..! there must be a fair bit of people out there!!

 

Tomei 268's are not very mild at all...they are pretty aggressive on the 350Z platform. With the amount of lift on those camshafts, I would definately suggest at least using a set of JWT spring/'shim kits. They are cheap, and well worth the money.

 

I agree. I mean, you're doing a pretty big enough job by installing cams you might as well do some other valvetrain parts at the same time.

 

Sorry for my ignorance. We used to run cams in the 300+ deg range in the honda motors, but i spun those motors to 10k. 268 seems very mild to me but i guess not on a low rev'ing v6 platform.

 

how easy/hard is it to replace the springs? its not gonna look pretty if the valve drops into the cylinder as soon as i took the retainer off ! any tips?

 

Mild? They are among the more aggressive cams offered for the car actually, especially given their ramp angles. Remember, there is alot more to a cam than just the lift and duration

These cams need aftermarket valvesprings.

 

Well compared to their 272 and 280 degree cousins they're mild considering you can get them with 11.3mm/11mm lift.

 

See post #6

 

I am running custom 265 / 11mm lift cams (intake and exhaust) to 7200 and doug is running 290 /11mm Intake and 265 / 11mm Exhaust to 7200 on stock valve springs. We each have about 35K miles on the setups. No issues here. I recall the tomei's needing the springs tho, as adam has said above, there are more to it than duration and lift.

 

Adam is correct, Tomei's website recommends their upgraded valve springs for any camshaft above 264 degrees.

I recommend installing a set of strengthened (ARP or Nismo) connecting rod bolts so that you will be able to bump your redline up to 7200 rpm and get a little better powerband from those camshafts.

 

how often do you/doug hit the 7200rpm? do you goto track days much?

the latest tomei broucher says the springs are needed if the lift is above 11mm, and their 268deg cams are only 10.5mm lift..

 

I went ahead and put in nismo springs when I did the tomei 268's

works like a champ

 

Tells us more about your setup. I am really interested if you are n/a or f/i, did you port the heads along with your cams, how much power did you gain with the Tomei, and if you are tune what kind of tuning mod did you go with? Oh and what year is your Z? Thanks in advance.

 

My Z is a 2003 Track, the forged engine was put in by CPR (shop Sharif used to be associated with in Charlotte prior to Forged Performance) with parts bought through Forged Internals.

Parts list was:
Brand new short block, bored .030 over with Arias 8.5 (or 8.6, can't remember) pistons and Pauter rods (beefy *****). Opened up the heads quite a bit (from what I hear) and put in the nismo springs and tomei 268's. I don't know exactly what was done, and didn't get before/after flow #'s, but the car definitely sounds and pulls like a beast

It's N/A for right now, but as you can see from the CR on the pistons, i've got alternate plans. I'm at work right now (as you can see from my location), but once i get back to the house I'll be getting an APS extreme and making that engine work for it's chow, hah!

Total list of mods right now are the above engine mods, pop charger, angled plenum spacer, test pipes (with a gaping hole on the drivers side since i blew off a O2 sensor during a high-speed run on the autobahn), nismo exhaust, lightened pullies, ATS carbon (light weight / medium grip) clutch/flywheel package, Cusco RS 1.5 (60% lockup) w/ nismo cooler, 350evo sways, upgraded pads, lines, tires... probably fogotten stuff too, lol.

This pulls pretty well once you get about about 2500rpm, drops off a little bit after 6800 or so, but it goes by so fast the only time I notice it is when i'm trying a top speed run. It's still N/A so i don't have any illusions, but once i get those turbos all set up and tuned i'll go find that modded C6 ZO6 that I ran into the other day and try again, lol!

 

nice setup, so the engine is turbo ready, slap in the turbo and thats complete but you must be losing quite a bit of power for staying NA with 8.5cr..

 

Machupo from what you tell me it sound impressive. So the Z still pulls hard with a low compression and cams amazing. I was also wondering if you did a port and polish to your head to go with your cams? Thanks for taking the time to tell me your specs.

 

yeah, probably losing 15-20hp because of the CR, but it'll be worth it with the big turbos



CPR also did a port match and polish while they were in there

 

Glad to hear things are going well so far. When is that thing going to be FI!! I too, was surprised with the power your engine made NA, even with 8.5:1 CR