For the boosted guys....

What kind of headstuds are you running? Please vote and post your choice and why...and how the car is holding up.

 

You forgot 1/2 head studs.

I ran them for 9000 miles @ 525whp, my heads lifted. The community was led to believe it was the way to go for over 600whp 2 years ago.

I rebuilt, and didnt have another set of heads, so I used them again.

Much more power/rpm now, no issues thus far. If I was recommending headstuds now a days, it would be to simply do L19's. No drilling of the heads required.

 

Standard ARPs for me. No issues thus far, only around 2000 miles on it.

 

L19s on my personal Z, street driven at 500+whp.
L19s on our drag car, track tested at 1000+whp and many 8second 1/4mile passes.

There are other varieties such as 14mm studs, but I see more problems out of the big studs than I see good. If you are battling with head lift that much, you need to examine the person doing your deck prep, tuning, and/or tq'ing procedure.

 

L19's....so far so good...

 

L19's here

 

What is your setup, what kind of power are you running?

 

I knew I was forgetting something.

What would you recommend for someone that has ~500whp with the 1/2's? What about the L17 at the same power level?

Thanks berto

 

+1 i agree with berto

 

Basic built block (Arias 8.6CR pistons, eagle rods, HKS headgaskets.. Mostly stock heads, just some P&P, and stock cams), turbonetics ST, UTEC. Currently 380 on a dyno dynamics at 8psi. Waiting on meth injection (and wanted some more miles on her) and then I am going back for a high boost map. I need more boost to make up for the fact that I lowered the static compression ratio with the Arias pistons. Thats something I would not have done in retrospect.

 

Thanks for the info! My vehicle is also running 8.6:1
But I'm closer to 500whp

 

L19 here. I see 16psi of boost everyday...

 

Any build from 400whp-1000+ as we have seen, L19 IMO is the way to go.

I know some are fine on L17, and stock HR studs/etc but L19 is proven time and time again and in other applications. I dont think the 1/2" studs are any worse really but why complicate the build when you dont have to you know...

 

I appreciate the input. Looks like it's time to do some head work, add cams, and upgrade to the L19's for me.

Current mods:
Built shortblock 8.6:1
Arias Pistons
Pauter H Beams rods
Cometic Head Gaskets
Greddy TT kit 2 TD05-18 turbos
Tial External wastegates
SVR technologies wastegate relocation kit with open dumps
Utec with wideband tuner, 3 bar, and map selector switch
Greddy profec B spec 2
Greddy turbo timer
Spec stage 3 clutch and lightened flywheel
Motodyne 5/16 iso thermal intake spacer
AAM oil return lines and pan spacer
AAM fuel return with rails
RC engeneering 750 cc injectors with clips
Walbro pump
HKS SSQ bov

 

Nice build, I didnt know you were FI man.

Ive had 2 sets of cams. JWt S1's and BC stage 3 now.

S1: NASTY midrange, spool slightly faster than now. Made the car leap out on runs, the midrange was so fat. Decent top end pull to 6300rpm's. After 5000rpm's the tq took a dive

BC stage 3: doesnt hit initially like the S1's powerband did, and it makes the car feel much slower (compared to before). Helps in traction. Doesnt make the peak TQ at lower boost like before, but excels at high boost. Decent power to 7000rpm's. TQ curve is much better up top, doesnt fall like it used to.

Good luck!

 

Thanks a lot. The car has a stock revlimiter, and it's an 03....so it's low. I don't think I'll be seeing 7k RPM's anytime soon, 6800 is my max currently IIRC. Of course, a torque dive at 5k rpm's isn't awesome, but how was the HP at that point with the S1's?
What is your revlimiter set at? From your post, it seems you like the BC cams more overall.

 

I don't have a comparison to the S1's, but in your case I would suggest the BC stage 2 (264's) instead of the 272s.

 

Thanks Hal. Any specific reasoning? A blend of the two?

 

I would say 80% of the FI guys on the forums and the racing they do or dont do, that the S1's would be plenty for them. The Hp @ 5000rpm's was awesome with the S1's, and its not like the car was slow, it trapped 126mph letting off briefly with the S1's power curve and 525whp (DJ).

On the recent rebuild I went for more upper rpm power, but man was I dissapointed the first time I went WOT. The car makes more power but it doesnt feel like it, just ask Sharif how upset I was, it felt weak, it had lost its nastiness as soon as you hit it.

The car has been returned since then and Im finally happy. Limiter is 8000rpm's, power is good to 7000rpm's but I have it set for another 1000 for the lower gears and mostly for track use for 1st and 2nd gear, and to stay in 4th down the 1/4, its not for everyday use.

For what it's worth, an almost identical build to mine, and same turbo kit but with BC stage 2's provides almost the same power curves. My car makes slightly more power but that could be from the fresher engine, highert comp, newer turbo's, etc. I was shocked the stage 3 didnt provided more oomph over the stage 2's. For the idle characteristics of the 3's (so, so) they dont seem worth it for most people, maybe even me. But, like I said the retune helped, my car makes 604whp @ 13psi (my lowest boost setting) and it pulls like mad up top, but it doesnt have the initial nastiness it had before. For 7000rpm worth of revving, the S1 would be the better overall choice, I truly loved that power curve.

edit-for what my opinion is worth, 95% of the people on the forums dont need headwork-meaning any port work, valve jobs or polishing. It's not until you start maxing your turbo kit and/or are going for huge numbers with lots of boost that you see the benefit of the headwork. My car on the old setup made 541whp @ 15.5psi on Forged's dyno, jkenefic made 540whp @ 15psi with $5000 Cosworth heads, at "normal" built boost levels its a waste of money. Cams and valvetrain is what I did with no regrets.

 

Excellent, very appreciated info, Berto. Thank you.

Hmmm... valvetrain and cams is much cheaper than what I was thinking about before....guess it's time for an oil cooler and more monitoring devices.

Anyone else with input about their FI headstuds, chime in!