Opinion on GT-t boost, Formaz

[ARGH34]

I'm about to book my car in at Formaz to up the boost a bit on my R34 (which is currently running the stock 0.55 bar). I've dealt with Kevin from Formaz for a minor service before and he seems alright.

Just a question: what's most boost I can safely and reliably run on a stock GT-t turbo/stock intercooler. Only mods so far engine-wise are cat-back exhaust and Apexi pod filter.

The numbers I've gathered from the forum are 10-12psi (0.7-0.8bar) without running the chance of blowing the turbo.

Kev said he has seen many Skylines running 1bar safely on a stock turbo/IC without any problems. Does this sound right? Keeping in mind I don't plan to do any trackwork or drag runs and that summer is coming up.

Also he plans to use a simple bleed valve + boost cut defender to boost it up. I've read here that they don't hold boost properly and cause spiking. I realise an EBC of some sort is the best option, but will this do? Must I have the boost-cut defender as well? Any comments?

Also, any general comments and experiences good (please share) or bad (PM me) with Formaz would be appreciated.

Cheers.

[rob77]

1 bar is far too much to run on the stock turbo and cooler. The ceramic exhaust wheel will spin off and the car will probably detonate at that boost level with only the stock i/c. Play it safe keep it around 12psi tops, how are they planning on upping the boost? If its a bleed valve make sure you install a good boost gauge at the same time so you can make sure its not spiking too high. If you plan to use an electronic boost controller some of them, like the blitz dual sbc, act as a boost gauge as well.

[ARGH34]

Boost plans to be increased with a Turbosmart bleed valve + Turbosmart boost cut defender.

Yep, the previous owner thankfully installed an Apexi EL boost gauge (together with with a ricey externally venting BOV, which I refuse to spend money replacing).

[rob77]

Thats fine, just make sure it isnt set higher than 12psi or it will blow the exhaust wheel off, and then you'll have to buy a big bastard aftermarket turbo like me although I didnt kill my stock turbo, sold it to a mate

[Hicks]

Nah, the turbo on gt-t's are much stronger than the ones on ours rob. I'm pretty sure they can easily run more boost than that.

[skyzerr33]

the R34 have a plastic wheel which is just as weak as the ceramic one on the R33, it provides faster spoolup but will die just as easily keep at 12psi if u want it to be reliable.

that said i've seen plenty of cars run 14psi all day everyday on the stock turbo and coola with no problems.

[Hicks]

Oh yeah,

Its the internals that are stronger.

My bad.

[rob77]

ey? the internals on the r34 are stronger than on the r33? hmmm.

[Hicks]

I have been told by reliable sources.

[rob77]

Still for what I want, 370hp, the engine should hold up fine. I've checked my injectors to make sure my fuel system doesnt melt me a piston

[Hicks]

What did it cost to get the injectors checked?

[rob77]

cleaned and tested $150. Plus whatever steve @ sst charges me for getting them in and out.

[Hicks]

May be worth doing.

[rep003]

ARGH34, just a thought , when u get the boost set , check to see that more boost = more power. Recently had mine tuned (boost spikes to 13.3psi then settles to 12psi) & discovered when we screwed more boost into it that the power dropped off! (Maybe knock sensor picked up some pinging & took out timing to compensate?) .Having said that , I would have happily run 1 Bar (14.7psi) if it went harder

[Hicks]

Bit of tention in here...

[adam 32]

gone

[GTS-t VSPEC]

I wouldn't bother running anymore than 10psi. The stock cooler in the R34 is better, but still will have 2-3psi pressure drop, but increasing boost any further will add excessive fuel, and you'll find power going down due to overfuelling.

The R34 GT-t's internals are better, the compressor wheel is nylon(plastic) but the exhaust wheel is still ceramic, and won't cope with over-boosting too well.

I'm sure even with 10psi you'll make good power.

[ARGH34]

Yep points noted. Thanks for the tips.

He said he'll take it for a whirl on the dyno when he boosts it up. I guess if nominal power gains are made with 12psi over 10psi, I'll just set it to 10. I suppose next time I wanna boost it I'll need an FMIC and AFC to make it worthwhile?

I was also thinking of getting a full exhaust done at the same time. What kind of a down pipe / front pipe should I be looking for? Branded or get one fabricated? How much are we looking at?

I noticed rob77 said $300-$350 for the pipes in the 'best mods for $5000' thread. This what I should be expecting?

Oh and any comments on Formaz?

[GTS-t VSPEC]

I'd get the full exhaust done first. You may be surprised, but more than likely by doing the exhaust the boost may well increase to about 10psi by itself:D

Yeah, if your planning further mods then an SAFC and FMIC are on the cards:D

I'll PM you my thoughts on Formaz.

[R34]

Yep no more than 10psi.

R34's also may require two boost cut defenders from memory as there are two places it gets its input from.

R34's are a lot trickier than 33's to boost up.