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dont think so, its the first thing i said to the tuner, but with the gate on, it got up to around .9 bar, started to flatten off then started creeping up again, indicating it should have the right spring in there. also note those boost figures were generated at like 5k, tuner backed off when he saw it keep climbing. the gate may be on the smaller side, but its obviously not the main issue here, i mean 13psiw ith no gate at all and still climbing rather rapidly. we shall find out soon anyway, hopefully we'll know results in the next few days/week

Without going on about this all night, being 1am, I'll start by saying that I wish people with little to no experience would save their comments for things they actually do know what they are talking about.

So first item on the agenda. I have built at LEAST 400-500 RB nissan manifolds to suit GT35 turbos. The manifold is essentially identicle bar the head plate and port spacing between RB30, 20, 25 and 26. I do the same gate outlet on every single one, and a large % of my customers use Tial 44mm gates. Of the...... lets say 300 manifolds I've done, maybe 10-20 have had boost control problems. Now who would like to tell me why less than 5% of people have a problem if its solely the manifold to blame??

Its not. Simply, when you run a big efficient engine, with a turbo that is easy to spin, a manifold that has no reversion, turbulence, and perfect design/scavenging, its going to get VERY difficult to keep boost levels down. The biggest culperets are big exhausts with no cats and 1 muffler, offereing no resistance to turbine flow, usually small to med cams, and people who don't want to listen. Why will a 60mm gate fix the problem if the manifold still boosts to 13psi with no gate?? Because the surface area of the exit is 70% greater for a start. Also, if the boost changes 7-10 psi with the gate on, its obviously a restriction yes??

I have tested and found the 60mm gate to work, I offered this as a solution, not a suggestion. I offered to trade the used 44mm gate in on a new 60mm and modify the manifold to suit for free, total change over being $400 which is the cost difference between the gates new, but Andrew chose to have a go at fixing it by themself. I have no problem with this, however its a case for me of everybody not understanding that no one part can be made to work in every application every single time. I have cars with almost identicle setups and no boost control issues, Mercury Motorsports RB26/30 drift car being 1 example. Its simply a matter of working thru the issues for a usable result, rather than looking for someone to blame.

I have however found that the Tial gate has limited valve travel with both springs installed(1bar is inner and outer spring) and I suggested to remove the outer spring and give it a run. In my experience, it has brought the boost down by 5-7psi, and the graph I have been given for the above setup shows about 3psi per 1000rpm, and stops at 20psi, I would expect a top of 25-26psi by redline, and with the spring dropped out, boost to come down to around 20psi. I was told this was tried, but given no dyno graph to show it at this point in time.

All I can say to people is don't ask for advise if your not interested in listening, my experience is hard learned and earnt, extensive, and 9 times out of 10 more accurate than the mates and people around you offering "advise". You can't always please everyone and its really disheartening when people just look for the easiest person to blame rather than understand that sometimes specific setups just require more work to get right. All the best with the gate mods andrew, be sure to let me know how you go when its back together and how the boost control works.

Regards..........................Kyle

6boost.com

0410730598

well results are in.

modified the manifold for dual ports, cut the wastegate port off, and running with no gate. still overboosting. but it taps off at around 10psi and slows down to 13psi. which is alot better then before.

f*kn dont know wat to do anymore

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  • Latest Posts

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