T28 w external wastegate?

[WhiteGLX]

I am planning on weldingmy flapper wastegate shut on my S15 turbo and modifying my tubluar manifold to hold an external wastegate right where all 4 tubes come togeather before the flange. I am doing this because i have come to the understanding that the external wastegates tend to keep better boost numbers, no boost spiking basically, as opposed to teh flapper style on all our factory style turbos. I can either rerout the waste gate gas back into my turbo extension, or instead of modifying that at all, just run it out the bottom of teh car. All opinions on my ideas are welcome, and constructive criticism is needed, i have recources to do all this, and haveit stuck in my head that it will help int ehlong run.

I am doing all this woprk because i plan on being involved in many rodaraceing opportunites(5.5kish rpm for 20min strait basically), no drift or drag.

[wootwoot]

what would be easier is a good electronic boost controller

[silviasichigo]

another option is a (Gater) for thoes of you who do not know what it is it...........A hole is cut infront of your flapper on your outlet pipe and a 1"-1 1/2" tube is welded to that hole and well the you have to cut the legnth of that pipe to the size that you want for the sound that you want when the flapper opens up, i has a few uses if you just like the cool wastegated sound then there you go, it also allows debris (carbon, metal chunks what ever to blow out) you would think this would sound just like and exhaust leak but that is not the case sounds great actually. Oh and by the way the gater will let you know when the acuator opens you will hear it automatically because the sound will increase dramatically. So if you are hearing the sound increase but the guage is still reading vacuum then you might have problems. but This is just an option with out having to risk jacking up your manifold. you can order these gaters through Night Pager they are in japan but the distribute

[WhiteGLX]

i thought about the electric boost controller, and asked around to soem guys that road race turbo cars, tehy all said its just the flapperstlye gate that seems to be all over teh place, teh external ones hold a steady boost better, more reliable. Im not worried about jacking up the manifodl, mine already looks.liek ass from previous issues with the engine, not shiny or pretty anymore, just doin what its supposed to do. Its not the noise of the wastegate im looking for, just a more reliable and stronger worry free track car.

[msaskin]

I never had boost control issues w/ my stock turbo and an EBC, but then again, that was stock turbo.

The main benefit to an external gate with a larger turbo is that it will allow you to keep a smaller sized o2 housing. I'm running a Tial 38mm external gate with my GT25R on a stock manifold. Let me know and I'll take some pictures of the setup.

~matt

[wootwoot]

^^^^you better post pics, im curious

[WhiteGLX]

yes...pics will be nice

[silviasichigo]

Yeah good point but I have had problems with a few eletronic boost controllers actually all three of the major brands Apex AVC-R the BLITZ SBC and the PROFEC B I now have the PROFEC A which is the stepping motor type boost controller. I boost everday driving 1.2 but when I drag or play around 1.5 with the APEX I it would spike severly (I was still acuated then) so I thought it was actuator bleed but then swapped out the actuator and same problem the solonoid (SP?) would overheat even right beside the air filter where I had air rammed right into the engine bay. same thing with the SBC over heat or just straight up malfunction they were all new and the were all installed correctly the profec B just did not have the umpfh I needed to keep a steady boost curve so I finally settled withthe PROFEC A and had it ever since So a PROFEC A will steadily boost your car on a solid boost curve with precision so if you settle with EBC then PRFEC A or the new HKS EVC is also a good one very solid boost curves.

[WhiteGLX]

i just installed a Hallman Manual Boost controller today and a Autometer boostgauge, the controller is still set for stock 7-8psi, im not goign to turn up the boost itself until this weekend when i get the car dyno tuned with my SAFC-II, i think im goin to run like 13psi, since im only on stock injectors. But you have just proved what i have heard about the electronic boost controllers malfuncioning or just not working as well as most people say thay can, i ca actually save money by goin to an external wastegate instead of goin with HKS actuator and EBC, so from my point of view it seems like more of a deal to put more effort in.

[silviasichigo]

well glad I could help. I am externally wastegated too and with an EBC I have never spiked. Knock on wood!

[WhiteGLX]

well the externally gated part has to be part of it with your setup, so thats the attitude im goin for even tho when all is said and done with this upcommng project, ill only be running like 16psi. Its just the fact that i dont wanna think about the car breakin, i wanna be worry free, so stronger is better in this case.

[tastyratz]

external gating is great for reliability and better boost control and can actually build power if you outflow your turboback and route the wastegate out somewhere else. dont merge it back into the exhaust because you want the most laminar undisrupted flow...

[WhiteGLX]

these are thing i just needed to hear from another person, its still a a debate wheater its an upgrade from the factory S15 setup, thats what i really need to know

[tastyratz]

ask sohcturbo. he just boosted his sohc with a t3/t4 and runs external gate. he swears all his high end is from the external. the other thing about external is you dont have to worry about running a tighter a/r on the exhaust side killing your top end. alot of people run a larger a/r since you get more top end at expense of lag but turbine flow is not as much of a concern with ext. wg. so you can just run it very tight :)

[WhiteGLX]

well im not switchin turbos, im just modifying my already internally gated S15 to use and exterally gated system. I was hoping to get input form someone on these forums who has done this project.

If you know anyone who has done this, or knows it will be beneficial for what i am going to be doing let me know, still tho...thanx everyone, helped even still