sentry65

iTrader: (11)

https://my350z.com/forum/showthread....ight=wastegate



ok so which wastegate is it?

http://www.turbosmart.com.au/index.php?s=wastegates

looks like the first one

zachcrosen

iTrader: (23)

I have seen that thread before!

Just looking at WG on Hopupracing's website, I see a TiAL 38mm WG that is good for around 350 HP. Does that number mean much for a SC'd system? In other words, would 370RWHP be bad with something like this? On the picture of the TiAL WG, there is 2 fittings on it. Where do each of these run to?

He!l, for this cost, I may have to consider this again but I have to learn more about it first. BTW, isnt the Vortech piping aluminum?

sentry65

iTrader: (11)

just some thoughts I'm considering

the intercooler piping is aluminum and isn't going to be friendly to weld the wastegate onto, but it obviously can be done.

I have a 36mm koyo radiator and there isn't as much room between the radiator and the intercooler pipe where gspot35 has his wastegate mounted. That means on my car it'd have to be mounted somewhere by where the windshield washer fluid is - and I'm assuming there's room somewhere, but who knows for sure. I want to get an oil cooler and that's going to go somewhere in that area too.

Another thing is say you weld in a wastegate and get it all working. By the time it's all done, you've probably spent $500-600, maybe even 700 in parts and labor to get it all up and running. Some day when you go to rebuild your engine block you're not going to want the wastegate because the engine simply can just handle the added power - hell maybe the stock block can even handle 480whp on a vortech setup for awhile.

Point being that someday when you build up the engine - if you were to, you'd want to spend money getting the wastegate removed and patching up the intercooler pipe.

I might just wait for the sake of keeping things simple. I'm thinking that in a couple years when I'm not as broke (just recently gone FI) I'll build up the shortblock with the bored out 3.8 liter darton sleeves and go with the 2.87 pulley

importofamerica

I spoke with the guy that originally built the setup yesterday super nice guy and was real helpful with the info. i will share what i learned and how simple and cheap this would be to do. read the following link. http://hksusa.com/products/more.asp?id=761 this uses the same mounting flange as the vortech BOV and since it mounts in the stock location vortech put it at then there is no issue with room. next it is not as exspensive as a wastegate as there is not need to pay to install as its just 2 screws. simple to install and use and after talking with hks there is no reason to think this would not work on the 350z supercharger as they use these as safety valves on the skylines in japan. i was worried that it would not be enough of a purge on the intake piping to keep from overboosting but hks assured me that they can keep control of 800 HP cars, so i have to hope it will. i am going to do it myself in a month as after chatting with the guy who done this setup with the wastegate i am sure i want to try it. so many advantages!!!!!

zachcrosen

iTrader: (23)

So, what I am reading into this is that you would replace the stock Vortech Bypass valve with the HKS Racing Bypass valve. You would purchase it with whatever MAX boost pressure spring you are wanting; 8 psi spring as gspot35 used with his WG setup or 9-10 psi as I may want to run. And then, in theory, it would bleed off boost beyond the spring pressure and function similar to a WG? And the install would not cost anything as all you would have to do is unbolt the stock Bypass Valve and bolt this one back in place and rehook up the vac hoses. Where would you hook the one hose up that needs to see only boost and no vac? Keep us updated on this and if it works. Just as an FYI, you can get this bypass valve from SP Engineering for around $215 + shipping. So that makes this option even cheaper, if it will work.

importofamerica

i believe it will work as good as the wastegate idea as i talked with HKS and tried to talk to Vortech but they not really seem to interrested in a 350z or anything else pertaining to an import in general, but thats just my impression of who i was dealing with although i must say i have been around domestics all my life and my father swears by vortech so i know there good stuff i just dont think they care about the import crowd as much as the domestics they built there company on. As far as easy yeah it should just bolt to the stock BOV location no problem and as far as a boost signal i am going to come off the intake plenum with that with a check valve in line with about a -4 size line i may even drill and tap it myself as i want to try to obtain the best signal going to it as possible to try to keep boost control as perfect as possible. I am like you i want about 9-10 pounds with more down low as that where a street car stays 90% of the time and i like the idea of the added torque low where i need it.

sentry65

iTrader: (11)

wow this sounds pretty cool. I'm assuming this would change the sound of the vortech BOV though - would it become quieter you think?

zachcrosen

iTrader: (23)

Will you be using the check valve to prevent the bypass valve from seeing vacuum? As I said earlier, definitely keep me up to date on what you are doing.

sentry65

iTrader: (11)

so just to confirm, you replace the vortech BOV with the HKS bypass valve (part # 17670-004100) and that's all you have to do really other than making sure you use the right PSI spring?

what PSI springs does that bypass valve come with? Or do you have to buy springs seperately or something?

who's car specifically is using this setup with the HKS valve? It works with no issues?

booger

iTrader: (6)

I had thought you stayed with the elec. boost controler .

I would think you would still want to vent boost when at idle and light throttle . To keep a better daily drivability . Replacing the bypass valve for normal BOV would keep it closed untill a set boost preasure is reached .
Unless Im missing some thing here .

And having it before the IC , you have to set it at a higher psi to maintain [ say ] 9psi at the plenum . The PSI between the IC and the blower will be much higher than at the plenum . And having it before the IC would seem to be the logical place to put it . So you dont have to cool the over psi . Your only cooling the psi needed to keep the 9psi in the plenum

jakesford

you will still have to have bypass valve along with the wastegate, waste gate will be closed as long as the boost amount is within its set range, so you would need the bypass for when you close the throttle. Wastegates never see vacuum only boost and usually get the boost signal from a fitting directly of the compressor housing. bypass/BOV see both and signal is from the manifold.

The problem i see happening is you could potentially have a difficult time getting smooth boost, and you may end up with a sinusoidal boost reading as the wastesgate releases excess psi. Also the blower will be sapping more power from the engine and there will be more heat in the intake charge...

booger

iTrader: (6)

Your right...and thats how Gspot35 did it . And thats why you want the waistgate before the IC . So you dont have to cool the over boost . And the psi the waistgate is set to open at , will be higher than the psi you desire at the plenum . The trick [ and Gspot35 seemed to get it right ] is not to bleed off to much boost at the initial opening of the WG .

zachcrosen

iTrader: (23)

Booger, what is your thoughts on going with the HKS Bypass valve? Didn't I read the info on it correct in that it will also act like a WG? So, for $225 you slap that on instead of the stock bypass valve, change to the 2.87 pulley and retune and you are set. You would then have boost earlier and still the comfort of not harming the internals by bleeding off beyond say 9 or 10 psi. Am I understanding this correctly or am I completely off in left field?

booger

iTrader: (6)

If the HKS bypass can act as both , and not bleed off to much boost when it opens . It would be worth a try . When some one gets it done and working , I'll use it and have it open at 13psi . My boost now , from 6000rpm to redline jumps up and down each time the belts slips from 13 to 13.9psi at the highest . ANd most the time , 13 to 13.7psi

importofamerica

Booger is absolutly correct you for sure want to put it in the stock location of the vortech BOV as you do not want to run the extra boost thru the I/C so you can keep the temps down as yes i believe you will be making more heat with the 2.87. According to my friends in japan i talked to saturday night they told me the same thing as HKS USA said as far as the BOV wastegate trick should work with no problems as thats what it was designed for and there info came from a friend we met while i was stationed there that worked at a company called top secret. these guys know there **** when it comes to skylines. The spring that comes with the wastegate will not work for us, it has to be the yellow spring and i think its like 25.00 extra. Booger i understand what you are saying about the signal hose going to the intake, if it was you where do you think the best place to put this is as i want to do it this week while installing the supercharger. i want to tap this in and put a A/N fitting in while its easy to get to. I think if i get into a boost control issue, i will use the profec b spec 2 i have been holding onto. i really am a firm believer in simplicity, and if i can make it work with the spring along i will but thinking about it more thats one of the advantages of a good boost controller is that you keep the boost source closed to the last minute until the exact boost pressure is reached then it opens all of a sudden keeping you from bleeding boost and getting better control of wastgate management. you can also adjust it if your getting boost spikes as to bleed off earlier to keep from getting a spike. maybe it will be best to use it as i can have a degree of control over it. also this would be cool i can use the gear dependent settings to control boost in certain gears like i did in my other car to keep from blowing first and second away when the boost came in. also you can use the fuzzy logic to learn your boost curve to help predict and control boost. Again this is all still in the working state but it is just an improved idea that Gspot35 proved could work so maybe if this works out well you will start to see HP and TQ numbers closer to single turbo kits with more torque in our powerband where we can use it to our advantage. after looking at timeslips i am now glad i got my supercharger as the times are as good as the ST systems as we can hook up and if the torque improves we will see the trap speed increase. yeah

gspot35

I think when booger was researching the HKS, he found it would not allow air to vent when the engine was not under load.

Import, I'm not sure if you realize this but the blower is constantly pushing air into the atmosphere except when you are putting load on the engine, it closes and shoves it into the rest of the system, ic, tb, im. I know you know your stuff but I just want to make sure you're asking the right questions to HKS and your friends. I don't know why a turbo system using the HKS would function this way. It should not need to vent air as the turbo is not a direct couple to the engine/rpm like a s/c setup is.

Also the guy who mentioned the vortech plumbing is aluminum, good call. I had to get a steel pipe welded. I was lucky to have so much room. The guy who has my kit now has the wastegate on one of the 180 degree pipes in the fenderwell. It's completely stealth. The only issue with his is that it's after the intercooler instead of before. Please keep this thread going as you are conquering your challenges.

sentry65

iTrader: (11)

i'm guessing the downsides to not venting the air is you'd have to run more fuel and get worse gas mileage, though maybe slightly more throttle response?

yeah sounds like a setback. I hope something simple like the HKS bypass valve works, but I have this feeling we'd need a true wastegate like what gspot35 runs. And putting it after the intercooler just sucks. I guess if you have water injection it might not matter as much, but it's just such a shame if a wastegate can't be put in before the intercooler - like if you have an aftermarket radiator.

I hope someone figures something out, otherwise I'm not touching the 2.87 pulley until I get a built engine and water injection

zachcrosen

iTrader: (23)

Why cant someone just fabricate their own WG flage and weld it to the aluminum piping before the IC? It does not seem like it would be too tough. Seems like you would just have to drill a hole in the aluminim piping, then weld a tube to it a a 45 or 90 deg angle and the weld a mounting surface to the tube. Just doesn't seem to tough to be able to fabricate to me.

booger

iTrader: (6)

Think you got me mixed up with the guy wanting to try this . I have never researched HKS bypass valve

zachcrosen

iTrader: (23)

I just bought a TiAL 38mm WG with the 8.7psi spring in it for $210 and it included the mounting flange. I will probably have a guy locally use the steel flange included to fabricate an aluminum one and then have him weld it to my aluminum piping. I probably will not actually do the weld work or anything else for a while as I am strapped due to the ZDayZ thing coming up. I will probably do this in a few months. I plan on going to CP Racing and have them install the 2.87 pulley and belts and then retune for me.

I will keep everyone informed of the progress as I work on this.