I also found that wrong / bad placement of the wg's can cause preferential flow through the turbine instead of the gate/s , if it (the turbine ) is of an efficient design and is large enough in size , and we all know how much we like large turbines . Please post what happens when you put it together , I may be interested in getting one myself.

true divided is one of the reasons for dual wastegate but it is no where close to 76mm like you mentioned, more like 54mm worth...

i think i should be fine about boost creeps. i actually have a picture of a manifold from BLITZ's drag car and they welded the wg at the same spot as mine and they are running some crazy boost. so i got the idea and told him how i wanted it and we fab up the manifold. it was a bitch fabing this thing together because 1. we have to worry about equal length 2. clearence for the two wastegates 3. clarence of the dp 4. eazy acceses to the manifold nuts and etc..... anyways, i really like how it turned out and i should have my car running by Friday still have alot of shit that i need to put back together. will keep you guys update about the boost creep issue.

do you have a picture of your set up? gotta love the look of those dual WG'S manifold. :)


steve

Looks like another masterpiece by Sean. I'm glad that all of you guys keep posting the work he does for you. It makes my decision to go to A-spec all that much easier. Now I just have to get back to the U.S. so I can start building my car. :)

Back on topic, GREAT looking manifold. Please do let us all know how you like it once it's put together.

Zach

Ahh, straight for 4.25" before the bends. I think mine is straight for 2.5" and where the old WG runners came off the mains was ~3" from port. I think that is why I coulden't control boost, too close to port. It looks like your manifold places the WG runners ~8" from the ports? You should have much more luck than I did.
Again, Nice manifold and a damn fine job welding it also :)

Who'd have thought a manifold could be sexy!!

Damn nice work there!

Excellent manifold fab work.

~Mike..........

6 to one, half dozen to the other, when you buy or sell your wastegates on your kits do you go by surface area or by what they are sold as? not that I agree with the later. But you do sell them as twin 38mm gates no? Not 54mm worth of flow.

But since you brought it up you are correct about 54mm of surface area, but valve to diaphram area will be greater than said 54mm gate, allowing for better control. As usual your posts are always informative but never complimentary.



Thank you Zach, let me know when you are ready to go!!!



The other thing I always try to do is run the wastegates off the bends, and split the difference, air would prefer to go straight and does this way, if you just slap the gate on the side of a pipe it will require higher manifold pressure to force air through the new opening the valve created, Higher pressures and more heat are not a good thing.

Thanks for all the compliments. They mean even more coming from someone who builds one himself. I'm not saying all you guys dont matter, just that a builder knows/appreciates more about what amount of work has gone into it.


-Sean

Very nice work. I don’t even want to try to guess how much time you have in it especially if the pipes are within a couple of mm as you stated. As for the people who say the wastegates will not work, Bull – they are positioned the way they should be. I seriously doubt you will have boost control issues. Nice work

Have you got pics of this on the car yet???

never complimentary? Was I too blunt to point out something that was deciving? I believed that you were the one that mentioned that the other benefit is you will have essentially a 76mm wastegate (directly quoted from your post) when you already knew that it only flows 54mm worth. If it was someone else that randomly posted that twin 38mm is equivalent to a 76mm, I probably wouldn't mentioned anything but a professional shop like yours should know better than providing false information to the public. In all honestly, I only simply said that it flows more like a 54mm instead of a 76mm like you mentioned knowing that you probably wasn't thinking about it when you type it in. Instead of saying thank you for correcting the error, you have to post another argument that you're still right. (6 to one, half dozen to the other) directly from you post. For your information, I do sell the kit as twin 38mm. (not 54mm worth, or 76mm wastegate). Also, twin 38mm wastegate doesn't flow better than a single 54mm wastegate. If you don't believe me, do the math or perform the experiment yourself and see if it's true.

Truth be said, I WASN'T thinking about it when I typed it, but I am not allowed to go back and edit posts and figured I would clarify it later. Far as providing false information or being deceiving lets not go there, but I did find it funny how quick you jumped on it. If I wanted to truly argue I would have said things more clearly earlier in the thread than I did so as to get you involved/steamed, drag you in, as far as the "always informative never complimentary ". It's true. Is that too blunt for you? You consistantly feel a need to jump in and take your little jabs, hey it's cool no problem, jab away. I prefer to stay out of your threads kinda like, nothing nice to say, say nothing at all. I think the word is....... respect(what I was using earlier in the thread), shows the difference between the two of us pretty clearly. I saw your newer version of your kit on a car it looks like you learned quite a bit from the first design. Good luck with it, really, I mean it, and so it is clear since I think we are arguing two different points. I never said it would "flow" better or worse than one, I said it would have greater valve to diaphram area than a 54mm gate which will offer better control than one 54mm gate, essentially this would offer control like a gate bigger than 54mm. , combined with a truly fully divided manifold and you get even better benefits. Let me know if I'm wrong, I'll gladly conceide the point, otherwise this is SteveC.O.D's thread and I'd rather let him have fun with it.

that is a very nice looking manifold.... i havent been in the rx7 scene for a long time but... i never heard of having 2 wastegates on the turbo manifold... to me... thats freaking cool... madd props dude

Actually, I probably wouldn't have notice this thread until someone called me and said, "hey steve, that manifold looks just like the turbo kit we sell". Even then, I didn't bother to post anything since it wasn't my place to criticize anyone's design since we all could have similar design in runner and positioning of the turbo. Besides, I was in Orlando at the time and doesn't have time to surf the forum anyways. It was later on when another person pointed out from your post and asked me if dual 38mm wastegate is equvialent to a 76mm wastegate and asked if that was the reason why we ran dual wastegate in our manifold setup. I told him that it doesn't come close to a 76mm wastegate (which is good for at least 2000hp) but rather more like a 54mm. In order to prevent anymore misconception, I figured that it needs to be corrected since you haven't posted anything for over an hr after your post. Besides, I don't do a search on a particular group of people just to read what they posted and if they were posting misconeption info so for you to think that I always attacking you is totally false. Like you said, this is Stevecod's post so I guess I'll end my post and let other people talk.


FYI, I don't have a newer version of the manifold, I designed two different manifolds back in october of last year for different spool characteristics and hp applications. We spend 4-5 months testing them before releasing them to the public. One apparently worked very well/supports the original calculations and made 474rwhp@19.5psi while the other is still questionable since we didn't have enough test data to support it. We have been selling the one that works since which is what everybody has in their car with our turbo kit. So to answer your question, we don't have a newer version of the manifold, its still the same and working well.

Ok,cool, I'm not here to argue with you on it. I hadn't gotten back to this thread in over a day at the time. The point I wanted to get across was control not flow, even flow can be questionable depending on wastegate position and what not, which you definatly saw with your first setup, when I saw your second setup (funny as it may be the same day you posted)at our BBQ, I was impressed with how similar it looked to what I had here. I'm sure it works much better, just by looking at it. I do not think you go out looking for threads, but I am very aware of your opinions.

*********** edited by Poweraxel for abusive language! **********

wow most of this stuff is uncalled for!
FDracer they have been civilized in their conversation and you come in dropping the f-bomb and calling names... not very mature in my opinion.
But back on topic Nice manifold none the less! if/when you dyno it post your results! That manifold is very similar to the one I have desinged in C.A.D. but haven't built it yet.

FDRacer:

sweet great post, way to make yourself feel involved!! i like the "f*ck" word makes you look smart.

Tisk Tisk.... Both Zero R and Pluto have contributed alot to this Forum and the Rx7 owners. Why does someone have to come on here trying to escilate things when it was a civil discussion? FDracer should be ashamed of himself.

How have you been?

I also agree that there might be an issue with controlling boost using 2 wastegates to control one turbo......something to do with the rotary exhaust pulses and the issue is greater when closer to the engine.

I've seen 2 identical examples which encountered boost control problems......both were later modified to fit a single wastegate. One with a HKS GT wastegate(60mm) and other with a HKS 50mm.....boost was rock solid !!!! even @ 35psi

alright....... alittle update on the setup. i installed everything already wired up the ltx-8s and started up yesterday. drove to the RS-R drift event to try to put some miles in the freshly built motor. 200 miles more to go until i can boost that BITCH!!!!! :D will let everyone know about the boost creep issue as soon as i brake in the motor.

steve

Nice work Steve, lets us all know once you boost that bad boy :)

*UPDATES* Please !!!