Single set-ups don't have to be expensive when u know what you are doing and working with. Most people just buy, buy and buy till it's done but when you break down exactly what you need and shop accordingly then it's always alot cheaper. Good luck and I'm in for your results!

 

**UPDATE**

New photos, it's complete, and it LIVES! Seems to boost nicely at 10psi, though further attention is necessary on a dyno.

 

Good job, man! Since I'm just getting into this conversation, I get to avoid conversational deviations.

How much efficiency have you noticed vs. the stock twins?

Keep us posted on how things are going!

 

Well actually I should have mentioned that. It actually starts to build usable boost at around 3100RPM (much lower then parallel twins). It reaches max boost by 3900rpm, and from there it's angry, and sudden power. (I personally love it) It's very predictable though, the open waste gate sounds amazing. The turbine intake is very pronounced, and the SSQV BOV sounds great also. I'm very happy with the swap so far.

I've posted a video. Mind the crappy quality, it's from a blackberry.

http://www.youtube.com/watch?v=L9ZrxuExz50

 

I wouldn't have believed it if i didn't hear it start for the first time.

 

That u Kris? LOL

 

Good stuff man! What intercooler is that?

I think these cheap-bastard builds sometimes get a bad rep because people will do them attempting to build a car just to have a cool car on the cheap. I think your project will (is) succeed because you know what you're getting into....I hope that made sense? Haha

 

Its just a cheap Ebay intercooler from kazespeed i got it for 115 bucks I think + shipping. It says its for a second gen RX-7 but it fits so good.

 

Are you planning to do any duct work for that intercooler? What kind of intake temps are you seeing?

 

I'll be fabbing a duct myself when I get around to it. I'm confident that even without a duct its a good step up from the stock IC setup.

 

I am doing an identical build except with 3 1/2" spacers. Same everything else, going on a S4 6 port. Megasquirt taking control.

 

Should run well, I've heard bad things about megasquirt not being able to keep up though. I would use a powerFC if you can.

 

Just a quick question... Did that manifold start out with a rectangular waste gate flange, roughly 46mmx66mm?
I have yet to see a waste gate that will fit that manifold as is.

 

Not sure what the dimensions were. but the HKS 50mm bolted right on. All I did was open up the flange outlet on the manifold a bit to match the 50mm waste gate instead of a 46mm.

 

I disagree with the above. I'd look into installing a duct as soon as possible, with minimal air flow that is worse than the stock setup.

Keep an eye on those couplers too, are those the ones that came with the IC? They look to me like they want to blow off, Samco couplers aren't exactly 'inexpensive' but they won't leave you on the side of the highway either

 

I have been thinking about this lately, wondering if the 'cheap' ebay IC's are an improvement over a stock one all else being equal.

 

These are just straight silicone, but I haven't had any slippage at all, a pipe blowing off isn't really that big of a deal, you're not stuck on the side of the road, ur just stuck without boost.

This IC has over 5x the volume that the stock one does, no doubt in my mind that it's far superior than the stock FD IC.

 

one more question...
What waste gate did you use? You were doing this project inexpensively so I would assume that you did not spend $500 on a 50mm waste gate.

If you purchased your waste gate from ebay as well, I would like to know if it's working out for you.

 

just re-read your reply to my first question....HKS
cheers

 

HKS "Style" it was 104 dollars shipped, and it works very well. there are actually 10 and 5 psi springs available of it by searching "wastegate spring" on ebay.

I've has an HKS and this one side by side, and they are identical in every way, internally and externally the only difference i can see is the HKS has a smoother casting. if you care how your waste gate looks, then buy an HKS for the extra 400 bucks. xD

 

Hate to be the voice of reason here but just because they look identical to you doesn't mean that they are identical. I won't install knockoff wastegates on customer builds.... they're an important part of a robust turbo system

Anyway, best of luck on your build. It looks like things are coming together for you, but remember: just because something works for one person for a period of time doesn't mean it's a consistently repeatable result.

No pissing in the cheerios, just wanted to give an alternate viewpoint

 

I had them apart in front of me, the shafts and seals are the same size according to a caliper, the only thing i would say might be a weak point is the diafrahm itself. lucky for us a real HKS one is cheap.

 

I had an HKS knockoff 50mm (came with some other parts I had bought) but I was too sketched out to use it. I've also seen a knockoff Tial 38mm fail right out of the box.

You may have gotten a good one though. I've seen and worked on my share of cheap bastard turbo setups on piston engines and the things that always seem to fail are the cheap couplers and cheap turbo manifolds. It's interesting how you replaced the CHRA on your turbo, when in my experience that is the one thing I don't normally see fail. It's mostly manifolds and to a lesser extent wastegates.

 

I was told the fins wouldn't handle the heat from a rotary and rotational speed combined, so i just got rid of the one part of the turbo that could fail.

I haven;t has any issues with the waste gate, it opens nice and smooth and seats well, he only thing i could imagine failing would be the diafraghm like i said before, the rest is dead simple i don't even know if anything else can fail.

 

That is what I would think on first blush butttt....I was talking to a rep for high price (= quality???) ICs' at the Walter Mitty Vintage race this weekend. And I was thinking about your build and I asked what he thought the difference was between "ebay" and quality ICs. The answer is probably posted here a million times but it was news to me.

He said that the passages on cheap ones are small in size and inefficient at transferring heat....but mainly small.

The small size causes pressure drop. So all that good boost your turbo is making is not able to get into your motor.

On top of that the stock one is ducted a bit so it cools the charge while yours would be quickly heat soaked further lessening the charging effect.

I dont know how restrictive the stock IC is but I think you get my point.

I would probably do exactly as you have done but it is worth thinking about on a future build....all things being equal might be worth sticking to the stocker until you.....find a used quality one cheap :-)

Which takes me to another point that I am sure has been discussed here alot.

if you have a restrictive IC would it be better to put your BOV between the Turbo and the IC so you dont back up the pressure into the turbo as much? does it even work like that? Would it just sit there partly open a lot because of the back pressure caused by the IC and cause running issues?

I have seen BOVs mounted before and after IC (usually after) I will have to read up on why that is.

After playing with NA cars for years I am really starting to see the intrigue and mystery of the turbo.

If F1 goes back to Turbo in a few years it will be interesting to see where turbo technology goes. Will it have some significance to street cars or will they go in some crazy direction that only has application at 25000 RPM and wide open on a race track....but I digress....any way fun stuff.