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Discussion Starter · #1 ·
I am currently looking for a manual boost controler. Does anyone know of a good one (Including location and pricing)

Also, I plan on custom building an exhaust. Should I go with 2.5" or 3" Piping? I know I dont have to worry about back pressure but what would be a reasonable suggestion? Should I leave out the Cat or buy another one or reuse the old one (I live in Florida so emissions are a problem)

I am also looking for a high-flow muffler that doesn't look like a ****ing riced out coffee can. I'd prefer to keep my car as stock looking from the outside as possible.

Stock boost is about 7-8 psi. The engine is completly rebuilt w/ less than a few thousand miles on it. Without any current upgrades (CAI First) what is the maximum boost it can take and what should I set it at realistically?

I have a 91 Mx6 running 195/70R14 w/ brand new tires. My 626 is running 195/60R15 with almost bald tires. I prefer the Mx6's rims over the 626 but they are 14s. Would the 14's throw off my speedo much or should I just buy new tires?

Thank you for any help
 

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Hey, fellow 626 hatch owner. First off, for a boost controller you cant beat what's known as the "dawes device". It's $35 and works excellently. I have one myself and am quite happy with it. You can purchase it at www.dawesdevices.com. As far as tires are concerned, buy another set of 15's. The handling response is better with the lower profile. I suggest a set of Bridgestone RE950's, pretty decently priced and nice performance. As far as an exhaust 2.5" should be sufficient, but you can go larger. I just dont know much more there is to gain with a 3". For a muffler, dynomax makes some pretty decent mufflers that arent ricey looking. For the cat, I would take a look at the Random-Technologies cat. Manifest has one and probably would be able to tell you more about it. But I hear they work very well.

Now the big question is how much boost it can take. When I had the stock turbo, I was running 14psi on my then 163k mile stock motor with no trouble at all. With my upgraded rx-7 turbo, I run about 12 but have run 15 a couple of times without any trouble. I would say with an engine in excellent shape. 20psi shouldnt be a problem provided you dont detonate! So plenty of fuel is advised when going that far. Which brings me to another point. In order to run past 12psi, you either need to get a chip or to modify the airflow meter. The most you should ever run on the stock turbo is 15psi. After that it really loses efficiency and can get damaged, not to mention it's just blowing heat at that point. Trust me, when you feel it at 12psi you'll be satisfied for a while :).
 

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Discussion Starter · #3 ·
Since the turbo is original I dont plan on putting it past 15 psi (12-13 sounds good) What is the deal with a new chip? How much would one cost and from where? When you said you could also modify your airflow meter was that an alternative or requirement? Is there a site which goes indepth on modifying the airflow meter that could assist me? I dont want to spend a whole lot of money so would it be adviseable to replace the cat with a straight pipe?

I want to purchase a Boost Gauge to monitor the turbo but I've heard some about a EVC. Would that be a better alternative over the manual boost control and would there be a large price difference?

If my turbo happens to go at some point, what other reasonably priced alternatives would i have over buying a used OEM Turbo?

Also, w/o changing the internals on the turbo, could I decrease turbo lag atleast slightly? Taking off in 1st doesn't present much of a problem with practice but comming off corners in 2nd gets ggervating until 2500-3000 RPM.

I really appreciate your help Anarchy
 

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Well, a chip does a few things. Firstly it allows you to run more than 12psi of boost (stock ECU cuts fuel at 12), plus it optimizes fuel/timing for more boost. I decided to take a different approach. I modified the VAF to prevent boost cut (drop me an e-mail if you want to know how), and I used a rising rate fuel pressure regulator to supply more fuel.

A boost guage is about $40, and is a worthy investment. The HKS EVC has a boost guage in it, however it reads in BAR and not PSI. The EVC is an awesome device, but the cost difference is high. The EVC goes for around $600. Big difference :).

As far as a replacement turbo, there are a few alternatives. One is the T-bird turbo, which is a direct bolt on, and flows more air, which increase high-end power. I have what's known as the RX-7 hybrid turbo, which is a little bigger than the t-bird. It cost me about $650. The T-bird can be had for much less though. There are a few other options such as a ball bearing WRX turbo, and a T3/T4, but those are a bit more money (at least $1000). Also, I dont know any way to modify the turbo itself for less lag, but once you improve exhaust and intake breathing, lag gets reduced. You just have to get used to it. Once you know how to work around it, it's not that big of a problem.

Just curious. What color is your car?
 

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Discussion Starter · #5 ·
Sounds good, I'll e-mail you later on that. My car is a dark maroonish color. It wouldn't be a choice of mine if I had one, but its not too bad looking. The person who had it before me never waxed it so the paint on the hood and roof is faded alot. I'm sure a good waxing would help.
 

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Discussion Starter · #7 ·
Ok,

Since I am young I dont have alot of money to spend. Some things I was wondering about is exhaust. For the money I would spend on it how much of an increase would I be looking at? In the near future I will have access to two local garages that I could custom run 2 1/2" to 3" straight back to the muffler. That I am not too worried about. Headers and muffler is what I dont want to spend alot of money on if it wont bring a significant increase (under 5hp). I have heard people talk about the Dynomax Turbo Muffler sounding good but not really providing to the performance aspect of the car. Looks are the least of my concern here since the car is kinda raggedy already. I know there are a limited number of parts available for our cars and one company that makes parts are Pacesetter but all I hear about these products are, well, let me just say "Paceshitter" Also, what is a good reconmendation for intake? I know a cone filter is out due to the heat generated by the turbo. I have a K&N Filter right now. On my 91 Mx6 I ran 2 1/2" vacuum hose from the intake on the stock air box through the engine to the front of the car (No scoop, I just never found anything that seemed it would work, maybe becuause I never looked:rolleyes: ) Another thing (Sorry for the long post) is my turbo has 184k on it (rebuilt engine) and I would be worried how much it could take in its condition. I want to run atleast 12-13 psi. To acheive this I need to modify the airflow meter but I dont want to make anyone type out indepth details so is there a FAQ floating around anywhere that could help me out. Sorry for asking so many questions but I want to be well informed so I dont accidently **** this car over. For the time being, I am going to order a Dawesdevice and a boost guage and set boost to 11psi so the ecu wont cut it, Oh yea, and get some new tires (The originals are starting to dryrot...)
 

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I think its like 30-40hp increase superchips was saying. So you should be able to hit around 170-180hp. But your torque is going to go above 200ft-lbs so its going to pull like crazy!
 

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Discussion Starter · #10 ·
Man I wish you could see the grin on my face. Boost here I come! That is if my car checks out ok. Hopefully it is just a busted coolant tube...
 

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anarchyx34: Boost meter for $40 where can I get that, I need one that's under $50 (I don't have much $$$) that dawes device is really cool. Maybe we should make a FAQ on how to install it (I still need to get it)
 

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www.summitracing.com sells autometer guages. They also sell VDO guages, which might be more worth it for you since it only costs $28. The catalog # is VDO-150206 (I have the catalog in front of me). VDO makes an excellent quality guage. As for mounting, you can get a pillar pod, or just velcro the guage to the dash, up against the a-pillar. That's what I did for a while and it looked fine.
 

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The chip doesn't get you much more HP, (but there is some due to timing and fuel modifications) it is there to allow you to run higher boost safely and eliminate fuel cut.
 

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I noticed a little more power when I tried a EL prototypes chip without changing the boost setting. it seemed, I dunno to pull "smoother". Like the high RPM drop off didnt feel as severe.
 

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Hey guy'swhat about the ferrari F-40 turbo upgrade is that any good or does it suck?The reason why i asked because when i purchase my 6 that's the way i plan to go.
 

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Wayman was pushing 200+ at the wheels with that turbo.
 

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you need the boost meter more importantly.

With out it you wouldn't know how much you are boosting!!
 
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