Blueman33

MY SWISS,

no one answered my question on the CV. Does the original have to be replaced as SeaCay stated and is the $34 part listed above at Paragon the correct one??

thanks

adampad

A good ball and spring MBC will wont bleed boost until the last second.

All you need is a cheap ball and spring type MBC from ebay for about $15. You can get VDO boost gauges for like $25 from summitracing.com. They ship superfast too.

MySwiss

I bought one of those cheap ball and spring boost controllers. The word cheap , best describes the product..........the spring would get jammed all the time, boost waserratic and the garbage can loved it!!!!

When I tried Edman's Profec B,I instantly noticed the difference. Instead of hitting full boost at 3850rpm, I got full boost at 3100rpm. That was enough proof for me ,to feed the garbage can.

adampad

You should have just got a spring that fit better. I've never heard anyone with that complaint before. Just because they are cheap doesn't mean they are not effective. If installed correctly it is impossible for boost to be erratic.

MySwiss

How does the installation affect the spring, when all you have to do, is connect 2 hoses to it??

Some of these boost controllers are privately machined with a utility drill, and leave all kinds of burs for the spring to get caught in. Now, I might not be Einstein, but there is certainly room for improvement.!!!!

After all ,the Reliaboost can not be considered an expensive unit But it certainly works better (with the right spring).

"I've never heard anyone with that complaint before"

I never heard anyone complain about the Profec B spec 2, being erratic. But , all it takes, is one person to start sharing, and you get the ball rolling.
I thought I was the only one having setting problems with my Profec B spec 2,but after posting , I find out there's more.

porshhhh951

adampad....I like your car....and let me be the first to welcome you to the rennlist board.

We are kinda like family here....and most people on the board do all there own wrenching. We are a knowledgeable bunch....and you won't find a better source for your info. We also..pride ourself's....on being above the hole internet **** talking thing. You will like it here I promise.

I had a friend with a 92 model turbo mr2...and I think it look's like a little ferrari! I love it. Anyways just wanted to say welcome to the community
and sense you are turbo
welcome to the boost addiction

take care,
john

adampad

It can still be messed up. You could install the wrong end to the wastegate, or you could hook it up to a non-pressure source, etc.


I have to admit I havent heard of the Edmans before. When you say Profec B I think of Greddy. What is Edmans? I would love to have a nice EBC but the cost is out of my range. The only pro for one in my opinion is that it would be adjustable on the fly. If thats worth $300 to you than go for it.

I doubt they will be too many if any complaining out a WELL MADE MBC. I got mine from Ebay and it works great. I did have to trim the spring to get lower boost setting though.

John, thanks for the welcome. My little brother just got a 85 944na. It needs a little TLC and I've been coming here for some advice. He doesn't even really like it, but it has grown on me a little. I hated the car at first, because the lots of little things didn't work, and it seems to be a pain to work on. Anyway, I love my two. It is a turbo and is so much fun everytime I drive it. But the 944 thing has bitten me. I am very interested in the 951's now. The one thing that turns me away more than anything is the cost of parts.

SeaCay

Adam, springs are a linear device. For a MBC set at say 15 psi of boost, it WILL start opening well before 15 psi. That's the nature of the beast, it doesn't matter if it's made of unobtainium, it's still going to work like that. To work like you state, the spring would have to have a reverse progressive characteristic.

Then again, don't believe me, read what the recognized turbo guru Corky Bell has to say.

Ben Z.

Blue- You've already got the LBE; it can be made identical to the reliaboost by drilling a single hole. That's what I've done and my boost level doesn't vary more than a half psi.

BoostSciences

To: MYSWISS

I noticed you made a comment about "cheap" boost controllers having problems with the springs jamming and burrs on the inside etc. Were you suggesting that the ReliaBoost has these flaws ???

To date, we have not received even one complaint regarding the workmanship on the ReliaBoost and AccuBoost controllers. Also, both these units are machined and definitely not drilled. The AccuBoost is machined to 0.001 inch tolerances using a CNC mill, which are hardly achievable on a drill press. Also, there are certainly no burrs present, and definitely no issues whatsoever with a spring jamming.

Maybe I have misunderstood what you implied but your clarification would be most appreciated.


To: BENZ

Yes, you are correct that drilling a small hole in the LBE will make is more like the ReliaBoost, but it is not identical. The location, size and complementary response mechanism all work together to make the spiking problem better or worse if used incorrectly. On another note, the RB has a much faster response mechanism when compared to a poppet like design of the LBE and the RB is all metal in construction, the LBE is not. The LBE has plastic components and as we know, plastic + heat do not mix well. Not trying to make a point, just stating the differences FYI.


Thank you.

Ben Z.

BoostSciences-
Good to see you joined Rennlist! I made a mistake by using the word "indentical". I just noticed that the guy already had an LBE, maybe he could save some cash for a boost gauge or whatever. My LBE still functions fine and the plastic inside looked brand new after about 3 years of use. To be honest with you I probably would have purchased the RB if I knew about it back then due to the significant cost savings. As a side note, would you be willing to share the results/methodology of your testing that shows the faster response of the RB vs. LBE? I'm sure many on here would be interested.

Thanks

adampad

You are correct, I shouldn't have said hold till the last second. But I bet 99.9% of drivers couldnt tell the difference between a good MBC set at a given point and a EBC at the same moderate boost settings.

Maybe a very high boost levels +25psi maybe a difference would be noticable, I dont know. All I am saying is a good Ball and Spring type Boost controller is the best bang for buck.


By the way guys, what size are the stock 944 turbos? When do they start spooling stock? What kind of boost can they hold till redline?

MySwiss

BoostSciences . You got me all wrong. Read my post again. What I'm trying to say ,is that the Reliaboost, even though it's affordable, it functions right. Whereas the e-bay (brass) boost controllers (I bought one), that sell for 20$, are the ones I was referring to. These units have caused me and a few friends of mine, some head aches.

turbo944

adampad,

What size? Not sure if you mean dimensions or type of turbo, but the stock 944 non-'S' turbo setup is a K-26/6, of which I have flow charts in my Rennlist gallery for at http://gallery.rennlist.com/gallery/turbo944

My turbo (see my sig for current mods...my Guru chips were shipped yesterday so I expect a bit more power/better a/f from them) is stock and I can be at constant speed at about 2500 rpm in gear and push the throttle to the floor and I have boost by 2800 and am at full song by 3100-3200rpm. I can tell its way too rich right now as at times it can send a good bit of black smoke out the tailpipe. I hold strong boost at 15psi and then a slow drop as it approaches redline, which is pretty well what is predicted for that turbo.

On a side note, I've noticed you have a nice looking MR2 turbo yourself. My brother has a 91 NA that he's wanting to turbo, it got hit recently in the rear end (end cap/bumper cover is broken, dent on fender there and taillight knocked out of place). Are you a member of any MR2 group or know of anyone who might have one they are parting out that has a rear bumper cover? You can PM me if ya like.

adampad

Turbo944, thanks for the info. It sounds like you guys could really benefit a lot from a little larger turbo. Are you saying you guys run around 15psi stock, without some form of boost control?

As for the MR2 bumper, it might not be too tough to find because they are lots of imported rear clips. If you brother wants to go turbo, I suggest he buys a rear clip.

Here is a link to the MR2 boards parts swapper section: [URL=http://www.board.mr2faq.com/forumdisplay.php?s=&forumid=85]
Post a WTB thread and Im sure someone will have what you are looking for.