Okay here is my situation. Its been a year and a half since i intalled my new engine. I have very healthy vacuum. (-44/45cmhg). The octane rating in Bangladesh is really bad. Maybe RON 90. Survived this long and always counting days.

I have a dp (1998 model) , knightsports Hi-FLow CAT, a custom end. I have a SARD BOV......other than that everything else is stock. I use the stock air filter. Have changed the fuel filter. Have been using synthetic oil (Mobil 1) for the last 1.5 years. My Mazdaspeed AST is on the way, i have bought a KOYO radiator. So that should take car of the reliatbilty mods. (will do the fan mod).

I have seen boost peak at 10.80psi (max. can it be because of the newer ECU in the 1998 models? or maybe for my exhaust setup)in my blitz boost gauge as well as in my blitz DTT. Does anyone know what my boost pattern should be stock??

The thing is, i want to run 7psi boost max. That is 7-5-7 pattern. I have read about removing the pills. My question is, is there any connection i can unplug to get 7psi max boost(without taking out the pills). I did read it somewhere where rynberg said its possible to unplug a connector from a solenoid. However have been looking for that thread the last couple of days, but invain.

I dont want to buy the profec B 2 and keep it switched off to achieve my 7psi boost. (Or should I??)Can someone explain about the timing thing. How can i retard it?? Sorry for the dumb question. But please do help. I want to be as conservative as possible.

Also, does anyone have a write up on how toulene can be mixed?? Meaning is it only toulene that you add or something else as well along with it( not asking about MMO or premix)?

I'm here on the forum all the time, reading up. Always see people blowing engines, and with my situation and lack of resources, I dont know how long i'll last. GOD help me.

I have nightmares at times and bad dreams. (I SWEAR).

So please help me.

Best regards
tahmid

 

Err..wtf are you talking about ? You wanna turn down the boost level ? The transition boost should be 10-8-10. so 10.8 is really just a small spike . You could try damian's boost controller setup . go look up on some of his threads.

As for toulene , it is just to add to the fuel tank after you pumped gas in to try to increase the octane rating . there are other things you can add other than toulene.

 

http://home.cfl.rr.com/eskram/toluene/

that after 2 mins of search .... dude you really should try other wordings

 

Did you notice the octane rating we get in our country. I wanna play safe.I can understand its only a small spike. However i dont wanna keep on boosting 10psi with the octane available.

 

Thanks. This is very helpful.

Can anyone help me on the timing or boost issue??

 

What octane is available?!

-Alex

Edit: Nvm, I just noticed you stated 90 octane. In Cali. they get 91 octane, so I don't think you have much to worry about as long as you keep the boost at stock levels.

 

Alex, you guys get 91 (RON+ MON/2). I get RON 90.

 

bloody hell we get 98 over here in the uk...

 

Ron 90 is probably equivalent to 87 octane, as measured in America, so yeah, not so great.

As far as removing pills, it's possible you don't even have pills and that the restrictions are in the turbo housing nipples.

The rat's nest on later models (post-95) is different than the 92-95 models, so I don't know if this will still work. You can get 7 psi by unplugging the electrical connections from BOTH the wastegate and pre-control solenoids. These are the two large solenoids at the front of the rat's nest and UIM.

 

I was so hoping that u'd post here rynberg. Thanks.

Thats what i wanted to know. If i dont have the pills (i'll look anyhow). I'll take pics of the UIM removed and the solenoids there. PUMA posted a while back, the differences. If that too isnot possible. Should i just buy the Profec B 2 and intall it. Then maybe keep it switched off for 7 psi. what do u think rynberg? Is that possible? I'll check on the wastegate and pre control solenoids. Thing is if i leave them unplugged, will it harm the 7 in any way??

 

I know the rat's nest is different on your 98, but I wouldn't be surprised if the pre-control and wastegate solenoids are still there out front. No, disconnecting them shouldn't hurt the car in any way, you are just preventing the ecu from operating things, that's all. Your boost will not be as responsive, however.

To be honest with you, I would invest in a boost controller with multiple settings. Instead of turning it off, you could just lower the settings to close to 7 psi -- the boost response should be better. Then, when you run some additives to raise the octane, you can easily raise the boost simply by changing a setting.

 

I found this in a Japanese site.

91.12-95.7---boost pressure 400mmhg (0.54kg/cm2)
96-98.11 ----- boost pressure 470mmhg (0.64kg/cm2)
98.12----------- boost pressure 560mmhg (0.76kg/cm2)

http://13b.power.ne.jp/main_contents/index.html (just scroll down)

I think thats the stock boost level. Correct me if i'm wrong.

 

Thanks Rynberg. Then thats what I will do. I'll buy the profec B2 asap. Can the boost be set at 7spi using the Profec ? How diffuclt is it to install and tune?? I have the links to the last few writeups on it and reviews.

https://www.rx7club.com/showthread.p...=profec+tuning

But I want to know from you.What are ur thoughts? I can tune it for maybe 7spi LOW and 9psi HIGH. What about the gain setting. You have to help me set it up, once i get it. I'll need your help. Please.

Rynberg, do you think I shoudl get water injection?? Am i going all paranoid?

Thanks
Tahmid

 

Well, if you are only getting 90 RON, you are right to be concerned, but the situation may not be as bad as you are thinking. I'm not sure about your 98 ecu, but the 93-95 US ecus were very rich and had conservative timing. They also used a knock detector, so you should have a little bit of cushion there if the 98 ecu is similar.

I don't know anything about setting up the Profec B Spec II. I have the original Profec B, which is now the Profec S. You should be able to turn the boost down to 7 psi no problem with either.

Water injection will also lower your chances of detonation. I would look at one of the single-stage kits from Cooling Mist (www.coolingmist.com), David will set you up.

 

Thanks a lot. I'm going to go through the cooling mist site. Should I get the Deluxe or Base single kit? The 98 ECU is also runs rich and uses a knock sensor. Dont know about the conservative timing though.

My supplier in Japan also suggested that I should get better spark plug wires and ignition system. What are your thoughts on that??

So the things I should do is basically:

1. Get a boost controller ASAP. ( profec B Spec II)
2. Get a cooling mist single stage kit

Did you see the post about the stock boost levels. Why do always people say 10psi. 1991-1995 it was a little more then 7.7psi?

 

If you're concerned with pinging and detonation with RON 90, and the car is running well, upgraded wires and plugs will only ensure you burn fuel more completely which may take away your small safety window. As long as you aren't having starting issues or surging when cruising, maybe replace your plugs with a lower temp range to decrease your chances of hot spots being caused by hot plugs.
If you have access to the Profec S(new style profec B) I would recommend that one instead of the B2. I have installed a few B2's on 3rd gens with highly variable results(ie not consistant boost). I have a profec B and I believe Rynberg does also and I think he'd concur that it is a very simple install and it is very straight forward without a lot of extraneous (read: useless) gadgetry to set. I believe RP in Texas has these in stock. Just some friendly suggestions.

Art

 

You might just need the mist kit plus may be some additives in the tank ... The cooling mist kit is know to drop detonation numbers . As for ProfecB mm...you could get it .
Well that what i think any ways ..

To each his own ...

 

Why not just unplug the wastegate solenoid so that the ecu doesnt duty cycle the boost up to 10, instead letting the WG spring alone control boost to 7.

 

You wouldn't need to waste money on a boost controller in his situation, if you do what rotaryres said the ECU won't even allow the boost to cycle to 10 lbs. Spend the money elsewhere instead of a boost controller especially since he never plans on running any kind of high boost. Even if he spikes past 7, worse comes to worse he'll only hit stock boost anyway...

 

1. Personally, I would get the new Profec-S, like RTS3GEN suggested. It's simple to use, simple to install, and it works.

2. Talk to David about which kit you should kit. I really like his new style kit without the solenoid. It uses a check valve instead, which reduces the chances of failure and simplifies the install as well.

Your source is wrong, the stock boost on the 93-95 cars is about 10 psi, or a hair less. Later cars supposedly run 11 psi stock. Perhaps your source was wrongly quoting the wastegate opening pressure?

 

Thanks Art for the insight. What heat range do you think i should be running?? I have absolutely no issues like starting problems (both cold and hot) as well as no surging issues. I guess i would get the profec B since rynberg has it and you guys can help me with the installation procedure. I believe installation isnot all that difficult.

 

DP

 

RotaryResurrection, thanks for your reply. I want guys like you to comment and help me. Is it only the wastegate solenoid that I would have to unplug?? Then I would do that till I buy the Boost controller. Do you think buying the boost controller is a waste of money, in my case?? If so, why??What are your thoughts on cooling mist? Dont, you think that will help me. I have already looked into a getting toluene. Hopefully I get to know by today.

 

nopistons94: Yes, I never plan to run any high boost. Is it possible that the boost my spike with the wastegate solenoid open??

 

Rynberg:

1. I'll buy the profec-S, since you guys think it works better and is easy to use. However question is, why does RR think I should just unplug the wastegate solenoid? Is it possible that boost will spike past 7spi with the solenoid open?

2. I already e-mailed David a couple of times. And man, he is so prompt with his replies. He seems to be a great guy. He suggested the single stage kit for me. Ihave already e-mailed him wanting to know about the system which uses the check valve. Installation of the cooling mist seems to be easy as well.

3. Sorry, I was wrong. However got the info from a Japanese site. I attached the link. Sorry about that.

Rynberg all these people in Bangladesh are driving their 760s and 5 series, mercs, porsches with this octane. I guess its only a matter of time before they start suffering. You guys are very lucky to have all the resources and right tools. We dont even have a dyno in Bangladesh. I want to buy the wideband O2 in the future. Do you think would need that?? What about techtom? Seems like a good thing. All live data from the ECU.

Best Regards
Tahmid

Thanks to ALL for their reply and hep.