Hi all,

Just bought a TII, the motor is a 88 Jspec 13BT got from Japan2LA less than a year ago, the motor are having about 120psi all around per rotor according to the seller. The car got Rtek1.7, 720 pri 890 sec and SAFC.

Now here is my puzzle, it only got 12 mmHg on the Vaccum reading. The car starts rough no matter cold or warm, loping on one rotor and rpm fluctuates, with a little gas it sound better, and when it is warmed up, it idles great and smooth about 1000 rpm. The wideband reading is about 11 to mid 12 during idle and around 14 and 15 when cruising. The car hunts and backfires at shifting and particularly decel. The butt dyno don't tell me this thing got about 300HP as it is supposed to be ... it got a BNR stage III and all the goodies for that.

Can anyone give me some advice on where to start? I am thinking about giving it a compresion check, and anyone can recommend a place around Minneapolis? I have found the instructions on adjusting the TPS for gen III, does it applied to 2nd gen? Are there any instructions on tuning the TPS? The car got a lot of utilities to play with I want to get it running right and have a lot to learn. Thank in advance.

Oh, the motor got ATK tags on it, so this actually rule out the motor is ported, right?

With regards

Xiaonan

 

just do the poor mans check, take out the trailing plugs and then have someone turn it over, you should get 3 even puffs on both rotors, in not then youve got bad seals

 

sounds like it needs tuned, and i have no clue why you're using 720 primaries, thats wayy overkill especially with an SAFC that cant do all that much as far as tuning is concerned.

 

I would check compression with a tester, and replace those 720 primaries with 550's or move to stand alone A stand alone is a good idea anyway with that BNR turbo on it

 

ditto, the primaries are what is causing the problem.

 

Well, I didn't quite get why the previous owner, put in the 720 pri. He explained as that was the only way to get it running from leaning out ... and he had 550s to begin with and had problems. But now it runs about 11 on f/ar at idle. The wired thing is, as far as I understood from the conversation, he had 12 mmHg of vaccum from day one without the injector mods. I will go look into getting a poor man's compression test first then.

 

vacuum doesn't always mean a whole lot, compression is where problems can easily be seen.

vacuum usually is dependent on engine speed, if the engine is only iding at 600RPMs then i would actually say that is rather good, if it is only 12"Hg at 1200RPMs then you may have low compression, generally if it is 14"Hg or higher at 900RPMs then i don't worry about it as there are many variables like porting and intake/exhaust that can affect the numbers.

 

First thanks all for your inputs.

OK, I made some progress today. I adjusted the TPS, it originally was running at 2K Ohm, I set it to 1K and the rest looks ok. The idle kinda settle down a bit, but it even get's richer, AFR about 11 now at idle, this could be due to the previous settings in the SAFC and the 720 pri. I have never used SAFC before and need some reading and learning on this, could anyone give me a link for this?

Then I checked compression with a piston compression tester. With throttle to the floor I got even bounces on both rotor and they all scored about 100 psi for the max compression.

Now with the TPS set to 1K at idle (about 700rpm now, 1000 rpm before), the vaccum even got lower, it is at 10 inHg !!!. The vaccum/boost gadge is hooked to the UIM and T-ed to the BOV. I don't quite know what to do next. I got a bottle of starting fluid, and should I start to spray and check? I couldn't hear any intake leak though.

There is also exauhst leak about the turbo that I can not able to locate exactly. I think one of these weekends I will get a set of gasket kit and redo the exhaust. Any suggestions on what gaskets to buy? The turbo is BNR stage III.

That's it for now, thanks again for all your inputs.

-X

 

BTW, I want to clearify that, the previous owner of this car did an excellent job, and the car is awsome. All I am doing now is to finish up the tune-up and make sure it runs at its potential. I am quite lucky to get this car, and the seller (Slick) is a great guy.

 

SO SO SO SO SO much better!!! I couldn't belive a TPS adjustment made the car so smoooooooooooth!!! No more hunting and backfire, decel is great!!!!! Still more to improve!