I finished installing my supercharger a loooooong time ago, and ever since I finished, I've been battling some serious issues. I had to replace one injector connector, and I was also dealing with serious ignition breakup issues. I have since replaced the injector connector, and I have installed MSD 8.5mm wires and HKS iridium spark plugs (10.5). Yet still, under WOT, once the engine reaches 2800-3000rpm, I start to hear a ticking sound come from the engine bay, which becomes more frequent until about 3500rpm, which I have not gone beyond. When I rev the engine under no load, it practically will not go beyond that 3500rpm mark. It only takes about 30% throttle to bring it to 3500, but then even under almost full throttle, it won't go any further. When I slowly raise the revs to about 3000-3500, the engine starts to misfire and buck a bit.

So, does anyone have any clue what could still be going wrong? Is there something in my ignition system, other than the plugs and wires, that could be weak and need replacing? Could by timing be off? Any help would be appreciated, as after over a month, I'd just like to have my RX7 back.

 

Alright, I'm starting to think it's the timing, because there's no way that 10.5 heat range spark plugs and 8.5mm wires can't provide adequate spark for ~200RWHP. Can anyone verify for me that this sounds like more of an issue with timing than anything else?

 

Ticking sounds can indicate an exhaust leak, but I have no idea how the ticking could really be something causing your problems. It's not detonation, that's for sure, because detonation is a ping sound, not a tick.

Why dont you just check the timing and see where you stand? Maybe you're way off and need to restab it.

 

Yeah, that could very well be it. I'll check into that. Most people I've talked to say it sounds like it's probably a timing problem.

 

Yah. It's always a good idea to check things like this especially when changine pulleys or doing major work, things can easily get screwed up. Believe me, I know My timing was so effed up after my rebuild even tho I restabbed it. Sometimes you just hafta put the gun on and make sure it's right.

 

Hmm, I'm going to check the timing, but could I actually alter the timing simply in the process of taking off the stock pulleys and putting on the new ones?

 

No. You have to adjust the CAS for the timing to be off. Where is your AFM hooked up? Are you sure it's actually functioning? Guess you don't have access to a wideband?

 

I hooked it up to a wideband, and it was reading AFRs from 9.8-10.4. It obviously wasn't reading correctly. My guess is that the motor was misfiring and actually dumping a lot of fuel into the exhaust, even though it wasn't getting enough fuel/barely getting enough. I'm not 100% on the MAF. Here's a picture of the angle it's at(please excuse my melted fan shroud):



I honestly don't know what it could be. Another thing that might matter is that the fuel pressure regulator doesn't have a vaccum line running into it, so it's linear rate for now (set to 60psi).

 

Anyone have any idea what it could possibly be?

 

Check timing, make sure your injectors are working properly, make sure your ignition is working properly, those are some places to start.

 

Maybe the belt is skipping? My friend underwent the same project as you and we heard a ticking-like sound. It was the belt skipping, but it was happening at higher RPM ranges. Eventually the motor blew so be careful.

 

That's odd. How could the belt be slipping? To tighen it up I stuck a 3-ft. long pry bar under the alternator and wedged it up, then tightened it down.

 

Even if the charger were skipping, it should still allow enough air through for the engine to rev. It's possible you've got too much fuel pressure at idle/etc causing the drops. What boost are you seing at the time this is happening?

 

By the time this starts happening, I'm around 5-6psi (~.4bar is what the boost gague reads).

 

Won't go above....3500. Have you confirmed those secondary injectors are indeed working? Can you swap injectors to confrim this.

 

The injectors are brand new Greddy 720cc injectors...can't see a problem with that.

EDIT: It has gone beyond 3500 when revving slowly under no load. I took it to about 4500 and it was still misfiring and dumping fuel into the exhaust. That's what makes me think it's something other than the secondaries.

 

i was thinking secondary injectors also since you said the engine is leaning out after 3500.


i just saw your note about the Greddy injectors, were they rated for high or low impedence and have you done the proper mods to support them if they don't match your impedence range?

 

Doesn't this seem like something other than a problem with the secondaries? I mean, I've revved it up past 3800 (to almost 5), but I this ticking sound just gets worse under load from about 3000 on, up until I'm not willing to push it any further. I've replaced the connector that looked iffy and I still have these problems. I don't understand, because if it was something regarding the secondaries, it wouldn't be a problem starting at 3000 that got worse as I approached higher revs, right? I'm going to check it with a timing light first to see what's up.

 

How tight is your belt? I'd try just taking the belt off and running it for a couple of seconds to see if it revs any easier, it is possible that A) your belt is too tight (serpentines don't need to be all that tight) B) the charger is requiring waay too much force to spin (oil supply issue maybe?) Fuel just seems to be a hard thing to imagine causing that much breakup, are you using an S-AFC at all? What are your settings?

 

I am running my S-AFC rich 10% all the way. I am also sure that the belt is fine because I contacted Gary and he told me that tightening the belt with the alternator (as much as possible) was the best idea.

Tomorrow I'll check the timing, and if the timing is on, I'll check the MAF sensor. If the MAF sensor is screwed, I'll just go talk to Chris Greene and get a Wolf 3D.

 

I checked today and the injectors are 2-3ohm resistance, so that shouldn't be an issue, correct?

 

What injectors are you running again? And what year car?

 

Have you verified your S-AFC settings are correct? What you might consider doing is bypasing the S-AFC and seeing if it has any effect. What are you running for primaries?

 

sounds like detination to me. Make sure those injectors are the right impadence for the car.

 

720cc Greddy Peak/Hold on an S4.