Ok, I can already feel the heat from the flames coming.... We just completed a full exhaust on our 94 today. Downpipe, midpipe, and Racing beat cat back. Only other mods are manual boost controllers, and Spec Stage 3 clutch. Don't worry, I haven't full throttled it yet. I did have it about 75% though once and it made a big pop noise. Figure that's no good eih? lol... still runs fine though. So my question.... The a/f gauge shows we're running pretty rich with the thing... So why is it that we need an aftermarket ecm? We put on an HKS Super AFR today and plan to go to the dyno on monday to get it dialed in right. Wandering if that's going to be enough, or if we need an aftermarket ecm for any other reasons? Boost is spiking pretty bad for obvious reasons. Gonna have to tweak the boost controller a little bit to get it down to a more tolerable level. Right now it'll hit 15 lbs if I'm not careful. Kind of scary Want to get it back down to something like 11-12.....

Anywho, let me know what you all think. Please be as detailed as possible.

Thanks
Chuck

 

Damn. You're gonna kiss your motor good bye.

 

The motor is not gonna go now just because he did that, it's not gonna help the life span but its not gonna blow it NOW. Check the a/f with a wideband and keep boost at 10psi..you will be fine until you do get a ecu..Its a ecu not a ecm...

 

You don't need an ecu IF you can actually keep your boost to 10 psi and avoid spiking. That may prove impossible without porting the wastegate or introducing some kind of exhaust restriction. The stock ecu employs a fuel-cut when it detects an overboost. The overboost level varies but above 6000 rpm, it will cut at 10.7 psi. This is bad.

Also, even though the stock ecu dumps a bit of fuel at the transition, if you spike bad enough, you will run very lean whenever it happens. All bad things.

Don't be cavalier about your engine. If you don't want to spend a ton of cash, atleast pick up a used Pettit or M2 modified ecu. Or take the midpipe back off.

 

ecm, ecu, pcm.... everyone has a different name. How about just calling it the computer like it really is??
Anyways, yeah, we're going to the dyno to make pulls with the wideband and get the a/f ratio where it should be w/ the s-afr. Other than that, why do you think we need an aftermarket ecu? I'd like to know the detailed reason of why an aftermarket ecu is better than getting the a/f ratio correct with a fuel controller... If it's just timing, we plan to get an Apexi timing controller once the new one hits the market.....


Thanks
Chuck

 

maybe it was a back fire

 

Oh I see... fuel cut off at 10.7 lbs of boost? That's just great... The fuel controller is going to do us no good if that's the case.
Alright, you convinced me. Will an aftermarket ECU fix all our driving problems we would encounter with this setup and make it perfectly safe to drive under all conditions?
Who has the best ecu for this setup?

Thanks
Chuck

 

I hope all it was, was a backfire. Sounded a lot stronger than a backfire though unfortunately. And it definetely effected the way the motor was running at the moment. Lost power and went down in rpm... If it was detonation, wouldn't it have blown the seal and started to run really really bad? If it was a turbo wouldn't it not be making boost anymore? It is still running perfectly fine, and the turbos are still making more than enough boost. So alas, I have no idea. Must be right... just a backfire. Unless the last guy who owned it put one heck of a strong motor in there......

Later
Chuck

 

i think porting the wastegate would be very benificial.
about the ecu, it mostly depends on what you plan on doing with the car. if you don't plan on adding a ton of more things, then an aftermarket like the pettit or m2 should do fine. but if you plan on adding a lot of things, something like the haltech or apex'i pfc is what you want...

BTW, where at in neb are ya?

 

If I've been running 11-15 lbs since yesterday... and I had the stock computer... wouldn't the motor be blown by now if it cuts off fuel at 10.7 lbs??? So how do I check to know if the ecu hasn't already been upgraded?


Thanks
Chuck

 

The stock ecu allows higher boost at lower rpm -- I believe 12-13 psi (look it up on Steve Ciriani's site). Also, it only cuts fuel for constant overboosting, not momentary overboosting.

Not to be to harsh but you seem to be taking a "head in the sand" approach to this. You already knew that running a full exhaust with the stock ecu was bad but I think you wanted us to tell you it was ok anyway..... ok, enough bashing on.

Get either the M2 or Pettit, they'll both be fine and safe to run 12 psi. If you want to do more upgrades later that require a PFC, you can sell your M2 or Pettit at little loss. Personally, I would just spend the money and get the PFC to start with, but that's me.

 

Well... I dont' know what you guys consider "going far" with these things. It's my brothers car, and we're both new to the whole rotary modifying thing... I think the plan is to keep the full exhaust, do a nice intake, good smic, etc etc.... I guess run low 12's with it?
I'm from Hastings, pretty good jaunt west of omaha... about 2.5 hours.

Later
Chuck

 

rynberg knows what he's talking about. if the car has to be driven around daily (or until you get an ecu), i would take the mp off and throw the cat on.

read this too:

 

Dude you are looking very amateur like with your posts

You didn't blow your motor it sounds like a backfire. You will know it when your motor goes. A full exhaust will make it sound crazy when you are accelerating and shifting hard.

I doubt the last owner upgraded the computer or he would have told you to try to convince you to buy it more.
If you want to check get where the passanger floor mat is and take off the panel on the right. That is where your ecu is.
You need to get a computer right away. I can't believe you haven't blown your motor already going to 15 psi or more on the stock computer. Find a used pettit and put it in right away. Also get a fuel pump to run 12 psi.

holy ****...

Snook

 

I have an intake and full exhaust. I ran the car on the stock ecu for a while. You will be fine as long as you can keep the boost down. I have the gt spec. cb. and I find it hard to control the boost. I am also non-seq. for that reason. I had to instal a home made boost controler. Put it this way, with my silencer out and boost controler wide open, it would boost up to like 17-19 "if I didnt let off the gas". With the silecer I can control it better, but now my boost pattern is 14 and then bleeds down to 9.
I did hit 13-14psi on the stock ecu and never did I hit fuel cut. Am I a lucky s.o.b (maybe). Even with the stock ecu I can spit 2 foot flames. I think people tend to go way overboard on this subject.
I do have one of the best aftermarket ecus for sale if ur interested.

 

It's not an opinion that we have about it being dangerous it's factual evidence.

Ask rynberg for info about where fuel cut is at every gear.

Zoom Zoom Zoom

or in your case

Zoom Zoom Boom

 

rynberg- Don't worry, you're not being harsh. I really don't mind. I may appear to be taking a "head in the sand approach", but it's really not like that at all. It's just the way the chain of events has gone with this car for us. It came with a downpipe on it when we bought it (which btw. We got it over the internet from a dealer in Dallas. All I know about the cars past is that he said it had many modifications that he removed and put on a different car. So I know it had been modified... just don't know how much so, and what all the dealer removed). In an attempt to try to figure out our boost problem we bought a very inexpensive midpipe off ebay to eliminate what we thought might have been a clogged cat. We figured we'd be alright for now since the car still retained the stock intake and cat back. Just recently my brother purchased a Racing Beat cat back off ebay for the car, and today he installed it as well as the HKS s-afr. For the last month the car has been at a shop getting all the vacuum lines replaced, checked for problems motor wise (non found, still made within 5 lbs of stock compression), boost problem diagnosed (was only making 5-6 lbs before). Found out to be a disconnected wastegate rod... Then installed a pair of manual boost controllers. So I figured with the boost controllers and HKS s-afr it would be alright for him to put on his exhaust, which he wanted to be on for his senior pictures which take place tomorrow.... So yes, I realize we haven't done things in the order of which they generally should take place... but it's what we have to deal with at this point. So, that's why I come to you guys. I don't have my head in the sand, I am simply ducking from the flames I knew were coming
Could you explain to me why you would recommend an Apexi PFC over an aftermarket ecu? And I'm curious... if all it controls is fuel, what makes it better than a s-afr? Just a lot more precise? How does it override the stock computers fuel cut off at 10.7 lbs? Just some thoughts... Trying to decide which route we want to go. With the mods I've listed, just tell me what you think. And what's a car with this kind of setup run through the quarter mile these days anyways?

Snook- Sorry for looking so amateur to you. Any particular reason why, besides asking a lot of supposed "ignorant" questions?
Yeah, backfire I'm sure. It's not the only time it's backfired with the new exhaust. I also tried to point it out that, I DO KNOW what it would be like if it was actually detonation.
Well, the 15 lbs is only an observation under part throttle. We certainly have not gone wot under these conditions. I assume if I'd go wot that the boost would not be spiking as much and would be lower. I'm just not ready to try because we have a brand new Spec stage 3 6 puck we're trying to break in......
You say get a fuel pump to support 12 psi? Is that adequate for what we are doing? I figure if we're going to be hitting 15 lbs every once in awhile I'd should have something capable of more than 12 lbs. Am I right?

Dan- Thanks for the encouraging words. Some think I'm looking for a reason to not upgrade. I am actually looking for a reason TO upgrade. Obviously I see now the stock ecu doesn't support over 10.7 lbs. That's what I needed to know... If it was just a/f ratio and timing tuning I figured we could handle that with a fuel and timing controller. So, I PM'd you for info on your ecu for sale.

Thanks
Chuck
Been working on cars since I was twelve. First car was a big block 68 Camaro RS/SS. Current car is a 97 Camaro SS that we're building a 383 LT1 with about 13:1 compression, solid roller and full roller shaft mount valvetrain, AFR 220 heads p&p'd by Race Prep in CA, and a whole bunch of other stuff... Hoping for 600+ horse n/a (Not gonna make quite the horses Jimlab is making... but he has more cubes ). The rest of the car is built to support the motor. One of my best friends has a "stage 11" 300ZX. 50k + invested. My dad has a 1950 Chevy 1/2 street rod we're in the process w/. Gonna have a complete art morrison chassis and a new 400 horse LS6 ZO6 motor. And of course a set of 20" rims for a little bling bling... I've been modifying cars since I was 13. I plan to attend SAM (samracing.com) starting next year. I am very familiar with performance oriented vehicles. I am NOT very familiar with FD3's. That is why I ask the questions.

www.barncandles.com/camaro/Chucks.htm

 

wow must be I have a special car(me being a smart ***), or the boost guage is wrong. When the oem ecu was in place, I hit 13 psi all the time and never did I hit fuel cut.
Before I went non-seq. I had some boost issues. it was like 7-9-11. So I drove all the way down to pettit from Michigan. It ended up being a bad precontrol. So after pettit was done with it, the boost pattern was 11-13-11. They told me that 13psi was on the very high end, but as long as it doesnt go any higher I should be fine. That was with the stock cat in place!
Whats the fastest anybody has gone in the 1/4 with the oem ecu? My best was 13.3 @ 112mph with a g-tech. so probly more like 108mph.
For all the people who thought I was going to blow a seal, kiss my ***. I have enough money setting aside for a big *** street port. I now have a RE ecu. Which im selling. Im gona go with some after market turbs., which Im looking to run up tp 19psi. I know that its not safe with just a aftermarket ecu, so thats why Im buying a pfc.

 

Agent:
I'm not calling you stupid.
I don't know that much but I do know that you can't run over 10 psi on the stock ecu. The entire time you were doing those runs you should have been bracing yourself for the motor to run lean and blow. This isn't like any other project car. You said you don't know much about rotary engines and mods. You need to read the forum A LOT and learn everything before you start putting on all these mods. A midpipe is a HUGE mod. To me that is as big a step as a single turbo.

On the stock ecu I would stick to just 10 psi tops!
If you get another ecu and want to run more then 10 I would get a fuel pump.
Then if you want to run over 14psi which I don't think helps the life of the stock turbos that much then you will need to upgrade your injectors to bigger ones.

stock ecu holds you to 10 psi
stock fuel pump holds you to 12 psi
stock injectors hold you to 14psi

Like everyone said, get a pfc if you are gonna keep modding the car. If not get a pettit and slap it on there so if you do hit in the mid to low teens in boost you are totally fine with the addition of a fuel pump.


Dan:
I dunno....haha

 

I would rearrange it like this:
stock ecu holds you to 10psi
stock IC holds you to 12psi
stock fuel delivery holds you to 14psi

 

Dan- With only a downpipe we managed a 13.5 at 108 w/ our car g-tech...... Really interested in your RE ECU btw... Just pm'd you.

Ya'll think his RE ECU would be adaquate? According to the details it should be perfect for our mods....

Snook- Give me some time, I've been reading as much as I can on this board. He's only had the car since May.
We'll take it easy with the stock ecu in there until we get an aftermarket ecu and fuel pump... I'll reschedule our dyno on monday. You think Dan's ecu would be a good choice? I think future mods only include an intercooler and intake.... Any guestimate with the full exhaust, intake, smic, and RE ecu would make hp wise and run in the 1/4 w/ around 13 lbs of boost?

Thanks
Chuck

 

Yo Chuck: I've got 2 pieces of advice for you:

1) Listen to what Rynberg said

2) Listen to what Rynberg said

He's an engineer and I am an Airframe and Powerplant mechanic.

We don't know **** about tractors, but I can guarantee that you are headed for
a large PING! (I suspect you already have) and then you will get to know
your engine on a REALLY intimate basis.

It only takes one time.........

Going 'round and 'round, your pal -

Ron

 

Yeah, we're going to get an aftermarket ecu and better fuel pump on the way before we do anything crazy.....

Thanks
Chuck

 

The stock fuel pump is just fine until you get over 350 hp or so. Put in a new OEM fuel filter before you do anything else.

Right on with the ecu, but just remember you are treading where only experienced tuners with wide bands fear to go.

Good luck!

BTW, my first Camaro was in 1972 - a 67 RS with a 327 if I remember correctly. Painted it metal flake gold - of course!

 

Ummm... what's that supposed to mean? Most don't do what we're doing?


Later
Chuck