Cylinder's #9 and #10

[EllowViper]

I was doing some more diagnostics regarding the issue with my recent #5 lbs ROE install and the popping/missing going from vacuum to mild/heavy boost and the significant backfiring on decell. Currently have the basic ROE 6C and 9C smart card programs. I know there is a chronic issue with ROE motors regarding tuning cylinder’s 9/10 and the issue of poor low RPM running due to the “short” intake runner design under vacuum. So there is a variety of issue to work through with tuning this engine. I know owners have posted that their ROE cars run better than “stock”, but I’m not there with the basic ROE tune provided. No luck on the forum search so here we go again. Sean wanted me to check for potential vacuum leaks so I pulled mine down last night. Everything looked OK from a mechanical install perspective. Bypass valve holds vacuum just fine. I did put my 02 sensor extensions on and moved both sides to the collector vice the single tubes on each side (Bellanger Headers). Checked all plugs/wires. Plugs #9 and #10 were BLACK and SOOTY. All the others were fine, if not running a bit too cool IMO (but I haven't done much WOT running since it runs so poorly and I don’t want to push my creampuff too hard with the current tuning issue). When I did a run today with the 02’s in their new position in the collectors (95 degrees and high humidity), the car now pings really bad under mild acceleration (didn’t before with the 9C card and the 02 sensors in the single header tube) and I’m fearful to really get into WOT since I have to get through closed loop first…and I don’t’ think my tune will get me there. So, now that cylinders 9 and 10 are feeding the overall 02 readings on each bank in closed loop, me thinks the ECU is compensating by leaning out all injectors to the point that now I’m pinging under mild closed loop acceleration. I really need an A/F sensor in each header tube!! Still not throwing any codes, but it looks like the time has come to get the ROE tuning software, A/F sensor, and start data logging. It was a simpler life as a N/A stocker. Anyone running a better tune on a basic ROE 5 lbs set-up than the ones Sean provide?? If so, what were the basic changes from the ROE cards since they seem to think they should be pretty close to achieving good drivability out of the box? I've looked at Damn Yankee's tuning videos... so addressing each cylinder's specific tuning criteria is achievable with the VEC, just curious if anyone's been down this road before.

 

[KenH]

You're not alone. Many people including myself have had problems with getting the Roe tuned. In my case the car would barely run at all with Sean's standard cards.

When I moved my O2's to the collector location, my car ran very lean during closed loop operation. Once I moved them back up to the header tube, it ran fine again.

It should be safe to lean out your #9 & #10 cylinders a little at a time and go by your plug readings.

I highly recommend investing in a WBO setup in the car as you mentioned or else you are running blind.

In my case, the biggest change that I had to make was to increase the injector offset all the way up to 74%. Sean and I found this by literally backing all tuning out and starting from scratch which was to log the fuel adaptives and set the injector offset. We never understood why my car was so much different than most other cars.

 

[EllowViper]

Thanks KenH. I've followed your past posts over the years and appreciate your expertise. I agree with your appraisal and logical approach. I'm currently getting a basic used POS laptop with Windows XP so I can run Sean's tuning software. I'd get a new laptop but they all are running Vista and the last word I got is that the ROE software won't run on Vista. I'll be getting an Innovate Wideband too. For what the local tuners want to do a dyno tune, I can buy all this myself and with some assistance from the Forum, have some fun figuring it all out!!!

 

[plumcrazy]

wasnt there some sort of fix for that problem a while back ?

 

[dave6666]

The next generation of SC from Roe is going to fix that problem. Well, if you want to spend $7,500.00 AGAIN!

 

[KenH]

Tuning can be fun and Sean is very helpful in getting the bugs worked out as are those of us that have been down the same path.

The biggest tuning challenge is the change in A/F with temperature. If you are pinging when it is hot out, you will really be running lean when the temperature goes down. I keep waiting for the VEC3 guys to get off their duff and figure this AIT stuff out and if they do, I'll upgrade my VEC2. Water/methanol is also a tuning challenge, but I'm guessing you aren't running that. Another tricky tuning spot is where the car transitions from vacuum to boost. You do want to be careful with the tune, because with cast pistons, even a 5lb pulley setup can take them out if the tune is off.

I have always had a fair amount of popping even when the car is running good. Different plugs can have an affect on that. I have tried quite a few and currently run the NGK Iridium plugs and are fairly happy with them.

The firmware upgrade released a year or so ago helped the cylinder #10 problem, but you still need to pull some of the fuel out manually. If you have an older VEC2 that you bought used, you should update the firmware to the latest.

I keep hearing rumblings about a new Roe SC, but no facts. Anyone have any facts?

--- Ken

 

[Joseph Dell]

The even larger problem with both the roe and turbos (more the ROE b/c it hits full boost by 2k RPM) is the 'tip-in'. tip-in is the transition from vacuum to boost. since the stock PCM doesn't have to deal with a 'rate of acceleration' parameter beyond standard naturally aspirated WOT, AND since the VEC2 doesn't have a parameter of this sort either, there isn't an easy way to get the tip-in to be flawless from 2k no-boost to WOT. Easing into throttle isn't a problem, but mashing the go-fast pedal makes things somewhat challenging.

An AEM can be tuned to eliminate this tip-in issue b/c the AEM has an acceleration rate parameter (actually, 6 for accel and 6 for decel) but that doesn't help y'all here.

remember that the VEC is a (albeit very good) piggy-back computer. so you are still having to deal with many of the stock PCM issues such as not being able to handle a roots/twinscrew blower very well.

my .02... there is more to it than that, but this is a good start for the discussion...

JD

 

[EllowViper]

Thanks guys. I did upgrade my VEC-II with the new VEC-III firmware.

 

[Schulmann]

First install a WBO on both sides of the engin after the headers. It will help you to get a good idea when the AFR gets really rich. It is very important to know exactly your AFR. Without this information you are just bild guessing your issue.


With the AFR and the Vacuum reading from the VEC2 you can fix your issue in less than 2 minutes.

It is very easy to tune the VEC2 and the Roe supercharger once you have the AFR reading.
Without AFR you are just heading for more and more troubles.

My fuel offsets were high for hwy driving at cylinder #9( 0.6ms) and #10 (1.2ms).

I even had a program for extended hwy driving yielding 31mi/g consumption .... I was running 16AFR I was able to drive nearly 100mi more than the other guys in the club.

 

[99 R/T 10]

How safe is it to run at 16 A/F? Even if you're carefull not to get on the throttle, is't that running on the edge? I get 17 MPG on the highway, that would just about double what I'm getting now.

 

[EllowViper]

I guess my initial strategy would be to run the Wide Band in the single tube first to get a baseline A/F ratio. I have the stock 02 sensors in the 2-into-one ****. That would be on eiither # 3 or #4 cylinders since they have the single cylinder 02 ****...and then put the wideband into the collector to get an A/F ration that includes either # 9 or # 10. I have many 02 bungs...single cylinder, two into one, and all five in the collector...one each side. Since #1-8 all appear to be the same when looking at the plugs, I think the A/F on those are pretty close. What I need to isolate are the A/F ratios on #9 and #10. They are REALLY rich from how the plugs look. If per se the A/F on #4 is 12.0 and then I put the wideband into the passenger collector and take a combined reading of cylinders 2,4,6,8,10 and its 11.5, I could infer that #10 is really messed up and manipulate the fuel management scheme until I theoretically achieved the desired 12.0 across all five cylinders. Again, that's assuming 1-8 have a basically balanced A/F ratio. Just thinking here. If anyone esle has a way to isolate the A/F in #9 and 10 short of instlaling a separate 02 **** into those tubes, chime in.

 

[Steve 00RT/10]

My car is a 5 pounder...no water / ****.

I think the factory O2s should be in the collector area as they came from the factory. If not, you are only sensing one tube for closed loop operation. Others could be too lean.....you would never know.

My WB is in the horizontal turn out area.

Shortly (750 miles) after my initial install, I set a lean code. I then checked LTFT It was +28% on one side. I had to move the factory Roe set from 65 to 70% to get my LTFT to roughly +/- 5%.(it can never be perfect so no sense chasing it too far). I also removed fuel from all cylinders after bumping the base set up---especially 9 & 10. I pulled the plugs a few times to check their condition.

I have been using the IAT feature on my upgraded VEC 2s. I am set at +15.5 / -12.5%. Seems to work well enough for hot temps..........still have try it out cold. My temp parameters are set at 35F to 126F.
Higher than 126 and I will not remove any more fuel so as to have the slight cooling effect when hot. The line crosses about 83F to add / subtract.

Transition from vacuum to boost has been an issue, but with Roe stock spark curves, maybe not as much as someone running on the edge.

My car pops quite a bit as well. I'm running the Bosch plugs that came with the kit

As KenH says.....running without a WB is running blind.

The Roe software will run on Vista

My initial Sean Roe card was very rich!

Steve

 

[EllowViper]

Hey, Thanks Steve. I was going to call Sean today to see if the tuning software will now run on VISTA. I guess you have answered that!! I have a new company laptop in the mail so that is great news. I drove the car into work today and threw a CEL...so I'll have to check that out this evening. First time I've ever thrown a CEL since the install. I'll order the tuning software today, order an Innovate WB, and get set for some initial tuning sessions. I'm really curiuos as to the baseline tune (non-tune) that's on it. Thanks to all again!!

 

[Steve 00RT/10]

The VEC software will run on Vista, but if you buy the EASE diagnostic software from Sean.....for LTFT adjustment----make sure it's the upgraded one. My EASE from Sean last year would not run on my new Vista Dell this spring...........I disliked Vista enough that I changed the computer back to XP and couldn't be happier. EASE does now make a compatible product. Any garage with a diagnostic tool can check your LTFT for you in a matter of minutes. Might be the cheaper way to go to get a snapshot of where you're at.

Good luck

Steve

 

[Purdue_Boiler_Viper]

The even larger problem with both the roe and turbos (more the ROE b/c it hits full boost by 2k RPM) is the 'tip-in'. tip-in is the transition from vacuum to boost. since the stock PCM doesn't have to deal with a 'rate of acceleration' parameter beyond standard naturally aspirated WOT, AND since the VEC2 doesn't have a parameter of this sort either, there isn't an easy way to get the tip-in to be flawless from 2k no-boost to WOT. Easing into throttle isn't a problem, but mashing the go-fast pedal makes things somewhat challenging.

An AEM can be tuned to eliminate this tip-in issue b/c the AEM has an acceleration rate parameter (actually, 6 for accel and 6 for decel) but that doesn't help y'all here.

remember that the VEC is a (albeit very good) piggy-back computer. so you are still having to deal with many of the stock PCM issues such as not being able to handle a roots/twinscrew blower very well.

my .02... there is more to it than that, but this is a good start for the discussion...

JD

Anyone know if the Roe PCM handles these issues better?

 

[EllowViper]

As I stated, drove the car into work today and threw a CEL... Well on the way home, I was messing with the transition from closed-loop to WOT in a continuing effort to listen, learn, and analyse things under load/speed/varying condition. I got a ticket by a motorcycle cop I simply didn't see in all my playing around. 100 in a 65...it figures. He wondered why I blew by him and how I couldn't have seen him. I told him I was concentrating on other things at the time. Off the the Judge next month for my medicine.

 

[Viperless]

Well that *****!

 

[Steve 00RT/10]

Anyone know if the Roe PCM handles these issues better?

As far as I know, the Roe PCM is only an earlier GEN II forged piston PCM. I have one in my car. Cast piston cars have always had MIL problems with exhaust mods. Throw in a lightweight flywheel, 3:45 gears, and SC and you can possibly get into misfire codes as well. The 96 PCM take care of these problems. I still get a random PO153 code, but that's about it for MILs.

Steve

 

[EllowViper]

The CEL I got was for the left and right 02 sensor heater fault. Kinda weird. All I did was move the sensors from one **** to the 2-into-1 further downstream.

 

[KenH]

It takes longer for the O2 sensor to heat up when it is down in the collector than when it is in the header tube, hence more likely to throw a O2 heater code. While I understand the desire to measure at the collector, I don't think it really makes that much of a difference in practice.

 

[ViperTony]

It takes longer for the O2 sensor to heat up when it is down in the collector than when it is in the header tube, hence more likely to throw a O2 heater code. While I understand the desire to measure at the collector, I don't think it really makes that much of a difference in practice.

For me it did. I was running really rich ( low 10's ) during WOT after the Belanger headers, cats and catback were installed. Prior to the Belanger system, I had a similiar B&B exhaust setup & Borla Headers (O2 in the collector area) and my AFR was perfect, no tune. That changed as soon as I switched to Belanger. Wizard suggested I move the O2 sensor to collector area. He said this is recommended for S.C. applications with Belangers but not really needed for my n.a. but it wouldn't hurt. All plugs looked fine and there were no signs that any particular cylinder was running richer than the other.

Sure enough, after moving the O2 sensor from the single primary tube to the collector my Viper ran less rich. Not perfect but much, much better as my AFR moved back up into the 12's during WOT. AFR during closed loop also runs more consistently between 14.4 and 15.1 now. I immediately threw a code after moving the O2 but it has never popped up again.