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62mm pulley: misfire, fix, and new best 1/4 mile times

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Old 04-28-2013 | 01:28 PM
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Thumbs up 62mm pulley: misfire, fix, and new best 1/4 mile times

I finally installed my 62mm pulley and can report back to you guys:

I was afraid of running lean with the 62mm pulley and my other mods (exhaust, intake, cooling), so I didn’t install it until I had the accompanying fuel system mods in place. I installed a Walbro pump & regulator-less filter, new checkvalve, Aeromotive AFPR mounted under the hood, 6AN braided SS lines, Autometer FP gauge on the rail with Needswings’s fittings, and an Innovate Wideband O2. At Rob’s suggestion, I am using the 6AN lines as the new supply, and the factory hardline as the new return. A big “thank you” to Needswings, CV Products, Autometer, Russell, DJ Safety, RJS Racing, & Jegs, for the parts and discounts.

The fuel pressure with the factory regulator measured 58 psi. With the 62mm pulley I was seeing AFRs from 11.6 to 10.9 (not tuned). I have the AFPR at 56 psi and I am seeing AFRs from 12.2 to 11.6 Time will tell how much the ECU long term fuel trims will dial that back.

The first trip to the drag strip for spring “Test & Tune” was a disaster. I had horrible misfires. I could feel it, the car was setting check engine lights and misfire codes, and I bailing out of the throttle mid run. I checked the spark plugs and found that ten of the low-mileage NGK iridium plugs were gapped at .044, but on cylinder 3 one plug was at .046, and the other was at .050. The .050 plug had buildup on one side of the insulator and looked like it wasn’t always firing. Bakground: The two “pre-gapped” plugs on cylinder 3 were replaced previously when I was chasing down a bad ignition coil on that cylinder. So they were purchased separately from the other 10 plugs. I re-gapped all twelve plugs to .034 – .035 and went back to the track for the semi-annual “Import Faceoff” event.

Success! First run: 12.28 @ 112.5 mph! That was my best run. I was having a lot of traction problems through the first half of first gear and was not able to duplicate that time. I did trap as high as 113.50 mph on a 12.41 pass.

I went to the track a third time last night for the “Real Street Fights” event, but I just ran test & tune. I wanted to get my launches figured out. What I learned was that my traction problems previously were the track, not me. Last night I could launch however I wanted and the tires stuck it. My best run was a 12.42 @ 112.4. I ran 12.4s and 12.5s all night.
 
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Old 04-28-2013 | 01:38 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Additional info:

I WAS running ice in the ice tank. The ice tank does lower IATs, but uses a lot of ice. A 10 lb bag would melt before the run, albeit, leaving very cool water in the tank. Typical IATs for a run are: with ice: starting 77* F, 115* F at finish line, without ice: starting 93* F, 129* F at finish line. I did not see a consistent correlation between IATs and ET, which is interesting.

I have 255/50/16 Mickey Thompson ET Street Radials and MikeR rear camber arms at -0.5* rear camber. I may have more traction than you. 16 psi and a 1st and 2nd gear burnout worked best in the Mickeys. My 60' times ranged from 1.83 - 1.89, leaving the line at WOT, with little to no wheelspin.
 
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Old 04-28-2013 | 01:53 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

This car seems to run a “ringer” ¼ mile pass every so often and I do not know why. This is the start of my third season racing it.

1st season, basically stock, Johnson IC pump, baked potato IC mod, & separated cooling circuits:
Ran a best of 13.09 one night, but typically ran 13.2 to 13.5. Never ran a 13.1. 2.0 60’ times.

2nd season, 3” custom exhaust, 3” custom dual intake, Wavetrac rear end, MikeR rear camber arms, drag radials:
Ran 12.78 a couple of times, but typically ran 12.9 to 13.2. I did see some 12.8s on cool nights. 1.9 60’ times.

3rd season, now:
I have that one 12.28 timeslip, and a handful of 12.4 and 12.5 timeslips. 1.8 60’ times. It looks like she is a 12.4 to 12.5 car, that for some reason might run a 12.2 occasionally. I would love to know why the car does this – and make it stop.
 
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Old 04-28-2013 | 03:18 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

the gap is to much still. drop them down to 28 to 30 and try again. for gosh sakes get a tune on this car! its really senseless to run a high boost pulley with no tune

also theres no need to do a 2 gear burnout with the m/t. a 4 to 5 sec burnout ion first is all thats needed to heat them up and get the hook. any more is just wasting treadlife

were are you measuring fuel pressure at? if its at the schrader valve its a false reading. without a loop in the system your getting a high reading were the pressure builds first then it drops as it moves towards the firewall. i have seen a 6 psi drop from a oem fuel rail and a looped rail
 

Last edited by 32krazy!; 04-28-2013 at 03:43 PM.
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Old 04-28-2013 | 03:41 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

I ran a gap of .035 when I was stacked and the car screamed. I recently only decreased it to .033 due to running a 75 shot. Personally I'd leave the gap alone. The narrower the gap, the higher the ET from my experience.

Also, I recommend you launch it around 1,800 rpm's. If you can shave a tenth on the launch that can net you 2 tenths at the traps.
 

Last edited by grip grip; 04-28-2013 at 04:14 PM.
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Old 04-28-2013 | 05:08 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by boostmonkey
Additional info:

Typical IATs for a run are: with ice: starting 77* F, 115* F at finish line, without ice: starting 93* F, 129* F at finish line. I did not see a consistent correlation between IATs and ET, which is interesting.
so
ICE = dT of 38F end-start
NO ICE = dT of 36F
hmmm....

Can you safely assume that at 4gals/min and the volume you have - the IC after 12 secs is still seeing cycle1 water - me thinks so. That takes the HX out of it.....
Looks like the IC is the limitation here hey....
Also the fact that your let inwater temps would be nearer 35F and yet your IAT's are still 77-115 (dT 22-80) supports this.
 
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Old 04-29-2013 | 11:30 AM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by 32krazy!
the gap is to much still. drop them down to 28 to 30 and try again. for gosh sakes get a tune on this car! its really senseless to run a high boost pulley with no tune

also theres no need to do a 2 gear burnout with the m/t. a 4 to 5 sec burnout ion first is all thats needed to heat them up and get the hook. any more is just wasting treadlife

were are you measuring fuel pressure at? if its at the schrader valve its a false reading. without a loop in the system your getting a high reading were the pressure builds first then it drops as it moves towards the firewall. i have seen a 6 psi drop from a oem fuel rail and a looped rail
I knew you would give me a hard time about not being tuned Steve! That is the next mod on my list. I am leaning toward waiting until I can get her dyno tuned instead of getting a canned tune.

I would normally agree on the burnout, but the track was cold and I was waiting a long time between runs, so the tires were getting cold. Toward the end I got in a couple runs close together and I just scrubbed off the tires.

I am measuring fuel at the test port, and I do not have the looped rail yet, so the numbers may not be accurate as you say. The comparison between the factory FPR and AFPR is consistent at least though.
 
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Old 04-29-2013 | 11:47 AM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by Billy22Bob
so
ICE = dT of 38F end-start
NO ICE = dT of 36F
hmmm....

Can you safely assume that at 4gals/min and the volume you have - the IC after 12 secs is still seeing cycle1 water - me thinks so. That takes the HX out of it.....
Looks like the IC is the limitation here hey....
Also the fact that your let inwater temps would be nearer 35F and yet your IAT's are still 77-115 (dT 22-80) supports this.

I know, interesting right? The increase in IAT during the run is relatively consistent, independent of the starting temperature. There might be a variance of the starting or final temp a few degrees between runs.

I would not assume 4/gal/min. I have not tested the flow rate. I have a 2nd Johnson CM30 pump in the rear by the tank now. I believe the pump up front was cavitating trying to pull the water from the rear. Adding the 2nd pump increased the flow rate significantly.

I would ballpark a starting water temp or 50* F and ending of 80* F based upon feel for those runs with ice. So the dT across the IC is not quite as high as you think.
 
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Old 04-29-2013 | 11:53 AM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

I'm still trying figure out why you aren't quicker with that mod list.

When you say you used the factory fuel supply as a return line, are you saying you are looped back to the tank now?

I'm also really surprised at those low AFRs with the factory FPR and no tune! Guess I'd have to see some logs to see what it's doing.
 
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Old 04-29-2013 | 12:00 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by grip grip
Also, I recommend you launch it around 1,800 rpm's. If you can shave a tenth on the launch that can net you 2 tenths at the traps.
Stall RPMs affect a couple of things: 60' times, AND reaction times. I have definitely correlated that stalling at a higher RPM can lower your RT and 60' time, UNLESS you break traction. Spinning the tires, even just a little, on the launch can increase your RT, and lose you a race. Keep in mind I am competing, not just trying to set a best ET.

Also, it is VERY hard to accurately bump into the 2nd staging beam with the RPMs over 1100 on our low-stall converters. There isn't much time to bump in at a low RPM and stall up to a higher RPM before the lights drop. So being consistent there is hard.
 
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Old 05-06-2013 | 12:04 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by Buggin
I'm still trying figure out why you aren't quicker with that mod list.

When you say you used the factory fuel supply as a return line, are you saying you are looped back to the tank now?

I'm also really surprised at those low AFRs with the factory FPR and no tune! Guess I'd have to see some logs to see what it's doing.
She is as fast as she is. If you think something is slowing my car down I am all ears!

Yes, it is looped back to the tank, but not from the fuel rail, from the AFPR. The new 6AN line goes to the AFPR, The AFPR feeds the rail wth another new 6AN line, and then the return from the AFPR goes the the stock hardline which now connects to the tank return under the car.
 
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Old 05-06-2013 | 04:27 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

At the outset - I bet you feel an immense sense of satisfaction after all the preparation and finally going low 12's. The seat of pants dyno would be a wonderful feeling I'm sure.

Originally Posted by boostmonkey
...Walbro pump
...regulator-less filter
...new checkvalve
...Aeromotive AFPR mounted under the hood
...6AN braided SS lines
...Autometer FP gauge on the rail with Needswings’s fittings
...Innovate Wideband O2

At Rob’s suggestion, I am using the 6AN lines as the new supply, and the factory hardline as the new return. A big “thank you” to Needswings, CV Products, Autometer, Russell, DJ Safety, RJS Racing, & Jegs, for the parts and discounts.

The fuel pressure with the factory regulator measured 58 psi. With the 62mm pulley I was seeing AFRs from 11.6 to 10.9 (not tuned). I have the AFPR at 56 psi and I am seeing AFRs from 12.2 to 11.6 Time will tell how much the ECU long term fuel trims will dial that back.
.
Pics and/or a sketch if you have time.....

I'm particularly interested in the regulatorless filter (for later) - obviously not a WK720-1 - got a PN?
I'm due for a pump upgrade and want to change the filter at the same time. Of course regulatorless is obviously not where I want to be right now cause I'm not changing the regulated side just yet.

New check valve? - I understood the pierbergs have one already - Walbro no?
Purpose for the 2nd check valve is it for the return line?
 
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Old 05-07-2013 | 06:40 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by Billy22Bob
At the outset - I bet you feel an immense sense of satisfaction after all the preparation and finally going low 12's. The seat of pants dyno would be a wonderful feeling I'm sure.



Pics and/or a sketch if you have time.....

I'm particularly interested in the regulatorless filter (for later) - obviously not a WK720-1 - got a PN?
I'm due for a pump upgrade and want to change the filter at the same time. Of course regulatorless is obviously not where I want to be right now cause I'm not changing the regulated side just yet.

New check valve? - I understood the pierbergs have one already - Walbro no?
Purpose for the 2nd check valve is it for the return line?
This regulator. From Needswings.
Mann Mercedes High Flow Fuel Filter

Correct, the Walbro pump does not have a check valve. Rob sells one here. Though, I got mine from Jegs.
 
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Old 05-07-2013 | 07:00 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by boostmonkey
This regulator. From Needswings.
Mann Mercedes High Flow Fuel Filter

Correct, the Walbro pump does not have a check valve. Rob sells one here. Though, I got mine from Jegs.
tah
".... Purpose for the 2nd check valve is it for the return line? ....."
I'll do some more searching
 
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Old 05-07-2013 | 07:08 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Interesting... this is the first time I heard that I need a check valve to go with my Walbro. damn
 
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Old 05-07-2013 | 09:53 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by Buggin
Interesting... this is the first time I heard that I need a check valve to go with my Walbro. damn
I don't think you need a check valve unless you run the Needswings Adjustable Fuel Kit (remove the stock fuel filter/pressure reg).
 
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Old 05-08-2013 | 12:35 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

From Needswings.com:

This is a fuel safe in-line check valve to hold pressure in the lines/rail when the motor is turned off. With a week or non-existent factory check valve which is located on the outlet of the fuel pump the car will crank for an extended period of time before firing over. This is due to the fuel pressure bleeding back off to the tank when the car is off. This in-line check valve should be installed between the fuel pump and fuel pressure regulator to keep the fuel pressure from bleeding back through the fuel pump when turned off and still allowing a vent back to the tank through the regulator.

This check valve is recommended when using a Walbro fuel pump or if you're factory check valve has weakened over the years and you have excessive cranking time.
 
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Old 05-08-2013 | 01:22 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Well, I'll have to look further into that. I was away from my car for 30+ days. When I returned and went to pull my fuel rail/injectors, there was still lots of pressure there... so I think I'm ok.
 
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Old 05-08-2013 | 03:27 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

both of you guys need to carefully check your supercharger pullies. theres a thread on the e55 forum were more than a few e/c pullies have been failing. the spring straps are cracking and causing the failure.
i told a few on here and when they checked their e/c pullies again failures. look for cracks or brown dust around the straps and the gap from the clutch decreasing over time resulting in more shims needed. this is a sign of the straps weakening and failure will be immenent
 
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Old 05-08-2013 | 03:53 PM
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Default Re: 62mm pulley: misfire, fix, and new best 1/4 mile times

Originally Posted by 32krazy!
both of you guys need to carefully check your supercharger pullies. theres a thread on the e55 forum were more than a few e/c pullies have been failing. the spring straps are cracking and causing the failure.
i told a few on here and when they checked their e/c pullies again failures. look for cracks or brown dust around the straps and the gap from the clutch decreasing over time resulting in more shims needed. this is a sign of the straps weakening and failure will be immenent
Linking this, only as an FYI and not an accusation.

EC Supercharger pulley failure... - MBWorld.org Forums

Mine is post #87

MBWorld.org Forums - View Single Post - EC Supercharger pulley failure...

From the sound of things, Eurocharged is standing behind the product and supporting those with failures. Kudos to them for that. I consider them to be friends, and good folks to work with.
 



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