Ran a new PB with issues and would like some advice (a bit of a read)
05-16-2007, 07:02 PM
#1
Ran a new PB with issues and would like some advice (a bit of a read) This past Monday I ran my car at a rental.
Wasn't sure what she'd do with the changes I've made. Also wondering if I cured the rich condition off the line.I was hoping for at least high 13x mph and low 10's.
Previous set-up:
9.1 comp 346, D1SC, Ported heads, TR 224/227, 60 lb/hr Moto's, SDCE tensioner, FMIC
dual 3" inlet hat, TTS Longtubes, 3"y - 4" over axle - 3" dual exhaust, M6, 12bolt w/3.73's.
18 deg timing, 13-14 psi @ 6200, 93 octane
672 rwhp/600 rwtq SAE
Dynoed on stock 10 spokes with MT DR's @ 25psi
Changes:
weight removal (-212lbs), tire screws, 3.5 pulley to a 3.3, meth/alky injection, 75 lb/hr injectors, descreened MAF, and ported TB).
To my surprise she ran a 10.38 @ 142mph w/1.74 60' right off the trailer.
When I got the slip I couldn't believe it.
Next pass was the best one of the day. I brought in a little more meth because the last pass leaned out a little up top and ran a 10.29 @ 143mph w/1.71 60' @ 11:40am
. (last PB was10.71@135.2)
The next couple passes dropped to 137mph. I was scratching my head at that then remembered about the "IAT vs Temp" retard in the PCM. It was later in the day and inlet temps were rising and it was pulling a few degrees of timing killing power.
The actual inlet temp was much cooler though than what the sensor was reading due to the alcohol. However, the sensor doesn't get a chance to read the temp change when the alcohol is spraying. Even though the nozzle is slightly in front of the IAT sensor, the column of air in the pipe is so great the mist never reaches the other side of the piping where the sensor is.
I may need to move it's location to the other side of the piping in-line with the IAT.
To get around this issue at the track, I tuned out the "timing pull" in that table so full timing would come back regardless. It worked and next pass out it ran 141.59mph
.
It stayed at that mph for my next 4 passes. This was later in the day which was warmer and I was also dropping psi in the tires looking for traction.
Found out my tire gauge was reading 2psi more than what it was on a real guage
. Also learned I need to do a monster burnout on the Hoosiers to get them to hook.
10psi and 2nd gear burning them until they started dragging the motor down was the winning combo.
5k-6250 rpm and it would hook. Unfortunately the rich condition was still there due to the referenced FPR . I was hoping removing the vacuum signal from it would fix the situation from last time.
It did to a point and added another 1k useable launch rpm but once she hooked and psi spiked, the regulator spiked fuel pressure and bogged the motor down. The motor also had to overcome a surge of alcohol since the signal from that is also map referenced.
I know what I have to do to fix it. Need to revise my fuel system. I need more pump and I want to ditch the ref'd FPR to eliminate the pressure spike on the line.
Right now I have a "Nasty" sumped tank, SX-18203 pump (Ultra high-flow rates exceed: 80 GPH at 12 volts and 45 PSI, AND 120 GPH at 12 volts and 10 PSI), -8 feed into 1 rail-crossover-then out to reg, Billet rails, RC 75lb injectors, SX ref'd regulator @ 60psi, Stock feed as return.
Fp starts taking a nose dive around 4800 even referenced. Because of this my
PE table looks like a Supra dyno graph.
Now for the advice.
Would it be better to find a higher volumn single pump or is there an easy/reliable way to piggyback/y-in another pump?
Will the stock feed line be a sufficient return-line or will it be to small to handle the extra volumn?
Should I run a dedicated -6 for it?
The car sees the street alot so a single large pump will circulate alot of fuel. I have a new uninstalled aeromotive pump controller to help out but some larger pumps specify a reduced life using this. I'd prefer to work it out so I don't need it just to keep things as simple as possible.
I also plan on changing to a y-block to feed both rails and then a y-block out the front to the regulator.
I know what I need to do, just undecided on the best way to go about it. Any advice is appreciated.
Once I get that ironed out, she should really fly.
I don't have any pics really because I was messing with the car all day but here's a couple on the trailer and one of my slip. Also vid of my 1rst, 2nd, and last pass of the day.
Wasn't sure what she'd do with the changes I've made. Also wondering if I cured the rich condition off the line.I was hoping for at least high 13x mph and low 10's.
Previous set-up:
9.1 comp 346, D1SC, Ported heads, TR 224/227, 60 lb/hr Moto's, SDCE tensioner, FMIC
dual 3" inlet hat, TTS Longtubes, 3"y - 4" over axle - 3" dual exhaust, M6, 12bolt w/3.73's.
18 deg timing, 13-14 psi @ 6200, 93 octane
672 rwhp/600 rwtq SAE
Dynoed on stock 10 spokes with MT DR's @ 25psi
Changes:
weight removal (-212lbs), tire screws, 3.5 pulley to a 3.3, meth/alky injection, 75 lb/hr injectors, descreened MAF, and ported TB).
To my surprise she ran a 10.38 @ 142mph w/1.74 60' right off the trailer.
When I got the slip I couldn't believe it.
Next pass was the best one of the day. I brought in a little more meth because the last pass leaned out a little up top and ran a 10.29 @ 143mph w/1.71 60' @ 11:40am
. (last PB was10.71@135.2)The next couple passes dropped to 137mph. I was scratching my head at that then remembered about the "IAT vs Temp" retard in the PCM. It was later in the day and inlet temps were rising and it was pulling a few degrees of timing killing power.
The actual inlet temp was much cooler though than what the sensor was reading due to the alcohol. However, the sensor doesn't get a chance to read the temp change when the alcohol is spraying. Even though the nozzle is slightly in front of the IAT sensor, the column of air in the pipe is so great the mist never reaches the other side of the piping where the sensor is.
I may need to move it's location to the other side of the piping in-line with the IAT.
To get around this issue at the track, I tuned out the "timing pull" in that table so full timing would come back regardless. It worked and next pass out it ran 141.59mph
.It stayed at that mph for my next 4 passes. This was later in the day which was warmer and I was also dropping psi in the tires looking for traction.
Found out my tire gauge was reading 2psi more than what it was on a real guage
. Also learned I need to do a monster burnout on the Hoosiers to get them to hook.10psi and 2nd gear burning them until they started dragging the motor down was the winning combo.
5k-6250 rpm and it would hook. Unfortunately the rich condition was still there due to the referenced FPR . I was hoping removing the vacuum signal from it would fix the situation from last time.
It did to a point and added another 1k useable launch rpm but once she hooked and psi spiked, the regulator spiked fuel pressure and bogged the motor down. The motor also had to overcome a surge of alcohol since the signal from that is also map referenced.
I know what I have to do to fix it. Need to revise my fuel system. I need more pump and I want to ditch the ref'd FPR to eliminate the pressure spike on the line.
Right now I have a "Nasty" sumped tank, SX-18203 pump (Ultra high-flow rates exceed: 80 GPH at 12 volts and 45 PSI, AND 120 GPH at 12 volts and 10 PSI), -8 feed into 1 rail-crossover-then out to reg, Billet rails, RC 75lb injectors, SX ref'd regulator @ 60psi, Stock feed as return.
Fp starts taking a nose dive around 4800 even referenced. Because of this my
PE table looks like a Supra dyno graph.
Now for the advice.
Would it be better to find a higher volumn single pump or is there an easy/reliable way to piggyback/y-in another pump?
Will the stock feed line be a sufficient return-line or will it be to small to handle the extra volumn?
Should I run a dedicated -6 for it?
The car sees the street alot so a single large pump will circulate alot of fuel. I have a new uninstalled aeromotive pump controller to help out but some larger pumps specify a reduced life using this. I'd prefer to work it out so I don't need it just to keep things as simple as possible.
I also plan on changing to a y-block to feed both rails and then a y-block out the front to the regulator.
I know what I need to do, just undecided on the best way to go about it. Any advice is appreciated.
Once I get that ironed out, she should really fly.
I don't have any pics really because I was messing with the car all day but here's a couple on the trailer and one of my slip. Also vid of my 1rst, 2nd, and last pass of the day.
Last edited by SSmokin 01; 05-16-2007 at 08:04 PM.
05-16-2007, 07:59 PM
#4
Dont know what to tell you for the fuel setup. its rough finding something that can keep up with a lot of power and not get hot street driving. I have had no issues at all with the big magnafuel pump but stealth it isnt..
I still have my rails with a crossover and have no issues at all, I dont try to boost reference any more either. I just run 62psi static but I have 83lb injectors, with 60s you are getting on the edge with that power and 62psi.
Your 60 foot is horrible though, you could maybe use more gear and you can probably use more timing down low. Dont be afraid to run 25 degrees or so where the boost is low and ramp it down as the RPM goes up. Either way you have it pretty figured out, just need to get the launch down - congrats on the numbers.
I still have my rails with a crossover and have no issues at all, I dont try to boost reference any more either. I just run 62psi static but I have 83lb injectors, with 60s you are getting on the edge with that power and 62psi.
Your 60 foot is horrible though, you could maybe use more gear and you can probably use more timing down low. Dont be afraid to run 25 degrees or so where the boost is low and ramp it down as the RPM goes up. Either way you have it pretty figured out, just need to get the launch down - congrats on the numbers.
05-16-2007, 09:07 PM
#5
Thanks for the compliments.
I have 75lb injectors now. I'll try some more timing down low along with the impending fueling revisions. Thanks for the advice.
Originally Posted by kp
Dont know what to tell you for the fuel setup. its rough finding something that can keep up with a lot of power and not get hot street driving. I have had no issues at all with the big magnafuel pump but stealth it isnt..
I still have my rails with a crossover and have no issues at all, I dont try to boost reference any more either. I just run 62psi static but I have 83lb injectors, with 60s you are getting on the edge with that power and 62psi.
Your 60 foot is horrible though, you could maybe use more gear and you can probably use more timing down low. Dont be afraid to run 25 degrees or so where the boost is low and ramp it down as the RPM goes up. Either way you have it pretty figured out, just need to get the launch down - congrats on the numbers.
I still have my rails with a crossover and have no issues at all, I dont try to boost reference any more either. I just run 62psi static but I have 83lb injectors, with 60s you are getting on the edge with that power and 62psi.
Your 60 foot is horrible though, you could maybe use more gear and you can probably use more timing down low. Dont be afraid to run 25 degrees or so where the boost is low and ramp it down as the RPM goes up. Either way you have it pretty figured out, just need to get the launch down - congrats on the numbers.
Trending Topics
05-18-2007, 08:29 AM
#11
Two step wont make it any faster really, when you drop the clutch and floor it you have whatever boost it will make at that rpm, its not a turbo.
What it will help though is make it a lot easier on the starting line not having to try to hold it at a certain rpm with your right foot. Getting a M6 car to 60 foot well whether its NA or supercharged is a bit of a challenge. Just takes a lot of experimenting and a solid driveline.
What it will help though is make it a lot easier on the starting line not having to try to hold it at a certain rpm with your right foot. Getting a M6 car to 60 foot well whether its NA or supercharged is a bit of a challenge. Just takes a lot of experimenting and a solid driveline.