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No leaks that I can find. I'm starting to think the regulator needs to be after the injectors and feed the other end. My plugs are really really clean. Way to clean for me.
What is safe timing off the brake? I have it set to be locked at 35deg until 8psi. Then it goes back to the main map. It's at 20 degrees in my log @ 4500rpms right off the hit and ramps down to 15 by 6000rpms.
Have you done a boost leak check? Positive the hotside isn't leaking?
What the car is doing makes sense to me. You had a nice low rpm setup. Now you slapped on a long runner intake and bigger turbo. You aren't making enough power down low and the RPM is hanging after the launch. All very typical of too much gear or not enough converter. Either adjust the gear/tire, converter, or the power level. Boost **** is the easiest adjustment IMO. Higher Rpm will couple the converter better as well. Rev that sucker to 6500-6800 at 18-20lbs of boost see what happens.
Your timing on the brake sounds fine to me as long as it jmps back to map timing once the brake is released and the engine is under heavy load. Usually you want the timing at peak torque to be lowest. Then you can ramp it back up slowly with RPM.
Having the return on the regulator and deadheading the rails should be fine. I do that as well as a ton of other people. Unless your rails are an odd design? I use the factory Fbody rails. Sounds like your pump isn't up to the job or it's having issues. Fuel filter maybe who knows... But I'd fix that first. What pump are you running?
I will double check there are no leakes. All vbands are tight ect. I'm using a mallory 110fi pump -8 feed. Good for continuous 65psi makes up to 100 psi so they say. I can accept having to crank it up more, that's the plan anyway. I want to run 18-20 and rev it up just like you say. I kinda wanted to work up to it. I have spare short blocks so what the heck why not hit it hard. I will sort the fuel pressure issue out and then get my methanol injection installed so I can run more boost.
No leaks that I can find. I'm starting to think the regulator needs to be after the injectors and feed the other end. My plugs are really really clean. Way to clean for me.
Are you saying your fuel pressure regulator is pre-fuel injectors? If so, the only regulating its doing is the incoming feed, it needs to be after the injectors to regulate the fuel pressure taking into account the drop from the injector consumption. I've seen other guys blow motors because they didnt have their fuel pressure regulator setup right.
While I do agree it’s a better design to put it after the rails…it is not required and will not “blow your motor”.
The fastest stock block record holder set his car up just as the OP has AND is running E85 on the factory rails just like me around 100psi of fuel pressure. Running these things into the 900hp range easy on e85 without issue on the factory rails with the return mounted on the regulator. Im only running around 70psi of pressure total.
At his power levels on pump gas, the OP should be more than "ok".
While I do agree it’s a better design to put it after the rails…it is not required and will not “blow your motor”. The fastest stock block record holder set his car up just as the OP has AND is running E85 on the factory rails just like me around 100psi of fuel pressure. Running these things into the 900hp range easy on e85 without issue on the factory rails with the return mounted on the regulator. Im only running around 70psi of pressure total. At his power levels on pump gas, the OP should be more than "ok".
Agreed, I ran mine in this fashion for quite some time with no issues. Although on my new setup I ran the regular post for good Measure (in case the regulator failed for some reason)
Seems to me that you need more gear in the rear end then 3.50. Something like a 4.11 or high would work well. What first gear in the 4l80? What are your plans for the car, straight drag or cruiser? I would start with a set of new gears and then move to getting a better converter. Your 60' isn't all that great at all. Take small moves don't change everything at once or you will be chasing your *** for a long period of time. Make small changes and see if they benefit.
While I do agree it’s a better design to put it after the rails…it is not required and will not “blow your motor”.
The fastest stock block record holder set his car up just as the OP has AND is running E85 on the factory rails just like me around 100psi of fuel pressure. Running these things into the 900hp range easy on e85 without issue on the factory rails with the return mounted on the regulator. Im only running around 70psi of pressure total.
At his power levels on pump gas, the OP should be more than "ok".
How does a FPR put before the injectors compensate when the pressure drops post FPR? A FPR after the injectors allows a given amount of fuel to pass by to the return in order to keep a fixed fuel pressure. If its before the injectors and you drop pressure due to power level, how does the FPR compensate? And I can link to threads in this section where people HAVE blown their motor up because of this setup. A sponsor on here set it up that way too.
How does a FPR put before the injectors compensate when the pressure drops post FPR? A FPR after the injectors allows a given amount of fuel to pass by to the return in order to keep a fixed fuel pressure. If its before the injectors and you drop pressure due to power level, how does the FPR compensate? And I can link to threads in this section where people HAVE blown their motor up because of this setup. A sponsor on here set it up that way too.
No. What you see are people who don't know any better blaming their blown motor on a FPR install. Otherwise it wouldn't work just fine for some and not for others. I run 25lbs of boost through my motor with a "deadheaded" fuel rail. I've never had an issue with fuel pressure.
What would cause the pressure to drop post regulator? The regulator top chamber is seeing your desired regulated pressure. This top chamber is shared with the fuel rail in a basically closed system. Nothing will cause an excessive (motor blowing) drop in pressure post regulator unless the pump can't keep up with the injector demand or the rail flow itself is maxed out. If that's the case installing a regulator post rail isn't going to fix the problem either.
Like I said... post is a better design, but not necessary or dangerous at moderate power levels.
My regulator is set up like the pic above. I'm going to try some things tonight like moving the feed line to the rail first. Lower the fuel pressure to see if it falls off less.
What the car is doing makes sense to me. You had a nice low rpm setup. Now you slapped on a long runner intake and bigger turbo. You aren't making enough power down low and the RPM is hanging after the launch. All very typical of too much gear or not enough converter. Either adjust the gear/tire, converter, or the power level. Boost **** is the easiest adjustment IMO. Higher Rpm will couple the converter better as well. Rev that sucker to 6500-6800 at 18-20lbs of boost see what happens.
I agree with Forcefed. The car just needs more pressure and power to move the car out of the hole with the new bigger setup. Everything else seems kosher.
Something is off. You're leaving at 4300rpm with 11.5lbs of boost. 3/4 of a second later your at the same rpm and 12lbs. You were on the limiter for close to half a second at the top of first. I don't see anything in your log that would keep the car back when you let go of the brake. It looks like it unloaded the tires a couple of times I'm wondering if that had something to do with it. Get it to leave hard, stay off the limiter and increase your shift points and your times will come down big time. Fix the fuel pressure issue and keep an eye on your voltage. It drops from 14.2 to 12.8 when you shift gears. When you switched transmissions and driveshafts you made sure you had enough play for the trans yoke?
Curious about the fuel pressure...mine dips at gear changes also (as boost momentarily dips) but my fuel pressure mirrors my map sensor data as it should - its a boost-referenced regulator.
Trans yoke has 1 inch of play just like strange says it should. The car revs so fast over 5500 I had trouble shifting it fast enough. I can't get why it takes one second to start making rpm. The converter is loose as hell. I am working on the fuel pressure issue tonight. I will log some stuff later if it works out.
Switched the fuel lines up. single -8 feed wye into 2 -8's into the back of the rails. 2 -8's out of the front of the rails to the regulator. It seemed to run more smooth this way and its a tad rich now but the cl comp was keeping it where it needed to be for the most part. It still looses fuel pressure with rpm. I guess I'm out of pump. I bet the way I had it would have worked if I had a better pump. I will try running lower base pressure and see if it gets better. I use to run 43 psi base and didnt have this problem. I have it up higher because I wanted to try it and see if it ran any better. I got my answer on that, cant run 58 base with the pump i have. Got lots of logs too, I will send one over. Thanks for the help guys. Its nice to have outside input.
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