What fuel pump for 120lb injectors?

Should I try locking the converter 1/2 way down the track to see if the converter is slipping excessively? Converters are one thing I don't know a whole lot about.

If I am running 20lbs of boost at 11:1 AFR, and up it to 24lbs, I know my fuel pressure also will go up by 4lbs. Would I most likely run lean if I didn't add more fuel to the chip? I haven't done alot of testing on this, but it seems like I do need to add a few % of fuel when I go up in boost.
 
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89mulletbird said:
Should I try locking the converter 1/2 way down the track to see if the converter is slipping excessively? Converters are one thing I don't know a whole lot about.

If I am running 20lbs of boost at 11:1 AFR, and up it to 24lbs, I know my fuel pressure also will go up by 4lbs. Would I most likely run lean if I didn't add more fuel to the chip? I haven't done alot of testing on this, but it seems like I do need to add a few % of fuel when I go up in boost.
Click to expand...

Convertor .. what type is it multidisc clutch ?

my TTA race weight is no where near 3800 pounds im about 200 .. car must have some subs in it ??

Your fueling ... it depends ... you may or may not have to touch the chip .. just raising boost does NOT mean you will have to add fuel in the chip.. the FPR should provide the added fuel... that is taking into account your fuel pump can keep up ( which can depend on wiring / power supply ) ...

Other topic on fueling .. your running 91 octane... that will only support so much power before it knocks .. hence the ALKY .. what kit is it ? are you sure that it is adding enough alky at higher boost levels... .. what nozzle is in it ?

Just how much knock are you seeing ? where in the run is the knock ? Have you looked at your dataloggs ? are you datalogging your passes ?
what rpm drop are you seeing between gears ? When you raised the boost from 21 to 24 psi .. what did the MPH do ? What was the AFR .. did it knock ?

Have you tuned and run the car on pure Race fuel ? what did it run ?

You mentioned you don't have a lot of time testing it .. but above you mention its not humanily possible to get the car faster than it is .. Do you follow what im getting at ?
Regardless what the guys are saying above .. the first step to getting your car faster is to face the facts head on .. something is holding it back.. Tuner
I am sure with a bit more seat time and tuning .. YOU WILL FIND WHERE THAT POWER IS GOING ! Sorry I don't believe you are maxed out yet with the setup and sorry I don't subscribe into the philosophy of just ignoring an issue.

Im trying to give you ideas ... that power is going somewhere .. you just need to find it. A good running TTA with just bolt ons and NO internal work done will go easy lower 120's
Adding E85 in by itself isn't going to magically solve the issues.. it may mask them to a degree but not solve them
 
turbo89 said:
Convertor .. what type is it multidisc clutch ?

my TTA race weight is no where near 3800 pounds im about 200 .. car must have some subs in it ??

Your fueling ... it depends ... you may or may not have to touch the chip .. just raising boost does NOT mean you will have to add fuel in the chip.. the FPR should provide the added fuel... that is taking into account your fuel pump can keep up ( which can depend on wiring / power supply ) ...

Other topic on fueling .. your running 91 octane... that will only support so much power before it knocks .. hence the ALKY .. what kit is it ? are you sure that it is adding enough alky at higher boost levels... .. what nozzle is in it ?

Just how much knock are you seeing ? where in the run is the knock ? Have you looked at your dataloggs ? are you datalogging your passes ?
what rpm drop are you seeing between gears ? When you raised the boost from 21 to 24 psi .. what did the MPH do ? What was the AFR .. did it knock ?

Have you tuned and run the car on pure Race fuel ? what did it run ?

You mentioned you don't have a lot of time testing it .. but above you mention its not humanily possible to get the car faster than it is .. Do you follow what im getting at ?
Regardless what the guys are saying above .. the first step to getting your car faster is to face the facts head on .. something is holding it back.. Tuner
I am sure with a bit more seat time and tuning .. YOU WILL FIND WHERE THAT POWER IS GOING ! Sorry I don't believe you are maxed out yet with the setup and sorry I don't subscribe into the philosophy of just ignoring an issue.

Im trying to give you ideas ... that power is going somewhere .. you just need to find it. A good running TTA with just bolt ons and NO internal work done will go easy lower 120's
Adding E85 in by itself isn't going to magically solve the issues.. it may mask them to a degree but not solve them
Click to expand...
See now responses like this will get people to listen. I do know of a TTa with a 6152 running 125+ with pretty much your same mods. Keeping track of the MPH is how you can tell if the car is making more power, but can also help you figure converter slip. Also like he said seeing how much the rpm's drop on each shift is valuable info also. I do also agree that just changing to e85 won't make it faster, but right now of you're limited by octane, and not spraying enough alky to overcome the low octane e85 will definitely be a huge improvement. You can make a lot more power than 91, and might never need to spray alky again.
 
dvernst said:
See now responses like this will get people to listen. I do know of a TTa with a 6152 running 125+ with pretty much your same mods. Keeping track of the MPH is how you can tell if the car is making more power, but can also help you figure converter slip. Also like he said seeing how much the rpm's drop on each shift is valuable info also. I do also agree that just changing to e85 won't make it faster, but right now of you're limited by octane, and not spraying enough alky to overcome the low octane e85 will definitely be a huge improvement. You can make a lot more power than 91, and might never need to spray alky again.
Click to expand...

No .... typically you can tell people up front what they need to do and look out for ... they put it on the pay no mind list
THEN they don't run the times and just accept it as "ITS MAXED OUT .. TIME TO ADD MORE PARTS" without really taking into account whats happening.

Its when they are told .. HEY YOU HAVE AN ISSUE and it STARTS with the TUNER ! ... that usually gets the gears turning and we find out REALLY whats holding things back. Then they start learning more and then the performance follows
I have said it long before 2002 .. ITs not the parts that makes these cars go fast :)
 
89mulletbird said:
I have a Walbro 340 now but want to upgrade to 120lb injectors for E85, I know this pump and lines won't support it. What's the next step to take?
Click to expand...
Flow bench data posted on the racetronix website suggests twin walbro 340 pumps will flow ~128GPH @ 75psi with 16V. I would knock about 5% off that number when going from a flow bench into a car. Or about 121GPH. That's enough to keep the fuel pressure strong @ 75psi even if you ever ran those injectors wide open. (very well into the 9's on E85) Stock lines could support but they would have to be in tip top shape and even then if you watch the fuel pressure closely you might see some instability if both pumps are running and the injectors aren't consuming enough of it.

Another option is the 430lph walbro. I haven't yet seen any 16V data posted anywhere for that pump, but I estimate it can support about 105-110 GPH @ 75PSI with 16V (in a car). It's pretty close to fully supporting the 120's but it might not quite make it, especially if you run high boost and high fuel pressure. It would be interesting to see what it could do with 120's....
I spec'd this pump in a buddy's car with 95's (no volt booster) and it's been strong (and quiet too). Stock return line would be too small to handle the return flow at idle.
 
BEATAV8 said:
Flow bench data posted on the racetronix website suggests twin walbro 340 pumps will flow ~128GPH @ 75psi with 16V. I would knock about 5% off that number when going from a flow bench into a car. Or about 121GPH. That's enough to keep the fuel pressure strong @ 75psi even if you ever ran those injectors wide open. (very well into the 9's on E85) Stock lines could support but they would have to be in tip top shape and even then if you watch the fuel pressure closely you might see some instability if both pumps are running and the injectors aren't consuming enough of it.

Another option is the 430lph walbro. I haven't yet seen any 16V data posted anywhere for that pump, but I estimate it can support about 105-110 GPH @ 75PSI with 16V (in a car). It's pretty close to fully supporting the 120's but it might not quite make it, especially if you run high boost and high fuel pressure. It would be interesting to see what it could do with 120's....
I spec'd this pump in a buddy's car with 95's (no volt booster) and it's been strong (and quiet too). Stock return line would be too small to handle the return flow at idle.
Click to expand...
This spring I should find out for sure if stock lines are adequate.
 
dvernst said:
This spring I should find out for sure if stock lines are adequate.
Click to expand...
Yes sir, and that 5858 turbo will be well into the tens. Then nobody can tell you that your a sucky tuner and that your car is messed up!
 
Chuck Leeper said:
Suggest you stick to helping the OP....Otherwise there could be a "poof"....;)
Click to expand...


Chuck I was helping the OP ... for what he has that car should be a lot faster than it is ... and if he switches over to E85 just because he thinks that is the solution to find that performance .. he will be again disappointed and looking for more parts to add on...
Can you really tell me his car is trapping what it should be for what is done to it ?

and the guys adding fuel to the fire here aren't helping him ... saying everything is perfectly fine and add more variables isn't gonna help this guy get his car where it should be.
The simple information he posted up after the intial posts just reconfirms exactly what I suggested.. with that I posted up more suggestions .. not sure how much more help one can provide.
 
turbo89, thanks for all the suggestions, you asked many questions I can't answer now but will keep track of next time at the track.. I will be adding a fuel pressure sensor and wiring it into my Powerlogger to make sure my single 340 isn't dropping pressure also. I also want to upgrade to Erics closed loop chip to make tuning easier.

I have an Art Carr 9" lockup converter, I don't know much more about it than that. I do know when I lock it up I drop over 500RPM.

I'm going to a 1/3 mile roll on race day this month, that should give me plenty of tuning and logging time at higher speeds. Should be good enough to get some useful data to post.
 
dvernst said:
This spring I should find out for sure if stock lines are adequate.
Click to expand...
I went 10.7 @ 128 on 120's. 21lbs first gear, 20lbs 2nd and 22lbs 3rd. Duty cycle was 52% in 3rd with stock lines. Timing 22 *
Base fuel pressure is 58 with 2 Walbro 340,s on all the time. Voltage 15.2
A/F between 7.60-7.75
45A
 
turbo89 said:
Chuck I was helping the OP ... for what he has that car should be a lot faster than it is ... and if he switches over to E85 just because he thinks that is the solution to find that performance .. he will be again disappointed and looking for more parts to add on...
Can you really tell me his car is trapping what it should be for what is done to it ?

and the guys adding fuel to the fire here aren't helping him ... saying everything is perfectly fine and add more variables isn't gonna help this guy get his car where it should be.
The simple information he posted up after the intial posts just reconfirms exactly what I suggested.. with that I posted up more suggestions .. not sure how much more help one can provide.
Click to expand...

I understand the help part. I put myself in the OP's place, and didn't like the way you responded.
 
krom said:
I went 10.7 @ 128 on 120's. 21lbs first gear, 20lbs 2nd and 22lbs 3rd. Duty cycle was 52% in 3rd with stock lines. Timing 22 *
Base fuel pressure is 58 with 2 Walbro 340,s on all the time. Voltage 15.2
A/F between 7.60-7.75
45A
Click to expand...
I haven't had enough seat time to lean mine out. I was at 60% d.c., but af was 10.0, and maybe even a little richer. Logging my fuel pressure I was seeing some turbulence, and that's the main reason I was questioning my lines. I suspect it's my regulator though, cuz I've had it stick wide open a couple times, and the fuel pressure dropped way down.
 
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krom said:
I went 10.7 @ 128 on 120's. 21lbs first gear, 20lbs 2nd and 22lbs 3rd. Duty cycle was 52% in 3rd with stock lines. Timing 22 *
Base fuel pressure is 58 with 2 Walbro 340,s on all the time. Voltage 15.2
A/F between 7.60-7.75
45A
Click to expand...
How come you run your base FP so high?
 
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