5.3/ Radix / 224/224 112 LSA meanwhile ???
#11
Were you able to get AFR or Fuel Pressure readings? If you are using the stock oxygen sensors then try to not be over 920 for a reading at the top of 2nd gear. It sounds like you may be in the high 900's right now.
#12
Hey guys, I recently decided to get BLOWN
and I have some questions as I am new to this.
I'm installing a Radix on my 5.3 with a 224/224 cam 112 LSA and planning on switching to a gt-2-3 in like a month.
Is there any problem running this cam for a while? I can feather foot for a while
Would the 42# injectors be enough for the gt-2-3?
If yes, Is there anyone running them and can you post the duty cycle?
Pease go easy on me and welcome me to the FI side, and sorry for all the
and I have some questions as I am new to this. I'm installing a Radix on my 5.3 with a 224/224 cam 112 LSA and planning on switching to a gt-2-3 in like a month.
Is there any problem running this cam for a while? I can feather foot for a while

Would the 42# injectors be enough for the gt-2-3?
If yes, Is there anyone running them and can you post the duty cycle?
Pease go easy on me and welcome me to the FI side, and sorry for all the
I was fine with the 42's but swapped to 60's. I see ~66% IDC with the 60's.
#14
Bottom line, don't trust nor use a stock O2 sensor for "tuning".
#15
Stock O2s are completely inaccurate at A/F readings richer than ~13.7:1. There are plenty of datalogs "out there" (and in my old databanks) that compare a wideband to a stock narrowband O2, and 900mv can just as easily be a true AF of 13.0:1 as it can be 11.0:1....
Bottom line, don't trust nor use a stock O2 sensor for "tuning".
Bottom line, don't trust nor use a stock O2 sensor for "tuning".

#16
You are probably running real rich or the fuel pressure is dropping off. It is likely that the Power Enrichment rate is real high due to fuel pressure falling off or it is just super rich under boost.
Were you able to get AFR or Fuel Pressure readings? If you are using the stock oxygen sensors then try to not be over 920 for a reading at the top of 2nd gear. It sounds like you may be in the high 900's right now.
Were you able to get AFR or Fuel Pressure readings? If you are using the stock oxygen sensors then try to not be over 920 for a reading at the top of 2nd gear. It sounds like you may be in the high 900's right now.

My Brother has gone through 2 pumps (walbro 255) as well as a friend. They are both running Pro Charger with 60# injectors.
My tuner is using a wideband as well.
Trever- I'm using the 8# pulley but getting only 4-5#/ no meth/ and plan to run it that way until I get a 6.0
Last edited by La Riddler; Dec 30, 2007 at 04:28 PM. Reason: addition
#17
9 Second Truck Club
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From: Colorado Springs, Co/ Central, Ca
Sorry, I failed to mention the problem I had with the walbro 255 in-line. It would drop pressure on wot, so I went with the in-tank model and worked fine that day. When we were about to log it today, I checked the fuel psi gauge and it was @ 40psi and raised to 50 on wot. We still tryed it and realized that the injectors were topping out which at first they were running @ 78% DC or so, with the in-line pump. These Walbro's are driving me nuts.
My Brother has gone through 2 pumps (walbro 255) as well as a friend. They are both running Pro Charger with 60# injectors.
My tuner is using a wideband as well.
Trever- I'm using the 8# pulley/ no meth/ and plan to run it that way until I get a 6.0

My Brother has gone through 2 pumps (walbro 255) as well as a friend. They are both running Pro Charger with 60# injectors.
My tuner is using a wideband as well.
Trever- I'm using the 8# pulley/ no meth/ and plan to run it that way until I get a 6.0

#18
Sorry, I failed to mention the problem I had with the walbro 255 in-line. It would drop pressure on wot, so I went with the in-tank model and worked fine that day. When we were about to log it today, I checked the fuel psi gauge and it was @ 40psi and raised to 50 on wot. We still tryed it and realized that the injectors were topping out which at first they were running @ 78% DC or so, with the in-line pump. These Walbro's are driving me nuts.
My Brother has gone through 2 pumps (walbro 255) as well as a friend. They are both running Pro Charger with 60# injectors.
My tuner is using a wideband as well.
Trever- I'm using the 8# pulley/ no meth/ and plan to run it that way until I get a 6.0

My Brother has gone through 2 pumps (walbro 255) as well as a friend. They are both running Pro Charger with 60# injectors.
My tuner is using a wideband as well.
Trever- I'm using the 8# pulley/ no meth/ and plan to run it that way until I get a 6.0

No matter what injector you use you need to make sure the pressure is always consistant. I am getting ready to upgrade my fuel system with a Custom Sump Tank and Aeromotive Fuel Pump. I am going to set mine up with a boost referenced Fuel Pressure Regulator that will increase fuel pressure under boost. I will run 60psi from idle to a certain boost level then increase it to compensate for the boost pressure against the injector.
#19
One side effect from putting on the radix with that cam is that it will magnify the lope and you'll get some strong "rotor knock" from it. You'll need to raise your idle rpms more than normal to correct the issue. I ran a 218/218 114 cam on my 6L. I had it tuned to purr like a kitten. I dropped the radix on it and it would lope and die until I raised the idle rpms up even more. When it lopes (misfires), you'll hear the rotors in the radix 'knock' from the sudden decrease in rpm. I'm not sure if the knocking does any damage, but its loud and doesn't sound good.
#20
No. I didnt cut the bottom and used the stock type strainer. I was told the same as for the regulator that reads boost, I will look into that. And we got rid of the low rpm knocking. It does sound bad like something is banging dry and hard....not good.
Hope that I can still use the 42# injectors after I fix this fuel pressure issue. I'm still going with the Gt2-3 so whatever it takes, Go Big Or Go Home!!!!!!
Hope that I can still use the 42# injectors after I fix this fuel pressure issue. I'm still going with the Gt2-3 so whatever it takes, Go Big Or Go Home!!!!!!


