lots of fuel, no control

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fastbarry

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Apr 10, 2011
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i had my pump benched and the shop was able to get 335 cc of fuel at 17 mm of rack. any further rack travel put the spill port on the back side of the helix and fuel out put jumped to 650cc's but with out any throttle control past 335 cc. i have the pump plated ant 17mm right now.

backstory:

the truck is a 97 f350 that i am in the middle of doing a cummins conversion. for turbos i will have a s363 ish size turbo (dont have yet) hangin on a header over an s480 (that i allready have). injectors will be 5x.016. the cyl. head will be mildly ported and have a 3 angle valve job. i will run the stock cam for now. it has head studs and the head is o-ringed.

i am wondering what to expect if i do pull the plate out. fuel will instantly jump from 335 to 650cc of flow. will i put the fire out with to much fuel or will it come unhinged like i hit a nitrous switch?



i am curious what input or experience any one may have.


thanks
barry
 
fastbarry said:
i had my pump benched and the shop was able to get 335 cc of fuel at 17 mm of rack. any further rack travel put the spill port on the back side of the helix and fuel out put jumped to 650cc's but with out any throttle control past 335 cc. i have the pump plated ant 17mm right now.

backstory:

the truck is a 97 f350 that i am in the middle of doing a cummins conversion. for turbos i will have a s363 ish size turbo (dont have yet) hangin on a header over an s480 (that i allready have). injectors will be 5x.016. the cyl. head will be mildly ported and have a 3 angle valve job. i will run the stock cam for now. it has head studs and the head is o-ringed.

i am wondering what to expect if i do pull the plate out. fuel will instantly jump from 335 to 650cc of flow. will i put the fire out with to much fuel or will it come unhinged like i hit a nitrous switch?



i am curious what input or experience any one may have.


thanks
barry
Click to expand...
You use the AFC to control the fuel. Id run without a plate but that's just me.
 
Get a different pump, I'm assuming the plunger has an upper helix?
 
i know you control things with the afc and i will be spending time tuning mine. what i am saying though, is at 17mm of rack travel it make 335cc and at 18 mm of travel it immediatly jumps to 650cc. there is no throttle control past 335. it will be like an on-off switch that doubles the fuel out put at that point.

the pump is a 190 hp pump out of a 95 ford school bus.
 
fastbarry said:
i know you control things with the afc and i will be spending time tuning mine. what i am saying though, is at 17mm of rack travel it make 335cc and at 18 mm of travel it immediatly jumps to 650cc. there is no throttle control past 335. it will be like an on-off switch that doubles the fuel out put at that point.

the pump is a 190 hp pump out of a 95 ford school bus.
Click to expand...

Find a pump;)

Chris
 
Smokem said:
Get a different pump, I'm assuming the plunger has an upper helix?
Click to expand...

i can not answer that. i am simply going off what the pump shop told me about the fuel curve.

i would prefer to get a different pump but this is what i have for now. if the right deal on a pump comes up i will definatly snatch it up though.
 
Not what you wanted to hear, but I wouldn't tell you to waste your time. Run it up to 17mm rack, but the cam is still reverse inhibiting with poor fill time.

From time to time you will see people brag about these big 12mm flow numbers, what they don't realize is that they shouldn't be bragging, the duration hangs out and there is no power with that much fuel vs time.
 
what pumps should i be looking for. i know i dont want a 215 because of the timing retard build into them. my goal is 700 hp on the street but room to grow is always nice.

i have heard 180's are the ticket. what numbers should i be looking for?
 
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