800hp twin setup 12v

Diesel92 said:
Ok I miss read that comment as in rate your referring to the cam rate of the pump??
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cam duration. You just want it completely, or almost completely done throwing in fuel by the time you reach TDC.

Also,
Smokem, send me a PM back plz
 
I understand where the fuel needs to be and finding any info on that pump is not so easy. so I have no idea what cam it would be comparable to maybe a 215. I do no when it's pin timed it's at 15° so I added 7° of advancement or 3.5 mm so without knowing what the cam is its pretty much hit or miss till i get the timing right?
 
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Diesel92 said:
I understand where the fuel needs to be and finding any info on that pump is not so easy. so I have no idea what cam it would be comparable to maybe a 215. I do no when it's pin timed it's at 15° so I added 7° of advancement or 3.5 mm so without knowing what the cam is its pretty much hit or miss till i get the timing right?
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I bet whoever benched your pump can give you more insight as to duration, and you should find your old fuel card to find out where it is pinned to.
 
I didn't own the pump when it was benched. And I never thought to ask but I doubt he has it. Could I just spill port time it with a degree wheel and that would get me the closest?
 
I've have a 210hp pump that I bought to tinker with. Can't say exactly what the duration is, but I do know it's a "D" type cam like the 160/175hp pump. They like more timing than the 180/215s, due to a less aggressive injection rate (that's what I've been told). Mine also has 11mm P&B, so you might want to check that too.

Spill port is the best way to time it. I use compressed air. It's easier for me to hear air hissing, than watch the fuel drip.
 
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PES6P120A120RS7265 is the part number so according to that its a 12mm. I'm gonna run it and see what happens and probably going to go with and s480 to throw under the 351 then eventually get a s362 for the top. Any one know the best place for borg chargers?
 
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Injection rate can be effected by several things; delivery valve, plunger diameter, helix design, and camshaft profile. Understand that to get more fuel from the injection pump you must increase rack travel, the drawback being that increased rack travel also increases the amount of time fuel is injected, therefore requiring more timing advance.

12mm P7100 - 550cc's = 30° crank rotation injection window
13mm P7100 - 550cc's = 20° crank rotation injection window

Based on the above information used solely for comparison sake, you can see a larger plunger moves the same quantity of fuel in less time, therefore requiring less timing advance. Even though a 12mm pump will make enough fuel to meet your goals, you are backed into a corner where you will be forced to run a high value of injection timing to get the fuel in before TDC, and why I say spending money on a better injection pump will pay the largest dividends.
 
Ok that makes it much clearer now I understand what you're saying the more fuel you can push in before tdc with bigger plungers and a quick rate cam for ex. the less time you will need to put the same amount of fuel therefor less timing is needed. Thanks for the help. I'm gonna see what that pump can do being it only has 60000 miles on at and i can't see not using it for a little.
 
Knowing what I know now I would've probably considered keeping the spool flange, keeping a single s400, and invested in 13mm plungers. I'm at 32* right now with my 12mm 180 and it definitely does not run as good at part throttle as it did when at 26. Part throttle egt's are up about 100-150 and it is rowdy to say the least during the first cold start of the day! You could always add an adjustable timing gear but it would take one time for me to lose out on a spirited wot competition at low timing for me to get annoyed with that. Good luck.
 
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