113 injector size

[475wildey]

with 4.22 gm sec injectors well i be getting too far into the duty cycle time for a 113se cnc htcc heads 56mm hp inc t.b. tman 650 cams [.650 lift 258 in 260 ex duration 99 and 110 lobe centers] 10.6 to 1 fatcat ex...what injectors should i be using???

[Mike]

I would go witht the V-rod injectors p/n 27665-01 to be safe. We've ran these to 170hp on 120ci big twins without problems. This, of course, was using Race Tuner so that we could change injector sizing in tuning constants. These are small enough to give good drivability but still satisfy the hp.
Thanks, Mike

[475wildey]

Do you know what the rated flow of those would be?

[Mike]

Race Tuner uses a value of 4.81gm/sec, but this may be the not actual since they often change flow rate in tuning constants to allow VE values more latitude. We've threatened to have a bunch of injectors flowed but have yet to collect them all (we have a local guy who flows and calibrates injectors for race engines). The problem is that these things flow all over the place so you have to flow a batch of the same injectors to get an average. HD currently uses 7 different injectors depending on year and model, with more being introduced. We are simply selecting sizing based on HP numbers we've been able to achieve with specific injectors. The math on those we have tested does match the HP point where tuning problems start to set in.
Thanks, Mike