Offshoreonly.com - Dyno and pics of a SLIGHTLY modified 502 Mag MPI

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Eddie - is that the 950cfm throttle body?

No, that is the 2000 cfm throttle body. Holley also has a 1000 cfm that is on a 4150 flange. The 2000 is a 4500(dominator) flange.
Eddie

Eddie, I have the Holly 1000 cfm system on a 502 but using the MEFI system. The injectors are marked with a H-36.

Any idea on my hp limitation with this set-up?

Quote:

Originally Posted by Young Performance (Post 3158252)

The Holley setup is not much taller than the stock 502 Mag intake. I will check on the exact height of it and get back to you.
Eddie

Thanks Eddie, that would be awesome. I'd know what I was dealing with ahead of time!

Quote:

Originally Posted by onesickpantera (Post 3158472)

Eddie, I have the Holly 1000 cfm system on a 502 but using the MEFI system. The injectors are marked with a H-36.

Any idea on my hp limitation with this set-up?

You will be limited by the injector size, not the throttle body. The formula is as follows:

Injector rating x # of injectors x injector duty cycle% / Brake Specifc Fuel Comsumption

In your case of the 36# injectors:

36 x 8 x .85 (85% is the average max.) / .5 (average NA BSFC) = 489.6 hp

You can certainly run a little more than 85% duty cycle. These figures are also at 3 Bar fuel pressure. You can run a higher fuel pressure to support more power as well. Your particular engine may also have a lower BSFC that will help. Bottom line, you have enough injector for about 550 hp. Any more than that will take larger injectors. However, the throttle body is large enough to support as much as you can make NA. Hope this helps.
Eddie