Questions on 525EFI setup
03-30-2012, 12:09 PM
#1
Questions on 525EFI setup
I have found a 525EFI intake and fuel system that I am going to purchase. I have never studied one up close, so I have a few questions.
Questions;
How much hp will it support without modification?
Do I need to find a wiring harness, or will my 454Mag harness be close enough with some minor modifications?
What size are the stock injectors?
Is my current MEFI 3 ECU compatible with the 525 sensors and injectors, or will they need to be changed?
Does the cool fuel mount in the same location as the 454/502 mags?
Thanks, Joe
Questions;
How much hp will it support without modification?
Do I need to find a wiring harness, or will my 454Mag harness be close enough with some minor modifications?
What size are the stock injectors?
Is my current MEFI 3 ECU compatible with the 525 sensors and injectors, or will they need to be changed?
Does the cool fuel mount in the same location as the 454/502 mags?
Thanks, Joe
03-30-2012, 11:53 PM
#2
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Joe:
The HP525efi manifold with no modifications will support about 600-610HP on a 540 cube engine before it runs out of air but this is based on cylinder head efficiency also.
The 454 mag harness should be modifiable to fit the intake. You need to have the plugs that reach the injectors under the plenum which is almost identical to the HP525 wiring under the plenum. You will also have to probably lengthen the plugs for the throttle position sensor, the map sensor, and the IAT sensor. You might have to also modify the length of any water temp sensors that run to the front of the block if they route that way on the 454mag. That should take care of the intake manifold area.
As for injectors, they are approximatly 42lb/HR injectors and we have gotten them to support about 625HP by raising the pulse times to reasonable levels and it sounds like you have reprogrammed your ecm already for your previous mods. You can also by-pass the stock cool fuel fixed pressure regulator and up the fuel pressure to 50 psi from the stock 43-45psi of the fixed regulator on the cool-fuel.
Your Mefi 3 ECM will run your injectors just fine but you will most likely need to reprogram injector fuel mapping in the ECM.
The HP525efi cool fuel is under the front recess behind the balancer on a stock HP525efi but the fuel water seperator and delivery lines are 3/8" fittings and line size and I think your 454mag has 1/4" sperator fittings and line sizes. Pretty easy to upgrade these as needed. We have some HP525efi cool fuels and brackets as well as some lines and seperators if you find you need them.
We did so much testing and mods and rework when we developed our Raylar HP675efi upgrade for the HP525efi engine. I hope this info helps.
Best Regards,
Ray @ Raylar
The HP525efi manifold with no modifications will support about 600-610HP on a 540 cube engine before it runs out of air but this is based on cylinder head efficiency also.
The 454 mag harness should be modifiable to fit the intake. You need to have the plugs that reach the injectors under the plenum which is almost identical to the HP525 wiring under the plenum. You will also have to probably lengthen the plugs for the throttle position sensor, the map sensor, and the IAT sensor. You might have to also modify the length of any water temp sensors that run to the front of the block if they route that way on the 454mag. That should take care of the intake manifold area.
As for injectors, they are approximatly 42lb/HR injectors and we have gotten them to support about 625HP by raising the pulse times to reasonable levels and it sounds like you have reprogrammed your ecm already for your previous mods. You can also by-pass the stock cool fuel fixed pressure regulator and up the fuel pressure to 50 psi from the stock 43-45psi of the fixed regulator on the cool-fuel.
Your Mefi 3 ECM will run your injectors just fine but you will most likely need to reprogram injector fuel mapping in the ECM.
The HP525efi cool fuel is under the front recess behind the balancer on a stock HP525efi but the fuel water seperator and delivery lines are 3/8" fittings and line size and I think your 454mag has 1/4" sperator fittings and line sizes. Pretty easy to upgrade these as needed. We have some HP525efi cool fuels and brackets as well as some lines and seperators if you find you need them.
We did so much testing and mods and rework when we developed our Raylar HP675efi upgrade for the HP525efi engine. I hope this info helps.
Best Regards,
Ray @ Raylar
Last edited by Raylar; 03-30-2012 at 11:59 PM.
03-31-2012, 08:07 AM
#3
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I did almost the same swap. I put a 500EFI intake on a 502 mag engine. Had to lengthen only a couple wires on the 502 mag harness. I reused most of my original 502 mag. sensors. I installed a Tyler Crockett top mount throttle body kit. This 540 engine made 693hp on the dyno. Jeff Wurl
Last edited by jwurl; 03-31-2012 at 08:11 AM.
03-31-2012, 11:01 PM
#4
I did almost the same swap. I put a 500EFI intake on a 502 mag engine. Had to lengthen only a couple wires on the 502 mag harness. I reused most of my original 502 mag. sensors. I installed a Tyler Crockett top mount throttle body kit. This 540 engine made 693hp on the dyno. Jeff Wurl
