regalman4925

working on a stock 502 mag, adding gils to it and wanna start working on building some power. it is efi, are we better off going to a carb setup? we have a 731 cam, a hp500 cam and a vortec super charger in the shop. do we need to get the seals swaped on the heads to clear a higher lift cam or will we be ok? also the springs? we have isky 8205 springs to go with the 731 but i have heard that the 731 swap rigt into the 502 mag, not sure if that is true or not? next question, if we keep the efi do we need to flash the computer for the cam? another option is to clone a hp500, is there any difference on the lower end of a hp500 verses the 502 mag? also if we wated to go to a 525 efi setup? we know of a complete 525 efi setup and a cam. we also have the vortec sitting here, is it worth playing with that and the efi or is it gonna not gonna be the rigth direction for this? we more or less want to figure out what the right direction to go right now, kinda want to start with the gils, a cam, msd box and roller rockers and then move on to the next step next winter.

baja_brian

Wow, this is making my head hurt.

I am interested to see what combinations are out there for this. I think some head work will be a big start but not sure on valve size and springs.

Young Performance

Let's start with hp. Your options are all over the place and differ quite a bit from one to the other. Which is the correct route depends on how much power you want and your budget. That will determine the best route to go. Do you have a hp amount you want or a particular speed increase or top speed in a particular boat?
Eddie

regalman4925

baja brian and i called rmbuilder and talked to him about brians 502. from what we got from him the best option to go on this motor is carbed using a victor jr intake, some air flow research heads, one of his cams and all of the matching components to make it all work. says we will hit a honest 600 hp with this setup and be sitting under 5k total invested. i think brian is still a little hesitant on giving up the efi but like bob said, it is a great stock setup and it works well but efi is allot tougher to build power with and the manifold is gonna top out around 500 or so hp. so it sounds like we are going in a good direction, we have a plan!

Young Performance

That 502 MPI intake is a huge limiting factor. With some work, it will make about 550 hp. A better bet would be to use an efi setup like Holley has, if you want to keep EFI. They have a single plane setup that is very similar to a single plane Dart intake(but with injector bungs casted in), fuel rails, injectors, 2000 cfm throttle body, crossover tubes, regulator, etc for about $2500. This will allow you to make whatever you want for power and keep EFI. Edelbrock also makes a similar setup. One of those EFI setups, bump the compression, and a set of good aluminum heads, and you will make 600 hp without even trying. You will also have the cold start, driveability and protection that EFI has to offer. Good luck.
Eddie

Here is the Holley setup.

ZXXX Donzi

Young Performance here worked over my 502 Mag. I still have the EFI. It starts and runs better than before. The only difference is that it sounds meaner and makes 942hp! He was able to use that 502 Mag manifold too. Oh yeah, a little forced induction also helps.

I would let Eddie do one of his EFI setups for you and you won't have to touch a thing when it is all over. Just put gas in, change the oil and drive it. You can take advantage of the technology available in the new century. It does not cost much more.