Dyno and pics of a SLIGHTLY modified 502 Mag MPI
 

Here are some pics of a slightly modified:drink: 502 Mag MPI that we just finished. It is now 547 ci with Dart Pro 1 heads, Holley EFI intake, 2000 cfm throttle body, MEFI 4 ecm, etc, etc, etc.
I have received a ton of calls lately asking what can be done with a 502 Mag MPI to make more power. I thought those guys would like to see this. This may give you an idea of what that engine can look like and what kind of power it is capable of making. It ended up making 688 hp and 665 ft lbs of torque. It is going in a 28 Advantage of a fellow OSO member.
I received it as a stock 502 Mag with damaged Pro1 heads and a burned piston. Here is what it looks like now. Enjoy, and thanks for looking.
Eddie

A few more.

Here is a link to one of the dyno pulls. Enjoy.
http://www.youtube.com/watch?v=tlly31htQH8

Nice job Eddie!

blue !!!!!!!

Looks nice Eddie. I really like the serpentine belt system you use for the accessories.

Nice work Eddie and some good numbers.

Sounds like something I'd like to do. How about reliability and hours before refresh is needed?

Drum roll please, How much $?

In the video the accessories were not turning. That tells me the horsepower number is not real world. Just curious why you dyno with the belt off ???

No, the numbers are still real. I am not set up to run the sea water pump. Since it is a serpentine system, I have to remove the belt for everything. On the v-belt setups, I run everything but the pump. I am using city water to cool the engine, so the pump will suck more than the city water lines can supply and end up collapsing the hose. Ask me how I know!!
The engine was making 415 hp before I got my hands on it. It now makes almost 700 hp. Regardless of whether the accessories are turning or not, I think it is a pretty good jump in power. The customer seems to be pleased with it and that's what matters to me. I really wish I could run the accessories, but I can't at the moment. I will get it set up at some point.
Eddie

I will send you a pm. I don't like to advertise what my customers spend. If they want to post it then I am OK with it. It's just not my call. Their wives might be reading:lolhit:

It is a good jump in power regardless of whats being driven.

Tidy packaging and clean presentation Eddy.

Clean and reliable no air pushing BS to deal with probably gets super mileage as well.

Question though, Im rebuilding my 406 and decided to stay demon carb vs pay for injection -with a wet exhaust where do you put the o2 sensor so the injection can compensate for altitude?

Nice thanks for sharing.

Uncle Dave

Thanks Uncle D.
I install the O2 sensor in the collector or riser just after the 4 pipes come together. The Mefi does not run in closed loop, so the O2 is just for my personal use in tuning. It does have an altitude compensation but must be manually completed. I have it good up to about 5000 ft. Any more and I would have to go there and do the tuning personally.

Thanks everyone else for the kind words.
Eddie

It is no less reliable than the 502 Mag. However, it won't have the longevity that the 502 has. I recommend a rebuild at 400 hours. You could go longer, but the odds of having to bore it bigger are pretty good. Most of the time if they are done at 350-400, then they will go back at the same bore. Like I said, if you wait longer, the rebuild will cost a little more.
I do a VERY thorough rebuild, so you end up with essentially a new engine when it's done. Thanks
Eddie

Ok How do you know?:evilb:

Well, just like most things I had to learn the hard way. It's either the hard way or no way.:grinser010:
Tried to do it and sucked the hose closed, burned up the impeller, overheated the engine, had to clean out all the pieces of burned rubber, etc., etc., etc.
You had to ask huh Mike??? Don't you have something to plant, or pick, or milk???:evilb:
Eddie

Very nice results and excellent rigging. What type and brand lifters did you use?

Thanks Ben. I use Morels, Morels, or Morels. If I can't find them then I use Morels.:lolhit:
I have used others with success but I really like the Morels on the bigger hp engines. I haven't had any problems with them so I am going to stick with them.
Eddie

Solids or hydraulic?

I'm sure it is a hydraulic roller.

That is correct. It is a hydraulic roller. Pretty mild one at that.
Eddie

Very Cool!!! I just turned 400hrs on my stock 502's. I'm thinking when re-build time comes a knocking this is the way to go. Thanks for sharing eddie

Thanks Baywatch. When they are ready for a rebuild, give us a call if we can help.
Eddie

You ever do any of these with a FAST XFI setup or something similar? It seems like that would be nice for in boat tuning. I don't know how well that stuff will hold up to a marine environment though.

How much does something like that cost?

No, I don't for a few reasons. First, the Mefi has knock protection and the FAST, as well as most all aftermarket ecms, do not. Next, the Mefi can be serviced by any Merc. technician with a Merc scan tool. They do not have to bring it back to me if some problem arises with the ecm or a sensor. That pretty much never happens, but if it did, it wouldn't have to come all the way back to me. Their is a Merc. tech with a scan tool where ever there is water. They can treat it as if it were a 500 efi, 502 Mag, etc.
Eddie

I sent you a pm. I don't like to advertise what my customers spend on an open forum. Their wives might be reading.:lolhit:
Thanks, Eddie.

That Apache would rock-n-roll with that power! :coolcowboy:

So would your Checkmate:drink:

Boy, am I late to this party. May was a screwy month. I am extremely pleased with the results especially with the pos I shipped to him. Here are a couple of shots of the damage (thanks AZSM!!) that he was able to correct. Also the heads are only 310s and Eddie did a really good job on the port work.

Yup. I wanna know too :party-smiley-004:

We all do! Maybe the customer could put up a ballpark number (or a fake low one for the wife to read, and PM the real one haha).:drink:

Thank You Eddie
 

After Eddie put the engine in, finishing up the rigging, and did some test running I picked up the boat and my first use was a 300+ mile round trip and had no issues with the engine.

Started out at Kuttawa, KY (Lake Barkley) and ran up the Cumberland River to the Nashville riverfront docks. Stayed a few nights along with a run to Old Hickory Lake then made the trip back to Kuttawa.
I had 6 people, luggage, two coolers, and many cases of beer. :drink:

I made this same trip 4 years ago and this time I was able to run at a higher RPM which allowed for a faster run and used about the same amount of fuel as the old 509 motor.

Extremely happy with Eddie's service.

Eddie can you put together a kit w everything but the shortblock? Heads, cam, intake, TB, ecm tune, and ecm bracket? It can be the YP680 :evilb::evilb:

Eddie,

What would you recommend if I wanted to get another 125hp or so out of a stock 502mpi? The motor shouldn't be having a rebuild for quite some time yet so I don't want to tear into the bottom end.

Just trying to get an idea of what's involved to get to the 540-560hp level without affecting longevity drastically?

Sure, but it will be a ballpark tune. They all differ a little bit and the best way to do it is to put it on the dyno. Give me a call when you get a chance and we can discuss it further.

Shane, glad you guys had fun. The pics were great. I would love to make that run one day. Glad the boat ran great for you. Thank you again for your business. Talk to you soon.
Eddie

This one got a ton of extras that, while they look awesome, are not required and don't make any additional hp. For example, the serpentine accessories, 2 piece valve covers, electronics bracket, etc. To duplicate this engine; 547 ci, Holley injection, Mefi 4 ecm and harness, aluminum heads, entire valvetrain, custom oil pan, custom paint, oil, water, and fuel plumbing, etc, without the bling can be done for around 15K. However, you can easily hit over 20K with extras. The only items that we reused from the original 502 were the block, bell housing, coupler, and motor mounts. Every other part was replaced. If anyone has any questions, please do not hesitate to contact me. Thanks
Eddie

In order to get to the 550 hp area, you will need several things. First, the best thing to do is to get rid of the stock intake. I don't normally recommend having it modified (extrude honed, runners shortened,etc) unless you are supercharging it. If you want to keep it NA, then the Holley intake setup is a MUCH better choice. You will also need a cam change. Lastly, a bump in compression will be required.
If you chose to change the stock cast iron heads to aluminum (plus the above items), then 600+ hp would be possible from your 502ci.
Eddie

Hi Eddie,

That all sounds terrific. Height under the hatch is at a premium (I think there might be 3"-4" of clearance with the stock 502 manifold so while I'd love to change it out, we may need to go with a front feeding version.

Just starting to think about the project now - no definitive timeline.

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