Ateco 500efi upgrade
 

Has anyone tried this 600hp upgrade kit that I've seen in classifieds?

http://www.offshoreonly.com/classifi...o38686-en.html

Seems like a lot of stuff for the price if it works to bring a true 100hp.

That's a very nice price for all that is included. I have not heard of anyone using the setup, but that would really wake up a 500. Wish they had that posting last year when I rebuilt mine.

Without intake work and throttle body replacement, I seriously doubt you are going to see 600 hp. The intake is the limiting factor. The throttle body is not far behind.
Also, certainly not a knock against Ateco, but you can't really succesfully do a cal. for an engine with that many mods and get it 100% without tuning it. You can get it close, but every engine is different, therefore requiring a slightly different tune. It may run fine, but it will not be the best it can be. For this reason, I don't offer any "packages" or do I do any tuning through the mail.
Again, not a knock against Ateco. It's just something that I won't do. I have rarely seen it work out that good. However, it is a pretty good price on the parts.
Eddie

I was thinking the same.

Info
 

Irishtornado,

The 600 kit in classifieds is for a carb engine. The jetting of the carb will need to be motified, but we can help you with this. We have dyno sheets to substantiate.

Matt

Irish has 500EFI's.

Up to 125HP increase for your Merc 500EFI
 

We also offer a 500EFI kit. Its in the classifieds, "Up to 125HP for your Merc 500EFI"

Guarantee'd 125HP? I've seen both kit's and done lots of research. You have my attention.

We're doing something similar ( pro 1 heads, bigger cam,
asm throttle body, ecm mods)

Just got the ecm's back from getting re-tweaked, we try
them on the dyno again tomorrow...we'll see what happens.

Judging by what the air quality is suppose to be like tomorrow,
if we get 575 out of them, we'll probably do cart wheels:drink: