docmanrich37

Has anyone converted from the hp500 to 525efi by installing the efi system on the engine.What did you have to change internally if any.Was told just heads and cam.Where can i find the specs on what the 500 and 525 has internally like heads and cam.went to the merc site and it only tells you what the bore and stuff is.

Mikey Likes It

Good question I would like to know as well.

GETTINBYE

Yes the cam is different and the 525 EFI uses aluminum cylinder heads made by Edelbrock specifically for Mercrusier. Cam for the HP 500, if carbed, is a Crane 169611. If a HP 500 EFI model then the cam is a Crane 169621. The cam used in the 525 EFI is also a Crane which is, for the most part, a 168741 with 114* centerline instead of the 168741's 112*.

Hope this helps. Go the Cranes website using these grind numbers and get the cam card for each.

Mark

docmanrich37

Thanks these will help alot.

stevesxm

are you saying that heads, cam and efi only buy you 25 hp ? am i reading this right ? geeze sounds like the most expensive 25 hp in history.

docmanrich37

Actually 500 hp are only 470hp and 525efi are dynoed at 525-540hp.so if you had to rebuild them anyway and it would give you efi's too.$10,000 total for 100hp.i wi**** was that cheap a couple months ago.$30,000 tp get about 250hp per doggy and 20 mph so far.

lucky strike

iTrader: (1)

525 efi also has closed cooling
I've got two 525 efi short blocks with 200hrs for sale 1 has a broken valve.
They are 2003 engines

docmanrich37

The only problem is that he needs exhaust for the 525's and you can only get it from merc.Lowest price so far is $14,400 for 2 sets.Not worth doing it that way.The exhaust would be worth more than the motors.Merc is crazy.

lucky strike

iTrader: (1)

You can get the exhaust from Trick Marine, they are CMI Big tube.
My guess would $ 4,000 per engine, ck with Fred @ Trick

docmanrich37

Already went that route and Fred can't.Merc only the list for $10200 from merc price list.