500 efi with a 525 cam installed
 

Ok, I just recently had my 500 efi engines rebuilt. I had the engine builder install 525 cams. They dynoed out at 524 hp and 530 hp. Put them in boat, builder also checked tune while in boat, I also installed wide band air fuel guages for both motors and that was between 11.8 and 12.5. These engines are installed in a 36 foot baja. Last year the boat with 500 efi tired engines at 556 hrs went 71 mph at 5200 rpms. Now with the 500 efis with 525 cams runs 70 mph at 5000 rpm. I feel like I went backwards and the boat should run 73 to 74 mph at 5300 to 5400 rpm. Intakes and throttle bodies are stock. Just reaching out to see what the thought is on this. I'm thinking of buying bigger throttle bodies and tune it agian afterwards. What's your thoughts.

Yes, everything was on them. And we did six pulls on one and three on the other

even used my fuel pumps

5300 rpms 524.2 HP and 4,000 rpm 566.1 torque. Yes same pitch prop

I agree with you BAJA Rooster on the props I am only running a 26 pitch prop before and after engines were rebuilt. Also if I wasn't getting enough fuel wouldn't that show up in the wide ban. I have sensors in my tail pipes to make sure its not running lean or to rich.

Are e sure the tune is spot on ? Doesn't sound so with some AFR#s in the 11.5's.

ArcticFriends just got 40-50_hp on a customers set of engines doing more fine tuning. It happens ! Thread is a few away from this if you click on "New Posts"