Carpe Diem take 2
 

First winter I had the boat I put on 2" spacers in hopes of avoiding the 5000rpm burnout to get on plane .. long story short , spacers never really helped, planing is ALL in the cupping of the props and prop rotation.
This weekend I finally got rid of the spacers in hopes of more speed and rpm (could only turn 5300rpm) I also wanted to make sure AFRs were good to go.
At the same time swapped lowers to turn the props IN.

So left the family at home and with 2 new 02`s , the Mild Thunder man and his notebook , a box of jets, and the Go Pro we headed to the river.

Results were good,
Very Humid air and 80*
AFRs low 11`s to high 10`s
Gets up on plane at 3200 no problem
Acceleration even at 5000rpm is pretty sweet! No more enemic turd

Intake temps under the blower 140-150* (no intercooler )
6psi @ WOT
4% underdriven
100 gallons of fuel
Speed improved by 4-5 mph (84ish) on dead flat water.
Almost 6000rpm on port 5800ish starboard.
Second year with boat I`m pretty happy with that , on the lake with some chop she should scoot pretty good.:daz:


https://www.youtube.com/watch?v=U3zQvghTrf0&feature=youtu.be

very cool . what drives are you running on that boat ?

Heres my novice question.... Whats the smoke coming off the port engine? Just a breather on the valve cover?

Yeah....what does a guy do for a living to drive a boat like that. Lol sounds bad ass man!

Nice Job!! Glad to see that hard work paying off for you.

A little data

3000RPM = 12.0 AFR. 1" vacuum. 48mph Intake air temp 140*

3500RPM= 12.0 AFR 1psi boost. 52mph 130* intake air temp

4000RPM= 11.8 AFR 2psi boost. 62MPH 130* intake air temp

4500RPM = 11.5 AFR 4psi boost 69mph 135* intake air temp

5000RPM = 10.9 AFR 6psi boost 76mph 135* intake air temp.

WOT = blew pen out of my hand.


I dont have to tell you cig guys, this boat needs chop. Temp today was about 83*, but humidity was around 80% on down along that river corridor. Should wake up a bit on the big lake with better air and some chop to get that old hull loose.

IMO, with air intake temps about 50* hotter than ambient at full tilt, I question the gains an intercooler would offer on this low boost setup.

They are speedmaster 4 drives on boxes.

looking good

Very nice!

Yeah that engine pukes a bit of oil out that breather as you can see.. I have a high tech sock over the breather.
:bunnydance: